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Friday, January 31, 2014

Who's the most significant historical figure?

From Leonardo da Vinci to Einstein, and Shakespeare to Stephen King, two data analysts have ranked the most significant people in history – do the results seem right?
Portrait of man in black with shoulder-length, wavy brown hair, a large sharp nose, and a distracted gaze 
 
Steven Skiena and Charles B Ward
The Guardian,                 
 
Shakespeare, Austen, Homer, King, Dickinson and Shelley
The Literary Top 50 … top row from left: Shakespeare, Austen and Homer;
bottom row: King, Dickinson and Shelley
 
People love lists, and are perhaps even more fascinated by rankings – lists organised according to some measure of value or merit. Who were the most important women in history? The best writers or most influential artists? Our least illustrious political leaders? Who's bigger: Hitler or Napoleon? Picasso or Michelangelo? Charles Dickens or Jane Austen? John, Paul, George or Ringo?

We work in the fields of data and computer science and do not answer these questions as historians might, through a principled assessment of a person's achievements. Instead, we aggregate millions of opinions. We rank historical figures just as Google ranks web pages, by integrating a diverse set of measurements of reputation into a single consensus value.

Significance is related to fame but measures something different. According to our system, forgotten US President Chester A Arthur (who we rank at 499) is more historically significant than pop star Justin Bieber (ranked 8,633), even though Arthur may have a less devoted following and certainly has lower contemporary name recognition. We believe our computational, data-centric analysis provides new ways to understand and interpret the past.

Historically significant figures leave statistical evidence of their presence behind, if one knows where to look for it. We use several data sources to fuel our ranking algorithms. Most important is Wikipedia, the web-based, collaborative, multi-lingual encyclopedia. Wikipedia is enormous, featuring well over 3m articles in its English edition alone. But we use it in a manner quite different from the typical reader, by analysing the Wiki pages of more than 800,000 people to measure quantities that should correspond to historical significance. We would expect that more significant people should have longer Wikipedia pages than those less notable because they have greater accomplishments to report. The Wiki pages of people of higher significance should attract greater readership than those of lower significance. The elite should have pages linked to by other highly significant figures, meaning they should have a high PageRank, the measure of importance used by Google to identify important web pages. We combine these other variables into a single number using a statistical method called factor analysis. But we need one final correction: to fairly compare contemporary figures such as Britney Spears against, say, Aristotle, we must adjust for the fact that today's stars will fade from living memory over the next several generations. By analysing traces left in millions of scanned books, we hope to measure just how fast this decay occurs, and correct for it.

We have naturally received strong reactions from readers of our book Who's Bigger? complaining about our computational methodology. Certain historians have complained that Wiki cannot be trusted as a source for anything. This is pretty silly. People find Wikipedia articles to be generally accurate and informative, or else they wouldn't read them. Where do you head to read up on a new topic you are interested in? We think it is clear that anyone (or anything, like our algorithms) that has read all of Wikipedia would be in an excellent position to discourse about the most important people in recorded history.

More cogent is the complaint that our results are culturally biased because we analyse only the English edition of Wikipedia. How can we fairly assess the significance of Chinese poets against US presidents? We agree that any ranking of historical significance is indeed culturally dependent and so, yes, our rankings have an Anglocentric bias. But the depth of Wikipedia is so great that there are hundreds of articles about Chinese poets in the English edition.

Others highlight a few contemporary figures that they deem us to have overrated, such as Britney Spears (689) or Barack Obama (111), and use this anecdotal evidence to sneer. But we also conduct validation procedures, and compare our rankings to public opinion polls, Hall of Fame voting records, sports statistics, and even the prices of paintings and autographs.

Anecdotal evidence is not as compelling as it might seem. British readers have complained that our algorithms don't rank British figures high enough just as strongly as Spanish readers think we are unfair to their compatriots. But our book is designed in part to generate debate.

Our overall top 30

Portrait of Elizabeth I of England At No 13 … Elizabeth I. Photograph: Getty Images
1 Jesus
2 Napoleon
3 Muhammad
4 William Shakespeare
5 Abraham Lincoln
6 George Washington
7 Adolf Hitler
8 Aristotle
9 Alexander the Great
10 Thomas Jefferson
11 Henry VIII
12 Charles Darwin
13 Elizabeth I
14 Karl Marx
15 Julius Caesar
16 Queen Victoria
17 Martin Luther
18 Joseph Stalin
19 Albert Einstein
20 Christopher Columbus
21 Isaac Newton
22 Charlemagne
23 Theodore Roosevelt
24 Wolfgang Amadeus Mozart
25 Plato
26 Louis XIV
27 Ludwig van Beethoven
28 Ulysses S Grant
29 Leonardo da Vinci
30 Augustus

Top pre-20th-century artists

Self-Portrait by Leonardo da Vinci                       
At No 1 … Leonardo da Vinci Photograph: Bettmann/CORBIS

Art has been a uniquely human activity for more than 40,000 years. But the names of artists went unrecorded for most of this period. The identities of several prominent Greek artists, most notably Phidias, survive through contemporary written accounts and Roman copies of their work. But the notion of artists with distinct identities then faded, not to be revived until the late middle ages. The great painters of the Renaissance dominate our rankings of the most significant pre-20th century artists.

