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Psychology and Thermodynamics...

The sculpture above is Salvador Dali’s “Dance of Time II” displayed in front of the ArtScience Museum at Marina Bay Sands in Singapore. (Inside Science)

(ISNS) -- Almost nothing is more obvious than the fact that time flows from the past, which we remember, toward the future, which we don’t. Scientists and philosophers call this the psychological arrow of time. Hot coffee left on your desk cools down, and never heats up on its own, which reflects the thermodynamic arrow of time.



In a paper scheduled to appear this week in the journal Physical Review E, two physicists make the case that these two long-separate notions of time — one based on psychology and one based on thermodynamics — must always align.



The principles of thermodynamics show that large collections of particles, like the trillions upon trillions of liquid molecules in a coffee cup, always move toward more disorganized arrangements. For instance, hot water molecules clumped together in a cold room need a lot of organization, so warm drinks eventually cool to the surrounding temperature. Physicists say such disorganized arrangements have high entropy, whereas ordered arrangements have low entropy.



Good primer on the subject, and an attempt to bridge the philosophy with the physics. As I've stated to someone that's asked me about why backwards time travel isn't possible, my answer is it hasn't been observed in nature. We would see teacups or chandeliers "un-break" or waterfalls flow backwards. It would be quite visible and noticeable from the norm, I would think. If it were possible, we could have visitors from the future creating paradoxes that would wreck havoc to the timeline - someone would notice that as well.



Inside Science: Why Does Time Flow Forward? Gabriel Popkin, ISNS Contributor

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Diversity...



From the image source at Nature:

"Science remains institutionally sexist. Despite some progress, women scientists are still paid less, promoted less frequently, win fewer grants and are more likely to leave research than similarly qualified men. This special issue of Nature takes a hard look at the gender gap — from bench to boardroom — and at what is being done to close it."



Unfortunately, the world is not like Star Trek, populated with fictional Captains like Kathryn Janeway of this inspiring description:



"This subject's penchant for the scientific method and clear-cut choices has given her a healthy dose of skepticism, which usually provides a command asset in dealing with new situations. Her preference for difficult studies is self-traced back to childhood, when she would prefer that to outdoor play. Since then, she has indicated no pleasure in outdoor camping, hiking, or cooking." StarTrek.com



I follow a blog: Female Science Professor. The author describes herself as a full professor, and other than staying anonymous (probably important around review time) she's very frank about the biases encountered both from colleagues and students: her most resent post, a student in class evaluation said "You should improve your teaching methods." The prof made lemons into lemonade and blogged about it. The genders of her students - like her own identity - were left nebulous.



Diversity: an ideal we all agree sounds good on paper, but are reluctant to do the heavy lift to achieve it (see Nature excerpt). Even in politics: our current president as probability represents 2.3% of the general population of Chief Executives from George Washington to himself. However, disrespect of the office and obstruction of his agenda approaches Guinness World Record levels as he's being sued for using Executive Orders - the least of any president according to official archives and math - essentially the pre-pubescent, sidewalk-flailing public tantrum of a desperate orange man being any Executive Order above zero.

Women and minorities are not only underrepresented in the sciences, they are openly discouraged from pursuing STEM careers at the university level and at early life stages. I was personally insulted by my middle school science teacher - "No, you big dummy!" - after asking a question about calculating the coefficient of linear expansion on a metal wire. I had stifled the immediate urgent need at that moment to deck him, confident of the outcome with the authorities if I had. My parents were not amused, and scheduled a visit with the principal. That was followed by a sweaty, self-preserving "apology" from the science teacher. I passed his class with a descent grade, and moved on from the twerp. The fact both groups are so low means discouragement is remarkably efficient to maintain the status quo of the "usual suspects" in the sciences, and a concentration of wealth and opportunities along gender and cultural lines. Suffice to say, to resist the "haters": you have to want it!

