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Cosmic Mystery...

Posted by Reginald L. Goodwin on January 18, 2017 at 2:38pm
Figure 1: Both the LUX and PandaX-II experiments look for dark matter particles (Chi-Chi) by sensing their interaction with xenon atoms. The detector in each experiment consists of a large tank of ultrapure liquid xenon (dark purple) topped with xenon gas (light purple). An interaction produces two light signals, one from photons, S1, and another, S2, from electrons when they drift into the gas. The signals are detected by photomultiplier tubes at the top and bottom of the tank (yellow cylinders). [Credit: APS/Carin Cain]


Topics: Astronomy, Astrophysics, Cosmology, Dark Matter


Over 80 years ago astronomers and astrophysicists began to inventory the amount of matter in the Universe. In doing so, they stumbled into an incredible discovery: the motion of stars within galaxies, and of galaxies within galaxy clusters, could not be explained by the gravitational tug of visible matter alone [1]. So to rectify the situation, they suggested the presence of a large amount of invisible, or “dark,” matter. We now know that dark matter makes up 84% of the matter in the Universe [2], but its composition—the type of particle or particles it’s made from—remains a mystery. Researchers have pursued a myriad of theoretical candidates, but none of these “suspects” have been apprehended. The lack of detection has helped better define the parameters, such as masses and interaction strengths, that could characterize the particles. For the most compelling dark matter candidate, WIMPs, the viable parameter space has recently become smaller with the announcement in September 2016 by the PandaX-II Collaboration [3] and now by the Large Underground Xenon (LUX) Collaboration [4] that a search for the particles has come up empty.

Since physicists don’t know what dark matter is, they need a diverse portfolio of instruments and approaches to detect it. One technique is to try to make dark matter in an accelerator, such as the Large Hadron Collider at CERN, and then to look for its decay products with a particle detector. A second technique is to use instruments such as the Fermi Gamma-ray Space Telescope to observe dark matter interactions in and beyond our Galaxy. This approach is called “indirect detection” because what the telescope actually observes is the particles produced by a collision between dark matter particles. In the same way that forensic scientists rely on physical evidence to reverse-engineer a crime with no witnesses, scientists use the aftermath of these collisions to reconstruct the identities of the initial dark matter particles.

The third technique, and the one used in both the LUX and PandaX-II experiments, is known as “direct detection.” Here, a detector is constructed on Earth with a massive target to increase the odds of an interaction with the dark matter that exists in our Galaxy. In the case of LUX and PandaX-II, the dark matter particles leave behind traces of light that can be detected with sophisticated sensors. This is akin to having placed cameras at the scene of a crime, capturing the culprit in the act.

The heart of both LUX, located in South Dakota in the US, and PandaX-II, situated in Sichuan, China, is a time-projection chamber. This consists of a large tank of ultrapure liquid xenon—250 kg at LUX and 500 kg at PandaX-II—topped with xenon gas (Fig. 1). A particle (dark matter or ordinary matter) that enters the chamber and interacts with a xenon atom in the liquid generates photons (by scintillation) and electrons (by ionization). The photons produce a signal, S1, which is read by photomultiplier tubes located at the top and bottom of the tank. The electrons are instead coaxed into the gaseous portion of the detector by an electric field where they induce a second round of scintillation and a signal S2. The pattern of S1 and S2 signals is different when the xenon interacts with a dark matter particle than with an ordinary particle, which is what allows scientists to distinguish between two such events. To reduce the background signal from ordinary particles, both LUX and PandaX-II are buried underground to provide protection from cosmic rays. In addition, the use of ultrapure materials in the construction of the experiment cuts the background contributed by radioactive emissions.

APS Viewpoint: Dark Matter Still at Large
Jodi A. Cooley, Department of Physics, Southern Methodist University, 3215 Daniel Ave., Dallas, TX 75205, USA
January 11, 2017• Physics 10, 3

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Euler's Method...

Posted by Reginald L. Goodwin on January 17, 2017 at 9:30am
From Notes on Diffy Qs: Differential Equations for Engineers, by Jirí Lebl

"What if we want to find the value of the solution at some particular x? Or perhaps we want to produce a graph of the solution to inspect the behavior. In this section we will learn about the basics of numerical approximation of solutions.

