Reginald L. Goodwin's Posts

We Have Met The Enemy...

Posted by Reginald L. Goodwin on March 11, 2016 at 7:02am

Topics: Economy, Education, Large Hadron Collider, LHC, Particle Physics, Politics

I openly and severely date myself once again (the $2.95 cover a dead giveaway), all honor to Walt Kelly coining it the first Earth Day, April 22, 1970. Next month will mark the 46th year we've observed it as science and intelligence have receded from public life.

We're great "gadget consumers": we've just become piss-poor producers.

The Superconducting Supercollider was formally in Waxahatchie, Texas. It's a whole in the ground now. That Higgs Boson discovered at CERN was supposed to be found in the good old US of A.

I sum the current state of affairs with science and the general public in my best "Me Tarzan; you Jane" personification:

- Pseudoscience good;

- Real science BAD.

A primitive grunt, but a personification of the aftermath attacking the education enterprise in this country (vis-à-vis the lucrative teaching-to-the-test industry), and education's absolute necessity in running a democratic republic successfully. We've played chicken with conspiracy provocateurs, climate change deniers, Flat Earth groups, science deniers, vaccine deniers, Young Earth groups and the denial of human self-government itself. These "chickens have come home to roost" (Malcolm X).

Physics and Physicists* had a good blog entry last Friday on the Socio-Economic Impact of the LHC, based on an analysis posted in Physics arXiv (link below). It answers the question "what's in it for me" for Jane and Joe Q. Public, who have to "catch the vision" and support any research typically with their tax dollars, a far better and lasting investment than the boondoggle of sports stadiums.

Like "Zapper Z*" says (the particular physicist's online persona), it's like we don't care, or many of us have been exquisitely conditioned not to care.

Even worse, do we think modern society and its reliance on technology is a combination of fairies, pixie dust, microwave popcorn, three heel clicks of ruby red shoes to Kansas, and a genie with three wishes? It explains our current crisis of governance that one of the front runners seeking the nuclear codes has a LOT more in common with The Kardashians than we'd all care to admit.

..."and he is 'us.'"

Abstract

In this paper we develop a cost-benefit analysis of a major research infrastructure, the Large Hadron Collider (LHC), the highest-energy accelerator in the world, currently operating at CERN. We show that the evaluation of benefits can be made quantitative by estimating their welfare effects on different types of agents. Four classes of direct benefits are identified, according to the main social groups involved: (a) scientists; (b) students and young researchers; (c) firms in the procurement chain and other organizations; (d) the general public, including onsite and website visitors and other media users. These benefits are respectively related to the knowledge output of scientists; human capital formation; technological spillovers; and direct cultural effects for the general public. Welfare effects for taxpayers can also be estimated by the contingent valuation of the willingness to pay for a pure public good for which there is no specific direct use (i.e., as non-use value). Using a Monte Carlo approach, we estimate the conditional probability distribution of costs and benefits for the LHC from 1993 until its planned decommissioning in 2025, assuming a range of values for some critical stochastic variables. We conservatively estimate that there is around a 90% probability that benefits exceed costs, with an expected net present value of about 2.9 billion euro, not considering the unpredictable applications of scientific discovery.

Physics arXiv:

Forecasting the Socio-Economic Impact of the Large Hadron Collider: a Cost-Benefit Analysis to 2025 and Beyond

Massimo Florio, Stefano Forte, Emanuela Sirtori

Space Weather...

Posted by Reginald L. Goodwin on March 10, 2016 at 6:57am

Photo: NASA
Huge solar coronal mass ejections hurl plasma into space. These cause space storms that can wreak havoc on Earth.

Topics: Heliophysics, International Space Station, NASA, Space, Space Exploration

Auroras lit the skies as far south as Cuba on September 1, 1859. Telegraph systems across the globe malfunctioned, sparking and shocking their operators, and making transmission impossible. The cause was a massive geomagnetic storm, known as the Carrington Event after astronomer Richard Carrington, who observed an enormous solar flare preceding the events on Earth.

If a storm of equal strength occurred in today’s technology-addicted world, it would have catastrophic impacts, said a panel of space weather experts at the American Association for the Advancement of Science (AAAS) Meeting in Washington, DC on February 15.

“This was by all measures a huge storm,” said Daniel Baker of the University of Colorado. “If an event of that size were to occur today, the effects by most estimates would be devastating.” Large regions of the globe could be plunged into darkness and hobbled with technology failures, from widespread power outages, to loss of communication systems, to GPS navigation failures, and damage to satellites.

APS News: Scientists Discuss the Dangers of Space Weather, Emily Conover

Staircase Avalanche Photodiode...

