Wondering About The Past

Imagine yourself inside a completely empty void. When I say empty, not only do I mean that there are no objects, no mass or energy, but also that there is neither time nor space. There is only compete and utter nothingness, everywhere and everywhen. Bear with me, because I am really quite serious about this: close your eyes, screen out as much of the world around you as you can, and really try to place yourself in just this situation.

Difficult, isn’t it? In fact, I’ll bet that you find it utterly impossible. There is a good reason for this. It is impossible. It is impossible because the very act of imagining a void places you inside the void, whereupon it is a void no longer. The moment you are there you are mass / energy taking up volume, and so there are these phenomenom, and well as space. Events are happening (even if just the beating of your heart), so time exists as well. Mass, energy, space, and time are inexorably linked together. You cannot have one without the other three. As you are mass / energy, taking up space / time, the very act of trying to imagine an empty void ends its existence.

This is, admittedly, more of a philosophical argument than anything derived from physics, and I suspect that any physicists reading it are doing so with a jaundiced eye. It certainly isn’t a rigorous argument, but I think it is a good place to start wondering about the past because, if a lot of modern physics is correct (there are dissenting views), our entire universe has a beginning, before which there really was nothing, mass, energy, space, or time. Perhaps there were no physical laws either, as difficult as it is to see how the very concept can make any sense.

That beginning has a name, a name that ironically has found its way into common usage because its author, Fred Hoyle, intended it to be more of an insult to discredit it than anything else. It is, admittedly, a rather silly name for a scientific theory, compared to, say, General Relativity or Quantum Mechanics or Evolution by Natural Selection. It also has the flaw of not being a particularly accurate way of describing the beginning of the universe; the phrase “Big Bang” implies an explosion of matter and energy within a pre-existing space and time, rather than the initial expansion of space-time as well the matter and energy which occupies it.

In calling it “the initial expansion” I am not being much more accurate, however. There is no point in the evolution of the universe where can point to and say, “The Big Bang ends here; everything after this point is just ordinary expansion.” The truth is, the Big Bang is not a theory of how the universe got started; it is a theory of how it has evolved and still is evolving and will evolve that reaches right back to its very beginnings, back to time zero, assuming that there was a time zero and whether that term has any meaning. It is also not a theory of how or why that expansion began; there is a lot of scientific speculation about what might have been happening before time zero which lead to the Big Bang, but (almost) none of that speculation describes or modifies the Bang itself. Lastly, an important perspective to maintain is that we are not mere observers of but are living amidst the Big Bang, yes, right now even as we go about our busy little lives it is happening right here and everywhere else in the universe, an event which probably has many, many trillions of years to go or more, assuming that it will not continue forever, which at this point in our understanding of it is not at all clear.

And having said all that, I must now confess that I’m still not describing it with sufficient precision. I speak as though it is iron-clad scientific fact that the universe has a beginning. We do not understand the laws of physics well enough, however, to make so powerful a claim. All we can do is: ( a) observe now that the universe is expanding; (b) imagine reversing time so that the universe is contracting; and (c) extrapolate the time-reversed contraction until we inevitably encounter a situation in which all matter, energy, space, and time in the universe are compressed into a single point, a so-called “singularity”, at which moment our extrapolation comes to an end by logical necessity – by mathematical definition, nothing can by smaller than a single point. This is where we run into trouble, however. We cannot follow (c) to its logical conclusion with certainty because nobody knows what the laws of physics are beyond a certain degree of compression and temperature; as the universe gets smaller, hotter, and denser the set of rules of how matter-energy-space-time behave under such conditions are less and less well understood. When you get to the point where you don’t know what the rules are anymore, you simply can’t extrapolate any further. Thus, (c) is really just a conjecture; we cannot say whether there was a beginning or not. It is an important point to keep in mind because you will routinely encounter statements such as “the universe is 13.73 ± 0.12 billion years old” which assume (c) is true. Actually, such statements are really conveniences, because they allow us to apply time markers to various stages of the universe’s evolution.

The result of all this is that we are face to face with a dilemma. Curiosity and wonder cause us to yearn for answers that our current state of knowledge can’t gratify. Worse, we may never have gratification, because we are bumping up against the limits of what technology and even the laws of physics themselves can help us answer. The most powerful telescopes in the world can’t see all the way back to the beginning, if there is one, of the universe (remember that in looking at objects further and further away in space, the time it takes for the light to reach us means we are looking further and further into the past). The most powerful particle accelerators we have built can’t come close to reproducing the earliest fraction of a second of the universe’s existence. Even the theoretical / mathematical approach, through it has paid its share of dividends in nuclear physics (it is how Murray Gell-Mann predicted the existence of quarks for example), might not get us there. It is as though we keep creeping closer and closer to our goal, yes, but we can never actually get there, however patient and persistent we are.

Still, the ability to trace back the evolution of the cosmos back 13.73 ± 0.12 billion years is a remarkable feat, one of the most remarkable in the history of science, even if we struggle to squeeze the previous trillionth of a second or so out of our cosmic clock. We are talking of a time long before our solar system existed, indeed long before there were any stars or planets or galaxies or kinds of structures we see in the universe today. What we can say is, however, is that the primordial seeds of all these structures, including ourselves, must have somehow existed in the super-hot, super-dense soup of quarks, gluons, electrons, neutrinos, photons, and what else have you which constituted the universe – or at least our universe – at that time. How those seeds of so long ago became the reality we experience around and within us today is a fantastic tale, only a fraction of which has been worked out to any detail.

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So much for ultimate beginnings. Let us jump forward to more mundane affairs. I suspect that most people, if asked what the early Earth was like, would probably think of dinosaurs roaming its landscapes, and their reptilian cousins filling the air and the oceans. Some would even think of “cave men” (not all early humans lived in caves, of course) hunting wooly mammoths and other prehistoric creatures. I hope these statements don’t sound condescending, because they aren’t meant to be. Rather, they are meant as cautions regarding our sense of time, particularly our sense of so-called “deep” time, that time scale in which biological, geological, and cosmic evolution reveal their full and wondrous workings. Time of this magnitude overwhelms our imaginations. We simply cannot, however hard we try, conceive of a million years. Even a thousand years – a thousandth of that million, and the approximate distance between Middle Age Europe and today – defies our intuitive sense of time. Actually, as Richard Dawkins points out in The Blind Watchmaker this is not only unsurprising but exactly what we should expect: our intuitive sense of time is the result of the way our brains are wired, and the genes that have wired them have been selected by evolution to give us good, gut-level grasps only of events that take from significant fractions of a second to decades to happen. Any event much shorter than a second or longer than a hundred years or so fall outside of the range of our intuitive time sense, and we shall have a hard time conceiving them. This is why a thousand, a million, a billion, and a trillion years all feel pretty much the same to us, although there is a thousand fold difference between each pair, thousand to a million and so on. Again, as Dawkins has noted, this is probably one of the main reasons for most of the people who reject evolution; they simply cannot imagine the time scales involved, and therefore seriously underestimate what is and isn’t probable during them.

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Typically, this is where most authors of books dealing with deep time try to come up with some kind of scale which makes these times more intuitively manageable. The scale often relates time to distance; so that for example the age of the universe may be represented by a line stretching from Los Angeles to New York City, or something like that. The trick in using this analogy is in avoiding scales which already defy readers’ imaginations at one or both ends; I, for one, am not sure I can intuitively grasp the three thousand mile LA-NYC distance effectively. This of course is because our brains have also been selected to have good, gut-level grasps of distances as well as times, and three thousand miles almost certainly falls well outside of that range as well.

On the other hand, too small a scale, while allowing us to grasp its full length, can be too short to let us sense the fractions of that scale we wish to deal with. For an example of this, a universe timeline only a mile long would put our human lifespans in a fraction of a thousandth of an inch range; most of us, I suspect, find that just as hard to fathom as the LA-NYC distance.

What we want is a scale that is neither too large in its full range, nor too short in the fractions of that range we wish to work with. The scale I’ve chosen to work with seems pretty workable to me. What I propose to do is simply scale all times down by a factor of a billion. I am also leaving it as a time scale, rather than converting it to distance as many people do. In this scale, therefore, the universe is about 13.7 years old. As human beings in the real universe generally live between two and three billion seconds (there are 31,556,926 seconds in a year, or a billion seconds in 31.688765 years), our average lifetimes are reduced to between two and three seconds using this scale. Events thus appear pretty manageable at both ends of the continuum, or at least they do so for me.

If we take this moment, now, December 18, 2008 as I write these words, as the end point of our scale, then the universe “began” (recall my cautionary statements earlier about the beginning of the universe) in early April of 1995. Relating that to my own life, I was thirty-eight years old then compared to fifty-two today, my 21½ year old daughter was nearing her ninth birthday, and my 14½ year old son was only a baby, not yet taking his first steps yet. President Bill Clinton was in his first term, it was about four years after the fall of the Soviet Union, and the terrorist attacks of 9/11/2001 were still over six years in the future. I can relate a lot of other events of that time in my life, and no doubt so can the reader (unless you are a teenager or younger).

There are numerous ways we can proceed here. For example, the expanding universe became transparent – that is, it cooled off enough for the first atoms to form, allowing electromagnetic radiation to decouple from matter and stream freely through space in what is now called the cosmic background radiation – about 3½ hours later on that April day, and the first galaxies that we can detect with our most powerful telescopes would have formed about a year later, in early 1996. We don’t know with certainty when our own Milky Way galaxy condensed from intergalactic gas and dust, but it must have been well before the creation of our solar system 4½ years ago, in June, 2004. This is because our sun is a so-called “first generation star”, one heavily composed from the ejecta of earlier, massive stars which exploded in supernovae and seeded interstellar space with all the elements up to uranium (thereby allowing the sun to have terrestrial planets like Earth).

If we restrict our timeline to events that happened on Earth, then the first fossil traces of simple “prokaryotic” (bacteria or archea) cells appear as either rare microfossils or biochemical traces between 4 and 3½ years ago, although recent hypotheses about early Earth could mean life began sooner. Eukaryotic cells, which are larger, more complex cells which comprise all animals, plants, and fungi today, evolved from prokaryotic cells at around somewhat more that half that distance from the present, or around two years ago, and the first, unequivocal albeit very simple multicellular organisms appear, along with sex, approximately a little over a year ago, although this is uncertain because such organisms contained no hard parts (shells, skeletons, etc.) and would have left few fossils.