The simplest method for approximating a solution is Euler’s method. It works as follows: We take x0 and compute the slope k = f (x0; y0). The slope is the change in y per unit change in x. We follow the line for an interval of length h on the x axis. Hence if y = y0 at x0, then we will say that y1 (the approximate value of y at x1 = x0 + h) will be y1 = y0 + hk. Rinse, repeat! That is, compute x2 and y2 using x1 and y1." See Notes on Diffy Qs above (under graphic)


 Topics: Differential Equations, Diversity in Science, Mathematics, Women in Science

Okay, this is the LAST time I'll talk about Hidden Figures (although I did order the book).

Not to spoil it for you, but Dr. Katherine Johnson (played by Taraji P. Henson) mentioned an "old method" of mathematics. What both the actress and NASA scientist referred to is something you're taught usually sophomore year in a STEM major. Euler's Method is named after Leonhard Euler, and it's used to numerically approximate differential equations, something in the movie and the embed below alludes to is now done by what we now know as computers (the laptop kind, not female mathematicians).

It is important to understand the steps, derivation and mathematics behind computer calculation. How do you KNOW it's right? I'm often challenged as to "when I ever use Calculus" at work. Most often they're right, I don't. There's a software package designed with the equations embed within them to literally SPIT out an answer. The program doesn't have imagination nor does it visualize an expected end result. "The answer" is the end of a calculation without any notion of its consequences if incorrect.

Part of its practicality is essentially how the study of mathematics and physics organizes one's thinking. I use systematic approaches to solving just about any problem in life. However in Hidden Figures, it was initially the NASA scientists and eventually Dr. Johnson knowing the mathematics and relying on human insight and intuition that averted catastrophe, not that it doesn't happen when launching humans on the top of essentially systematic staged bombs to achieve Earth orbit.

The old riddle "which came first: the chicken or the egg?" can easily be answered with regards to computers and humans. The Singularity will have a ways yet.

François Arago said of him (Euler) "He calculated just as men breathe, as eagles sustain themselves in the air" (Beckmann 1971, p. 143; Boyer 1968, p. 482). [1]

In a testament to Euler's proficiency in all branches of mathematics, the great French mathematician and celestial mechanic Laplace told his students, "Liesez Euler, Liesez Euler, c'est notre maître à tous" ("Read Euler, read Euler, he is our master in everything" (Beckmann 1971, p. 153). [2]

1, 2: Scienceworld.Wolfram.com: Euler
LA Times:
Meet the ‘Hidden Figures’ mathematician who helped send Americans into space, Amina Khan

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Squeezing Below The Quantum Limit...

Posted by Reginald L. Goodwin on January 16, 2017 at 10:37am




NIST researchers applied a special form of microwave light to cool a microscopic aluminum drum to an energy level below the generally accepted limit, to just one fifth of a single quantum of energy. Having a diameter of 20 micrometers and a thickness of 100 nanometers, the drum beat 10 million times per second while its range of motion fell to nearly zero.

Credit: Teufel/NIST

Topics: Metamaterials, Nanotechnology, Quantum Computer, Quantum Mechanics


Physicists at the National Institute of Standards and Technology (NIST) have cooled a mechanical object to a temperature lower than previously thought possible, below the so-called “quantum limit.”

The new NIST theory and experiments, described in the Jan. 12, 2017, issue of Nature, showed that a microscopic mechanical drum—a vibrating aluminum membrane—could be cooled to less than one-fifth of a single quantum, or packet of energy, lower than ordinarily predicted by quantum physics. The new technique theoretically could be used to cool objects to absolute zero, the temperature at which matter is devoid of nearly all energy and motion, NIST scientists said.

“The colder you can get the drum, the better it is for any application,” said NIST physicist John Teufel, who led the experiment. “Sensors would become more sensitive. You can store information longer. If you were using it in a quantum computer, then you would compute without distortion, and you would actually get the answer you want.”


 NIST Physicists ‘Squeeze’ Light to Cool Microscopic Drum Below Quantum Limit
Laura Ost
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I, Nerd...

Posted by Reginald L. Goodwin on January 13, 2017 at 7:00am
Image Source: see "most intimidating Captain" below, or StarTrek.com


Topics: Commentary, Diversity in Science, Science Fiction, Star Trek, STEM


I am a nerd. Those of us of African descent have taken the name "blerds."