Albert Einstein was so fond of answering the fan mail of children interested in science, author Alice Calaprice wrote a book on it. In an exchange with a young science fan from South Africa named Tiffany:

September 19, 1946: "I forgot to tell you, in my last letter, that I was a girl. I mean I am a girl. I have always regretted this a great deal, but by now I have become more or less resigned to the fact. Anyway, I hate dresses and dances and all the kind of rot girls usually like. I much prefer horses and riding. Long ago, before I wanted to become a scientist, I wanted to b e a jockey and ride horses in races. But that was ages ago, now. I hope you will not think any the less of me for being a girl!"

To which, Einstein's reply was classic, and classy (circa October 1946):

"I do not mind that you are a girl, but the main thing is that you yourself do not mind. There is no reason for it."


Carl Sagan pointed out there is an excellent correlation between poverty for women and high birthrates, whether the country is defined by religion - Christian, Hindu, Irreligious,  Muslim, etc. That would suggest access to birth control increases the wealth of women and nations, unless you're a Corporation-Person that can presumably give obeisance from bricks to deity. Or, you're five male, activist Catholic Supreme Court Justices intent on cramming their Neanderthal viewpoints down everyone's throats. The caveat emptor is in dismantling the legal fiction and protections forming corporations give. Someone is going to sue a business in the future siting this so-called ruling, coming after the owner or owner's personal wealth also. Slippery slopes forge unintended pathways.

Minorities (an ironic label for the majority of the Earth's population) at least numerically in this country are hampered by generations of specifically-designed social engineering; castigated for not competing in rigged "rights" of citizenship (like voting); when the value of property plummets at their presence; the neurological harmful effects of leaded plumbing in East Austin and other areas not addressed until gentrification (and now I see climate effects); globalization and technology eliminating previous decent-paying jobs, doubled unemployment rates and the obvious differences dependent on which side of the tracks you were born (still) in education since Brown vs. Board. It's also interesting to see screeds on the Internet against the LGBT community, unbeknownst to the screed producer of the Turing Test for artificial intelligence, or that he's the reason we have in the lexicon "algorithm"; "computation"; "cryptography" (the essence of McAfee, Norton or any antivirus software), or as the father of Computer Science that we're typing on laptops at all. Not to mention the ugly, breathtaking displays of xenophobia at the border of California to children by the great-great-grandchildren of immigrants that have yet to recompense the Native Americans for the sins of Columbus.



We can have myriad months of celebrations that target specific groups and their contributions. It all disappears into the social, attention-deficit ether. Our discourse, our academia, our music, our self-governance; our sense of right-and-wrong (who goes to prison and who goes to rehab) will not change nor will we survive as a species until we see one another...as humans.

Related link: Go-Girl - Gaining Options-Girls Investigate Real Life
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Anthony Hall, Founder of TREOProposing to build an innovation lab and academy in Africa to develop prototypes of a flying surfboard simulation, spoken word programming language and the Iron Roses WING FS [Wave Integrated Null-G Flying Suite].Flying (Silver Surfer style) simulations, systems and suits - you heard it here first.---The Rose of Education Organization [TREO]Where Education is Child's Play and Technology is a Game
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Very Large Array...


Kinda nerdy, 1st-hand description (embed):


The Very Large Array, one of the world's premier astronomical radio observatories, consists of 27 radio antennas in a Y-shaped configuration on the Plains of San Agustin fifty miles west of Socorro, New Mexico. Each antenna is 25 meters (82 feet) in diameter. The data from the antennas is combined electronically to give the resolution of an antenna 36km (22 miles) across, with the sensitivity of a dish 130 meters (422 feet) in diameter. 
For more information, see our overview of the VLA, and the configuration schedule.
 

We will be offering our regular guided tours of the VLA every first Saturday of the month, from 11AM to 3PM.

Site: National Radio Observatory

Tomorrow: Diversity

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SPS Interns...



My youngest has an internship with a Civil Engineering firm in Arlington. That fact fills me with pride, and some financial relief as he pays his own rent this summer.