1 Leonardo da Vinci (overall ranking 29)
2 Michelangelo (86)
3 Raphael (140)
4 Rembrandt (189)
5 Titian (319)
6 Francisco Goya (366)
7 El Greco (465)
8 Albrecht Dürer (503)
9 Hans Holbein the Younger (555)
10 Johannes Vermeer (567)
11 Jacques-Louis David (607)
12 Giotto (610)
13 Diego Velázquez (693)
14 Gustave Courbet (965)
15 Hieronymus Bosch (983)

Top modern-era artists

VARIOUS                    
Top of the list … Vincent Van Gogh. Photograph: Rex Features

The Impressionist painters and their successors are at the top of our table of the most significant modern artists. Later movements such as surrealism (Salvador Dalí, 1,021) and abstract expressionism (Jackson Pollock, 1,013) are represented, but by relatively few artists.

1 Vincent van Gogh (73)
2 Pablo Picasso (171)
3 Claude Monet (178)
4 Henri Matisse (376)
5 Paul Cézanne (389)
6 Edgar Degas (422)
7 Andy Warhol (485)
8 Paul Gauguin (540)
9 Pierre-Auguste Renoir (549)
10 Auguste Rodin (574)
11 Wassily Kandinsky (618)
12 Edouard Manet (640)
13 Camille Pissarro (815)
14 Diego Rivera (915)
15 Edvard Munch (944)
16 James McNeill Whistler (1,002)
17 Jackson Pollock (1,013)
18 Salvador Dalí (1,021)
19 Piet Mondrian (1,051)
20 Georgia O'Keeffe (1,178)

Top 50 literary figures

Charles Dickens
At No 2 … Charles Dickens. Photograph: Getty Images

Ranking the world's greatest literary figures is a parlour game – just like the ranking of presidents or prime ministers. It exposes the biases inherent in everyone's world-view. But our ranking, it turns out, agrees with others: our top 50 contains 39 members of Daniel Burt's The Literary 100, including his 11 highest-ranked figures. With our Anglocentric source bias, we feature a larger number of British and US writers (but Jane Austen and Emily Dickinson are the only women to make it into the top 50).

1 William Shakespeare (4)
2 Charles Dickens (33)
3 Mark Twain (53)
4 Edgar Allan Poe (54)
5 Voltaire (64)
6 Oscar Wilde (77)
7 Johann Wolfgang von Goethe (88)
8 Dante Alighieri (96)
9 Lewis Carroll (118)
10 Henry David Thoreau (131)
11 Jane Austen (139)
12 Samuel Johnson (141)
13 Homer (152)
14 Lord Byron (158)
15 Walt Whitman (160)
16 John Milton (165)
17 Geoffrey Chaucer (173)
18 Virgil (177)
19 William Wordsworth (182)
20 Stephen King (191)
21 Emily Dickinson (194)
22 Leo Tolstoy (196)
23 Victor Hugo (208)
24 George Bernard Shaw (213)
25 Nathaniel Hawthorne (227)
26 Fyodor Dostoyevsky (244)
27 Miguel de Cervantes (246)
28 Ernest Hemingway (248)
29 HG Wells (249)
30 Herman Melville (251)
31 Rudyard Kipling (259)
32 Sophocles (274)
33 Samuel Taylor Coleridge (280)
34 John Keats (305)
35 Robert Burns (317)
36 Petrarch (326)
37 Percy Bysshe Shelley (329)
38 George Orwell (342)
39 Christopher Marlowe (374)
40 Thomas Hardy (378)
41 Aeschylus (386)
42 Jonathan Swift (391)
43 Rabindranath Tagore (397)
44 Henrik Ibsen (403)
45 James Joyce (406)
46 Henry James (408)
47 Aristophanes (418)
48 Alexander Pushkin (420)
49 Ben Jonson (421)
50 TS Eliot (436)

We generally score popular writers such as Oscar Wilde, Lewis Carroll and Mark Twain higher than we think the literary establishment would. We expect them to be surprised by our rank for horror novelist Stephen King. No other contemporary writer came close to a spot in our Literary 50. But we consider King to be the Dickens [33] of our time, characterised by immense popularity, mind-boggling productivity, and even the serial novel genre.

Who's Bigger: Where Historical Figures Really Rank by Steven Skiena and Charles B Ward is published by Cambridge.

Kepler Object of Interest From Wikipedia, the free encyclopedia

The Daily Galaxy  @dailygalaxy  15m  
"Kepler Object of Interest" --A Major Step in the Search for a Twin Solar System http://dailygalay.com  pic.twitter.com/xdAjFep76a
A Kepler Object of Interest (KOI) is a star observed by the Kepler spacecraft that is suspected of hosting one or more transiting planets. KOIs come from a master list of 150,000 stars, which itself is generated from the Kepler Input Catalog (KIC). A KOI shows a periodic dimming, indicative of an unseen planet passing between the star and Earth, eclipsing part of the star. However, such an observed dimming is not a guarantee of a transiting planet, because other astronomical objects—such as an eclipsing binary in the background—can mimic a transit signal. For this reason, the majority of KOIs are as yet not confirmed transiting planet systems.