During the 70's, being a nerd of color wasn't a family outing in the park. I recall getting bullied...a lot. The fact that I: never ate nor liked the smell of chitterlings; watched Star Trek, Mutual of Omaha's Wild Kingdom and The Undersea World of Jacques Cousteau didn't help much either. A distinct memory of my nose bloodied from getting shoved in my locker after 9th grade English class for reading a poem - a haiku (that WAS the assignment) and getting the F-bomb epithet while my assailants sprinted down the hall. I noted when as an undergraduate almost the entire school karate team - led by my Calculus instructor - consisted entirely of STEM majors, with the exception of one in Communications. Nerds tend to know from experience defensive skills are a PLUS.

I noticed Physics Today and its related media Inside Science commented on the sitcom The Big Bang Theory. I've watched a few episodes, though with the exception of passing interest I have understandably never been a big fan. I can recall seeing a scene (a "scene" mind you) with Dr. Neil deGrasse Tyson on YouTube. I recall seeing an episode (maybe two?) with actress Regina King as an HR rep that had to haul Sheldon and company into her office to "set them straight." She's listed as officially appearing in four.

The big nerd show of my day was Star Trek, and The Bang gives a lot of hat tips to it quite often in their dialogue. It was the blend of science and swashbuckling; you could study the cosmos faster-than-light (defying all laws of physics), do a flying sidekick (Kirk) or a Vulcan neck pinch (Spock). Note to Sheldon: kick, yes; pinch, no.

I specifically in many ways was enamored with Nichelle Nichols/Lieutenant Uhura. It was moving that Dr. Martin Luther King talked her into staying after her first season as a role model. I'm grateful that she stayed, because without the image others might not have tried majoring in STEM like Dr. Mae Jemison, Dr. Tyson, Dr. Ronald E. McNair (deceased from the Challenger Disaster).

Even in my fandom, I have listed a few of my observations and critiques (this starts with TOS and its recent variants):
  • Uhura was technically third in command of the Enterprise, though I don't recall an episode where she took "the comm" (command chair). She technically outranked Scottie who took command in the Captain's absence on several occasions.
  • With the exception of a vampire salt monster (The Man Trap) masquerading as a black male and speaking Swahili; her forced kiss with Captain Kirk (Plato's Stepchildren - not played then in racist southern markets) she never had a story arc with a love interest.
  • Dr. Richard Daystrom (William Marshall), a genius that apparently won the Nobel Prize in I'd assume Computer Science (as yet not seen up to now - we get Peace Prizes mostly) and something called the Zee-Magnees Prize in 2243 invented the talking personal computers with Majel Barrett's voice and attitude. He of course also conveniently went mad. He would become the archetype for Miles Dyson (Joe Morton) in Terminator 2: Judgment Day, the twist is he didn't go mad, his creation did when it reached the Singularity, and realized humans are generally pricks.
  • With Captain's Kirk (TOS), Picard (TNG), Janeway (VOY), and Archer (ENT) their respective series STARTED with them at the rank of Captain. Their previous experiences were referred to in passing commentary, and their records deemed impeccable and impressive.
  • Benjamin Sisko started Deep Space 9 at the rank of Commander, though he eventually promoted into Captain. He also started with "an attitude," seeing Picard was the reason his wife died in the Borg battle at Wolf 359. He also punched Q (not mad at him for that), but it did play into the stereotype of being hotheaded. He was also a reluctant single dad (see "attitude"). He made "most intimidating Captain" in a Trek poll.
  • In Star Trek: Discovery Michelle Yeoh, fresh off "Crouching Tiger, Hidden Dragon" will play a starfleet Captain. Following the Sisko formula, the leader of the Starship Discovery Sonequa Martin-Green will start her screen life as a Lieutenant Commander (and from Sisko level, demoted), so it seems a sister STILL has to work twice as hard to get ahead in the Utopian 23rd Century.

Don't get me wrong: I'm not saying Star Trek hasn't done a lot of things RIGHT. The old Motorola StarTek was a knockoff of the Trek communicator; comm badges in TNG became the model for Bluetooth devices everyone had in their ears (talking to themselves) until we piped it through our radios. Heck, we even have the makings with phone apps of a Universal Translator; automatic doors at the mall started out on Trek with two guys on either side of William Shatner opening and closing the door on queue before optical electronics (and there were in all variants bloopers). It's just that scripts are usually written in a vacuum, usually with a team of people you know, and dependent on that team's exposure to diversity and other cultures well, see the above bullets.