However, the following both filled me with parental puff, and gave me pause:

STEM learning is critical to a 21st century education, but there remains a serious mismatch of skills for entering the workforce.  According to data from the Ray Marshall Center’s Student Futures Project, in 2012 only 21 percent of students in Central Texas graduated with an interest in an Engineering, Computer & Information Services, or Natural Sciences & Mathematics post-secondary program.  Further, research suggests that students indicating a preference for a STEM career by the eighth grade are two to three times more likely to earn STEM degrees than their peers.

By the ninth grade, he entered and matriculated through something called an "Architectural Passport" program until he graduated. He initially wanted to be an architect or go into architectural engineering. Civil engineering was the closest at UT Arlington, and the firm he works for works in structural engineering, which is essentially what AE's would do. He's having a lot of fun.

This statistic from the STEM council troubles me as employers are starting to hire Central Texans again in STEM fields. To feed this pipeline, it would behoove them to increase this percentage. If you're in Civil Engineering, the ASCE site probably is your best bet. For all us physics nerds, here's a little help below.

Note: For SPS - Society of Physics Students - internships, applications due February 14.
(Valentine's Day massacre? Couldn't resist).

Stipend: $4,500.

Also covers: commuting allowance, coverage of transportation to/from Washington, DC, and support to attend and present at a national physics meeting in the year following the internship.

Meet the 2014 SPS National Interns, who are in the Washington, DC, area for 9.5-week science, policy and outreach internships with organizations including SPS, AIP, AAPT, APS, NASA, NIST, and the U.S. House of Representatives, May 28 - August 1, 2014.


More info:
2014 SPS National Interns
SPS Internships (good luck)

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The Whitewashing of Hollywood

Whitewashing Was One Of Hollywood's Worst Habits. So Why Is It Still Happening?

It probably won't surprise you to learn that early Hollywood's mainstream films were far from racially, ethnically or culturally sensitive. When minority characters were represented at all, they were typically characterized as immoral, criminal simpletons, used as comedic contrasts to their white protagonists, as outlined in the book Racism, Sexism, And the Media. Meanwhile, Hollywood's mainstream starring roles have long been monopolized by white actors; even though it's meant whitewashing history. What may surprise you is how frequently this still happens today.

Click here for the full story

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Solar Sails...

Source: NASA Science News

"Provide ships or sails adopted to the heavenly breezes, and there will be some who will brave even that void..." Johannes Kepler in a letter to his friend Galileo, 1610

Related to the topic (and mentioned in the live stream - see the Space.com link below):



Unlike chemical and rocket systems, which must expell a propellant to create thrust, an electrodynamic tether generates thrust through Lorentz-force interactions with a planetary magnetic field. By using the space environment to create thrust, electrodynamic tether systems can dramatically reduce the cost of many space missions by eliminating the need to launch large quantities of propellant into orbit.



An electrodynamic tether is essentially a long conducting wire extended from a spacecraft. The gravity gradient field (also known as the "tidal force") pulls the tether taut and tends to orient the tether along the vertical direction. As the tether orbits around the Earth, it crosses the Earth's magnetic field lines at orbital velocity (7-8 km/s!). The motion of the conductor across the magnetic field induces a voltage along the length of the tether. This voltage, which is called the "motional EMF", can be up to several hundred volts per kilometer.

Related links:
#P4TC: "Fly Me to the Moon" (and beyond)...March 4, 2011
Planetary Society: Light Sail Update: Of Booms and Pretty Pictures
Space.com: NASA Solar Sail Announcement (live streamed last night)
Sunjammer Mission: The Sun is Us
Tethers.com: Tethers Unlimited

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Quantum Field Theory...

