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Wednesday, January 8, 2014

Evolution of Confusion -- Daniell Dennet

http://www.youtube.com/watch?v=5Bwe7TIv4LY&feature=player_detailpage


















Daniel Dennet on The Evolution of Confusion


Could Other Animals Have (their version of) Gods Too? Hitch Got Me Thinking

 
 
 
 
 
 
 
 
 
 
 
 
 
At first sight this seems the usual delightfully charming Hitchens saying the kind of things he was and is so famous and fondly remembered for.  Only on second or third sight did I realize that, at least this time, the great man was in error.  Completely in error.
 
For one thing, it is an unforgiveable insult to chimpanzees all over the world; worse, to the entire -- sans H. sapiens -- animal kingdom on this planet.  If creating gods really is maladaptive, irrational, and just plain foolish, then we humans must be at the bottom of the evolutionary cesspool, hardly near the top.  Yet Hitchens unfortunately implies exactly the opposite, as though creating supernatural beings somehow "reduces" our evolutionary pedestal down to the level of our clownish closest cousin.  By half a chromosome, but that's a lot.
 
But then I re-wondered about it.  How do we know that chimps haven't made, somewhere in their history, things akin to our gods?  They certainly aren't capable of science, nowhere near to our level at least; so why shouldn't they believe in the supernatural?  Lack of science is certainly most the reason almost all of our ancestors believed in gods and other supernatural phenomenon.
 
On the other hand, are chimps capable of belief, which involves some pretty sophisticated cognition skills?  I don't know if (or how) there have been studies of this, or even conclusions drawn, but I will say this:  don't bet your life's fortune that the answer is negative.  So many animals, including the other apes, have been shown over the last 20-40 years to possess much more sophisticated behaviors and cognition skills than we'd ever suspected.  New discoveries seem to happen almost daily.  (Hence the animal rights movement.)
 
"Half a chromosome away from being chimpanzee" is probably at least a bad analogy; that little bit of DNA might not make as much difference as we suppose.  It is certainly nothing to be either proud or ashamed of, and quite possibly has nothing to do with believing in gods or not.
 
Still -- it sounds so Hitch.  So on the money.


Dark matter 'wind' may be warped by the sun

18:00 08 January 2014 by Katia Moskvitch
Source:  http://www.newscientist.com/article/dn24830-dark-matter-wind-may-be-warped-by-the-sun.html#.Us2x850o6L9

 














Dark-matter hunters may need to check their calendars. The sun's gravity could change the time when dark matter signals are detected on Earth, which could help sharpen the search for the elusive substance.
 
Invisible dark matter is thought to make up most of the matter in the universe. Physicists hope to detect it in the form of weakly interacting massive particles (WIMPs) when they collide with ordinary matter in underground detectors.
 
Some have argued that the rate of such interactions should vary with the seasons, as Earth's orbit brings it ploughing through the cloud of dark matter suffusing the galaxy. When the planet heads into this "WIMP wind", around 1 June, we should see more dark matter strikes; in December, when Earth is moving downwind, we should see fewer.
 
Previously, two experiments, including the DAMA detector at Gran Sasso, Italy, and the CoGeNT detector in Soudan, Minnesota, reported observing just this sort of seasonal signal. But these claims have attracted scepticism because more-sensitive detectors have come up empty.

Warp factor

Now, Benjamin Safdi of Princeton University and his colleagues note something that all experiments have neglected: the sun. As WIMPs stream through the solar system, the sun's gravity bends their trajectories, focusing the streaming particles on a particular location in Earth's orbit. This effect can shift the date of the maximum number of collisions by anything from a few days up to several months, depending on the WIMPs' mass and speed. "This force warps the dark matter 'wind' in a way that had not previously been noticed," Safdi says.


The fact that the date of maximum WIMP collisions should change depending on their energy could lend future searches a sharper scalpel to scrape true dark matter signals away from background noise, he adds.
 
"Our result gives dark matter direct-detection experiments an excellent way of distinguishing real interactions with the galactic dark matter halo from background," Safdi says. "It is hard to imagine a background source which could mimic this energy-dependent modulation."

Punchline coming

The work does not explain DAMA's possible dark-matter signal, but re-analysing the data using the new approach could help support or refute their results, Safdi says.
 