At this point, let me backtrack a little. Earlier I mentioned how most people probably think of dinosaurs, or even early humans aka cave men, as living on the early Earth. We begin to see now just how potent a testament to our poor intuitive grasp of time that is. So far I’ve covered about three-quarters of the Earth’s history, and over ninety percent of the universe’s and nowhere have dinosaurs or early humans been mentioned. In fact, we still have some considerable chronology to cover before we get there.

Scientists, as they so often do whatever their field of specialty, have divided Earth’s history into a number of time slices called eons (technically, an eon is a billion years, so it is used only as a rough approximation here). These are, from oldest to most recent, the Hadean eon, covering the time between Earth’s formation and 3.8 billion years ago; the Archeon eon, when life unequivocally first began, lasting from 3.8 billion years ago to 2.5 billion years ago; the Proterozoic eon, from 2.5 billion to 542 million years ago, covering the evolution of eukaryotic cells and the first multi-cellular organisms; and the Phanerozoic eon, which takes us from the end of the Proterozoic to the present. Each of these eons begins and ends with some important developments in the evolution of life on our planet: the first appearance of life, the first eukaryotes, and so on (the burying of the first multicellular organisms and sex in the middle of the Proterozoic seems to be the major exception to this schema).

On our 10⁹ : 1 scaled down history of the universe, the Proterozoic Eon lasts from two and a half years to six and a half months ago. The last three and a half months (starting from ten months or 850 million years BP) of this epoch are of immense importance to biologists, geologists, and paleontologists because it includes a series of events which may have given rise to the world we know today, teaming with highly complex, diversified multicellular organisms – such as ourselves – which dominate almost everywhere we look.

The first such series are a sequence of serious ice ages, lasting from 850-800 million (ten months) to around 630 million (seven and a half months) ago. There is considerable controversy over just how severe these ice ages were; the phrase “Snowball Earth” has been coined by those scientists who believe virtually the entire planet was entirely frozen over, right down to the tropics, while critics of this admittedly dramatic picture believe the planet came nowhere close to such extremes – the phrase “Slushball Earth” has been used by a number of said critics. Other scientists dispute the timing as well as the extents of the ice expanse. It appears also that these ice ages were interspersed with periods of unusual warmth. This is because greenhouse gasses such as carbon dioxide (CO₂), methane (CH₄), and sulfur dioxide (SO₂) belched from active volcanoes would have built up in the atmosphere during the ice ages, yet the extremely cold, dry atmosphere would have been unable to precipitate them out; when rising temperatures caused by this CO₂ / CH₄ / SO₂ driven greenhouse effect finally did melt the ice there might have been temporary “Hot House Earths” until the excess gas was finally removed.

Whatever the exact scenario, these large climactic swings must have had devastating effects on Earth’s biota of the time. We may be quite fortunate that all life was not completely and permanently extinguished. Certainly, many species would not have been able to cope with the prevailing conditions and did become extinct, while those that did survive probably stumbled upon various adaptations which natural selection would have favored. In short, the Snowball / Hot House Earth period probably was a crucible in which evolutionary pressures would have been much greater than at almost any other period in Earth’s history – a biological ice house / smelter from which those who emerged would have many improvements over those who went into it. This is a somewhat speculative statement, but it is a reasonable one. The fact that the first truly complex multicellular organisms appear in the fossil record only a few million years after the end of the Proterozoic ice ages (about two weeks in our timeline) – the so-called Ediacaran fauna of soft-bodies animals – lends support to it.

Let’s stop, catch our breaths, and take stock of where we are and how far we’ve come. In mentioning the first appearance of the Ediacaran fauna we are standing somewhere between 600 and 580 million years BP. That is about seven months BP in our scaled-down timeline. Given that Earth first condenses from the solar nebula 4½ years, or 54 months, ago on this timeline, we have already covered 1  47/54 = 87% of our planet’s history (or, that the universe begins 13.73 years or 165 months ago, 1  157/165 = 96% of its history). By this reckoning, even Ediacaran animals are the new neighbors on the block, although they don’t hang around for long: by six and a half months ago or 86.5% of Earth’s history they have vanished forever.

Dinosaurs? Early humans? Not even close yet.

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As a child, probably my second most favorite activity, after star gazing, was fossil hunting. There was a small creek which ran very close to the house I grew up in, and from time to time I would spend a few hours at one of the sandy banks and rock outcroppings along the beach, turning over stone after stone in hopes of find one with the outlines of some ancient life form on it (those that didn’t I would practice stone-skipping with if I could find stones flat enough). Mind you, I didn’t have a fossil collection, not in any kind of formal sense; I just kept whatever I found of interest in the various places I squirreled stuff, taking them out occasionally to look at and wonder about. I wouldn’t even hazard a guess as to where any of them are now; most of them are probably back in the ground I liberated them from, hopefully to be re-unearthed by future generations.

I don’t remember if the connection between the two pastimes, star gazing and fossil hunting, ever occurred to me back then, but it is quite obvious now. Both are attempts to peer into the past, to learn about what was, not just a few years or even centuries but thousands and even millions of years ago. There is something about the vastness of deep time, like deep space, that is paradoxically both very intimate and infinitely far away at the same time; it is, I sometimes suspect, rather like being with someone we have known and loved for a long time, but still realize we don’t know very well.

I didn’t become either a paleontologist or an astronomer because, as I have already confessed to, I’m too much of a scientific dilettante, and too lazy I must also add, to put in the time and effort or endure the tedium that being a professional in these fields requires. So I don’t hunt for fossils anymore; I would no doubt chuck them anywhere convenient, something that I now know but my child self didn’t is akin to blasphemy. Let someone who will treat them with appropriate respect discover them.

The very idea of a fossil is a fantastic one, one that makes us shake our heads in near disbelieving wonderment when we think about it. Think of all the many quadrillions of living things that must have lived and died on this planet. Despite such numbers, that any of them should have had their hard parts (and sometimes soft parts) mineralized into or left impressions in rock, and then be exposed to human eyes millions of years later by weathering or geological processes is, I think, amazing enough. But to in addition be discovered by scientists who study them and use them to piece together so much of the story of life on Earth as they have, is one of the most remarkable accomplishments of science. For me it is certainly well up there with the discovery of the laws of physics or the elucidation of the details of biological heredity.

I have paused in our cosmological timeline to talk about fossils because for most intents and purposes this is where life really begins. True, we do have fossils and fossil traces and other biochemical markers in rocks older than 540-550 million years ago (six and a half months on our timeline) but they are much rarer and difficult to find because before this time few if any living things possessed hard parts to leave behind when they died. This is the start of the Cambrian period of our current era of life, the Phanarozoic eon; this is the beginning of many animals possessing shells or exo or endoskeletons which can mineralize after the animal’s death or leave clear impressions in rock.

One of the most fascinating – and scientifically challenging – things about the Cambrian is how quickly this evolution and radiation of creatures with hard parts occurs. Quickly on the geologic scale that is; within a few tens of millions of years at most, or about a week on our timeline, most of the major phyla (large groups of life, such as vertebrates, arthropods, mollusks, etc.) have made their first appearance in the fossil record. This period is even often termed the Cambrian Explosion in recognition of its extreme rapidity, although of course by human time standards it is still an immense stretch of time, well, well beyond anything we can intuitively grasp. It is as though the speed of evolution had been stepped up by an order of magnitude or more for a good several tens of millions of years or more. Scientists are still debating the cause of the Cambrian Explosion, with some arguing that it really wasn’t really an explosion at all but more of an artifact of the fossil record. Time, if the pun can be pardoned, will tell. Either way, by some 500 million years or six timeline months or so ago almost all the major animal body plans had been laid down and are ready for evolution to elaborate and sculpt them into all the animal species found on Earth today. An Earth that is about ninety percent of its present age, or ninety-seven percent of the universe’s. And yes, we still have a way to go before the first dinosaurs appear.

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I hope that by now you have started to get at least some feel for the overwhelming immenseness of geologic, or more, of cosmic time. During the period we have been covering so far, somewhere around a couple of billion stars have been born, lived, and perished in our Milky Way galaxy alone, and probably over a billion trillion in the universe as a whole, a universe that has expanded from something much smaller than an atom into an empire of galaxies, galactic clusters, and galactic superclusters spreading over tens of billions of light-years of spacetime. It all begs the natural question: have any other civilizations preceding our own come into existence, and perhaps went extinct, in all this enormity? Have any other minds even puzzled over the questions we puzzle over now? It seems so odd that the answer to this question is that we simply don’t know, and may never know, however hard we search for it.

Based on what we do know, our own existence was not even remotely close to guaranteed at the end of the Cambrian, that half billion years / six months ago. The fact is, even today, almost one hundred and fifty years after the publication of the Origin of Species, we still don’t know in any detail why some species lines survive while others go extinct. We comprehend in broad brushstrokes about natural selection and adaptive complexity and the competition for survival and reproduction, yes; but we can’t point to any fossil in a geologic strata and say for sure why it does or doesn’t exist in the strata directly above or below it. There are general trends in the fossil record that can be followed and so offer hope for better understanding: an increasing number and diversification of species and genera (punctuated by mass extinction events which we will come to shortly); long term increases and decreases in the sizes of the largest species; a general overall though not perfectly steady trend towards increasing complexity and intelligence, assuming that cranium versus overall body size is a good indicator of intelligence. We can, if we squint our eyes tight enough and apply a liberal enough dose of imagination and wishful thinking, perceive humans or something like humans eventually rising from the fray. But we don’t really know, whatever we privately, or publically, believe.

The biggest monkey wrenches thrown into our hopeful perception of progress from the Cambrian onward are the mass extinction events that pock-mark the fossil record like shotgun blasts from a drunkard. There are five recognized major ones during Phanerozoic eon (the criterion for being major is that over fifty percent of existing animal species were killed off), along with a myriad of smaller events. The most important effect of these events is how they often drove many hitherto successful species, genera, families, and even entire orders into extinction, essentially “clearing the slate” so that new kinds of animals could rise to prominence. Life on Earth today would be much different had they not occurred. We, for one, would certainly not be here to discuss them. With almost equal certainty neither would the dinosaurs, whose rise and fall appear to be the result of three of the five major events.