Posted by Reginald L. Goodwin on March 9, 2016 at 7:12am

Fig. 1

Conceptual band diagrams of a staircase APD unbiased (top) and under reverse bias (bottom). The arrows below the valance band indicate that holes do not impact ionize.

Citation: Appl. Phys. Lett. 108, 081101 (2016); http://dx.doi.org/10.1063/1.4942370

Topics: Electronics, Photonics, Semiconductor Technology, Quantum Mechanics

An avalanche photodiode is a semiconductor-based photodetector (photodiode) which is operated with a relatively high reverse voltage (typically tens or even hundreds of volts), sometimes just below breakdown. In this regime, carriers (electrons and holes) excited by absorbed photons are strongly accelerated in the strong internal electric field, so that they can generate secondary carriers, as it also occurs in photomultipliers. The avalanche process, which may take place over a distance of only a few micrometers, for example, effectively amplifies the photocurrent by a significant factor. Therefore, avalanche photodiodes can be used for very sensitive detectors, which need less electronic signal amplification and are thus less susceptible to electronic noise. However, the avalanche process itself is subject to quantum noise and amplification noise, which can offset the mentioned advantage. The excess noise is quantified with the excess noise factor F, which is the factor by which the electronic noise power is increased compared with that of an ideal photodetector. *

* Encyclopedia of Laser Physics and Technology: Avalanche Photodiodes

Abstract

Over 30 years ago, Capasso and co-workers [IEEE Trans. Electron Devices 30, 381 (1982)] proposed the staircase avalanche photodetector (APD) as a solid-state analog of the photomultiplier tube. In this structure, electron multiplication occurs deterministically at steps in the conduction band profile, which function as the dynodes of a photomultiplier tube, leading to low excess multiplication noise. Unlike traditional APDs, the origin of staircase gain is band engineering rather than large applied electric fields. Unfortunately, the materials available at the time, principally AlxGa1−xAs/GaAs, did not offer sufficiently large conduction band offsets and energy separations between the direct and indirect valleys to realize the full potential of the staircase gain mechanism. Here, we report a true staircase APD operation using alloys of a rather underexplored material,AlxIn1−xAsySb1−y, lattice-matched to GaSb. Single step “staircase” devices exhibited a constant gain of ∼2×, over a broad range of applied bias, operating temperature, and excitation wavelengths/intensities, consistent with Monte Carlo calculations.

Applied Physics Letters: AlInAsSb/GaSb staircase avalanche photodiode
Min Ren, Scott Maddox, Yaojia Chen1, Madison Woodson1, Joe C. Campbell1 and Seth Bank

Solar Eclipse...

Posted by Reginald L. Goodwin on March 8, 2016 at 6:30am

Image Source: NASA's Marshall Space Flight Facebook Page

Topics: Astronomy, Astrophysics, Eclipse, NASA

The total eclipse will be visible in parts of South East Asia and a partial eclipse will be visible in parts of Alaska, Hawaii, Guam, and America Samoa. An eclipse occurs when the moon passes directly between Earth and the sun. When the moon's shadow falls on Earth, observers within that shadow see the moon block a portion of the sun's light.

Here's all the info for it: NASA Press Release

III-V Semiconductor Superlattices...

Posted by Reginald L. Goodwin on March 7, 2016 at 7:48am

FIG. 1.

Even between lattice-matched crystalline materials, there exist nonuniform transition layers that behave as an effective atomic-scale interface roughness with some rms height Δ. This effective interface roughness leads to phonon-momentum randomization and to interface resistance in cross-plane transport.
Citation: J. Appl. Phys. 118, 175101 (2015); http://dx.doi.org/10.1063/1.4935142

Topics: Applied Physics, Materials Science, Nanotechnology, Phonons, Semiconductor Technology, Solid State Physics, Thermodynamics

Abstract

This paper presents a semiclassical model for the anisotropic thermal transport in III-V semiconductor superlattices(SLs). An effective interface rms roughness is the only adjustable parameter. Thermal transport inside a layer is described by the Boltzmann transport equation in the relaxation time approximation and is affected by the relevant scattering mechanisms (three-phonon, mass-difference, and dopant and electron scattering of phonons), as well as by diffuse scattering from the interfaces captured via an effective interface scattering rate. The in-plane thermal conductivity is obtained from the layer conductivities connected in parallel. The cross-plane thermal conductivity is calculated from the layer thermal conductivities in series with one another and with thermal boundary resistances (TBRs) associated with each interface; the TBRs dominate cross-plane transport. The TBR of each interface is calculated from the transmission coefficient obtained by interpolating between the acoustic mismatch model (AMM) and the diffuse mismatch model (DMM), where the weight of the AMM transmission coefficient is the same wavelength-dependent specularity parameter related to the effective interface rms roughness that is commonly used to describe diffuse interface scattering. The model is applied to multiple III-arsenide superlattices, and the results are in very good agreement with experimental findings. The method is both simple and accurate, easy to implement, and applicable to complicated SL systems, such as the active regions of quantum cascade lasers. It is also valid for other SL material systems with high-quality interfaces and predominantly incoherent phonon transport.