Source of photo, text and lectures: PhysicsDatabase.com

Ok so it seems like a good time to update the lecture section. Here we have a full course on quantum field theory. Ed Witten, when asked about quantum field theory, described it as the hardest theory in modern physics by far. However my friends, don’t be discouraged, there are plenty of great resources online that can help you out in taming this hard theory. One of the best resources is this course delivered by David Tong. The course contains 14 lectures focusing on the basics of QFT. The only obvious drawback is, as you might have noticed, the quality of these videos. Luckily, the videos can be downloaded in various formats (including the slides showing the blackboard) on the Perimeter Institute website. For more lectures visit the links below.
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I am sooo looking forward to this book hitting the shelves. Those that know how I work, I don't read the manuscripts I create covers for. I get pertinent information straight from the author.  I do, however, get a bit more of a glimpse than what's offered in the blurb. Rachel sent me an excerpt that described the spider-like figures, but I need to discover how they ambulate. I just know Rachel was vague about it on purpose, lol. 
 
blurb:

When Erest ventures onto the forbidden mountain of the dead gods, he finds himself snared only half-willingly into the service of the last goddess in the world. The Kieba does need help in her endless work of guarding the world from plague and disaster, but does that really have to be him?

Oressa, princess of Carastind, knows what’s important in life:  avoiding her royal father and keeping track of all the secrets of his court.  But when she overhears news about imminent invasion, she is shocked to discover just what her father plans to give away in order to buy peace.

But when the invaders attempt to steal the Kieba’s power, both Trei and Oressa must decide where their loyalties actually lie, and what they are willing to risk to protect the goddess, their home, and the world.

Once I have a release date and purchase links, I'll post then to my website on the book's page:
http://willowraven.weebly.com/mountain-of-kept-memory.html


Onto wrapping up the next book :D

Until next time ...


This post edited by*: Seven errors were remedied.


*Blurbs and quotes provided are not edited by WillowRaven, but posted as provided by author/publisher. 
 
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Keep your head to the skies

Keep your head to the skies is what the music said, so that was the message I heard. I don't know if that was right. My daughter said keeping all my long for you. I said love baby not long. We laugh at that now. A lot of messages depend on what you already heard for context and reality.

On the Men in Black, they said ever notice how beautiful the stars are? An obvious sign they were tired of their job and wished they didn't have carnal knowledge of aliens. I don't know I never look up. Where's that flashy thing. You do know a laser across the eyes will wipe out memory, careful watching that media, subliminal flashes will.............

In the Matrix Neal said no one remembers when we scorched the sky. Which brings me to my point, why life is so weird. There be multiple drapes pulled over our eyes. Each institution has a stage and we participate in their production according to their script. It is a mental play in which the words define the reality and the cast members all concur and are in cahoots. How angry we get when the cast members of another play acts as if his play has better reviews than ours. He is a star in his own mind, but then so are you, in your mind. Diversity is how to live peacefully with others on different pages of the same book. Reading or insisting on a different book is an act of war.

The scripts are real, we treat them as holy rituals and dress for the part. Meanwhile chem-trails crosshatch the sky. We should say planes are putting out pollutions in mega proportions but chem-trails are urban legend like spacecraft. It's swamp gas or water vapor. I remember the skies of my youth and airplanes of lower technology that didn't make lingering spreading linear clouds. You mean to tell me with today's efficient technology and clean fuels the sky is a woven blanket of harmless visible water vapor?

I used to walk through the same wall out of habit, I stopped because a residue left behind each time started to show signs of organizing into a new life form. LOL! Now I am concerned, is not my form who I am or is there a part of me that can not slip between space or other forms intact. I was thinking of visiting an hospice for superheros to find out what becomes of the aged.............oops, forgot, the comics are another one of those scripts. Stan still and know I am god, who said that? Another script? The powers that be have been applied in a script that disenfranchises 99.9% of the masses. 

The chaos, the still blackness, the buzzing in my ears like when a 3d sensation is produced in my headphones and I can swear the bass player is over there. Hey, it's a wiggly groove on a plastic disc, bits that mimic what was heard via electronic ears. If this present immersion would stop twerking my senses would my soul experience the real reality? Or is this the purpose of reality to inundate my senses so that my soul can experience while my spirit records, god? knows and experiences thru me/us???????? All men together is god. Oooh dude, god needs an upgrade!