"There is already a slight trend in the data consistent with our prediction for the gravitational focusing effect – that is, the date of the maximum moves further away from June 1 at lower energies," says team member Samuel Lee, also of Princeton. "One punchline of our study is that accounting for the gravitational focusing effect can perhaps rule out or confirm the dark-matter interpretation of the DAMA annual modulation."
 
Richard Gaitskell of Brown University in Providence, Rhode Island, who works on a direct-detection experiment in South Dakota called LUX, says that the new work could be important for helping design future experimental set-ups. "These researchers have clearly demonstrated just how potentially interesting data from a direct-detection experiment can be," he says.
 
Journal reference: Physical Review Letters, DOI:10.1103/PhysRevLett.112.011301


 

Hawking & Mlodinow: No 'theory of everything'

Thursday, September 30, 2010
 














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
"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)

Organic mega flow battery promises breakthrough for renewable energy

59 minutes ago in Phys.org 

Organic mega flow battery promises breakthrough for renewable energy       
Large-scale storage of renewable energy for use when the sun isn't shining and the wind isn't blowing. Energy from solar panels is shown stored in green and blue chemicals in Harvard flow battery storage tanks, powering this green city at …

A team of Harvard scientists and engineers has demonstrated a new type of battery that could fundamentally transform the way electricity is stored on the grid, making power from renewable energy sources such as wind and solar far more economical and reliable.
The novel battery technology is reported in a paper published in Nature on January 9. Under the OPEN 2012 program, the Harvard team received funding from the U.S. Department of Energy's Advanced Research Projects Agency–Energy (ARPA-E) to develop the innovative grid-scale battery and plans to work with ARPA-E to catalyze further technological and market breakthroughs over the next several years.

The paper reports a metal-free that relies on the electrochemistry of naturally abundant, inexpensive, small organic (carbon-based) molecules called quinones, which are similar to molecules that store energy in plants and animals.

The mismatch between the availability of intermittent wind or sunshine and the variability of demand is the biggest obstacle to getting a large fraction of our electricity from renewable sources. A cost-effective means of storing large amounts of electrical energy could solve this problem.

The battery was designed, built, and tested in the laboratory of Michael J. Aziz, Gene and Tracy Sykes Professor of Materials and Energy Technologies at the Harvard School of Engineering and Applied Sciences (SEAS). Roy G. Gordon, Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science, led the work on the synthesis and chemical screening of molecules. Alán Aspuru-Guzik, Professor of Chemistry and Chemical Biology, used his pioneering high-throughput molecular screening methods to calculate the properties of more than 10,000 quinone molecules in search of the best candidates for the battery.

Flow batteries store energy in chemical fluids contained in external tanks—as with fuel cells—instead of within the battery container itself. The two main components—the electrochemical conversion hardware through which the fluids are flowed (which sets the peak power capacity), and the chemical storage tanks (which set the energy capacity)—may be independently sized. Thus the amount of energy that can be stored is limited only by the size of the tanks. The design permits larger amounts of energy to be stored at lower cost than with traditional batteries.


Read more at: http://phys.org/news/2014-01-mega-battery-breakthrough-renewable-energy.html#jCp
 


‘Habitable zones’ around stars ten times wider than we thought – study

Published time: January 08, 2014 14:31 by RT
 

A new paper published in the journal, Planetary and Space Science, describes how living organisms have just as much chance of surviving in areas below their uninhabitable planets’ surfaces.
This includes planets a staggering distance away from their stars, as well as even those that were recently discovered to be drifting in space by themselves, with no apparent host star. It is all about temperature.

The previous commonly accepted assertion was that the ‘Goldilocks’ zone was a requirement. It is the zone both far away and near to its star to provide the kind of climate capable of sustaining life, because it supports water which is neither boiling hot nor frozen.

Now a team of researchers from Aberdeen and St. Andrews universities has an updated view of things. PhD student Sean McMahon, author of the paper, says “that theory fails to take into account life that can exist beneath a planet's surface. As you get deeper …the temperature increases, and once you get down to a temperature where liquid water can exist – life can exist there too.”

To prove this, the scientists devised a computer model to cleverly approximate temperatures below the surfaces of planets by inputting the distance to their respective stars and crossing that with the planet’s size.

Using that model they discovered that the radius around a star, capable of supporting life, increased three-fold if new data on depth at which life can exist below the surface of a given planet were taken into account.