Journal of Applied Physics:
Thermal conductivity of III-V semiconductor superlattices, S. Mei, I. Knezevic

How Much For Half The Planet...

Posted by Reginald L. Goodwin on March 4, 2016 at 7:22am

Image Source: First link, first paragraph

Topics: Diversity in Science, Existentialism, Humor, Science Fiction, Star Trek

I use a derivation of TOS novel, "How Much for Just the Planet?" in the title of this post. Captain Kirk and some Klingons were in brinkmanship (United Federation of Planets = USA; Klingons = Soviets - Cold War, got it?) over Dilithium Crystals (an important commodity in 23rd Century economy for the whole warp drive thing). Lithium exists; dilithium just sounded uber cool, I think. Zephram Cochran apparently did it with good old Earth tech and a CD from Steppenwolf. The article reminded me of it.

The NASA endeavor at its essence ultimately is to avoid a H.E.L.E. - better known as a human extinction level event - a term I was introduced to in the miniseries Heroes Reborn, and the dizzying pseudo paradoxes of teleportation, time travel, self-cloning, telepathy and consciously occupying video games. Er...it has to do with EVOs - a group of humans with evolutionary extraordinary powers, and like most science fiction/modern myth asks questions about humans, humanity, xenophobia and society similar to the X-men (a metaphor for African Americans during the Civil Rights Movement): Charles Xavier née Martin Luther King; Magneto, Malcolm X.

As I'm apt to ask (I did mentally in "Interstellar"): who flies off to the Moon, Mars or Alpha Centauri for the species to survive; who goes to the other half of the planet for the species to survive? And, where exactly is the other half of the planet that's "desirable," and protected/isolated from the effects of climate change?

It may boil down sadly to: 1. Who has trained in a STEM field; 2. Who can afford it.

Edward O. Wilson sees mass extinction of species “among the deadliest threats that humanity has imposed on itself.”

Invoking the kilometers-wide object that struck Earth some 66 million years ago, Edward O. Wilson calls the extinction rate humans are imposing in the biosphere “the equivalent of a Chicxulub-sized asteroid strike played out over several human generations.” His 32nd book, Half-Earth: Our Planet’s Fight for Life, comes out this month. The New York Times and other media have begun reporting the solution it advocates: reserving half the planet to let other species survive and flourish.

Claudia Dreifus writes for the Times’s science section and teaches at Columbia University’s School of International and Public Affairs. In an Audubon Magazine piece, she reminded readers about Wilson’s scientific and public stature:

At 86, Edward Osborne Wilson, Harvard University research professor emeritus of comparative zoology, is among the most famous scientists of our time. Only Jane Goodall and Stephen Hawking can draw a larger crowd. Over the decades he’s made his mark on evolutionary biology, entomology, environmentalism, and literature. In all there have been 31 books, two of which, On Human Nature and The Ants, received the Pulitzer Prize.

She added that he’s widely accepted as “one of the greatest researchers, theorists, naturalists, and authors of our time,” is “known as the father of the concepts of sociobiology and biodiversity,” and is “highly celebrated for his lifetime of environmental advocacy.” Concerning the forthcoming book, she explained that it’s “his answer to the disaster at hand: a reimagined world in which humans retreat to areas comprising one half of the planet’s landmass.” She continued: “The rest is to be left to the 10 million species inhabiting Earth in a kind of giant national park. In human-free zones, Wilson believes, many endangered species would recover and their extinction would, most likely, be averted.”

Physics Today:
Media coverage begins for a book that calls for setting aside half the planet
Steven T. Corneliussen

STEP...

Posted by Reginald L. Goodwin on March 3, 2016 at 8:37am

The Solar Thermal Electrochemical Process (STEP) converts atmospheric carbon dioxide into carbon nanotubes that can be used in advanced batteries. Credit: Julie Turner, Vanderbilt University

Topics: Alternative Energy, Carbon Nanotubes, Climate Change, Global Warming, Green Energy, Green Tech, Greenhouse Gases, Nanotechnology

An interdisciplinary team of scientists has worked out a way to make electric vehicles that are not only carbon neutral, but carbon negative, capable of actually reducing the amount of atmospheric carbon dioxide as they operate.

They have done so by demonstrating how the graphite electrodes used in the lithium-ion batteries that power electric automobiles can be replaced with carbon material recovered from the atmosphere.