Let’s return to our timeline, where we left off six months, or 500 million years ago, bearing in mind again that we are almost at ninety percent of Earth’s present age. If we fast-forward to half that distance in the past, three months / 250 million years ago, we find that our Cambrian beginnings have covered quite a bit of ground towards the planet’s current biota. The oceans, lakes, and rivers are filled with fish, many of which are indistinguishable from fish of today, although the proportions of the different classes are different; there are more lobe-finned fishes (the ancestors of land animals) than today. Many of the land and water arthropods are also fairly modern-looking, one of the obvious exceptions being the trilobite, an ancient arthropod reaching back to the Cambrian but whose days are severely numbered by this time. Another difference is that some of them grow to amazing sizes; there are, for example, dragonflies with wing spans close to a meter across. The land is already populated by a wide variety of amphibians and reptiles, although especially for the latter, they don’t resemble those of today very much at all; some of the latter are the so-called mammal-like reptiles, named for exactly the reason you imagine, and indeed all modern mammals are descended from a lineage of them. Many ferns, mosses, and conifer trees also fill the landscape along with other plants, though none of them sport flowers or are pollinated by insects or birds – for that matter, there are no birds or other flying vertebrates to pollinate anything. As for the state of the world, much of its climate at this time is hot and arid, and all of the major land masses are joined together in a single, super-continent named Pangaea, the center of which is possibly the largest desert ever to have existed in Earth’s history.

It was on this world that what has been called the Mother of Mass Extinctions then happened 250 million / three months, the Permian-Triassic, or P-T, extinction event. Over the next several million years (about one or two days on our timeline) the great majority of species in both land and marine environments vanish from the fossil record, leaving no descendants. Estimates of the total carnage are as high as 90-95% of marine species, and 70% of land. Of most important for this discussion were the extinction of most of the mammal-like reptiles (excepting the one that gave rise to mammals, of course), leaving room for the rise of the group of reptiles called archosaurs, which appeared either somewhat before or after the extinction, depending on their exact definition. Whatever definition is accepted, the archosaurs are the ancestors not only of modern crocodiles and birds, but also the dinosaurs and pterosaurs (the flying reptiles of the dinosaur age), and the marine reptiles which would come later.

The first true dinosaurs appear in the fossil record some 225-230 million years ago, in the middle of the Triassic, the first period of the Mesozoic Age, or age of reptiles. And thus finally we are here, a mere two and a half months ago on our timeline, with our planet being 95% of its current age. So the dinosaurs aren’t ancient at all, but are more like our next door neighbors in time. The next major extinction event, at the end of the Triassic 205 million years ago, cleared out most of the rest of the dinosaurs’ competition and led to their being the main land animals on Earth for the next 140 million years, until they themselves met their end in the most famous (but not largest) extinction event of all, the Cretaceous-Tertiary or K-T event, 65 million years / 24 days / 1½% of Earth’s age ago. Indeed, looked at this way it seems like just yesterday that Tyrannosaurus Rex and its cousins spread their terror across the land, making the world of Jurassic Park almost sound plausible.

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The causes of mass extinction events are still strongly disputed in the scientific community. One of reasons for this is that there are many possible contenders for causes, geologic, climate-related, or astronomic; so many, in fact, that we probably should count ourselves absurdly fortunate that life was never completely wiped out by one or a combination of them by now – assuming that that there isn’t something other than fortune going on here. Over the last 20-30 years, however, two particular contenders have come to acquire particular interest: asteroid impacts and massive volcanism known as flood basalt events. Interestingly, although both scenarios are very different in the events that begin them, the consequences to Earth’s biota are due largely to changes they cause in the planet’s atmosphere. The impact scenario, which was first hypothesized for the K-T (dinosaur) extinction by Alvarez et al in 1980, proposes that a large (5-10 miles across) asteroid struck Earth 65 million years ago, injecting so much dust, water vapor, soot, and ash into the atmosphere (the latter two from massive forest fires caused by burning debris from the impact) that the amount of sunlight reaching ground level would have been seriously reduced for as much as several years. The results would have been severe cooling and reduction in photosynthesis, killing all those plants and animals that could not adapt to these extreme changes.

The Alvarez hypothesis is supported not only by geologic data such as high iridium concentrations and shocked quartz in the K-T boundary stratum, but also by the discovery of an impact crater of appropriate the right size in 1979 just off the Yucatán peninsula. Despite all this, the hypothesis is not without its problems, one of the main ones being an alternative which might be better (another problem is that there are known large impacts in the geologic record that are not associated with mass extinctions). This alternative is the massive volcanism / flood basalt event hypothesis.

Volcanic eruptions occur in different scales and varieties. Some, like the volcanoes of Hawaii, involve a more-or-less steady flow of lava from an underground magma reservoir over a long period of time. Others are explosive, releasing large amounts of hot ash and gasses, along with pyroclastic flows and lava and rock “bombs” over a relatively short time period. Mount Vesuvius, which destroyed the Roman cities of Pompeii and Herculaneum in a 79 AD eruption, is one example of this latter type of volcano. Another is Mount Tambora in Indonesia, whose eruption in 1815 was probably the largest in history: not only did it outright kill over 71,000 people, it injected so much gas and dust into the atmosphere that there was significant global cooling over the next several years, killing many more from famine due to crop failures.

I mention Tambora not because it was so horrific a catastrophe, but because compared to many eruptions in our planet’s geological history, even its recent history, Tambora was a firecracker which possibly didn’t result in a single species’ extinction. When it comes to serious volcanic eruptions once again we should breathe a sigh of relief and count our lucky stars. And worry about what could happen in the future.

If you want an example of what not only could be but one day will be, though nobody knows when, take a trip to Yellowstone National Park. While you are admiring the many geysers, hot springs, fumaroles, and steam-belching mud pots, and standing in awe of the massive yellowish volcanic tuffs whose color gives the park its name, imagine what lies under your feet that is causing all these natural splendors. What you are standing on is an enormous volcanic caldera, one approximately 1500 square miles in extent (the Tambora caldera is about 20 square miles), which itself overlays a magma chamber of comparable size. The caldera is the result of a colossal volcanic eruption, or “supervolcano”, some 640 thousand years ago, which was orders of magnitude larger than the 1815 Tambora event. If such an eruption were to happen today, which it very well could, the human death toll would be easily in the millions if not tens of millions, from both direct and indirect (climatic, etc.) causes. And there have been eruptions of comparable magnitude that occurred more recently. The Lake Toba caldera on the Indonesian island of Sumatra, comparable in size to Yellowstone, exploded around 70,000 years ago in an eruption so large that it may have almost caused all human species existing at that time to go extinct.

Yet Yellowstone and Toba are nowhere near the upper limit when it comes to volcanic events on this planet. Flood basalt events involve single or multiple volcanic eruptions (of any type) so enormous that they cover up to a million square miles and more of Earth’s surface with lava, to a depth of a mile or more. Such eruptions can dwarf supervolcanoes as much if not more than the latter dwarf any historic volcanoes. Actually, a good example of flood basalts is the maria, or “seas”, on the moon. These are the dark, relatively crater-free, regions which cover much of our satellite world (I should say the half of that world that always faces us due to tidal locking; the “far” side of the moon is almost devoid of maria). The two largest of these events on Earth, within recent geologic history, are the Deccan flood basalts of India and the Siberian flood basalts. I don’t want to even speculate what would happened if either of these events occurred today, because what is so interesting about them is their timing: the Deccan basalts were laid down approximately 65 million years ago, and the Siberian basalts around 250 million years. Both dates coincide with what are probably the two most important mass extinction events: the Deccan with the K-T event which finished the dinosaurs, and the Siberian with the P-T event, the largest extinction event in the geologic record. If you find it difficult to believe that such timing is just coincidence, you have a great deal of company, including me.

* * *

For myself, the on-going debates about the causes of mass extinctions is wonderful and exciting because it shows science, and the people who devote their lives to it, at its best. The combination of simple human inquisitiveness, wide-eyed imagination, the struggle to avoid dogmatism, and hard-nosed skepticism based on details has no equal in any other form of human endeavor. We see an enormous mystery, we open our minds as wide as lotus blooms to come up with possible solutions, but the solutions we come up with must run the gauntlet of data (often incomplete, unclear, and contradictory), experimentation, calculations, and competition from alternatives that other minds as bright as our own have dreamed up while we were busy proving our own ideas. And then, just when we think we’re on the verge of having it all figured out, someone or something else – usually new data – comes along to re-ignite the controversy.

Until 1980 the whole field of explaining mass extinctions was, from what I can tell, rather moribund. It wasn’t that there was a dearth of ideas on what could wipe out such a large proportion of species over a short period of (geologic) time. The two main problems, again from my own reading, is first, a lack of detail in the fossil record, in terms of exactly which species went extinct and exactly when they did so – for example, had an extinction occurred abruptly or over several millions years? – and second, the difficulties in determining what kind of evidence a certain kind of event would leave – an example in this case would be, if a nearby supernova (exploding giant star) had caused the extinction event, what markers in the geologic record would reveal it? The result was that the extinction events looked more like the random acts of a god or gods instead of anything that could be explained scientifically. Many scientists didn’t even want to think about them, even.

The main effect of the Alvarez impact hypothesis, more than anything else if I am reading history right, has been to bring the spotlight, not only of publicity but of serious scientific thinking on the whole subject of explaining mass extinctions. What makes this achievement all the more amazing was, it wasn’t what the Alvarez’s were trying to do at all! Many people by now have heard the story of how they stumbled upon anomalously high levels of iridium in samples of K-T boundary clays, inferred a large asteroid impact from that single fact, then suggested that said impact might be the reason for the dinosaurs’ mysterious vanishing act 65 million years ago. What most people probably don’t know is how much resistance the impact hypothesis met among paleontologists and biologists at the time, many of whom argued that the fossil record showed a gradual decline of dinosaur numbers and diversity for millions of years leading up to their final extermination – data that the impact scenario decidedly does not predict – and that in any case it was hard to reconcile the pattern of extinctions with the consequences of a large impact. What is more interesting, to me at any rate, is how these objections didn’t go away even as further evidence – shocked quartz, soot from mass fires in the boundary clays, and the discovery (or re-discovery) of the 65 million year old “Chicxilub” crater in the Yucatan peninsula – appeared the cinch the case for an impact-caused extinction.

Scientific analogies are a bit treacherous, but in some ways this one reminds me of Neils Bohr’s work on explaining the hydrogen atom in 1913 with the then new ideas coming out of quantum theory: it was brilliant and original, predicted properties of atomic hydrogen perfectly such as its spectral line series, was critical in the development of atomic theory, and rightfully earned Bohr his fame and Nobel Prize, but …but that was all it did. It couldn’t predict the properties of any other atom or molecule, nor did it offer any explanation for why electron orbits should be quantized. It was an absolutely necessary and essential step, but that’s all it was, a step.