Since the 1960 presidential debates between John F. Kennedy and Richard M. Nixon, images have mattered. Like the Internet and social media, television changes our brains and perceptions of what is real and what is frankly true. Though I was not on the planet, many who watched the presidential debates thought the cooler, younger, non-sweaty and more photogenic Kennedy won the debate. For the "old school" radio listeners, Nixon won it. Technology has been skewing our perceptions ever since.

Part of the goal of working in STEM at any level is imagining yourself in the role doing it. Taraji P. Henson - I talked about her last week at the debut of Hidden Figures (GO see it) said reading the script for the movie "hurt her" because she would have liked to know of these women when she was growing up. Images matter to young people that have a visual media thrown at them now 24/7 through flat screens, laptops and mobile devices; they are "programmed" quite subtly in what is proper for them to aspire to. Trivia: Ms. Henson majored in Electrical Engineering at my Alma Mater before transferring to Howard and majoring in Drama. The rest as they say, is history. Maybe she has a valid point. For that, young people all need actors that look like themselves so they can start thinking it is possible. I hope, like her to facilitate that.

In the meantime:

Je suis noir (I am black).

I am nerd.

I will (as long as ambulatory) blog.
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Electron Puddle...

Posted by Reginald L. Goodwin on January 12, 2017 at 7:10am
In a new study, Argonne scientists have discovered a way to confine the behavior of electrons by using extremely high magnetic fields. (Image by Argonne National Laboratory.)


Topics: Electromagnetism, Materials Science


Olympic figure skaters and electrons have a lot in common. In figure skating competitions, the "free skate" segment gives the skater the flexibility to travel in whichever pattern he or she chooses around the rink. Similarly, in metals, electrons in outer orbitals can wander fairly freely.

However, when the magnetic field is increased dramatically, researchers have found that the motion of these electrons becomes much more tightly confined. Their behavior looks like figure skaters completing compulsory tight spins and jumps.

In a new study from the U.S. Department of Energy's (DOE's) Argonne National Laboratory, researchers used extremely high magnetic fields — equivalent to those found in the center of neutron stars — to alter electronic behavior. By observing the change in the behavior of these electrons, scientists may be able to gain an enriched understanding of material behavior.

"The rules of the game are changed when we apply a magnetic field of this intensity," said Argonne materials scientist Anand Bhattacharya, who led the research. "The nature of this new state that we see has been debated theoretically for over half a century, but experiments to measure its properties have been hard to come by."

Argonne National Laboratory:
Electrons "puddle" under high magnetic fields, study reveals, Jared Sagoff

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Fusion Breeding...

Posted by Reginald L. Goodwin on January 11, 2017 at 8:35pm
Image Source: Binus University Research Interest Group


Topics: Alternative Energy, Nuclear Fusion, Nuclear Physics, Nuclear Power

 Abstract

This article is an editorial, which makes the case that fusion breeding (that is using fusion neutrons to breed nuclear fuel for use in conventional nuclear reactors) is the best objective for the fusion program. To make the case, it reviews a great deal of plasma physics and fusion data. Fusion breeding could potentially play a key role in delivering large-scale sustainable carbon-free commercial power by mid-century. There is almost no chance that pure fusion can do that. The leading magnetic fusion concept, the tokamak, is subject to well-known constraints, which we have called conservative design rules, and review in this paper. These constraints will very likely prevent tokamaks from ever delivering economical pure fusion. Inertial fusion, in pure fusion mode, may ultimately be able to deliver commercial power, but the failure to date of the leading inertial fusion experiment, the National Ignition Campaign, shows that there are still large gaps in our understanding of laser fusion. Fusion breeding, based on either magnetic fusion or inertial fusion, greatly relaxes the requirements on the fusion reactor. It is also a much better fit to today’s and tomorrow’s nuclear infrastructure than is its competitor, fission breeding. This article also shows that the proposed fusion and fission infrastructure, ‘The Energy Park’, reviewed here, is sustainable, economically and environmentally sound, and poses little or no proliferation risk.

Introduction

The fusion program, both short term and long term, is in trouble, certainly in the United States, and likely worldwide. In addition to large cost overruns and failures to meet milestones, surely another reason is that pure fusion has almost no chance of meeting energy requirements on a time scale that anyone alive today can relate to. Hence the assertion of this article is that fusion breeding of conventional nuclear fuel is a likely way out of fusion’s current and future difficulties. Fusion breeding substantially reduces the requirements on the fusion reactor. It significantly reduces the necessary Q (fusion power divided by input power), wall loading, and availability fraction. The capital cost of a reactor, estimated based on ITER’s capital cost, is affordable for fusion breeding, but definitely is not for pure fusion. It is likely that fusion breeding can produce fuel at a reasonable cost by mid century. The entire fusion and fission infrastructure would be sustainable, economical, environmentally sound, and have little or no proliferation risk. This article’s mission then, is to hopefully convince a much larger portion of the fusion establishment to make this case. At the very least it hopes to broaden the discussion in the fusion community from where we are now, where one prestigious review committee after another insists that every existing project is absolutely vital, nothing can be changed; except give us more $$$. The inevitable result of this process is that one fusion project after another gets knocked off.