The recipe for converting carbon dioxide gas into batteries is described in the paper titled "Carbon Nanotubes Produced from Ambient Carbon Dioxide for Environmentally Sustainable Lithium-Ion and Sodium-Ion Battery Anodes" published in the Mar. 2 issue of the journal ACS Central Science.

The unusual pairing of carbon dioxide conversion and advanced battery technology is the result of a collaboration between the laboratory of Assistant Professor of Mechanical Engineering Cary Pint at Vanderbilt University and Professor of Chemistry Stuart Licht at George Washington University.

Phys.org: Converting atmospheric carbon dioxide into batteries

Back To Earth...

Posted by Reginald L. Goodwin on March 2, 2016 at 4:48pm

Scott Kelly inside the Cupola, a special module which provides a 360-degree viewing of the Earth and the space station, July 12, 2015.
REUTERS/NASA

Topics: International Space Station, Mars, NASA, Planetary Science, Space, Space Exploration, Spaceflight

NASA astronaut Scott Kelly and Russian cosmonaut Mikhail Kornienko headed back toward Earth on Tuesday after nearly a year aboard the International Space Station, ending a record-long U.S. spaceflight intended to pave the way for human travel to Mars.

The men, accompanied by Russian cosmonaut Sergey Volkov, strapped themselves inside a Russian Soyuz capsule and departed the station at 8:02 p.m. EST (0102 GMT on Wednesday).

They are expected to make a parachute landing in Kazakhstan at 11:25 p.m. EST (0425 GMT on Wednesday).

Kelly and Kornienko have been aboard the space station for 340 days, about twice as long as previous crews. Their flight sets a record for the space station and for the longest U.S. space mission.

Reuters Science: Station crew heads home after record U.S. spaceflight, Irene Klotz

Tetraquark Discovery...

Posted by Reginald L. Goodwin on March 1, 2016 at 6:27am

Four flavours: X(5568) has no charm quark/antiquark pair. (Courtesy: Shutterstock/paul_june)

Topics: Particle Physics, Quantum Mechanics, Quarks, Theoretical Physics

A new particle that is a bound state of four different flavours of quarks has been discovered by physicists working on the DØ experiment at Fermilab *. Called X(5568), the particle has a mass of about 5568 MeV/c², and appears to contain "up" and "bottom" quarks as well as "down" and "strange" antiquarks.

Although other tetraquarks have previously been identified, X(5568) is the first in which all of the quarks have different flavours, which could affect our understanding of how quarks interact with each other. The discovery is also notable because X(5568) is produced at a much higher rate in proton–antiproton collisions than had been expected.

The particle was discovered by sifting through data acquired by DØ – an experiment that ran at Fermilab's Tevatron proton–antiproton collider from 2002 to 2011. The statistical significance of the discovery is 5.1σ, which puts it just above the 5σ required for a discovery in particle physics.

* * * * *

* And the X(5568) is not just any new tetraquark. While all other observed tetraquarks contain at least two of the same flavor, X(5568) has four different flavors: up, down, strange and bottom.

“The next question will be to understand how the four quarks are put together,” says DZero co-spokesperson Paul Grannis. “They could all be scrunched together in one tight ball, or they might be one pair of tightly bound quarks that revolves at some distance from the other pair.”

Four-quark states are rare, and although there’s nothing in nature that forbids the formation of a tetraquark, scientists don’t understand them nearly as well as they do two- and three-quark states.

This latest discovery comes on the heels of the first observation of a pentaquark—a five-quark particle—announced last year by the LHCb experiment at the Large Hadron Collider.

Image Source: Fermilab

Physics World: Fermilab bags a tetraquark, Hamish Johnston

Star Trek (repost and add)...

Posted by Reginald L. Goodwin on February 29, 2016 at 7:07am

Topics: African Americans, Diaspora, Diversity, Diversity in Science, Politics, Star Trek, STEAM, STEM, Women in Science

The current vitriol broadcast globally during the political season is enough to cause concern and lose hope. The past is set, yet in many cases its impact on current events ignored to our detriment. The future is malleable and in flux, yet the tools we use to discern it and prepare for it - science - some in our society would have us fear to our peril. As a Trekkie, I lament that the future we used to dream of in 1968 has led to our current morass of flirting with a new form of self-government more like play dough anarchy: "Idiocracy" as I've seen oft-quoted in social media was meant to be a comedy, not a documentary. We have elements of our society "rooting for Armageddon" without a discernible or rational "plan B."

My hope in 2017 when Star Trek returns to CBS, we can recapture that awe, wonder and hope catapulting ourselves from superstition and authoritarianism beyond the ignorant darkness into the light only science in its proper context can give.

All links to Star Trek on this blog here.
Institute for Ethics and Emerging Technologies:
The End: What Science and Religion Tell Us About the Apocalypse, Phil Torres

The vertical scroll (link here) first appeared February 26, 2014, reposted for this leap day.