History

The first public release of a list of KOIs was on 15 June 2010 and contained 306 stars suspected of hosting exoplanets, based on observations taken between 2 May 2009 and 16 September 2009. It was also announced that an additional 400 KOIs had been discovered, but would not be immediately released to the public. This was done in order for follow-up observations to be performed by Kepler team members.[1]

On February 1, 2011, a second release of observations made during the same time frame contained improved date reduction and listed 1235 transit signals around 997 stars.[2]

Naming convention

Stars observed by Kepler that are considered candidates for transit events are given the designation "KOI" followed by an integer number. For each set of periodic transit events associated with a particular KOI, a two-digit decimal is added to the KOI number for that star. For example, the first transit event candidate identified around the star KOI 718 is designated KOI 718.01, while the second candidate is KOI 718.02 and the third is KOI 718.03.[2] Once a transit candidate is verified to be a planet (see below), the star is designated "Kepler" followed by a hyphen and an integer number. The associated planet(s) have the same designation, followed by a letter in the order each was discovered.

Kepler data on KOIs

For all 150,000 stars being watched for transits by Kepler, there are estimates of each star's surface temperature, radius, surface gravity and mass. These quantities are derived from photometric observations taken prior to Kepler's launch at the 1.2 m reflector at Fred Lawrence Whipple Observatory.[3] For KOIs, there is, additionally, data on each transit signal: the depth of the signal, the duration of the signal and the periodicity of the signal (although some signals lack this last piece of information). Assuming the signal is due to a planet, these data can be used to obtain the size of the planet relative to its host star, the planet's distance from the host star relative to the host star's size (assuming zero eccentricity), and the orbital period of the planet. Combined with the estimated properties of the star described previously, estimates on the absolute size of the planet, its distance from the host star and its equilibrium temperature can be made.[1][4]

Sources of confusion

False positives

While it has been estimated that 90% of the KOI transit candidates are true planets,[5] it is expected that some of the KOIs will be false positives, i.e., not actual transiting planets. The majority of these false positives are anticipated to be eclipsing binaries which, while spatially much more distant and thus dimmer than the foreground KOI, are too close to the KOI on the sky for the Kepler telescope to differentiate. On the other hand, statistical fluctuations in the data are expected to contribute less than one false positive event in the entire set of 150,000 stars being observed by Kepler.[2]

Misidentification

In addition to false positives, a transit signal can be due to a planet that is substantially larger than what is estimated by Kepler. This occurs when there are sources of light other than simply the star being transited, such as in a binary system. In cases such as these, there is more surface area producing light than is assumed, so a given transit signal is larger than assumed. Since roughly 34% of stellar systems are binaries, up to 34% of KOI signals could be from planets within binary systems and, consequently, be larger than estimated (assuming planets are as likely to form in binary systems as they are in single star systems). However, additional observations can rule out these possibilities and are essential to confirming the nature of any given planet candidate.[2]

Verifying candidates

Additional observations are necessary in order to confirm that a KOI actually has the planet that has been predicted, instead of being a false positive or misidentification. The most well-established confirmation method is to obtain radial velocity measurements of the planet acting on the KOI.
However, for many KOIs this is not feasible. In these cases, speckle imaging or adaptive optics imaging using ground based telescopes can be used to greatly reduce the likelihood of background eclipsing binaries. Such follow-up observations are estimated to reduce the chance of such background objects to less than 0.01%. Additionally, spectra of the KOIs can be taken to see if the star is part of a binary system.[2]

Notable KOIs

KOIs with confirmed planets

As of December 5, 2011, Kepler had found 2326 planet candidates and 33 confirmed planets orbiting 19 stars.[6]

Previously detected planets

Three stars within the Kepler spacecraft's field of view have been identified by the mission as Kepler-1, Kepler-2, and Kepler-3 and have planets which were previously known from ground based observations and which were re-observed by Kepler. These stars are cataloged as GSC 03549-02811, HAT-P-7, and HAT-P-11.[7]

Planets confirmed by the Kepler team

Eight stars were first observed by Kepler to have signals indicative of transiting planets and have since had their nature confirmed. These stars are: KOI 7, KOI 18, KOI 17, KOI 97, KOI 10, KOI 377, KOI 72, and KOI 157. Of these, KOI 377 and KOI 157 have multiple planets (3 and 6, respectively) confirmed to be orbiting them.[7]

Planets confirmed by other collaborations

From the Kepler data released to the public, one system has been confirmed to have a planet, KOI 428b.[8]

KOIs with unconfirmed planets

Kepler-20 (KOI 70) has transit signals indicating the existence of at least four planets. If confirmed, KOI 70.04 would be the smallest extrasolar planet discovered around a main-sequence star (at 0.6 Earth radii) to date, and the second smallest known extrasolar planet after PSR 1257 12 b. The likelihood of KOI 70.04 being of the nature deduced by Kepler (and not a false positive or misidentification) has been estimated at >80%.

Six transit signals released in the February 1, 2011 data are indicative of planets that are both "Earth-like" (less than 2 Earth radii in size) and located within the habitable zone of the host star. They are: KOI 1026.01, KOI 854.01, KOI 701.03, KOI 268.01, KOI 326.01, and KOI 70.03.[2] A more recent study found that one of these candidates (KOI 326.01) is in fact much larger and hotter than first reported.[9]

A September 2011 study by Muirhead et al. reports that a re-calibration of estimated radii and effective temperatures of several dwarf stars in the Kepler sample yields six new terrestrial-sized candidates within the habitable zones of their stars: KOI 463.01, KOI 1422.02, KOI 947.01, KOI 812.03, KOI 448.02, KOI 1361.01.[1]

Non-planet discoveries

Several KOIs contain transiting objects which are hotter than the stars they transit, indicating that the smaller objects are white dwarfs formed through mass transfer. These objects include KOI 74, KOI 81 and KOI 959.[2][10]