 RD Springer: Fusion Breeding for Mid-Century Sustainable Power, Wallace Manheimer

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Brexit and Exodus...

Posted by Reginald L. Goodwin on January 10, 2017 at 9:30am
Image Source: Wiki Gender

Topics: Existentialism, Politics, Science, Research

A survey of more than 1,000 UK-based university staff suggests that the country’s vote to leave the European Union could drive an academic exodus.

Forty-two per cent of lecturers and professors surveyed say they are more likely to consider leaving the UK higher-education sector as a result of the referendum outcome. The proportion was even greater (76%) among the non-UK EU citizens in the survey, commissioned by the University and College Union, which represents tens of thousands of academics and is based in London.

Many individual foreign researchers have said they feel less welcome in Britain after the Brexit vote, or that they now see better opportunities abroad. But the latest poll is one of the clearest indications of the widespread nature of this feeling in UK academia.


 Scientific American: Brexit May Spark British Brain Drain, Daniel Cressey
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Lucy and Psyche...

Posted by Reginald L. Goodwin on January 9, 2017 at 2:50pm
(Left) An artist’s conception of the Lucy spacecraft flying by the Trojan Eurybates – one of the six diverse and scientifically important Trojans to be studied. Trojans are fossils of planet formation and so will supply important clues to the earliest history of the solar system. (Right) Psyche, the first mission to the metal world 16 Psyche will map features, structure, composition, and magnetic field, and examine a landscape unlike anything explored before. Psyche will teach us about the hidden cores of the Earth, Mars, Mercury and Venus.
(Photo: SwRI and SSL/Peter Rubin)


Topics: Asteroids, NASA, Planetary Science, Space Exploration


NASA will embark on two missions it says could unlock secrets to how our solar system was formed.

The Lucy and Psyche missions — both robotic, unmanned endeavors controlled from Earth — will take us back to the time 10 million years after the sun was born.

Lucy will visit the Trojan asteroids of Jupiter when it launches in October 2021. Scientists suspect the asteroids, currently caught in the largest planet's 12-year orbit around the sun, may have existed in the beginnings of the solar system and before Jupiter's orbit.

Lucy's principal investigator Harold F. Levison claims the mission will yield other-worldly insight into our universe.

"Because the Trojans are remnants of the primordial material that formed the outer planets, they hold vital clues to deciphering the history of the solar system," he explained. "Lucy, like the human fossil for which it is named, will revolutionize the understanding of our origins."

But don't wait up, Lucy's first stop won't come until 2025 when it arrives at a main belt asteroid. It will examine the Trojans from 2027 to 2033.

USA Today: NASA asteroid missions to discover secrets of the universe, Sean Rossman

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blerdsunite

Posted by Tywon Terrell on January 9, 2017 at 2:14pm

I guess life does come full circle, I haven't been on here in a long time. I have started tweeting up under the name @blerdsunite and I will be launching a group on FB soon followed by the website. On twitter what i'm basically doing is highlighting  a lot of different black artist, authors, illustrators, graphic designers, musicians, scientists etc. Instead of focusing on the standard Blerd topics which cover a lot of the mainstream I try to include all, but "us" in particular. Check me out, i'm finally back!!! 

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Hidden Figures...

Posted by Reginald L. Goodwin on January 6, 2017 at 12:47pm
Image Source: Madame Noire
Taraji P. Henson (Katherine Johnson), Janelle Monae (Mary Jackson) and Octavia Spencer (Dorothy Vaughn)


Topics: Diversity, Diversity in Science, NASA, STEM, Women in Science


Katherine Johnson, Dorothy Vaughn, and Mary Jackson are members of Alpha Kappa Alpha Sorority, Inc. The Iota Alpha Omega chapter have rented out the Poughkeepsie Galleria as a fundraiser for the sorority and general positive exposure to the public for the organization in general and African Americans in STEM in particular. I was proud to do an electronics STEM fair at the Children's Home of Poughkeepsie in 2014. I will proudly without as much effort support this tonight.