I see a pattern here, wonder turns into science turns into religion. Then the question do you see what I see, you must see what I see, understand what I understand the way I do, government. We write the scripts, threaten treason or hell's damnation if we don't act in the play. In my knee-jerk reaction I cock my head back, looking deep into the depths of the hazy blue and twinkly flickers and sigh, prayer.

We think we need the opinion or perspective of a rational alien who can give an unbiased fix for our dementia. Too late, our scripts have said they are neck bitters, brain eaters, viruses, flesh mangling creatures of every sort, with war and extermination agendas and the only English phrase they know is “stupid humanoid scum.” We write the scripts that makes the whole sing, we write the scripts, we write the.....................ooh, you don't know the power of the dark side. Yeah we do!

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Rivers and GRACE...

Source: Science Magazine; US Army Corp of Engineers

When ground water saturates a river basin, the risk for flooding goes up. So does the strength of Earth’s gravity in that region, ever so slightly, because of the extra mass of the underground water. By using tiny variations in gravity detected from space, researchers report online today in Nature Geoscience that they can identify basins that are primed for flooding if additional rains come—sometimes with several months' warning. As a test case, the scientists looked at the gravity signals leading up to catastrophic floods in 2011 on the Missouri River (pictured above). They used data from NASA’s Gravity Recovery and Climate Experiment (GRACE), a pair of orbiting satellites that get tugged around the Earth faster in places where gravity is slightly stronger.



Science Magazine: Gravity measurements can predict river flooding, Eric Hand
UT Austin Climate Science Research: GRACE
NASA: GRACE - Earth Missions

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BICEP2: Pro and Con...

Source: Quanta Magazine

The pro...



On March 17, a panel of four astrophysicists held a press conference at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Mass., to announce that they had discovered features in the cosmic microwave background (CMB) that are consistent with gravitational waves from the universe’s first moments. The results agreed with predictions from the decades-old theory of inflation, said panelist Chao-Lin Kuo of Stanford University, providing the first direct evidence that for an infinitesimal instant after the Big Bang, our universe expanded faster than the speed of light.



Kuo had designed the sensitive photon detectors in the telescope responsible for the breakthrough. For three years in the cold, dry atmosphere of the South Pole, the Background Imaging of Cosmic Extragalactic Polarization (BICEP2) telescope collected photons from the CMB, the 13.8-billion-year-old residue of the Big Bang. Information describing the intensity and polarization of the captured photons was transmitted by satellite to an international collaboration of 47 researchers working at various institutes. Gradually, a pattern of polarized light emerged. The researchers were initially reluctant to interpret the data as evidence for primordial gravitational waves. They labored to rule out alternative explanations for the signal, including the possibility that the pattern had been generated not by gravitational waves but by dust in the Milky Way.



The con...



In mid-March, a panel of four astrophysicists working on an experiment to probe the first moments of time held an extraordinary press conference at the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass. The scientists announced that a radio telescope located at the South Pole had discovered gravitational waves generated by the Big Bang. They posted a non-peer-reviewed paper on the Internet that proclaimed the beginning of a “new era” in cosmology.



Sharing the spotlight at the press conference were Andrei Linde and Alan Guth, two theoretical physicists who have developed seminal theories of how our universe rapidly inflated at its birth. The new results validated those theories — or so it seemed.



Stanford University and the CfA both distributed press releases calling the discovery a “smoking gun” showing that the theory of inflation is true, a phrase that appeared in international headlines about the findings. A short video of Stanford researcher Chao-Lin Kuo walking up Linde’s driveway to share the news of the discovery was viewed by millions. Smiling physicists and cosmologists nearly danced with excitement in media interviews.