KOI 54 is believed to be a binary system containing two Class-A stars in highly eccentric orbits with a semi-major axis of 0.4 AU. During periastron, tidal distortions cause a periodic brightening of the system. In addition, these tidal forces induce resonant pulsations in one (or both) of the stars, making it only the 4th known stellar system to exhibit such behavior.[11]

KOI 126 is a triple star system comprising two low mass (0.24 and 0.21 solar masses) stars orbiting each other with a period of 1.8 days and a semi-major axis of 0.02 AU. Together, they orbit a 1.3 solar mass star with a period of 34 days and a semi-major axis of 0.25 AU. All three stars eclipse one another which allows for precise measurements of their masses and radii. This makes the low mass stars 2 of only 4 known fully convective stars to have accurate determinations of their parameters (i.e. to better than several percent). The other 2 stars constitute the eclipsing binary system CM Draconis.[12]

References

  1. ^ Jump up to: a b Borucki, William J; et al. (2010). "Characteristics of Kepler planetary candidates based on the first data set: the majority are found to be Neptune-size and smaller". arXiv:1006.2799 [astro-ph.EP].
  2. ^ Jump up to: a b c d e f g Borucki, William J; et al. (2011-02-01). "Characteristics of planetary candidates observed by Kepler, II: Analysis of the first four months of data". http://kepler.nasa.gov. Retrieved 2011-02-10. 
  3. Jump up ^ Brown, Timothy M; et al. (2011). "Kepler Input Catalog: Photometric Calibration and Stellar Classification". arXiv:1102.0342 [astro-ph.SR].
  4. Jump up ^ Seager, Sara (2010). "Exoplanet Transits and Occultations by Joshua N. Winn". Exoplanets. University of Arizona Press. pp. 55–78. ISBN 978-0-8165-2945-2. 
  5. Jump up ^ Morton, Timothy D.; Johnson, John Asher (2011). "On the Low False Positive Probabilities of Kepler Planet Candidates". arXiv:1101.5630 [astro-ph.EP].
  6. Jump up ^ Kepler Discoveries NASA Accessed 3 January 2012
  7. ^ Jump up to: a b "Kepler Discoveries". NASA. 2011-02-08. Retrieved 2011-02-12. 
  8. Jump up ^ Santerne; Diaz; Bouchy; Deleuil; Moutou; Hebrard; Eggenberger; Ehrenreich et al. (2010). "SOPHIE velocimetry of Kepler transit candidates II. KOI-428b: a hot Jupiter transiting a subgiant F-star". arXiv:1101.0196 [astro-ph.EP].
  9. Jump up ^ Grant, Andrew (8 March 2011). "Exclusive: "Most Earth-Like" Exoplanet Gets Major Demotion—It Isn’t Habitable". 80beats. Discover Magazine. Retrieved 2011-03-09. 
  10. Jump up ^ Rowe, Jason F.; et al. (2010). "Kepler Observations of Transiting Hot Compact Objects". The Astrophysical Journal Letters 713 (2): L150–L154. arXiv:1001.3420. Bibcode:2010ApJ...713L.150R. doi:10.1088/2041-8205/713/2/L150. 
  11. Jump up ^ Welsh, William F; et al. (2011). "KOI-54: The Kepler Discovery of Tidally-Excited Pulsations and Brightenings in a Highly Eccentric Binary". arXiv:1102.1730 [astro-ph.SR].
  12. Jump up ^ Carter, Joshua A; et al. (2011). "KOI-126: A Triply-Eclipsing Hierarchical Triple with Two Low-Mass Stars". Science 331 (6017): 562–565. arXiv:1102.0562. Bibcode:2011Sci...331..562C. doi:10.1126/science.1201274. PMID 21224439. 

Further reading

Dear Einstein, Do Scientists Pray?

'Dear Einstein, Do Scientists Pray?' Asks Sixth Grader -- See His Amazing Response
                                                                                                                                                                                                                                                                                                                                                                                                                       







"Do scientists pray?"

That's the question that occupied the thoughts of a sixth-grade Sunday school class at The Riverside Church, and who better to pose it to than one of the best scientific minds of our time, Albert Einstein?
A young girl named Phyllis penned a polite and inquisitive note to the great physicist, and she was probably surprised to receive a considerate reply. The exchange was published in the book "Dear Professor Einstein: Albert Einstein's Letters to and from Children," edited by Alice Calaprice.
She wrote:
January 19, 1936
My dear Dr. Einstein,  
We have brought up the question: Do scientists pray? in our Sunday school class. It began by asking whether we could believe in both science and religion. We are writing to scientists and other important men to try and have our own question answered.
We will feel greatly honored if you will answer our question: Do scientists pray, and what do they pray for? 
We are in the sixth grade, Miss Ellis's class.
Respectfully yours,
Phyllis

He replied a mere five days later, sharing with her his thoughts on faith and science:
January 24, 1936Dear Phyllis,  
I will attempt to reply to your question as simply as I can. Here is my answer: 
Scientists believe that every occurrence, including the affairs of human beings, is due to the laws of nature. Therefore a scientist cannot be inclined to believe that the course of events can be influenced by prayer, that is, by a supernaturally manifested wish. 
However, we must concede that our actual knowledge of these forces is imperfect, so that in the end the belief in the existence of a final, ultimate spirit rests on a kind of faith. Such belief remains widespread even with the current achievements in science.  
But also, everyone who is seriously involved in the pursuit of science becomes convinced that some spirit is manifest in the laws of the universe, one that is vastly superior to that of man. In this way the pursuit of science leads to a religious feeling of a special sort, which is surely quite different from the religiosity of someone more naive. 
With cordial greetings,
your A. Einstein

While the letter doesn't reveal much about Einstein's own personal views on religion, he brilliantly manages to capture the the sublime sense of wonder that science can evoke in a way that it's possible to describe as "religious."