By the 1990’s impact theory was so in vogue that some scientists were attempting to explain all extinction events with them. It was even postulated that the sun had a stellar companion, suitably dubbed Nemesis, that was too dim to have been detected so far and which had a highly elliptical orbit that brought it close to the inner solar system once every 26 million years or so, disturbing enough comets in the Oort cloud and / or Kuiper Belt to rain destruction down on Earth and other planets. The 26 million year cycle in extinction events didn’t hold up well under statistical analysis, however, but that didn’t stop people from finding iridium anomalies and shocked quartz and other geologic evidence associated with the big die-offs.

Still, a lot of the paleontological evidence just could not be made to fit simple impact hypotheses, leading some scientists to look for other causes. And here I think they were helped by yet another one of those convergences like those that Schmidt mentions in his book. The 1990s and 2000s were times of increasing scientific work on the effect of anthropogenic greenhouse gasses on Earth’s climate, and the possible implications of quick temperature rises of around 5° – 10° C or more, rises that seem plausible given our current state of knowledge. One of these implications involves the release of a large amount of methane, another potent greenhouse gas, from methane “clathrates” or “hydrates” lying on the ocean floors (these are methane deposits held in an essentially frozen state in water ice by the cold and great pressure of the ocean depths; once brought to the surface they disintegrate rapidly, releasing the methane into the atmosphere). A large scale release of this methane, which exists in enormous quantities on the bottoms of northern and southern oceans, could lead to even more drastic, short-term warming of the planet.

This issue led to a reexamination of the possible consequences of large-scale volcanic eruptions on our planet’s climate, in particular the Deccan and Siberian flood basalt eruptions which are by far the largest over the last 500 million years ago – er, six months on our timeline, if anyone is still counting. Eruptions do release large quantities of various gasses, mostly water vapor (H₂O), carbon dioxide (CO₂), methane (CH₄), sulfur dioxide (SO₂) and hydrogen sulfide (H₂S); all of these are greenhouse gasses, though some, like SO₂, can lead to cooling also due to the sulfate aerosols they often form; in addition, H₂S can also erode the ozone layer in large enough quantities. We’ve already seen how a large eruption in the historic record, Tambora in 1815, had serious consequences for Earth’s climate for several years. What might enormously large eruptions on the scale of the Deccan and Siberian lead to?

It isn’t an easy question to answer, in part because it is difficult to determine the quantities of volcanic gasses released in these eruptions and the time period(s) they were released over, let alone the global effects of such releases. But by the mid 2000s some scenarios had been worked out which showed how these events could have played a major role in the P-T and K-T extinctions which coincided with them. Also, by then evidence for these scenarios had been found in the geologic and fossil records.

What follows is worrisome to me because of what it might imply about our current problem of anthropogenic greenhouse gas warming. In my chapter on the future, I placed man-made environmental catastrophes aside in considering our own future evolution while stressing that something like Homo sapiens and our technological civilization on this planet is a gigantic experiment which may never have been played out in the universe before (and may never again), so we don’t know how it is really going to turn out. There are simply too many unknowns, and trying to wade through all possibilities is a Sisyphean task a hundred books wouldn’t be enough to cover. But if the connection between mass extinctions and massive flood basalt eruptions proves out to be true, what it suggests about our current greenhouse warming is sobering. We may need to take much more drastic steps than we are taking now in order to prevent any significant warming.

What makes the flood basalt driven mass extinction hypothesis especially interesting is that it brings together a sequence of different environmental triggers to accomplish its devastating effects. First, large scale emission of greenhouse gasses, such as H₂O, CO₂, CH₄, SO₂, H₂S (the last gives rotten eggs their odor), and others warm not only the atmosphere over a period of thousands of years or more, but also the upper layers of the oceans and other bodies of waters. Note that as mentioned, this warming may have released large amounts of methane (CH₄) from methane hydrates on the ocean floors, further exacerbating this warming. As warming water reduces its ability to dissolve gasses, reduced O₂ in the oceans leads to widespread anoxia, which in combination with increased acidity due to CO₂ absorption, the direct effect of killing off many organisms in these layers followed. The indirect effect of reduced O₂ / increased CO₂ is far more insidious, however. In different areas of the ocean and some seas (the Black Sea of today is a well-known example), dissolved O₂ only reaches a certain depth; the waters below this depth, known as the chemicline, support only anaerobic organisms, some of which are bacteria which produce copious amounts of H₂S. This H₂S normally never makes it to the surface, but the anoxic waters and die-offs of aerobic organisms during the flood basalt events may have resulted in the H₂S producing bacteria proliferating and the chemicline rising to the surface, releasing large amounts of this gas into the atmosphere. The effects of high concentrations of H₂S in the atmosphere would be catastrophic for most land dwelling organisms. Not only is this gas directly toxic, more so even than the hydrogen cyanide (HCN) used to kill concentration camp prisoners in Nazi Germany, it is also light enough to rise into the stratosphere, where it would poison the ozone layer, allowing in higher levels of lethal ultraviolet light from the sun.

If the flood basalt / greenhouse warming / ocean anoxia / H₂S producing bacteria increase scenario is correct, it should leave certain evidence in the geological / fossil record. And indeed, for the P-T event we do find multiple forms of evidence, in the form of biomarkers for these bacteria in oceanic sediments, in lower oxygen levels in the atmosphere, in the patterns and types of extinctions, and in fossils showing the effects of increased ultraviolet radiation. So it would appear that the Siberian flood basalt events hypothesis of P-T extinctions is well on its way to being confirmed. But what about the effects of the Deccan floods basalts on the K-T extinctions 65 million years ago? The scenario is essentially the same, but can they too account for that event, with or without a large impact?

The Deccan flood basalt caused K-T extinction was actually first proposed by Dewey McLean more-or-less concurrently with the Alvarez impact hypothesis. Although initially overshadowed by the more dramatic image of an asteroid striking Earth and the possible consequences of such an event, this may be due more to yet another convergence in scientific thinking; for this was about the same time that the “Nuclear Winter” hypothesis was being popularized by Carl Sagan and other scientists, and the parallels between the two ideas were undeniably striking. Sagan’s Nuclear Winter hypothesis claimed that even a relatively small nuclear war (relatively truly being a relative term in this case) could release into the atmosphere so much dust and ash and soot from massive firestorms that photosynthesis could be blocked for up to several years and the planet thrown into a deep-freeze, very much like the results of a large impact. Naturally, the re-discovery of the Chicxulib crater also lent a great deal of support to the Alvarez impact theory.

In the end, scientific hypotheses rise or totter and fall based on physical data, in this case the data being the precise timing of the K-T extinctions compared to that of the Chicxilub impact and the Deccan flood basalts. And what appears to be happening over the last ten years or so as far as I can see is that the timing is coming to favor the flood basalt hypothesis better and better. The Chicxilub impact may have actually occurred several hundred thousand years before the final extinction K-T extinction pulse. Of course, it is possible that the impact did still play an important rule, in driving some species closer to extinction. But it is becoming difficult, at least from my read of the controversy, to doubt the central importance of volcanism.

* * *

It’s high time to return to our timeline, although all this talk about mass extinctions and their possible causes leaves me hungry for more. We left off at the end of the dinosaurs, the K-T event, some 65 million years / 24 days / 1½% of Earth’s age ago if I may reemphasize just how recent the dinosaurs are in Earth’s history. We have entered the Cenozoic Age, or age of mammals. The first mammals actually appear in the Triassic, along with the dinosaurs, but until this point they have remained relatively small, mostly nocturnal animals, who eked out their existence in ecological niches the dinosaurs, for whatever reasons, never penetrated. The extermination of their dominating cousins in the K-T mass extinction finally allows the mammals to multiply, diversify, and grow into those now empty niches (along with the dinosaurs’ closer cousins, the birds). Remember that on our timeline Earth and the solar system condensed 4½ years ago and the universe began almost fourteen. We have come a long ways indeed.

How far back can we trace our own ancestors, genus Homo and the australopithecines or upright-walking apes they evolved from? No evolutionary line can be said to start anywhere, of course, but we can identify certain points as being of special importance. For humans, this is probably the split between the human and chimpanzee / bonobo evolutionary lineages which, according to a combination of genetic and fossil evidence, began somewhere between six and seven million years ago, somewhere in Africa. This is one tenth the distance back to the K-T extinction, so we are speaking of about two and a half days ago on our timeline or 0.15% of Earth’s total age.

What about modern humans? This depends on your exact definition of modern. Humans that look essentially modern, but from an intellectual point of view probably weren’t there yet appear several hours ago, while those ancestors we would call fully modern probably about two hours before the present. These modern humans first leave Africa to colonize the rest of the world not much more than a half-hour ago, establishing the first proto-civilized settlements within the last four or five minutes. The rise of the modern industrial state takes to some thirty seconds before the present, and you, depending on your age, probably between ½ and 2½ seconds old, have another couple of seconds or so to go before it’s lights out – well, that may very well depend on how some of the predictions I made in the last chapter pan out. Very comforting, no doubt.

And now let us head into the more distant past, the earliest moments of the future, or what most people refer to as the Big Bang.

The giant lanterns of San Fernando, Asia's Christmas capital

By Al Gerard de la Cruz, for CNN

updated 10:19 PM EST, Mon December 23, 2013

 

San Fernando is the birthplace of the Philippines' giant Christmas lantern and home to the annual Ligligan Parul (Giant Lantern Festival). Each lantern stands about 20 feet high and features 5,000 or so lights.

San Fernando isn't just famous for its giant lanterns. The city's smaller parul sampernandus lanterns vaulted to cottage-industry status in the 1960s when they moved away from classic designs in favor of more colorful creations inspired by everything from psychedelic kaleidoscopes to batik textiles.

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STORY HIGHLIGHTS

• San Fernando dubbed "Christmas Capital of the Philippines" for its Giant Lantern Festival
• A giant parol -- Christmas lantern -- costs around US$11,300-15,820 to build
• Smaller, mass-produced 'parul sampernandus' can be found hanging outside homes all over the Philippines

 

SAN FERNANDO, Philippines (CNN) -- In skeletal form, they look like gargantuan honeycombs, rising 20 feet into the air.

 

They are the largest incarnations of the Philippines' parol, an eye-dazzling electric Christmas lantern that symbolizes the Star of Bethlehem.