Quanta Magazine:

Early-Universe Explorer Looks for Answers, (pro)
A Bold Critic of the Big Bang’s ‘Smoking Gun’, (con)
both by Peter Bryne

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Resources and Refugees...

Source and background info: Wikipedia

Refugees - whether from climate disaster, or social/political unrest - are fleeing violence and the possibility of personal extinction. That cause ultimately stems from the allocation of resources among the population. See yesterday's Malthusian Musings post.



The approximately 10 million households that have achieved the status of millionaires by net worth is 3.125% of the general population in the US. That estimate is a rebound with respect to the stock market crash of 2008 that affected the many households - not theirs - and propelled some previously in the middle class into poverty.



The crisis at the US border met by protesters at the same in California: there is no "middle class society" in Central America; no leg up as yet from poverty or bridge from that to higher classes, though it has improved. If nature abhors a vacuum, in nations with no official middle class, it is usually filled by crime. The children being callously turned away are going back to a meat grinder that will only ultimately result in their deaths. If you're born poor in such a state, you're likely to remain as such and exposed to the violence of resource allocation. Typical of this irony, it's not well known that the former richest man in the world - Carlos Slim Helú - resides there in Mexico (the crown has been recaptured by Bill Gates - U-S-A!). Trade agreements that suppress wages for the sake of corporate profits are likely to make the Carlos' of the world happy, but not many of the 99% others.



Millionaire - Billionaire - Monarchy: all a recognition of hierarchy and the need to validate it. It's usually validated by the allocation of resources at the apogee of the social pyramid construct. Like good oligarchs, it helps to control the political process and news agencies of the countries you dwell in to reinforce the mantra. Unlike Germany, that's boosted its minimum wage to 8.50 Euros ($11.50 US dollars), there is no incentive in this nation to essentially change this paradigm. Instead there are the Horatio Alger - Ayn Rand myths upon which so many have given oblation and obeisance to. Along with those myths of "pluck" and "spunk" there is the need for self-preservation at the apogee. Thus, those at the top of the pyramid have no incentive to change the structure of how they got there. It would de-legitimize the construct they've worked so hard to preserve/conserve that has passed down from forebears to inheritors.



The other myths that must be fostered are "a constitutional crisis"; "government overreach"; a "need to return to principles" (whatever they are). Along with it, helps to insert in the public narrative pseudoscience like "climate change denial"; "intelligent design" to obfuscate and eliminate the tools a populace can use to question those in authority.



Refugees - whether from climate disaster, or social/political unrest - are fleeing violence and the possibility of personal extinction, may just be for many a cynical Calculus, the cost of doing business; the "noise" in the signal of ever-increasing profitability. Noise ignored, only increases in intensity and ultimately dampens the signal desired: a zero-sum deconstruction.

PBS: Life Beyond Earth: Drake Equation Calculator
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Malthusian Musings...

Figure 1: Changes in a population of Paramecium over a six day period
Each individual in the population divides once per day. Source: Nature link below.

The link to Wolfram leads to the differential equation for population growth.

N(t) = N0ert

N0 = initial number.

r = Malthusian parameter, meaning population growth rate.

t = time



So, if you crank through the math a little:



Global

N0 = 7,176,768,000 (CENSUS.gov is scrolling pretty fast, so this is an estimate)

r = 0.012

t = 2042 - 2014 = 28



N(t) = 10,042,731,534.4143



US

N0 = 318,373,944 (again, an estimate)

r = 0.012

t = 2042 - 2014 = 28



N(t) = 445,513,084.32217



More humans; dwindling resources (bees, food, water, fossil fuel); diminished ozone protection; greenhouse gases; political unrest and conflicts; congressional obfuscation; "blame-the-other," homophobia, racism, sexism, xenophobia; "open carry"; doomsday preppers; tactical nukes in theater; pseudoscience; socially-engineered stupidity in science; same volume of planet under our feet as it was when there was literally "cattle on a thousand hills" (and, way before agribusiness or GMOs):

What could possibly go wrong?