Josh Jones of Open Culture commented, "I think it’s a moving exchange between two people who couldn’t be further apart in their understanding of the world, but who just may have found some small common ground in considering each other’s positions for a moment."

Fundamental laws - Astronomical reach

Posted Jan 31, 2014By Catherine Zandonella, Office of the Dean for Research
Jeremiah Ostriker directs his efforts toward theories of dark matter and dark energy, galaxy formation, and other fundamental questions. He served as provost of Princeton University from 1995 to 2001. His recent book is Heart of Darkness: Unraveling the Mysteries of the Invisible Universe (with science writer Simon Mitton, Princeton University Press, 2013). Photo by Denise ApplewhiteJeremiah Ostriker directs his efforts toward theories of dark matter and dark energy, galaxy formation, and other fundamental questions. He served as provost of Princeton University from 1995 to 2001. His recent book is Heart of Darkness: Unraveling the Mysteries of the Invisible Universe (with science writer Simon Mitton, Princeton University Press, 2013). Photo by Denise Applewhite
 
We live in a world of very small things (atoms) and very large things (stars, galaxies). How can the same laws of nature describe such different objects? Two people who have given the matter some thought are Adam Burrows and Jeremiah Ostriker, both professors of astrophysical sciences at Princeton University.

Their new paper, "Astronomical reach of fundamental physics," published this week in the Proceedings of the National Academy of Sciences, explains how fundamental physical laws can describe objects that are as small as an atom or as massive as a galaxy. This exercise illustrates the unifying power of physics and the profound connections between the small and the large in the cosmos we inhabit. The fundamental laws of nature, the researchers say, have amazing consequences.
Professors Ostriker and Burrows spoke with interviewer Catherine Zandonella of the Office of the Dean for Research at Princeton University.
 
List to the interview in this podcast or read the transcript below.
Download the podcast (.mp3) for later listening.
 
What made you decide to look at the astronomical reach of fundamental physics?
Adam Burrows' interests range from the theory of supernova explosions to the atmospheres of extra solar planets, brown dwarfs, and high-energy astrophysics. (Photo by Keren Fedida)Adam Burrows' interests range from the theory of supernova explosions to the atmospheres of extra solar planets, brown dwarfs, and high-energy astrophysics. (Photo by Keren Fedida)
 
Adam Burrows: One of the things you notice when you are doing general physics is that things are connected in ways that people don't always recognize. You study quantum mechanics or relativity; you are focused on various aspects of the small or the fast, etc.

But when you do astrophysics, you look at these things fairly broadly, and you incorporate the disparate realms of physics that you find in the laboratory, and apply it, in as many ways as you can, in the large.
 
What you find is that those things involved with the very small — such as quantum mechanics and atoms and molecules and nuclei — and those that deal with the very large things, and even those with which we are familiar, having to do with gravity and the gravitational attractions, when combined together, actually can inform just about everything in the Universe.
 
This particular paper was motivated by many things, but one thing at least in my mind was to bring together the simple arguments that show that there's a unity to science, and that the things that the people in the physics department might study — whether involved with Planck's constant or the speed of light, or the charge of the electron, things that involve fairly small objects — actually can explain in some detail the largest things in the Universe: stars in particular, but also galaxies, clusters of galaxies.
 
Life itself in principle can be explained in simpler terms, and it is that simplicity that underlies the complexity around us that we wanted to articulate as best we could.
 
Jeremiah Ostriker: I agree with all of that but would give quite a different answer.
If you take books that were written in the first half of the 20th century, about science, they often gave back-of the envelope arguments — simple arguments to explain how many atoms there were in a star, how many atoms there would be in the Universe. And people were used to thinking in very simple order-of-magnitude ways, and that informed physics, and that informed science. (Enrico) Fermi was famous for asking questions of his students, so they could give really simple answers.
It has gone out of fashion. Right now the students think that the answers only come out of gigantic calculations on supercomputers.
 
The details may come from that, but the essential elements have to be simple. All masses have to be related to one other: they have to be so many protons, or so many electrons.
And so we thought it would be useful to go over again the early work that people have done on how you can understand things in a very, very simple way, and also to update it with new things that have been discovered.
 
So, why are most galaxies between here and here, there are none bigger than this, and none smaller than that? There must be some good reason for that, and if you think about it, there are good reasons for it.
 
Burrows: I like that answer, too.
 
What made the two of you decide to look at this together?
Ostriker: We have both done calculations in the past. I'm not sure either of us has published them.
 
Burrows: No, that is true.
 
Ostriker: So we talked about it, and then we thought it would be fun to write a paper together.
Burrows:  These sorts of questions having to do with astronomical objects and the basic physical underpinnings can be addressed, and there is a whole tradition of making this connection.
And in this paper we wanted to bring together many of these arguments, update them, and provide them to the cognizant audience that might be interested in them. In fact, we found quite a bit of interest.
 
Ostriker: It is interesting that stars can only exist in a certain range. They cannot be less than this or more than that. Planets, ditto: if you make a planet bigger it starts to burn and becomes a star — it is not a planet anymore. If you take a galaxy and try to make it bigger, it becomes a cluster of galaxies, not a galaxy. If you try to make it smaller than that, it seems to blow itself apart.
 