"The deepest known life on Earth is 5.3 km below the surface, but there may well be life even 10 km deep in places on Earth that haven't yet been drilled,” McMahon said.
What adds to the excitement is that the model allows for potentially expanding the habitable zone even more. If indeed we do find life 10km below the Earth’s surface, the math tells us that Earth-like planets could support life as far as 14 times the distance previously considered to be the Goldilocks zone.
To put this into perspective – our current habitable zone is considered to reach out as far as Mars. But new measurements that account for life existing under rocky surfaces take that radius as far as Jupiter and Saturn.

For example, the recently discovered Gliese 581 d could be a candidate. Sure, it is about 20 trillion kilometers away, but its cold surface could well hide life a couple of kilometers below the surface, scientists assume.

Scientists are excited at the subsurface theory on sustaining life. We can now widen our search for life, they hope, adding that the new findings are so radical that the fact of life on Earth (which itself is very different from the thousands of planets we know about) could itself be anomalous because life receives much more protection inside a warm, mineral-rich rock than risking survival on its inhospitable surface.

Tuesday, January 7, 2014

The Way Skeptical Thinking Works

















Many many years ago, I had a very good friend, someone I cared for deeply.  She was intelligent, funny, very kind and helpful, almost always (it seemed) in a good mood.  She did have one "flaw" however, although I use that word with compassion because it was the kind of flaw that is (alas) probably just part of human nature.  The flaw was a serious lack of skeptical thinking.  Why, I'm not certain.  She was easily intelligent enough to have it.  Perhaps it was her years as a member of the one true religion and acquisition of some position and responsibility in it that defeated her skepticism and left her a believer.  (To be fair, I was in this religion for a number of years too, but it didn't defeat my natural skepticism and I escaped in time.)

So much for overtures, because I want to discuss a specific event between her and me.  One fine day (all days in San Diego are fine days, until you get sick of it) she told me about her "theory" that the ancient Egyptians (and perhaps Mesopotamians) must have visited the Mayan and/or other Central American cultures.  Reasoning?  Both "ancient" cultures built large pyramids constructed of stone.  That was it; she offered no other reasoning, no other evidence or logic, in the "theory's" support.  She was probably as certain of it as she was of her religious truths.

If your mind is anything like mine's, and assuming you've heard this idea before, alarm bells were starting to clang in your head before you read this far.  If you have a reasonable knowledge of history and geography (shame on you if you don't!) you can just sense that there is something(s) seriously wrong here, that the pieces of this puzzle surely can't hang together.  To revive an old saying,  "You can feel it in your bones."

That was precisely my experience, and I believe it is essential for our skeptical abilities to mature.  Note that its main nutrient is knowledge, and not even very in-depth knowledge.  When anyone tells us something that feels (to confirm, yes, I believe this usually starts as an act intuition) out of synch with our own ideas and knowledge, it can make us startle as though we'd been teleported to a different world or time.  Of course, if your ideas and knowledge are incorrect, skepticism is pretty much in vain.

That's where it starts, I suggest, with that (often small) sense of dislocation, because it conflicts with at least something we know to be true.  But if you end there, you would rightfully accused of just dismissing the person without argument.  Furthermore, it would probably leave you with a funny feeling, as if you've failed yourself somehow.  And you would be right here too.  (Of course you can just make an agreeable grunt and change subject:  as I think Shaw said,  "Arguments are to be avoided.  They are always vulgar and often persuasive.)

Furthermore, there is always a real possibility of you being wrong, or not having enough facts at hand.  Or you can't summon all your defenses for the barrage of logical fallacies and cognitive biases about to assault you.

So I decided to file the issue away, to ruminate about it later when I was alone and could think clearly.  When I did, the objections to her "theory" came swiftly and completely enough.  I am not going to go over them (I am confident that you can find them yourselves quickly too).

So what happened to us, her historical speculations, and so forth?  Between us nothing, for I knew better than to debate a firm believer in the one true religion -- I did say I cared very much for her, didn't I?  Let sleeping cats sleep.  But for me, it was an important triumph of my mind, a victory I have always carried with me, knowing I may need it any time.  And don't doubt one thing:  life has that much richer for it.

Bayesian inference

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Bayesian_inference Bayesian inference ( / ...