 

In action they're truly a sight to behold. Each giant parol features a series of thousands of spinning lights synchronized by seven large steel drums -- the rotors.

 

When the parol spins, the rotor hits a row of hairpins, electrifying the bulbs.

Though smaller parols for household use have more latitude in covering, with choices like capiz shells and fiberglass, the giant lanterns usually stick to polyvinyl plastic.

 

Only 10 or so of the giant parols are produced a year to compete in San Fernando's Ligligan Parul, or Giant Lantern Festival. It has been held every December for the last 80 years in Pampanga province, about 75 kilometers outside of Manila.

 

It's this yuletide fervor for the nationally loved electric star that has lent credence to San Fernando's cachet as the "Christmas Capital of the Philippines." And likely even Asia.

 

More: 12 of the world's most spectacular Christmas trees

Ernesto 'Erning' David Quiwa, great-grandson of Francisco Estanislao, the first known parol-maker.

Five generations of parol makers

 

When visiting the San Fernando barangay (village) of Santa Lucia, the "home of giant lanterns," it's not unusual to behold a parol behemoth under construction right on the curb no matter what time of year.

 

The legend behind some of the biggest and best parols to come out of Santa Lucia in recent times is Ernesto 'Erning' David Quiwa, 66. Quiwa is the great grandson of the first known maker of the famed parol -- Francisco Estanislao.

 

On a recent visit to Quiwa's workshop, the parol master was busy overseeing the production of two giant lanterns. A worker was scaling the scaffolding to configure the 16-footer's 5,250 light bulbs.

Quiwa learned the craft from his uncles, one of whom in 1957 introduced the first parol rotor.

 

All five of Quiwa's children have ventured into the parol business.

 

"I never really taught my children," Quiwa says. "They learned on their own. Maybe it's in the blood."

Wondering About Our Place

To be, or not to be, — that is the question: —
Whether 'tis nobler in the mind to suffer
The slings and arrows of outrageous fortune,
Or to take arms against a sea of troubles,
And by opposing end them? — To die, to sleep, —
No more; and by a sleep to say we end
The heart-ache, and the thousand natural shocks
That flesh is heir to, — 'tis a consummation
Devoutly to be wish'd. To die, to sleep; —
To sleep, perchance to dream: — ay, there's the rub;
For in that sleep of death what dreams may come,
When we have shuffled off this mortal coil,
Must give us pause: there's the respect
That makes calamity of so long life;
For who would bear the whips and scorns of time,
The oppressor's wrong, the proud man's contumely,
The pangs of despis'd love, the law's delay,
The insolence of office, and the spurns
That patient merit of the unworthy takes,
When he himself might his quietus make
With a bare bodkin? who would these fardels bear,
To grunt and sweat under a weary life,
But that the dread of something after death, —
The undiscover'd country, from whose bourn
No traveller returns, — puzzles the will,
And makes us rather bear those ills we have
Than fly to others that we know naught of?
Thus conscience does make cowards of us all;
And thus the native hue of resolution
Is sicklied o'er with the pale cast of thought;
And enterprises of great pith and moment,
With this regard, their currents turn awry,
And lose the name of action.

William Shakespeare, Hamlet Act 3, scene 1, 19–28, circa.1600

 

Bolero by Ravel. An der schönen blauen Donau by Strauss. Rhapsody in Blue by Gershwin. Yesterday I listened to these three pieces of music, among the most beautiful and thrilling that I know of. Each has its own peculiar emotional impact, quite different from each other and yet all calling to me in ways that I am quite sure I could never put words to. I would give anything to know exactly what they have done to my brain and nervous system, which neurons they fire in which sequence, which neurotransmitters – serotonin? dopamine? – they released or absorbed in exactly the right structures and cells of my limbic system and cerebral cortex. There any many other wondrous pieces, from Beethoven to Mozart, to Benny Goodman, the Beatles, and Bob Dylan, and more which provoke the same questions.

There is more. Today I spent several hours driving along River Road in Bucks County, Pennsylvania. The road curvingly parallels the Delaware river in many places, in others the old Delaware Canal. It is carved out of the ancient rock which lines the river, and after several days of rainfall there are numerous small and medium rivulets and waterfalls cascading from the rocks, onto the road surface, and then across it to join the river and its way to the sea. Even without these added splendors, there are the carved, ancient rocks themselves, the trees and other wild flora of May, and the occasional animal, although I did not see any deer, or wild turkey, or any of the other wild animals that inhabit the woodlands on this particular day.

I know – I know as a scientist and as a rational human being – that what I have experienced these last two days would not be possible without millions of years of Darwinian evolution sculpting senses and a nervous system and brain to allow me to experience them. If I were but a rock, I would know none of them. Even if I were a cockroach, perhaps even a fairly evolved organism such a mouse … but because I am human – a sentient being – I experience all of it; all of what gives my life so much of its meaning.

And yet I am missing something.

It is a conundrum that has been known for centuries. One that philosophers have spun and spiraled in their minds to resolve, one that scientists in the relevant fields have grappled with to this day. Some think they have solved it. Yet I beg to differ. Some very straightforward thought experiments show how perplexing it is, how much it defies simple solutions. Theists and other religious pundits think that they solved it long ago, but I believe they are just as deluded. It is the problem of the soul.

What’s this? A scientist speaking of the soul?

Soul is perhaps a bad term. It conjures up the supernatural and the religious, and that, above all, is precisely what we are trying to avoid here too, as in all the previous chapters of this book. Better words are sentience and consciousness. Sentience is somewhat the better of these two because consciousness can refer to the mind and its workings, and what we want to grab hold of is that, however our bodies and minds work, there is an indisputable “we” inside, somewhere, that experiences those workings. This we has a more or less continuous existence, minus deep sleep and any periods of anesthesia or coma we might have had, going back to as far as … well, as far as we have memories of being.

We must concede an undeniable connection to mind and body, for, as I have been emphasizing, without these things there is nothing to experience, and sentience, the experiencer, must have something to experience if it is to exist. At the same time, however, as strong as this connection is, its strength does not reach to identity. Or at least I believe I have good reason for thinking it does not. Naturally, this only deepens the mystery; how can mind / body and sentience be at the same time the same thing and yet two separate things? The answer is that it cannot, yet we struggle mightily to resolve this seeming contradiction.

Don’t think there really are contradictory aspects to it? A few thought experiments should illustrate them nicely. Here’s one: imagine we have a machine, a lá science fiction, into which you step into one booth and out pops in a different booth, by some magical technology we shall in all probability never have, an atom-by-atom exact duplicate of yourself. This, of course, is the basic idea behind matter / energy beaming devices in Star Trek, and though I heartily doubt it will ever be accomplished, it seems at least possible in theory.

Well, what would you expect? Would you still be you? I expect all of you would agree that you would be. But how about this other “person” (I put this in quotes for a specific reason), stepping forth from the other booth? Would you be him / her as well? The answer to this question would seem to have to be an unqualified no, if only for the reason that there are no neural or any other connections between the two brains, which we are quite certain is absolutely necessary for you to experience being two bodies / brains at the same time. On the other hand, if you aren’t both you, then clearly you are the original you and the duplicate, although it would have all your memories, thoughts, and feelings, and be utterly convinced it was the real you, is just as clearly someone else. All this assumes, of course, that they are anyone at all and not a non-sentient simulacrum of you – which can only be true if making at atom-by-atom-duplicate of you is still missing something, something that we have no conception of as of yet. Either way, it isn’t the real you, however identical from a known science point of view it is.

Let me illustrate the problem a different way. I often read by those working in the fields of neurology, psychology, philosophy, and all the ways these fields can be conjoined (neuropsychology, cognitive science, etc.), that sentience is a consequence of brain action, an emergent phenomenon or epiphenomenon, one deriving from brain structure from the macroscopic to the microscopic, from the whole down to neurons and axons and dendrites and neurotransmitters and synapses and, well, and the laws of physics and chemistry as we know them. But there is something wrong with this picture, something, I think, that is actually quite obvious. It is that the Me (hereafter capitalized) that experiences being me does so now in a brain that is different from the brain it experienced being me yesterday, and even more different from the brain it experienced being me a year ago, and ten years ago, twenty, forty, fifty years … all the way back as far as I can remember being sentient.

All I know is this: Richard Dawkins’ statement in his preface to his most inspirational book The Blind Watchmaker, that “Our existence once presented the greatest of mysteries, but it is a mystery no longer because it has been solved,” is both true and false. It is true in the sense that Darwinian evolution, combined with the laws of physics and chemistry in this universe, neatly explains why at this moment some six point seven billion of us humans are running around on the surface of this planet, trying to survive and more, toward what consequences we are both uncertain and afraid of. But it is false in the sense of explaining why we billions experience ourselves doing so – assuming all of us do. Yes, yes, our highly complex and massive brains are part of the solution to this part of the mystery, but – well, is it enough?

* * *

This book being largely composed of scientific ideas and arguments, I wish like anything that I could present some for this most defiant of all mysteries. Alas, I find that after half a century’s worth of reading, exploring, thinking, and probing I cannot. Which leaves me in the position of wishing it would go away, so that it might not torment me, but it refuses to do that either. It is not, mind you, that I am afraid of dying and there being nothing left of either me or Me at all, perplexing and somewhat despairing I find that prospect to be; no, it is a true intellectual riddle, one that has defied all attempts not merely to solve it but even to adequately frame it. At least the reason for this can be stated in a straightforward way. The scientific method is an objective approach to reality, combining observation with hypothesis formation and testing, using both reductionism and holism when appropriate, in the never ending quest to determine just what is out there, all around us, to the ends of the universe. And it is a noble and even, dare I use the word, holy endeavor. But how and in what ways can this method be applied to the subjective reality of experience? How can it explain Me, or You, or any of Us? The answer I keep coming up with is that it cannot, cannot explain Me, You, or any of Us, solely because these are not objective phenomenon “out there” for us to explore and dissect. We can and should dissect and explore brains, and how they work, yes. But in the end, no matter how much we discover doing so I fear we will still not have solved the problem.

The conundrum is very real, and very serious, because we know of no method but science that can reliably reveal truths about reality to us. Mysticism and religion have no chance, in fact don’t even pretend to have a chance however many pseudo-arguments their proponents hurl at us. Yet science and reason can’t will or doubletalk the issue away, either, however.

* * *

Still, I have invited you to read a chapter about this subject, and merely repeating how dumbfounded I am about it is going to wear thin very quickly. So I must make some attempt(s), some approach(es), that have a plausible chance of leading us somewhere toward understanding.