When you think of NASA and Black women, Mae Jemison no doubt comes to mind. But long before Jemison became the first African American woman to travel in space in 1992, there were three women of color already making history at the National Aeronautics and Space Administration, and now their story will finally be told in the upcoming theatrical release, Hidden Figures.

The movie, which stars Taraji P. Henson, Octavia Spencer, and Janelle Monae, tells the story of Katherine Johnson, Dorothy Vaughn, and Mary Jackson —”brilliant African-American women working at NASA, who served as the brains behind one of the greatest operations in history: the launch of astronaut John Glenn into orbit, a stunning achievement that restored the nation’s confidence, turned around the Space Race, and galvanized the world,” a press release relayed.

Madame Noire:
First Look At Hidden Figures, The Untold Story Of NASA’s Black Female Leaders
Brande Victorian

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NDR in Single Atoms...

Posted by Reginald L. Goodwin on January 5, 2017 at 7:30am
Dark center. In these scanning tunneling microscope images of current flow through a single atom on a silicon surface, the dimming of the center shows current decreasing as the voltage increases (from right to left). The halo shows that current flowing around the atom behaves normally. [Credit: M. Rashidi et al./Univ. of Alberta]


Topics: Electrical Engineering, Particle Physics, Quantum Mechanics, Scanning Tunneling Microscopy


Negative differential resistance (NDR) refers to current decreasing as voltage increases, contrary to a normal resistor. The phenomenon is useful in electronics, and now a research team has demonstrated a reliable form of single-atom NDR and has explained in detail how it works. To verify their model, the team used a scanning tunneling microscope in a new way—they measured the time it takes for electrons to hop onto a single atom and showed that this time is critical for the NDR effect. The work opens the door to integration of NDR into microelectronic devices.

NDR was first observed in the tunnel diode 50 years ago [1]. Tunnel diodes are used in switching devices, oscillators, and other applications. However, it has proven difficult to incorporate them into integrated circuits, limiting their wider use in microelectronics. Researchers have found cases of nanoscale NDR, but they have been either unreliable or hard to control.

Robert Wolkow of the University of Alberta in Edmonton, Canada, and his colleagues created a robust, single-atom NDR device by baking a silicon wafer to remove surface-attached oxygen and then immersing it briefly in atomic hydrogen at very low pressure. Hydrogen atoms bonded to almost every surface silicon atom, leaving only a few atoms exposed. These atoms provided so-called dangling bonds, each of which hosted two electrons, one with higher energy than the other.

APS Focus: Negative Resistance with a Single Atom, David Lindley

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Quantum Particles in 1D...

Posted by Reginald L. Goodwin on January 4, 2017 at 7:39am
Figure 1: Castro-Alvaredo et al. [1] and Bertini et al. [2] used a hydrodynamics approach to describe interacting quantum particles in 1D (bottom). The approach takes a zoomed-out picture of the particles (middle), viewing it on a length scale ll that is much longer than the average distance dd between particles. In this way, the particles appear as a continuous medium, like a fluid. A description of the system on a very long length scale LL can then be calculated, such as how its mass density varies in space (top) and how this quantity evolves in time.


Topics: Particle Physics, Quantum Mechanics, Theoretical Physics


Whether attempting to crack the mystery of high-temperature superconductors or describe a cloud of ultracold atoms, theorists face a similar question: What is the best way to model the behavior of many interacting quantum particles? Most models for such systems are extremely hard to solve analytically, or even simulate on a classical computer. In this context, models for one-dimensional (1D) systems are special because they have mathematical properties that often permit an exact mathematical solution. But even these solvable models aren’t ideal for describing real experiments, particularly those involving many out-of-thermal-equilibrium particles, like a cloud of atoms being released from a trap. A way to realize this description for a large class of widely used 1D models has now been reported in two independent papers, one by Olalla Castro-Alvaredo from the University of London, UK [1], and colleagues and the other by Bruno Bertini from the International School for Advanced Studies in Trieste, Italy, and colleagues [2].

A beautiful method of realizing quantum particles in a 1D setting is to confine ultracold atoms in an elongated (cigar-shaped) trap [3]. If the atoms are bosons, this system can be described by the 1D “delta Bose gas.” In this paradigmatic model, particles move solely along a line. They also mutually repel each other, but only when they are at exactly the same position, hence the “delta” in the model’s name. In the absence of an external trapping potential, this model is exactly solvable in the sense that the particles’ energy spectrum can be calculated [4].