STEAM...

Posted by Reginald L. Goodwin on February 26, 2016 at 6:39am

Image Source: Science Mag [2]

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

STEAM: science, technology, engineering, art, mathematics recognizes that creative expression expands the intellect and learning. It allows us to be more than "left-brained" or "right-brained" and increases the faculties of individuals in science-related fields.

I of course applaud this and the emphasis on diversity, but forgive me if I'm a bit cynical. Our American Society sadly, is rooted in a structure of divide and conquer: even the SAT, which has no bearing on a student's aptitude or motivation in college, is more of a gatekeeper than an accurate predictor of educational success.

We've foisted this global economy on ourselves without thinking of the consequences. Our children are literally competing with the planet, where creationism and science denial has no place. We'd better get in the business of ensuring all levels of our society have a chance at trade school, community programs and four year colleges, along with the associated employment for them when they need it to start families, and the elimination of loan debt. The current formula will not make us "great again": it will likely lead to modern feudalism, a system inherently undemocratic and non republic.

The National Science Foundation (NSF) wants to make the U.S. scientific community more inclusive. And the more ideas, the better.

This week NSF announced its intention to hand out small grants later this year to dozens of institutions to test novel ways of broadening participation in science and engineering. Winners of the 2-year, $300,000 pilot grants will be eligible to compete next year for up to five, $12.5 million awards over 5 years. NSF is calling the program INCLUDES. (The acronym stands for a real jaw-breaker: inclusion across the nation of communities of learners of underrepresented discoverers in engineering and science.)

The underrepresentation of women and minorities in the scientific workforce is a problem that has persisted for decades despite many well-meaning federal initiatives. NSF Director France Cordova has spoken repeatedly about her intention of moving the needle on the issue since taking office in March 2014. And this initiative, totaling roughly $75 million, could well be the signature program of her 6-year term. [1]

Our culture has drawn an artificial line between art and science, one that did not exist for innovators like Leonardo da Vinci and Steve Jobs. Leonardo’s curiosity and passion for painting, writing, engineering and biology helped him triumph in both art and science; his study of anatomy and dissections of corpses enabled his incredible drawings of the human figure. When introducing the iPad 2, Jobs, who dropped out of college but continued to audit calligraphy classes, declared: “It’s in Apple’s DNA that technology alone is not enough — it’s technology married with liberal arts, married with the humanities, that yields us the result that makes our heart sing.” (Indeed, one of Apple’s scientists, Steve Perlman, was inspired to invent the QuickTime multimedia program by an episode of “Star Trek.”) [2]

1. We don’t need more STEM majors. We need more STEM majors with liberal arts training.
Dr. Loretta Jackson-Hayes
2. NSF launches long-awaited diversity initiative, Jeffery Mervis

Fast Radio Bursts and Missing Matter...

Posted by Reginald L. Goodwin on February 25, 2016 at 6:42am

This image shows the field of view of the Parkes radio telescope on the left. On the right are successive zoom-ins in on the area where the signal came from (cyan circular region). The image at the bottom right shows the Subaru image of the FRB galaxy, with the superimposed elliptical regions showing the location of the fading 6-day afterglow seen with ATCA. Image Credit: D. Kaplan (UWM), E. F. Keane (SKAO).

Topics: Astronomy, Astrophysics, Radio Astronomy

An international team of scientists using a combination of radio and optical telescopes has for the first time managed to identify the location of a fast radio burst, allowing them to confirm the current cosmological model of the distribution of matter in the universe.

On April 18, 2015, a fast radio burst (FRB) was detected by the Commonwealth Scientific and Industrial Research Organisation (CSIRO)'s 64-m Parkes radio telescope in Australia. An international alert was triggered to follow it up with other telescopes and within a few hours, a number of telescopes around the world were looking for the signal, including CSIRO's Australian Telescope Compact Array (ATCA).

FRBs are mysterious bright radio flashes generally lasting only a few milliseconds. Their origin is still unknown, with a long list of potential phenomena associated with them. FRBs are very difficult to detect; before this discovery only 16 had been detected.

"In the past FRBs have been found by sifting through data months or even years later. By that time it is too late to do follow up observations." says Dr Evan Keane, Project Scientist at the Square Kilometre Array Organisation and the lead scientist behind the study. To remedy this, the team developed their own observing system to detect FRBs within seconds, and to immediately alert other telescopes, when there is still time to search for more evidence in the aftermath of the initial flash.

Phys.org: New fast radio burst discovery finds 'missing matter' in the universe
Published in Nature
#P4TC: FRBs...

For The Better...