To understand why things are as they are, is what the Greeks understood as science and what we still do, and to bring these arguments together seemed valuable.
 
What does it tell us about what the Universe is? What reality is? What we are?
Burrows: One of the things that it tells us is that in fact the Universe is quantifiable. There are natural laws that apply in the small and the large. There is a detailed understanding of the mechanism of the Universe.
 
That sounds a little grand, but everywhere we look we can explain with physical principles. Whether they are applied to small objects or large objects, we can apply these principles to determine many of their properties and understand them in great detail.
 
The Universe and the world follow natural laws and are explainable and are quantifiable on all scales.
 
Ostriker: So, if you go out at night with your child or grandchild and you see the stars, and your child asks why are they that brightness? Why are they bright enough for us to see? Why aren't they so bright that they burn out our eyes? Why isn't the Earth 100 times bigger in size? These are the questions that bright kids might ask.
 
Burrows: I hope that bright kids will eventually read these articles, because there is a whole tradition of doing these simple studies to connect things. And it is "connection" that is the important word in all of this.
 
People sometimes have lost the connectivity of the various sciences. They stovepipe things into chemistry, and biology, and aspects of physics, but what an astrophysicist does and should attempt to do at all times is to integrate these different disciplines to solve the problems that he or she encounters.
 
And you can do so. You can bring the statistical physics and quantum mechanics and relativity and gravitational physics together, as the Universe does effortlessly, to explain things that wouldn't have otherwise been explained, but with simple arguments.
 
It is the simplicity of the basic arguments that underlie many of these objects that we wanted to articulate and communicate.
 
Ostriker: (Subrahmanyan) Chandrasekar, who was my teacher, said there is a maximum mass for a white dwarf, a type of star. Well, nobody has ever found one higher than that mass, so he was right, there is a simple argument for it.
 
So, in many of these cases, the understanding was sufficiently good that people were able to make predictions, and then, all the coincidences that the observer would notice, you could understand them.
And that's the magic.
 
Burrows: The "Chandrasekar mass" to which Jerry is referring can be derived in terms of Avogadro's number, which we associate with chemistry; Planck's constant, which we associate with quantum mechanics and the systematics of the small; the speed of light; and Newton's gravitational constant.
 
You bring these things together, you shake appropriately, and you can explain this particular phenomenon, and see that Chandrasekar was perfectly right. But you can see where it comes from, fundamentally, at the nexus of many of the great tributaries of physics over the last 100 years.
 
Do you think it will be possible to explain different aspects of life?
Ostriker: Biology has tended to be an observational science and deriving things from first principles has not been possible in the past but I hate to predict the future on that.
 
Burrows: It may well be that we have enough physical knowledge, but biology is so complex, and we have to unravel the complexity.
 
Think of all the progress that has been made on the genome and the connectome and all of the big data, bioinformatic revolutions that people hear about. This is an indication that people are starting to come to grips with the complexity that is inherent in life.
 
What do you think these findings mean for the average person?
Ostriker: If we had wanted to write this for high school students, I think we could have. You can do it all with high-school math. You need elementary math but not more.
 
Burrows: This is a way of reaching across what has been a divide, to encourage the view that science is an integrated and broad enterprise, and everyone contributes.
 
The paper, "Astronomical reach of fundamental physics," by Adam S. Burrows and Jeremiah P.
Ostriker, was published in the Proceedings of the National Academy of Sciences (Early Edition) on January 29, 2014. doi: 10.1073/pnas.1318003111. PubMed ID24477692.

The Wisdom of Socrates



Keep this in mind the next time you are about to repeat a rumour or spread gossip.


In ancient Greece (469 - 399 BC), Socrates was widely lauded for his wisdom.

One day an acquaintance ran up to him excitedly and said, "Socrates, do you know what I just heard about Diogenes?"

"Wait a moment," Socrates replied, "Before you tell me I'd like you to pass a little test. It's called the Triple Filter Test."

'Triple filter?" asked the acquaintance.

"That's right," Socrates continued, "Before you talk to me about Diogenes let's take a moment to filter what you're going to say. The first filter is Truth. Have you made absolutely sure that what you are about to tell me is true?"

"No," the man said. "Actually I just heard about it."

"All right," said Socrates, "So you don't really know if it's true or not. Now let's try the second filter, the filter of Goodness. Is what you are about to tell me about Diogenes something good?"

"No, on the contrary..."

"So," Socrates continued, "You want to tell me something about Diogenes that may be bad, even though you're not certain it's true?"

The man shrugged, a little embarrassed.

Socrates continued: "You may still pass the test though, because there is a third filter, the filter of Usefulness. Is what you want to tell me about Diogenes going to be useful to me?

"No, not really."

"Well," concluded Socrates, "If what you want to tell me is neither True nor Good nor even useful, why tell it to me or anyone at all?"

The man was bewildered and ashamed.

This is an example of why Socrates was a great philosopher and held in such high esteem.

It also explains why Socrates never found out that Diogenes was shagging his wife.

More About Australia's Possible Endangering the Great Barrier Reef

Great Barrier Reef Sediment
Daniel Osterkamp via Getty Images

     



                            



SYDNEY (AP) — The government agency that oversees Australia's Great Barrier Reef on Friday approved a plan to dump vast swathes of sediment on the reef as part of a major coal port expansion — a decision that environmentalists say will endanger one of the world's most fragile ecosystems.