And yet, I must proceed carefully. For example, certain writers, notably Roger Penrose (The Emperor’s New Mind) have suggested that sentience emerges from some of the properties of quantum mechanics. He has apparently even identified structures in the brain, known as neural microtubules, which he claims account for consciousness / sentience in a quantum mechanical brain; part of his argument, as I understand it, is that the human mind is able to solve problems in a non-algorithmic way. While I do not claim to fully understand his arguments, other writers, notably Daniel Dennett and Stephen Pinker, have challenged Penrose, saying that in fact all the things the human mind can do can be reduced to algorithms, albeit highly complex ones, without any consideration of the physical hardware (brains, computers, etc.) that these algorithms are executed in.

Personally, I find both approaches inadequate. We really don’t have any good reason to think that a sufficiently complex computer, one that can fully emulate all the properties of a human brain, will actually be sentient. On the other hand, the mysteriousness of much of quantum mechanics shouldn’t seduce us into thinking it has anything to do with the mysteriousness of our own awareness. That is an argument that sounds powerful on first hearing, but is really quite feeble. Lots of things in this universe are still mysteries, at least to some extent, but that is no reason to assume that they are interrelated simply because they are mysterious.

Of course, this doesn’t prove that quantum processes don’t have anything to do with sentience either, so I don’t want to grind my heel into any such speculations. It’s just that there are so many other mysteries as well. For example, why do so many of the natural constants of nature happen to have the value they have – the “fine-tuning” problem that vexes so many scientists? Why are there four fundamental forces, and why do they have the relationships they have? Why is the speed of light in a vacuum what it is? Why does Planck’s constant have the value it has? And so on. Some people, even scientists, note that all these, and other, constants, have values that are absolutely necessary for intelligent beings like us to exist, so perhaps there is some kind of higher intelligence or will that has ordained them so. Other scientists shake their heads at this kind of semi-mysticism and insist that, as we understand the cosmos and the laws of physics better, we will see how they had no choice to be what they are. Or perhaps there are many, many universes – perhaps an infinite of universes – so some simply had to turn out to have the right conditions; and of course we must be living inside one of those universes, or we would not be here to ask the questions and debate the answers.

* * *

My own personal feeling – and personal feeling is exactly what it is – suggests something else to me. A hundred years ago, at the beginning of the twentieth century, there were certain phenomena that stubbornly defied explanation by the then known existing laws of nature. The structure of the atom, as I have already mentioned, is probably the most famous. The conflict between Maxwell’s laws of electrodynamics and Newton’s laws of motion were another. As was the spectrum of blackbody radiation. The heat capacity of multiatomic gasses, and the photoelectric effect were a third and a fourth.

The solutions to these vexing problems involved, not merely new theories based on the existing laws of physics, but new paradigms, new ways of thinking, which opened up a new universe of laws and theories and hypotheses. These new paradigms were so challenging that many scientists have had a hard time accepting them even to this day, while those who do still sometimes puzzle and scratch their heads at what they really mean. Quantum mechanics. Special and General Relativity. Quantum Electrodynamics (QED) and Quantum Chromodynamics (QCD). The expanding universe and the notion of a beginning to everything, the Big Bang (though this is being challenged today in some quarters), and perhaps an end to all things, including time. The idea that space and time, matter and energy, are related in ways that you cannot treat them as separate phenomena. The use of mathematical group theory to explain the plethora of mass-bearing and force-bearing particles in nature, and the relationships between those particles. The idea of inflation in the very early universe, and how it might have led to many universes forming. And now of strings and supersymmetry.

Standing here, at the opening of the twenty-first century, I can envision a similar revolution in paradigms arising to answer the questions I address in this chapter. But as I said in chapter seven, looking at it now, it is science fiction. Perhaps even fantasy. For example, here’s one possibility: perhaps we will create a “super” brain, one composed of electronics and neuronics, that we can all interface with or even become part of. This brain might eventually spread throughout the solar system and then beyond, perhaps to ultimately fill the entire universe. Perhaps this is when humanity learns its meaning and destiny, and all questions are answered. Even those billions who have lived and died may be reincarnated into this star-spanning mind, and not just humans but every other sentient race that has lived and died, here and elsewhere in the universe.

Following this line of prognostication, maybe sentience is something like another property of the universe, one which requires certain conditions, such as those that occur in our brains, to manifest itself. But if it is that, a property, then what kind of property is it? It isn’t a force, or a kind of particle. Something interwoven into the fabric of spacetime itself? But how? And in what way?

* * *

Sometimes I wonder if the Buddhist concept of Maya and Enlightenment can help us here. Maya is the illusion we all experience, that of being separate beings, apart from each other and the rest of the universe, struggling to find our way through life, and ultimately dying in this illusion. The experience of Enlightenment is supposed to be one in which all Maya drops away and you are fully aware of being one with everyone and everything – an experience regarded as impossible to capture in words or any other physical medium. Yes, I wonder if Buddhism is on to something here. It would have to defy explanation by language or any other form of normal communication. One would have to either experience it, or have no idea what it is. That does sound like it has a sporting chance of being right, or at least it does to me.

But if so, then this does imply that there are laws and properties of reality that we do not, and perhaps can never, understand intellectually, because they are not susceptible to scientific analysis? That they work beneath, or above, the radar of our intellects, however hard we try?

If all this is true, however, then what should we do? What can we do?

What we must do, I maintain yet again, is not give in to despair simply because we don’t know the solution to the puzzle, and may never know the solution to it. Also, remember that many mysteries have resisted solution for centuries, only to finally be solved by an application of new paradigms and ways of looking at things. Above all, we must not give up, even if things appear hopeless. A hundred years from now, we may find ourselves shaking our collective heads at our current confusion. I am tempted, however, to call this question – the question of sentience – the ultimate question, to which all others are sublimated. I really do believe that if and when we solve it, there will be a collective sigh of satisfaction greater than the solution to any question that has proceeded it.

* * *

Somehow or other, whether by luck or design or an intermingling of the two, we find ourselves where and when we are. We inhabit a planet orbiting a yellow dwarf star at the edge of a rather typical spiral galaxy. The star is but one among billions in the galaxy it has found itself in, and the galaxy may be one of trillions in a universe many billions of years old and perhaps far, far older. In all that, our individual lives occupy only a few decades of time, a century if we are fortunate. There seems to be nothing particularly special about this where and when we exist, except that is one of the few places we could be in the universe, perhaps the only even, and perhaps one of the few universes we could be in. Maybe the only one. Moreover, we do not know what will happen, not merely to ourselves as individuals, but to us as a species over the next few centuries.

We have spent thousands of years beating our heads against an invincible wall, wondering what the answer to all this is, and for all our pounding still pretty much have no idea. Of course, the answer may well be that “this is all there is”, that once our bodies cease to function that is the end of both us and Us, and no beliefs, religions, philosophies, or wishful thinking can change that. Sad though that is in one respect, even if it is true I believe we should be grateful, grateful for the opportunity to have existed at all and had the opportunity to marvel at this universe we have manifested in. It is even really not so sad either, when you think about it; after all, in the billions or trillions or infinity of years before we existed we suffered not one iota for not being, so certainly after we are gone we will not suffer at all then either. It is only sad, to me at least, in that We will cease to exist with so many wonderful questions unanswered. That, I have to admit, is a bitter pill to force down.

But let us assume that this is not the case. Let us imagine that sentience, while inactive without a brain to model the universe about it, nonetheless still exists in some potential form. I use the word potential with a very specific meaning. We speak of potential energy, as when an object is raised to a certain height, or an elastic material stretched, or as a chemical potential that can lead to an energetic reaction. The energy does not exist in any active form, yet it is still there, waiting to be manifested. Quite possibly, sentience without a brain with which to experience some kind of reality, can be held in an analogous potential form. What would that mean? One possibility is the repeated incarnations of the “soul” as claimed by many Eastern religions, although I am not certain I can believe in that.

I have difficulties with this, because in Eastern religions, the soul can reincarnate as almost anything: another person, an animal, a plant, or even a rock. Yet rocks and plants, and probably even most animals, do not possess the capacity for sentience, as they lack a sufficiently complex brain and nervous system. There are other practical problems as well. Even if we reincarnate as human beings, since the number of human beings on this planet has been exponentially increasing over thousands of years, where are all the new souls to come from to inhabit all these new bodies? There is a disparity here that is hard to reconcile.

There is another tack I would like to try. I am an aficionado of the television series House, which, if you aren’t (fie on you!), is about the brilliant but renegade and rather misanthropic Dr. Gregory House and the characters and cases which spin around him in a mythical teaching hospital between Princeton and Plainsboro, NJ. One of the episodes involves Dr. House temporarily reviving a patient who has been in a coma for ten years, for the purpose of extracting family background in order to save the coma patient’s son’s life (it ends with the coma patient committing suicide in order to donate his heart to his dying son – now you know why I say fie on you if you don’t watch it). Before I begin, I have to say I find the premises of this episode highly dubious at the least: someone who has been in a coma for ten years will have undergone so much muscle atrophy and coordination loss that I doubt he could walk, let alone drive a car to Atlantic City and basically act like someone who has just woken from a short nap. But that is beside the point I want to make.

No, my question is: is the sentience that results from the coma awakening, and spends his last day in a quest for the perfect hoagie then ends by sacrificing his life for his son’s, the same sentience that ended ten years earlier? An even better question might be, does this question even make any sense? The re-awakened father would of course insist that he his in every way conceivable the same person, but how much does that utterly sincere insistence count for? And what possible tests and / or measurements could we make to settle the issue?

I have to confess to something. This is not a mere academic issue to me. I was once in a coma, from which I fortunately awoke after several days. But does that make any difference? Like that father in House, I absolutely insist that I am the same Me that fell into that coma, but how can I, or anyone, really know? And again I ask, does the question even make sense?

Maybe it is an absurd question. Or, not so much absurd as worded incorrectly. Perhaps what seems to happen to Us in those moments, or days, or years, when we still exist but We do not is that time ceases to exist for Us. Just like, according to Einstein’s Special and General Theories of Relativity, time ceases to exist under certain conditions – if we were to ride on a beam of light or (if I understand what I have read correctly) fall into an infinitely deep gravity well – time comes to a complete stop for Us whenever the conditions needed to manifest Us ceases to exist. The question then is, do those conditions exist only within our own brains, for if so, then our current lives are the only ones We can ever manifest in?