Posted by Reginald L. Goodwin on February 24, 2016 at 4:14am

Illustration: Takashi Takahashi/Tohoku University

Topics: Condensed Matter Physics, Graphene, Materials Science, Nanotechnology, Semiconductor Technology, Superconductors, Solid State Physics, Quantum Mechanics

Graphene is an amazing conductor. The transport of electrons through graphene nanoribbons has even surpassed what scientists thought were the theoretical limits for the material—so much so that electrons moving through it seem to behave almost like photons.

Graphene’s amazing properties as a conductor has inspired some researchers to explore whether the single-atom-thick sheets of carbon could also be made into superconductors. Last year, an international research team from Canada and Germany was able to demonstrate that graphene can be made to behave that way when it’s doped with lithium atoms.

Now researchers in Japan (from Tohoku University and the University of Tokyo) have developed a new method for coaxing graphene to behave as a superconductor that has some important and distinctive differences from the previous research by the Canadian and German researchers.

IEEE: Graphene's Role as a Superconductor Just Got Better, Dexter Johnson

Chiral Molecules...

Posted by Reginald L. Goodwin on February 23, 2016 at 6:27am

The circular dichroism spectra for short spirals (red) and long spirals (blue). For longer spirals there is a red shift in the mode in the visible regime but not for the mode in the UV. Courtesy Nanotechnology.

Topics: Biology, Chemistry, Materials Science, Nanotechnology

The chirality of molecular structures can significantly affect a substance’s effect on biological systems, but the low signal means distinguishing chiral signals can be challenging. Fledgling studies in chiral plasmonics hope to exploit the resulting enhancements in chiral detection, just as molecular sensing has benefited from techniques like surface-enhanced Raman scattering. Now researchers have extended the understanding of chiral plasmonics by identifying how structural parameters affect the chiral plasmon signals from silver nanospirals.

"This is like where we were in the 1990s with plasmons," says Zhifeng Huang, associate professor in the Physics Department at Hong Kong Baptist University (HKBU), who led this latest research. "People have been wondering whether it is possible to use chiral plasmons to amplify the signal of chiral molecules, but first we need to understand chiral plasmons." The stakes are high for enhancing chiral signal detection and differentiation, since it has an impact on pharmaceuticals, agriculture, food quality monitoring and control, disease diagnosis and treatment, and environmental protection and sustainable development.

Chirality refers to a property of structures that exist in two versions - "enantiomers" - that are mirror images of each other but cannot be superimposed. Examples of chiral molecules include penicillamine, where the right-handed version is effective for rheumatoid arthritis therapy, whereas the left-handed version is toxic, or aspartame, where the left-handed version tastes sweet and has been patented in the food industry, whereas the right-handed version is tasteless.

Nanotechweb: Helical structures affect chiral plasmons, Anna Demming

Copernican Principle...

Posted by Reginald L. Goodwin on February 22, 2016 at 5:20am

NASA/ESA/ESO

Topics: Astronomy, Astrophysics, Cosmology, Exoplanets, SETI, Theoretical Physics

A new tally proposes that roughly 700 quintillion (10¹⁸) terrestrial exoplanets are likely to exist across the observable universe—most vastly different from Earth

More than 400 years ago Renaissance scientist Nicolaus Copernicus reduced us to near nothingness by showing that our planet is not the center of the solar system. With every subsequent scientific revolution, most other privileged positions in the universe humans might have held dear have been further degraded, revealing the cold truth that our species is the smallest of specks on a speck of a planet, cosmologically speaking. A new calculation of exoplanets suggests that Earth is just one out of a likely 700 million trillion terrestrial planets in the entire observable universe. But the average age of these planets—well above Earth’s age—and their typical locations—in galaxies vastly unlike the Milky Way—just might turn the Copernican principle on its head.

Astronomer Erik Zackrisson from Uppsala University and his colleagues created a cosmic compendium of all the terrestrial exoplanets likely to exist throughout the observable universe, based on the rocky worlds astronomers have found so far. In a powerful computer simulation, they first created their own mini universe containing models of the earliest galaxies. Then they unleashed the laws of physics—as close as scientists understand them—that describe how galaxies grow, how stars evolve and how planets come to be. Finally, they fast-forwarded through 13.8 billion years of cosmic history. Their results, published to the preprint server arXiv (pdf) and submitted to The Astrophysical Journal, provide a tantalizing trove of probable exoplanet statistics that helps astronomers understand our place in the universe. “It's kind of mind-boggling that we're actually at a point where we can begin to do this,” says co-author Andrew Benson from the Carnegie Observatories in California. Until recently, he says, so few exoplanets were known that reasonable extrapolations to the rest of the universe were impossible. Still, his team’s findings are a preliminary guess at what the cosmos might hold. “It's certainly the case that there are a lot of uncertainties in a calculation like this. Our knowledge of all of these pieces is imperfect,” he adds.