The federal government in December approved the expansion of the Abbot Point coal port in northern Queensland, which requires a massive dredging operation to make way for ships entering and exiting the port. About 3 million cubic meters (106 million cubic feet) of dredged mud will be dumped within the marine park under the plan.

Environment Minister Greg Hunt has vowed that "some of the strictest conditions in Australian history" will be in place to protect the reef from harm, including water quality measures and safeguards for the reef's plants and animals.

But outraged conservationists say the already fragile reef will be gravely threatened by the dredging, which will occur over a 184-hectare (455-acre) area[that is 0.7 squares miles, or a mere 0.0005% of the total Reef area]. Apart from the risk that the sediment will smother coral and seagrass, the increased shipping traffic will boost the risk of accidents, such as oil spills[I thought they were shipping coal which presents very little risk, even if there is an accident]and collisions with delicate coral beds, environment groups argue.

On Friday, the Great Barrier Reef Marine Park Authority — the government manager of the 345,400 square kilometer (133,360 square mile) protected marine zone — approved an application by the state-owned North Queensland Bulk Ports Corp. for a permit to dump the sediment within the marine park in a location that does not contain any coral or seagrass beds.

Bruce Elliot, general manager for the marine authority's biodiversity, conservation and sustainable use division, said in a statement that strict conditions would be placed on the sediment disposal, including a water quality monitoring plan that will remain in place five years after the dumping is complete.

"By granting this permit application with rigorous safeguards, we believe we are able to provide certainty to both the community and the proponent while seeking to ensure transparent and best practice environmental management of the project," Elliot said.

The ports corporation's CEO Brad Fish has argued that the sediment has been extensively tested for contaminants and was found to be clean.

"This is natural sand and seabed materials ... it's what's already there," Fish said in an interview last month. "We're just relocating it from one spot to another spot, in a like-per-like situation."
Rachel Campbell, spokeswoman for the ports corporation, said the group didn't anticipate the conditions would cause any delays to the dredging plans.

Australia is home to vast mineral deposits and a mining boom fueled by demand from China kept Australia's economy strong during the global financial crisis. Though the boom is now cooling as demand from China slows, Prime Minister Tony Abbott and his conservative government have vowed to focus their efforts on reviving the industry.

In a report released in 2012, UNESCO expressed concern about development along the reef, including ports, and warned that the marine park was at risk of being listed as a World Heritage site in danger.

In response, Queensland Premier Campbell Newman said his government would protect the environment — but not at the expense of the state's economy.

"We are in the coal business," he said at the time. "If you want decent hospitals, schools and police on the beat we all need to understand that."

Environmentalists were infuriated by Friday's decision, saying that the reef is already vulnerable, having lost huge amounts of coral in recent decades to storm damage and coral-eating crown of thorns starfish.

"We are devastated. I think any Australian or anyone around the world who cares about the future of the reef is also devastated by this decision," said Richard Leck, reef campaign leader for international conservation group WWF. "Exactly the wrong thing that you want to do when an ecosystem is suffering ... is introduce another major threat to it — and that's what the marine park authority has allowed to happen today."

Shale Gas: The Northeast Game Changer


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Over the past few years, natural gas has taken the energy sector by storm in the United States. The newly discovered technology allowing for efficient extraction and production of shale gas has rejuvenated the energy sector in the U.S., putting the country in a leading position in the global energy market. According to the U.S. Energy Information Administration (EIA), U.S. natural gas production–which was 23.0 trillion cubic feet in 2011–is projected to surge by 44% to 33.1 trillion cubic feet by 2040. This substantial increase in U.S. domestic production is largely due to a massive rise in shale gas production in particular. The improved extraction technology of shale gas in recent years has enabled the U.S. to produce more natural gas than it consumes and to rely almost wholly upon its own domestic supply.

The Shale Evolution
Shale gas refers to natural gas that is trapped within shale formations–fine-grained sedimentary rocks which can be abundant sources of petroleum and natural gas. In the past, releasing this gas from shale was a problematic process—one that was both costly and technically challenging. However, new advances in horizontal drilling and hydraulic fracturing over the past ten years have made it possible to access large volumes of shale gas. Previously, accessing this gas would have been economically infeasible. Now, U.S. shale gas production comprises about 40% of the country’s total dry production; moreover, shale gas production is projected to rise by a staggering 44% by 2040 (Figure 1).1
enter image description here
Figure 1: Changes in U.S. Dry Natural Gas Production | Data Source: EIA

Increased Northeast Production
From 2008 to 2013, natural gas production in the northeastern United States has increased more than five times, from 2.1 billion cubic feet per day (Bcf/d) to 12.3 Bcf/d.2 This additional supply has supported greater use of natural gas in the Northeast (especially for commercial users like power generation stations) while reducing the net inflows of natural gas from other regions such as the Gulf of Mexico, the Midwest, and eastern Canada.
enter image description hereFigure 2: Northeast Production vs. Nat Gas inflow | Data Source: EIA