APS Viewpoint: A More Efficient Way to Describe Interacting Quantum Particles in 1D
Jérôme Dubail, Institut Jean Lamour, CNRS and Université de Lorraine, Faculté des Sciences, Boulevard des Aiguillettes F-54506 Vandoeuvre-lès-Nancy, France
December 27, 2016• Physics 9, 153

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Flight of the Falcon...

Posted by Reginald L. Goodwin on January 3, 2017 at 8:40am
A SpaceX Falcon 9 rocket blasts off from Cape Canaveral, Florida April 8, 2016 in this handout photo provided by SpaceX. REUTERS/SpaceX/Handout via Reuters


Topics: Mars, NASA, Science Fiction, Space Exploration, Spaceflight


I invite you to watch the Mars series on National Geographic (trailer below). It appeals to me because all science fiction is speculative, but the series does a superb job of juxtaposition between what is being planned and discussed now and projecting how it might be carried out in the future. Part of our journey to other worlds as a space faring species will be in stuttered, baby steps until the profoundly difficult becomes routine.

Elon Musk’s SpaceX plans to resume flying rockets next week following an investigation into why one of them burst into flames on a launch pad four months ago, the company said on Monday.

In a statement, SpaceX said it expected to launch a Falcon 9 rocket from California's Vandenberg Air Force Base on Jan. 8 to put 10 satellites into orbit for Iridium Communications Inc.

SpaceX had suspended flights after the same model rocket went up in a blaze on Sept. 1 as it was being fueled for a routine pre-launch test in Florida.

The explosion at Cape Canaveral Air Force Station in Florida destroyed the $62 million rocket and a $200 million communications satellite.

Space X, owned and operated by Tesla Motors Inc. Chief Executive Officer Musk, has a backlog of more than 70 missions for NASA and commercial customers, worth more than $10 billion.

The company statement said that accident investigators concluded that a canister of helium inside the rocket’s upper-stage oxygen tank had exploded.

In the short term, SpaceX plans to revamp its fueling procedures so that the super-cold liquid oxygen will not build up between the helium tank’s liner and its outer covering, it added.

SpaceX said accumulation of oxygen in a void or buckle in the liner most likely led to the explosion.

Reuters Science: SpaceX aims for Jan. 8 return to flight with Falcon rocket
Reporting by Irene Klotz, Editing by W Simon

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Nitrogen-Doped Carbon...

Posted by Reginald L. Goodwin on January 2, 2017 at 7:12am


Phenol-urea-formaldehyde (PUF) organic foam were used as precusors for the new monolithic nitrogen-containing microporous cellular activated carbons production. Carbonization and CO2 activation were used to prepare this novel monolithic nitrogen-containing activated carbon foam with both interconnected macroporous and micro/meso- porosity structures from the developed PUF organic foam. The macroporosity corresponded to the connected network of cells with diameters ranging from 100 to 600 µm, and the pinholes in the cell walls had diameters ranging from 1 to 2 µm. The micro/mesoporosity is located at the inner surface of the cells. They can be used just like the classic activated carbon as an adsorbent, catalyst support, energy storage and biological material in various industries, but higher adsorption kinetics. Credit: World Scientific Publishing

Topics: Biology, Biochemistry, Biotechnology, Research


Researchers have developed monolithic, nitrogen-containing, microporous, cellular-activated carbon from phenol-urea-formaldehyde (PUF) organic foam for CO2 and H2 adsorption. The macroporosity corresponded to the connected network of cells with diameters ranging from 100 to 600 μm, and the pinholes in the cell walls had diameters ranging from 1 to 2 μm. The micro/mesoporosity is located at the inner surface of the cells.

Phys.org: Researchers produced nitrogen-doped, cellular-structure-activated carbon


More information: Weigang Zhao et al, Preparation and Characterization of Nitrogen-Containing Cellular Activated Carbon for CO and H Adsorption, Nano (2016). DOI: 10.1142/S1793292017500072
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Seeking Submissions for New Science Fiction Magazine

Posted by Patty Nicole Johnson on December 31, 2016 at 1:10am

Hi writers!

I'm seeking contributors for a science fiction literary magazine that solely publishes work from authors of color. 

We're aiming for a spring 2017 launch for our first edition. It's a not-for-profit endeavor with a mission to promote the work of POC who are often passed over in the literary realm. 