Scientific American: Exoplanet Census Suggests Earth Is Special after All
Shannon Hall

Future Engineers...

Posted by Reginald L. Goodwin on February 19, 2016 at 7:10am

Image Source: Tokyo Tech

Topics: 3D Printing, Humor, NASA, Science Fiction, Space Exploration, Star Trek, STEM

I kind of tackled this in the posts Tea, Earl Grey and Kardashev Scales, essentially we're likely not to achieve the clearly miracle technologies that would violate the Heisenberg Uncertainty Principle (I'm pretty certain about that!).

However, the closest approximation to replicators are the 3D printing systems that are becoming almost routine; some mentioned even in the same breath as the 2nd Amendment strangely enough.

It is good, with Star Trek due in 2017 to start now to engage the young in STEM activities that will lead ultimately to the next generation of scientists and engineers that will get us to Mars and beyond.

And, for that consequential and monumentally long journey (barring we survive our own hubris to make the actual trek): we shall have to EAT.

NASA, ASME, Star Trek Challenge Future Engineers to Turn Science Fiction into Science Fact
Future Engineers: Star Trek Replicator Challenge

GCM...

Posted by Reginald L. Goodwin on February 18, 2016 at 7:15am

Image Source: NOAA

Topics: Climate Change, Computer Science, Global Warming, Research, STEM, Stochastic Modeling

Whenever news breaks about what Earth's climate is expected to be like decades into the future or how much rainfall various regions around the country or the world are likely to receive, those educated estimates are generated by a global climate model.

But what exactly is a climate model? And how does it work?

At its most basic, a global climate model (GCM) is a computer software program that solves complex equations that mathematically describe how Earth's various systems, processes and cycles work, interact and react under certain conditions. It's math in action.

A global model depends on submodels

Submodels can be broken into two classes: dynamics and physics. Dynamics refers to fluid dynamics. The atmosphere and the ocean are both treated mathematically as fluids. The physics class includes natural processes such as the carbon organic soil respiration cycle and sunlight as it passes though and heats the atmosphere.

Just as Earth's major systems and spheres — the atmosphere, the biosphere, the hydrosphere and the cryosphere — interact with and influence each other, so too must the subprograms in a climate model that represents them. This is accomplished through a technique called coupling, in which scientists develop additional equations and subprograms that knit together divergent submodels. That's what climate researcher Rob Jacob does at the U.S. Department of Energy's (DOE) Argonne National Laboratory.

Argonne National Laboratory:
Scientists compose complex math equations to replicate behaviors of Earth systems
Angela Hardin

Light-Effect Transistor...

Posted by Reginald L. Goodwin on February 17, 2016 at 11:56am

Image Source: MIT Technology Review

Topics: Consumer Electronics, Electrical Engineering, Economy, Nanotechnology, Optics, STEM

This caught my eye working in the industry, especially since the doping of silicon or germanium substrates requires the introduction of impurities at high energies and many of them poisonous to humans, hence the great control we use in manufacture. My guess (or, my hope) is this will in some extent prove cleaner as well as cheaper to produce.

TECHNOLOGY REVIEW: The field effect transistor is the workhorse of the consumer electronics industry. Carved into microchips in the billions, these devices beaver away, more or less unnoticed, in practically every home, office, and laboratory in the developed world.

And yet there is a perennial problem with field effect transistors that keeps chip designers awake at night—how to make them ever smaller and thereby keep up the relentless pace of Moore’s Law.

These silicon layers have to be doped with other atoms—just a handful will do the trick in such small components. And therein lies the problem. Even small random variation in the number of dopant atoms in semiconductor components can have a huge effect on the behavior of the transistor. How to control these variations during manufacture is by no means clear. Then there is the physical problem of making a device with three terminals even smaller.

Today, Jason Marmon at University of North Carolina in Charlotte and a few pals unveil just such a device in the form of a light effect transistor. This is essentially a wire that conducts when it is bathed in light and insulates when it is dark. In other words, it is a switch modulated by light. The team says its new device is simpler than a field effect transistor and does not rely on dopant atoms, so it can be made smaller and thereby continue Moore’s law.

Abstract

Modern electronics are developing electronic-optical integrated circuits, while their electronic backbone, e.g. field-effect transistors (FETs), remains the same. However, further FET down scaling is facing physical and technical challenges. A light-effect transistor (LET) offers electronic-optical hybridization at the component level, which can continue Moore's law to the quantum region without requiring a FET's fabrication complexity, e.g. a physical gate and doping, by employing optical gating and photoconductivity. Multiple independent gates are therefore readily realized to achieve unique functionalities without increasing chip space. Here we report LET device characteristics and novel digital and analog applications, such as optical logic gates and optical amplification. Prototype CdSe-nanowire-based LETs show output and transfer characteristics resembling advanced FETs, e.g. on/off ratios up to ~1.0x10^6 with a source-drain voltage of ~1.43 V, gate-power of ~260 nW, and subthreshold swing of ~0.3 nW/decade (excluding losses). Our work offers new electronic-optical integration strategies and electronic and optical computing approaches.