* * *

I suspect that I have frustrated and dissatisfied you, dear reader, for I keep promising answers to this deepest of questions, but invariably find myself only circling about and finding myself at my own beginnings, my own head-shaking ignorance and failure of my own imagination and curiosity to solve this most impenetrable of puzzles

Will I give up then? No, first of all because I see no way of letting go of my curiosity and wonder and imagination, without letting go of what it means to be a living, sentient mind in a universe we still have so much to explore within. If there are places and times I have no concept of how to reach, then I am simply going to accept them for the time being, and hope that at some point in the future my eyes will start to open about them. Nor will I relinquish the scientific approach to thinking about reality, for it has served us so well, and has provided answers to what appeared to be impenetrable mysteries, and so I cannot give up hope on it, certainly not at this time and place in humanity’s evolution. Perhaps, of course, these things will lead to my death with so many important questions unanswered, and, yes, as I have admitted, that disturbs me. But, as I said, to stop now and lay down all of the weapons and tools of the mind and surrender to ignorance; that is something I cannot even conceive of doing. I would certainly die of despair if I even so much as tried.

So we have come around and around, and it the end must still admit that this greatest of mysteries has not yielded to science, at least not yet. And yet, that is all right. Mysteries are the lifeblood of science, and indeed of all our wonderings and imaginative escapades. Maybe, like the character in the Monty Python sketch I mentioned early in this book, we even need them, need these challenges to our curiosity, as though they are part of what gives our lives meaning. I know that they have given my life at least a healthy part of its meaning.

* * *

"There is a theory which states that if ever anybody discovers exactly what the Universe is for and why it is here, it will instantly disappear and be replaced by something even more bizarre and inexplicable. There is another theory which states that this has already happened."

Douglas Adams, The Hitchhiker's Guide to the Galaxy (1979)

"Now my own suspicion is that the universe is not only queerer than we suppose, but queerer than we can suppose."

JBS Haldane, Possible Worlds and Other Papers (1927), p. 286

As I said at the beginning, a large part of this book is about what it means to be human, with curiosity, wonder, and imagination being fundamental parts of the answer. I also stressed the special importance of imagination, supplemented by technology, along with the warning that if we really wish to understand the universe we live in, we must not limit ourselves to our sensory experiences and our intuitions about them. We saw how important that became once we started deviating from the norms of our existence, whether in space or time. When we are dwelling in the world of the ultra-small or large, slow or fast, the laws of physics deviate from common sense in ways we would never have predicted. Phenomena such as the uncertainty principle and the depths of geologic time, time dilation and the bending of spacetime become increasingly important as we move further and further away from the norms of our everyday existence. We found that if we allowed those deviations to take us logically wherever they went then, however strange our discoveries, they could be integrated into the whole of understanding.

We also came to understand that the paths we took were our personal ones, each unique to us even if, ultimately, we all found ourselves in the same place in the end, that end being still finding ourselves facing the same ages old mysteries of our own existence. This is one of the crucial paradoxes of the human condition, I believe; that we all experience our lives as infinitely separated individuals, while underneath we are all tied together by the same laws, the same processes, the same foundations. It is as though each of us perceives ourselves as alone in a tiny boat on the open ocean, winds whipping and waves constantly washing water into the boat, forcing us to bale with all our strength and persistence just to stay afloat, while in fact, ironically, we are all collectively in one huge boat, with each of us making our tiny contribution to keeping the boat afloat and headed for – what land we are uncertain, but whatever it is we shall all arrive there together, in the end.

In the end, maybe this is our place in the scheme(s) of things. I am not the first person to speculate that we may be nothing more than reality’s attempt to comprehend itself. If so however, then we are faced with another mystery, that of how reality can have intentions or goals at all instead of being nothing more than the blind working out of physical laws. A mystery which only becomes deeper if we assume that intelligence, in some form, is itself part of that reality.

I stated at the outset of this book that I do not intend to give in to nihilism or despair, and I will take the time to reaffirm this promise again. Somehow we reasoning, questioning, imagining animals have found ourselves in this universe, and that alone should provoke our minds to keep trying to discover how and why. Indeed it is my view that we are probably still closer to the beginning of our quest than the end. I will also take the time to state my personal gratitude that we are in the middle of it.

We are born as, and grow up into, creatures of curiosity, wonderment, imagination, and rational thought. I do not care what nation or culture you were raised into, what you were taught, or what experiences you have had. Merely by being human, you still have all these traits within you, each one waiting to boil up to the surface at any time. I know that I have been astonishingly fortunate in this respect, in one sense more than most in this world, but at the same time I can’t believe that I have been any more gifted in these things than anyone else. I have just had the good fortune to have these things nurtured and encouraged.

I remember being a child with all these things within me, and nothing gives me more pleasure than today, at fifty-three years of age, to discover that same child just as strong. Though I have spent a half-century’s worth of growing, experiencing, maturing; though I have married, raised children, and known “The heart-ache, and the thousand natural shocks that flesh is heir to” including pain I thought I would never recover from or survive; though I have stared into space and wondered what the point of those pains were … that part of me has never been diminished or defeated in any way.

And so there is nothing more for me to do except present myself as an inspiration, and as a hope. If you have any doubts, then go somewhere where the lights and pollution of the city cannot find you. Wait until the sun goes down, and then lie on the grass, staring skywards at the stars. Stare, and remember that for each one you see, there are trillions beyond your sight, beyond the sight of the most powerful telescopes for that matter. Gaze at the fierce beacons pouring their fires down upon you, and wonder. Though this universe we live in is far vaster than our imaginations can even begin to encompass, I believe you will know what I mean. Though we are but the most mortal of beings, barely eking a century’s worth of experience of the billions of years those beacons have shown, each of us has still our own meaning, our own purpose, whether we know it or not. I believe this will dispel all those doubts.

Does Depression Change the Way People Perceive the World?



Depression is a state of low mood and aversion to activity that can affect a person's thoughts, behavior, feelings and sense of well-being.^[1] Depressed people feel sad, anxious, empty, hopeless, worried, helpless, worthless, guilty, irritable, hurt, or restless. They may lose interest in activities that once were pleasurable, experience loss of appetite or overeating, have problems concentrating, remembering details, or making decisions, and may contemplate, attempt, or commit suicide. Insomnia, excessive sleeping, fatigue, loss of energy, or aches, pains, or digestive problems that are resistant to treatment may also be present.^[2]
Depressed mood is not always a psychiatric disorder. It may also be a normal reaction to certain life events, a symptom of some medical conditions, or a side effect of some drugs or medical treatments. Depressed mood is also a primary or associated feature of certain psychiatric syndromes such as clinical depression. (wiki)

People with depression often say that they experience the world differently from others. They commonly report changes in appetite, and sometimes say that “time seems to drag on.” And the English language contains many metaphors that link depression with color—we often say, for example, that someone with depression is “feeling blue.” A series of recent studies now offers preliminary evidence that depression may, indeed, alter aspects of perception.

In the most recent, mathematical psychologist Diana Kornbrot of the University of Hertfordshire and her colleagues recruited 46 students and used the Beck Depression Inventory (BDI) to gauge their mood. The BDI consists of 21 multiple-choice questions, and is widely used by psychiatrists to assess the severity of depression.

Kornbrot and her colleagues split the study participants into two groups, one with high BDI scores, corresponding to dysphoria, or mild depression, the other with low scores. They then asked the participants to listen to a series of sounds that varied from 3 seconds to 65 seconds in length, and to estimate how long they were as accurately as possible. Participants also were asked to produce sounds of varying lengths using a computer keyboard.

The researchers found a correlation between participants’ BDI scores and the accuracy with which they could estimate the length of the sounds they heard and produced: Those with higher scores made more accurate estimates than those with lower scores.

“What we see is that those with mild depression seem to be better at paying attention to short periods of time,” says psychologist Rachel Msetfi of the University of Limerick, a co-author of the study. The finding suggests that people with depression experience a time dilation effect, and lends support to the controversial notion of depressive realism, which posits that people who are depressed have a more accurate perception of reality than others.

Msetfi thinks that this time dilation might be related to one of the symptoms of severe depression. People with severe depression often experience helplessness, or the feeling that they are not in control of their lives, and this is usually accompanied by a feeling of guilt.

Time perception is crucial for agency, the sense that we are in control of our actions. Normally, our actions are followed very closely in time by their consequences; this can give us the sense that the two are causally related, and that we are responsible for the consequences of our actions.

 Other work suggests that the brain actively compresses time to make action and cause seem closer together in time. This process, referred to as intentional binding, enhances our sense of agency. When the interval between an action and its effects is deliberately extended, people feel less in control of their actions. There is evidence that this process is perturbed in people with schizophrenia, and this may contribute to their propensity to misattribute their thoughts or actions to external forces.

“Subtle changes in the way we process time may contribute to the sense of helplessness [in people with depression],” says Msetfi. “If you have disturbances in the way you process time and context and the relationship between them, then you’re going to have some disturbance in your experience of everyday life and reality.”

Msetfi suggests that perturbations of what she calls the ‘psychological time-space continuum’ might be a general deficit that underpins other psychopathological conditions. “I don’t have any solid evidence to support that yet, though,” she says.

Another recent study, led by Petra Platte of the University of Würzburg, suggests that depression alters peoples’ perception of taste, too. Platte and her colleagues used film clips to induce sad, happy or neutral moods in 70 otherwise healthy participants. They used the BDI to assess the participants’ mood, and asked them to rate the intensity of sweet, sour, bitter, fatty, and umami stimuli, all of which were given at several different concentrations.

They found that mood modulated the participants’ perception of the stimuli—those with higher BDI scores could not differentiate between low and high fat concentrations after the induction of both negative and positive moods. The researchers suggest that this apparent deficit in taste perception might foster unhealthy eating habits in people with mild, subclinical depression.

It follows that we would expect to see a higher incidence of obesity in people who are depressed. Obesity and depression are indeed correlated, but the relationship between them is a complex and reciprocal one. It is by no means clear whether altered taste perception is what causes obesity in patients with depression.

In 2010, another group of German researchers reported that people with major depressive disorder (MDD) have reduced sensitivity to visual contrast compared with healthy controls. Emanuel Bubl of the University of Freiburg and colleagues recruited 40 patients diagnosed with MDD and 40 healthy controls matched for age and sex. They showed all the participants black and white checkerboard patterns, and used pattern electroretinography to measure the responses of their eyes. This technique uses electrodes placed on the cornea to measure the electrical activity of cells in the retina, with the size of the response indicating the extent of contrast gain.