Although there are six regions that produce the majority of shale gas (plays) in the U.S. (Bakken, Niobrara, Permian, Marcellus, Eagle Ford, and Haynesville), the Marcellus region alone accounted for about 75% of natural gas production growth among all regions. In December 2013, the Marcellus region, located in Pennsylvania and West Virginia, is expected to provide 18% of total U.S. natural gas production.3Although vast shale plays in the Marcellus region have a major role in the rapid development of U.S. natural gas production, the improved efficiency of new wells has also played a significant role in increasing production volumes. Despite the declining number of drilling rigs in the region since 2012, production from wells has continued to grow. Marcellus wells have begun producing higher volumes due to the removal of resource constraints in the takeaway capacity as a result of the discovery of abundant shale plays, along with recent infrastructure upgrades in West Virginia and Pennsylvania (Figure 3).
enter image description hereFigure 3: Marcellus Rig Count vs. Production | Data Source: EIA

Since 2012, production growth in the northeast region has driven the future prices of natural gas at the Columbia Gas Transmission Appalachia hub below Louisiana’s Henry Hub prices on the New York Mercantile Exchange (NYMEX). The graph below (created in ZEMA with data from NYMEX) shows the drop in futures prices for the Columbia Gas Transmission Appalachia hub in the Northeast region compared to Henry Hub futures. This drop is most notable since January 2012 (Figure 4).
enter image description hereFigure 4: Henry Hub Natural Gas vs. Columbia Gas Appalachia Futures | Data Source: NYMEX

Shale Gas and the Global Landscape
In June 2013, a joint EIA/Advanced Resources International study reported that China is the only country outside of North America that has registered commercially viable production of shale gas, although China’s commercially viable volumes contribute less than 1% of the total natural gas production of the country.4This means that the U.S. and Canada are the largest producers of natural gas from shale formations in the world. In 2012, U.S. shale gas production (25.7 Bcf/d) as a share of total natural gas production (65.7 Bcf/d) was 39.1%, whereas this number for Canada was 14.3% (Figure 5).
enter image description hereFigure 5: Shale gas as share of total dry natural gas production | Data Source: EIA

In 2012, Canadian shale gas production from two major shale plays—Horn River and Montney— averaged 2.0 Bcf/d, whereas the total Canadian production averaged 14.0 Bcf/d. Gross withdrawals from Horn River and Montney averaged above 2.5 Bcf/d in 2013, but higher production levels are currently constrained by limited pipeline infrastructure (Figure 6). Comparing the two major shale plays of Canada and the Marcellus region, the production from the Marcellus shale plays is expected to reach above 6.0 Bcf/d by the end of 2013 (Figure 3), whereas Canadian production is less than half of that level.
enter image description hereFigure 6: Gross Withdrawals from select shale plays in Canada (Jan 2005 - May 2013) | Data Source: EIA

Shale Gas Production and Environmental Concerns
The combustion of natural gas emits significantly lower levels of carbon dioxide (CO2) and sulfur dioxide than does the combustion of coal or oil. Furthermore, natural gas combustion can emit less than half as much CO2 as coal combustion (per unit of electricity output) when used in efficient combined-cycle power plants. Hence, natural gas is cleaner fuel than coal or oil, although it is far from being environmentally friendly!

Natural gas is not wholly environmentally friendly for several reasons. First of all, a large amount of
water is needed for the fracturing of wells in shale gas production, which affects the availability of water in surrounding areas for other uses while negatively affecting native aquatic habitats. Secondly, water, toxic chemicals, and sand used in hydraulic fracturing fluids can contaminate surrounding areas if managed poorly—that is, if spilled or leaked due to human error, or discharged as a result of faulty well construction. Additionally, the water waste that occurs as a byproduct of fracturing requires a lot of care when treated and disposed, as it is extremely toxic. Finally, according to the United States’ Geological Survey, hydraulic fracturing occasionally causes small earthquakes that are not a safety concern. If wastewater from the fracturing process is injected into deep wells in the subsurface of the earth, though, larger earthquakes that are a safety threat may occur.

Final Words
Although shale gas production has entered a new phase in North America since 2010, the Northeastern United States has the largest growth in natural gas production due to its massive shale reservoirs. The Marcellus plays (in the Northeast between Pennsylvania and West Virginia) are awash with shale reserves that have changed market dynamics. Historically, natural gas prices in the Northeast were high because of the high demand of the region. However, increased production due to the abundant shale plays and infrastructure upgrades in the Marcellus region have pushed down domestic natural gas prices in the U.S. and have reduced imports from other regions. Plus, natural gas is a cleaner fuel to consume when compared to oil and coal, which makes it more desirable for power plant operators in the Northeast region. Typically, cold temperatures and a high population density in this region have exerted upward pressure on electricity prices; however, the boom in Northeastern natural gas resources may lower electricity prices in this region. Nevertheless, the hydro fracturing procedures used in the production of shale gas would not make shale gas less environmentally damaging than any other fossil fuel.

In brief, the Northeast is sitting on a wealth of shale gas reserves that have changed energy trading for the region and the U.S. as a whole. The shale gas boom has even caused oil producers in the Middle East to carefully follow the rise of shale gas production in the U.S., as the country’s appetite for petroleum could be seriously affected by this phenomenon. It is interesting to speculate as to whether the shale gas boom in the U.S. may be the silver bullet for the Land of the Free in its present economic situation!

At ZE, we collect, analyze, and integrate data from all global natural gas hubs. Our award winning software, the ZEMA Suite, is an end-to-end enterprise data management solution for energy, commodity, and financial market participants that helps organizations manage data efficiently.
Please contact us to suggest a topic for analysis or book a complimentary demo of the ZEMA Suite software.

-Ryan Arian, ZE Perspective

Lie group

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Lie_group In mathematics , a Lie gro...