Tomorrow: Resources and Refugees



Nature: How Populations Grow

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        Black Pulp Heroes are a rare breed... but they are 

       starting to be produce regardless of the lack of

       them... Oh, I know a few of them are out there

       already.

         Yet, the more the merrier.

          All of this and more is featured in Aura, The Art of

           Winston Blakely.

            September is the release month for the book in all its

           glory.

           

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Resistance and Quantum Physics...

Figure 1: As an electron (dark blue) in a metal is deflected by an impurity atom (orange), further scattering of the electron is caused by its fluctuating interactions with the surrounding electrons (light blue). These fluctuations add an intrinsically dynamical contribution to the resistivity of the metal. Credit: see [+] below

A new model shows that quantum fluctuations make a significant contribution to a metal’s low-temperature resistance.



Electrical resistance in metals like copper and silver mainly comes from the scattering of electrons by vibrations in the crystal lattice (phonons). These vibrations die away at low temperatures, which explains why metals become less resistive when you cool them. But a small “residual resistivity” persists at low temperatures because electrons also scatter from impurities, such as a vacancy or an atom of a different species, which are always present in any real metal. So far, the residual resistivity was thought to only depend on the interaction between each electron and the impurities, but a new theory from Vladimir Nazarov and Yia-Chung Chang at the Academia Sinica, Taiwan, and Giovanni Vignale at the University of Missouri in Columbia shows that dynamical interactions between electrons—a many-body effect—also make a distinct contribution in the presence of impurities [1]. Their theory provides the first quantitative description, from first principles, of the resistivity of simple metals at low temperatures. As an example, they show that many-electron effects can explain the measured value of the residual resistivity of aluminum.



One of the oldest theories in condensed-matter physics is that of the conduction of an electrical current through a metal. In Paul Drude’s 1900 classical perspective [2], electrons in a metal are constantly moving in all directions, rather like molecules in a gas, but since their net momentum is zero, so is the current. Applying a voltage between the ends of the conductor creates an electric field that causes the electrons to veer slightly towards the positive end, producing a net current. From time to time, collisions once again randomize the electrons’ directions of motion. The frequency of such collisions determines the metal’s resistance. [+]



In a high-resolution photoemission study of a Mo(110) surface state various contributions to the measured width and energy of the quasiparticle peak are investigated. Electron-phonon coupling, electron-electron interactions and scattering from defects are all identified mechanisms responsible for the finite lifetime of a valence photo-hole. The electron-phonon induced mass enhancement and rapid change of the photo-hole lifetime near the Fermi level are observed for the first time. [~]

+ American Physical Society Viewpoint:
Quantum Jostling Proves Diverting for Electrons in a Metal
Rex Godby, Department of Physics, University of York, York YO10 5DD, United Kingdom
~ Physics arXiv:
Many-body Effects in Angle-resolved Photoemission: Quasiparticle Energy and Lifetime of a Mo(110) Surface State
T. Valla, A. V. Fedorov, P. D. Johnson, S. L. Hulbert

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Modeling Stars in 3-D...

Volume rendering of the entropy of a differentially rotating and highly magnetized progenitor to a supernova in a full 3-D. Red colors indicate high entropy (hot) material while blue represents low entropy (cold) material. Strongly magnetized material is continuously launched from the surface of the proto-neutron star in the center but gets severely distorted such that, instead of a clean jet observed in the ultra-strong magnetic field case, two giant polar lobes are formed. The box size for the visualization is 2000km cubed.

Credit: Philipp Moesta, TAPIR, California Institute of Technology


[The following is Part eight in a series of stories that highlight recent discoveries enabled by the Stampede supercomputer. In parts one, two, three, four, five, six and seven, learn how the system is helping to advance research throughout science and engineering.]