Patients with MDD responded differently than the controls; they had markedly reduced contrast gain-related activity, suggesting that they were less sensitive to contrast. Within the group of MDD participants, the size of the responses was closely correlated with the severity of depression. The more severe the depression, the greater the reduction in contrast gain, and those who were taking anti-depressants also displayed slightly larger responses than those who were not.

Buble and his colleagues found that they could predict which of the participants had been diagnosed with MDD from the pattern electroretinography recordings alone, with an accuracy of greater than 90 percent. But they could not determine whether the effect they observed was specific to depression.  

Several other studies published in recent years suggest that sensitivity to pain is similarly reduced in depression. Taken together, these findings suggest that depression alters basic perceptual processes across multiple sensory modalities.

Big caveats

But cognitive neuropsychologist Keith Laws of the University of Hertfordshire, who was not involved in any of the studies, has reservations about the findings. “In two of the studies, they’re looking at people who score within the normal range of the BDI,” he says. “These are completely healthy people, so it’s difficult to know what they mean in the context of people with depression.”

Moreover, the results are based largely on participants’ self-reports of the mood they were in at the time. Such reports are highly subjective in nature, and not necessarily accurate. And the studies divided participants into two groups according to their BDI scores, and then compared the averaged results of the groups, rather than those of individual participants. Consequently, the results from both groups overlapped significantly, making it difficult to draw any firm conclusions from them.

“It’s very interesting work, but I’m not altogether convinced by it,” says Laws, “and I think all of these studies need to be replicated and extended in order to determine whether depression actually does alter perception.”

 - By Moheb Costandi, from BrainFacts.org (

Hawking & Mlodinow: No 'theory of everything'

Hawking & Mlodinow: No 'theory of everything'

In a Scientific American essay based on their new book A Grand Design, Stephen Hawking and Leonard Mlodinow are now claiming physicists may never find a theory of everything. Instead, they propose a "family of interconnected theories" might emerge, with each describing a certain reality under specific conditions.

Most of the history of physics has been dominated by a realist approach. Scientists simply accepted that their observations could give direct information about an objective reality. In classical physics, such a view was easily defensible, but the emergence of quantum mechanics has shaken even the staunchest realist.

In a quantum world, particles don't have definite locations or even definite velocities until they've been observed. This is a far cry from Newton's world, and Hawking/Mlodinow argue that - in light of quantum mechanics - it doesn't matter what is actually real and what isn't, all that matters is what we experience as reality.

As an example, they talk about Neo from The Matrix. Even though Neo's world was virtual, as long as he didn't know it there was no reason for him to challenge the physical laws of that world. Similarly, they use the example of a goldfish in a curved bowl. The fish would experience a curvature of light as its reality and while it wouldn't be accurate to someone outside the bowl, to the fish it would be.

Scientific American: The Elusive Theory of Everything (paywalled)

"In our view, there is no picture or theory-independent concept of reality. Instead we adopt a view that we call model - dependent realism: the idea that a physical theory or world is a model (generally of a mathematical nature) and a set of rules that connect the elements of the model to observations. According to model - dependent realism, it is pointless to ask whether a model is real, only whether it agrees with observation. If two models agree with observation, neither model can be considered more real than the other. A person can use whichever model is more convenient in the situation under consideration."

This view is a staunch reversal for Hawking, who 30 years ago argued that not only would physicists find a theory of everything, but that it would happen by the year 2000. In his first speech as Lucasian Chair at Cambridge titled "Is the end in sight for theoretical physics?," Hawking argued that the unification of quantum mechanics and general relativity into one theory was inevitable and that the coming age of computers would render physicists obsolete, if not physics itself.

Of course, Hawking has become rather well known for jumping way out on a limb with his public remarks and for decades he embraced supergravity as having the potential to solve theoretical physicist's ills, even hosting a major conference on it in 1982. However, but Hawking has never harbored allegiances to theories that describe a physical reality.

So, while two well-known physicists coming out against a theory of everything is compelling, it really shouldn't seem like anything new for Hawking.

"I take the positivist view point that a physical theory is just a mathematical model and that it is meaningless to ask whether it corresponds to reality. All that one can ask is that its predictions should be in agreement with observation."

Stephen hawking, The Nature of Space and Time (1996)

An Open Letter to "Duck Dynasty" and Supporters

Posted: 12/23/2013 8:43 am                                                                                                     

  

Dear Duck Dynasty and Supporters (Sarah Palin, Bobby Jindal, etc.),

Last week two members of the all-woman band "Pussy Riot" were being freed from prison after serving over a year because they had the audacity to peacefully protest the Russian government and its oppressive policies.

That would never happen in this country. What we call--and you yell--"Freedom of Speech" is meant to protect the right of any citizen to say whatever they wish (within reason of public safety) without repercussions from the government.

Though it's certainly a heated debate, the spirit of freedom of speech is in protecting the opinion of the minority on an issue--whether that be a minority of background or population or power. It's meant to give everyone the chance to voice their opinion.

And although your opinion on homosexuality is now in the minority in this country, your privilege as straight folks to say things that perpetuate dangerous myths and hatred has helped keep in place laws that treat those in the LGBT community as second class citizens.

The First Amendment ONLY guarantees the government can't oppress you for your opinions, it does not dictate to private entities what they can and cannot do in regards to the words that come out of your mouth.

So, when you say stupid shit like "I never, with my eyes, saw the mistreatment of any black person. Not once." or "whether they're homosexuals, drunks, terrorists. We let God sort 'em out later, you see what I'm saying?" or literally compare non-Christians to Nazis, a private company like A&E has every right to can your ass, regardless of who does and does not agree with them.

Further, I've noticed a strange absence of that much-heralded "let the free market do its job" commentary that was so prevalent when folks were boycotting Chick-fil-A for their anti-gay bigotry. Now, that A&E has literally made a decision in response to the market, you're crying foul. What happened to capitalism being a driving force for social equality?

You absolutely have freedom of speech, but you do not have the right to a guaranteed audience or freedom from criticism or freedom from private sector consequences.

So, please take your duck whistles and complaints to the nearest Chick-fil-A and let the rest of us celebrate the triumph of the human spirit and actual bravery in free speech with those folks from Pussy Riot.

 

          Follow Charles Clymer on Twitter: www.twitter.com/cmclymer

 

 

Indonesia cave reveals history of ancient tsunamis

Read more at http://www.philly.com/philly/news/nation_world/20131224_ap_13f270d59776449c9fd9890c6dccf395.html#idC1bUcJWibKebEQ.99

 

In this Monday, Dec. 2, 2013 photo, a guide uses candles to illuminate the interior of a cave which scientists said reveals a history of ancient tsunamis in Lhong, Aceh province, Indonesia. The cave discovered near the source of 2004's massive earthquake-spawned tsunami in Indonesia contains the footprints of past gigantic waves dating up to 7,500 years ago, a rare natural record suggesting future generations living in the coastal area must stay prepared because disasters can occur in relatively short bursts or after long lulls. (AP Photo/Heri Juanda)

             

MARGIE MASON, The Associated Press

Posted: Tuesday, December 24, 2013, 1:44 AM

             

JAKARTA, Indonesia (AP) - A cave discovered near the source of Indonesia's massive earthquake-spawned tsunami contains the footprints of past gigantic waves dating up to 7,500 years ago, a rare natural record that suggests the next disaster could be centuries away - or perhaps only decades.

The findings provide the longest and most detailed timeline for tsunamis that have occurred off the far western tip of Sumatra island in Aceh province. That's where 100-foot (30-meter) waves triggered by a magnitude-9.1 earthquake on Dec. 26, 2004, killed 230,000 people in several countries, more than half of them in Indonesia.

The limestone cave, located within a couple hundred yards (meters) of the coast near Banda Aceh, is about 3 feet (1 meter) above knee-high tide and protected from storms and wind. Only huge waves that inundate the coastal area are able to gush inside.

Researchers in 2011 uncovered seabed sand deposits that were swept into the cave over thousands of years and neatly layered between bat droppings like a geological cake. Radiocarbon analysis of materials, including clamshells and the remains of microscopic organisms, provided evidence of 11 tsunamis before 2004.

The disasters were by no means evenly spaced, said lead researcher Charles Rubin from the Earth Observatory of Singapore. The last one occurred about 2,800 years ago, but there were four others in the preceding 500 years.

And it's possible there were others. Researchers know, for instance, that there were two mammoth earthquakes in the region around 1393 and 1450. Rubin said a big tsunami could have carried away evidence of other events through erosion.

The scientists are still working to determine the size of the waves that entered the cave.

"The take-home message is perhaps that the 2004 event doesn't mean it won't happen for another 500 years," said Rubin, who added that the cave was discovered by chance and not part of planned field work. "We did see them clustered together closer in time. I wouldn't put out a warning that we're going to have an earthquake, but it shows that the timing is really variable."

The quake that triggered the 2004 tsunami surprised scientists because the fault that unleashed the megathrust temblor had been quiet for hundreds of years. And since the last big earthquake had struck more than 500 years earlier, there was no surviving oral history that could have helped people understand the risk.

Since 2004, much research has been done to try to learn about the area's past by examining sand deposits, uplifted coral and GPS data.

"The findings are very significant," Katrin Monecke, a geosciences professor at Wellesley College in Massachusetts wrote in an email. She worked on tsunami sand deposits discovered in marshes in the area, but was not involved with the cave research, which was presented this month at an American

Geophysical Union conference in San Francisco. "The sand sheets in the cave cover a very long time span and give an excellent idea about earthquake frequency."

Despite the long record preserved in the cave, Rubin said it did not provide any clear clues about tsunami frequency or when events might happen in a relatively close period of time.

Geologist Kerry Sieh, director of the Singapore group and also part of the cave investigation, has predicted that another monster quake could rock the area in the next few decades. They tend to come in cycles and the 2004 temblor heaped more pressure on the fault. However, the history is so variable, it's impossible to make an exact forecast.

"By learning about the type of tsunamis that happened in the past, maybe we can do planning for mitigation for the next tsunami," said Nazli Ismail, head of the physics and geophysics department at Syiah Kuala University in Banda Aceh who worked on the project.

Indonesia is an archipelago located on the so-called "Ring of Fire," a horseshoe of fault lines and volcanoes surrounding the Pacific Basin. It is home to some of the world's biggest and deadliest seismic activity.