Interested in submitting a science fiction short story? 

Find more details, here. 

Like to volunteer your talents as a cover artist or illustrator? 

Contact us!

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Speak Up. Keep Focused. Carry On...

Posted by Reginald L. Goodwin on December 23, 2016 at 9:30am
MANY YOUNG SCIENTISTS ATTEND AAAS’ ANNUAL MEETINGS AND THE ONE HELD IN WASHINGTON, D.C. EARLIER THIS YEAR WAS NO DIFFERENT IN BEING A DRAW FOR EARLY-CAREER SCIENTISTS ACROSS SCIENTIFIC DISCIPLINES. | AAAS/ATLANTIC PHOTO


Topics: Commentary, Diversity, Physics, Politics, Research, Science


CEO Rush Holt was a congressional representative from New Jersey. Prior to that, he worked at the Princeton Plasma Physics Lab as a researcher. In his capacity as congressman, he had been one of the few members of our government that had a background in a STEM field. As I said before, sadly and poignantly now there are none.

I thought it appropriate as an end-of-year post. It looks like Dr. Holt is trying to rally the troops (if you're reading this, "us"). Don't be discouraged; don't stop pursuing your dreams. Our love and pursuit of STEM - and I'll include STEAM for artists - is more important now than ever. The future of humanity may well depend upon it.



His encouraging words speak for themselves at the link below.

“If we are not ashamed to think it, we should not be ashamed to say it.” Marcus Tullius Cicero

"In a time of universal deceit - telling the truth is a revolutionary act." Unknown

In the wake of the presidential election, AAAS CEO Rush Holt acknowledged the concerns of young scientists and engineers in an op-ed calling on them to “Speak up, keep calm and carry on.”

Early-career scientists and engineers may be understandably apprehensive about change in Washington, particularly since “attention to science during the presidential campaign was neither appreciable nor appreciative,” wrote Holt for Motherboard. Still, he urged the next-generation of innovators not to despair.

“Science has faced challenges throughout history, from one administration to the next, but year in and year out it has led to human progress, enriching our culture by improving quality of life and human knowledge about our place in the universe,” Holt wrote.

AAAS CEO to Young Scientists: “Speak Up. Keep Focused. Carry On.”
Ginger Pinholster

2 of 2 blog breaks. I'll resume posting in the New Year on Monday, 2 January 2017.
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Subatomic Motion Detector...

Posted by Reginald L. Goodwin on December 22, 2016 at 9:00am
Images Sources: See link below

Topics: Atomic Force Microscopy, Nanotechnology, NEMS, NIST, Thin Films

Scientists at the National Institute of Standards and Technology (NIST) have developed a new device that measures the motion of super-tiny particles traversing distances almost unimaginably small—shorter than the diameter of a hydrogen atom, or less than one-millionth the width of a human hair. Not only can the handheld device sense the atomic-scale motion of its tiny parts with unprecedented precision, but the researchers have devised a method to mass produce the highly sensitive measuring tool.

It’s relatively easy to measure small movements of large objects but much more difficult when the moving parts are on the scale of nanometers, or billionths of a meter. The ability to accurately measure tiny displacements of microscopic bodies has applications in sensing trace amounts of hazardous biological or chemical agents, perfecting the movement of miniature robots, accurately deploying airbags and detecting extremely weak sound waves traveling through thin films.

NIST physicists Brian Roxworthy and Vladimir Aksyuk describe their work (link is external) in the Dec. 6, 2016, Nature Communications.

The researchers measured subatomic-scale motion in a gold nanoparticle. They did this by engineering a small air gap, about 15 nanometers in width, between the gold nanoparticle and a gold sheet. This gap is so small that laser light cannot penetrate it.



However, the light energized surface plasmons—the collective, wave-like motion of groups of electrons confined to travel along the boundary between the gold surface and the air.

The researchers exploited the light’s wavelength, the distance between successive peaks of the light wave. With the right choice of wavelength, or equivalently, its frequency, the laser light causes plasmons of a particular frequency to oscillate back and forth, or resonate, along the gap, like the reverberations of a plucked guitar string. Meanwhile, as the nanoparticle moves, it changes the width of the gap and, like tuning a guitar string, changes the frequency at which the plasmons resonate.

NIST Device for Detecting Subatomic-Scale Motion Has Potential Robotics, Homeland Security Applications
Ben Stein

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