Using the National Science Foundation-supported Stampede supercomputer, Philipp Moesta and Christian D. Ott from the California Institute of Technology succeeded in performing the first 3-D simulations of a collapsing star that takes into account the influence of general relativity and magnetohydrodynamics--the interplay of electrically conducting fluids like plasmas and powerful magnetic fields. The death of these collapsing stars leads to energetic, jet-driven supernova explosions.



Their findings show that the simulations behave very differently in full, unconstrained 3-D compared to the same model simulated with the assumption that stars are sperically symmetrical.



National Science Foundation: Everything is Better in 3-D

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SI Facelift...

NIST
Citation: Phys. Today 67, 7, 35 (2014); http://dx.doi.org/10.1063/PT.3.2448

The universally accepted method of expressing physical measurements for world commerce, industry, and science is about to get a facelift, thanks to our improved knowledge of fundamental constants.



Although the present International System of Units (SI, from the French Système International d’Unités) was officially established in 1960, its origin goes back to the creation of the metric system during the French Revolution. Following an idea proposed a century earlier by John Wilkins, 1 the new system of weights and measures took as its starting point a single universal measure—the meter—and used it to define length, volume, and mass. The meter came from a perceived constant of nature: one ten-millionth of the distance along Earth’s meridian through Paris from the North Pole to the equator. 2 Definitions for the units of volume and mass followed, with the liter being 0.001 m 3 and the kilogram the mass of 1 liter of distilled water at 4 °C. Subsequently, in 1799, two platinum artifact standards for length and mass based on those definitions were deposited in the Archives de la République in Paris. In the words of the Marquis de Condorcet, a new system of measurement “for all time, for all people” was born.



The SI is a living, evolving system, changing as new knowledge and measurement needs arise, albeit sometimes slowly when measured against the rapid pace of scientific progress.



The new SI will also have seven base quantities: frequency, velocity, action, electric charge, heat capacity, amount of substance, and luminous intensity. The specific reference quantities will be the exact values of a set of defining constants: the ground-state hyperfine splitting of the cesium-133 atom Δ ν( 133Cs) hfs, c, h, e, k, the Avogadro constant N A, and the luminous efficacy K cd. However, to provide continuity and ease of transition, their values will be expressed in terms of the present SI units instead of in potentially confusing new base units.



Physics Today: A more fundamental International System of Units
David B. Newell

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The ceremony included a bit of comedy, but there was no denying the significance: For the first time in its history, the Navy promoted a woman on Tuesday to become a four-star admiral.

Surrounded by friends, family and peers, Adm. Michelle J. Howard was promoted to her new rank at the Women in Military Service for America Memorial at Arlington National Cemetery. She’ll take over as the vice chief of naval operations, the No. 2 officer in the service. She is not only the first woman to hold the job, but the first African-American.

It’s the latest achievement for Howard, who previously was the first African-American woman to serve as a three-star officer in the U.S. military and command a U.S. Navy ship. Navy Secretary Ray Mabus said her promotion is a “representation of how far we have come, and how far she has helped bring us.”

“She is also a great example of how much we as a nation and a Navy lose if we put artificial barriers in,” Mabus told a crowd of about 150 people. “If we don’t judge people based on their ability, based on their capability. I hope I have always been passionate about that, but I know the intensity has increased since I am the father of three daughters, and I refuse to believe that there are any ceilings for them, glass or otherwise. That they can get to wherever their abilities can take them. And with that, they and countless others in the Navy now have a wonderful role model in Michelle Howard.”

With that said, Mabus added that “there is no news here today,” because the Navy picked the best officer, Howard, for her new job.

Howard is perhaps best known for leading Task Force 151, which oversaw counter-piracy operations in the Gulf of Aden. After Somali pirates attacked the cargo ship MV Maersk Alabama and captured its top officer, Capt. Richard Phillips, in April 2009, she devised a plan with others to get him back, dispatching the USS Bainbridge, a destroyer, to help. Navy SEAL snipers eventually opened fire on a small lifeboat carrying Phillips and three pirates, killing the bandits and freeing him.

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