Physics arXiv:
Light-effect transistor (LET) with multiple independent gating controls for optical logic gates and optical amplification
Jason K. Marmon, Satish C. Rai, Kai Wang, Weilie Zhou, Yong Zhang

Ultrasound Resolution...

Posted by Reginald L. Goodwin on February 16, 2016 at 6:52am

Figure 1. Superresolution ultrasound image of the blood vessels in the cortex of a rat’s brain. The colors represent velocity: Dark and light blue indicate blood flow in the direction of the skull (toward the top of the image), and red and yellow indicate flow away from the skull. (Courtesy of Mickael Tanter.)

Citation: Phys. Today 69, 2, 14 (2016); http://dx.doi.org/10.1063/PT.3.3069

Topics: Acoustic Physics, Applied Physics, Biology, Cancer, Nobel Prize, Research

With an acoustic analogue of a Nobel Prize–winning optical technique, researchers can acquire detailed images quickly.

In many ways, ultrasound waves are ideally suited to noninvasive biomedical imaging. They’re easy and inexpensive to produce and detect, and they can penetrate deep into tissue without losing their coherence or causing damage. But because of diffraction, conventional ultrasound imaging—like conventional optical microscopy—is limited in resolution to about half a wavelength. In clinical ultrasound applications, which use wavelengths between 200 µm and 1 mm, that limit precludes the imaging of many important structures, including small blood vessels. Shorter wavelengths yield better resolution, but they also penetrate less deeply into tissue.

For optical applications, innovative fluorescence techniques have been devised to overcome the diffraction limit, as recognized by the 2014 Nobel Prize in Chemistry (see Physics Today, December 2014, page 18). Inspired by that work, Mickael Tanter and his colleagues at the Langevin Institute (affiliated with ESPCI, Inserm, and CNRS) in Paris have now developed a superresolution ultrasound technique,1 which they’ve used to image the blood vessels in a rat’s brain with 10-µm resolution, as shown in figure 1. Applying the technique in humans could help to detect cancer and other diseases that alter blood-flow patterns.

Physics Today: Ultrasound resolution beats the diffraction limit, Johanna L. Miller

Branches...

Posted by Reginald L. Goodwin on February 15, 2016 at 7:30am

Climate Action Reserve: Environmental Cartoons by Joel Pett

Topics: Climate Change, Global Warming, Greenhouse Gases, Politics

This post appears on President's Day. I started it last Wednesday. I say this to respect the family of Justice Antonin Scalia in their time of loss.

We have three co-equal branches of government: the Executive, the Legislative and the Judiciary. It is the "check-and-balance," purposely designed to be slow and plodding; arduous to not make changes quickly as would a despot subjecting a population to h/er will.

It is the judiciary - the Supreme Court - that blocked the Clean Power Plan.

"The Clean Power Plan is based on a strong legal and technical foundation, gives states the time and flexibility they need to develop tailored, cost-effective plans to reduce their emissions, and will deliver better air quality, improved public health, clean energy investment and jobs across the country, and major progress in our efforts to confront the risks posed by climate change," Earnest said. "We remain confident that we will prevail on the merits." *

As I said in Umbilical Cord, old money is inexorably addicted to making its wealth the way it wants to. Mayan pyramids aren't even safe. That means broadcasting counter propaganda that casts doubt (as they did for the cigarette industry); purchasing politicians both locally and nationally; influencing presidential elections because presidents appoint supreme court justices.

Clarence Thomas was appointed in 1991 by George Herbert Walker Bush, post the infamous Willie Horton adds in 1988. During his contentious confirmation hearings, accusations of sexual harassment came in sworn testimony by his former employee Anita Hill. His artful dodge and use of the term "high-tech lynching," made his enemies back off and cleared his confirmation to the Supreme Court. He's apparently been quiet as a church mouse ever since. His first major decision was finalized December 12, 2000, deciding the Florida "hanging chads" fiasco by a 5-4 vote:

- The same 5-4 vote that decided the Hobby Lobby decision;

- The same 5-4 vote that gutted the Voting Rights Act.

He has so far served six times the president that appointed him: 1991 - 2016 is 25 years, a generation. He may be silent, but he's darkly effective in forwarding a regressive, authoritarian agenda that will outlive him.

Do not fall in love with the person on the top of presidential tickets. I cannot get emotional about people I'll likely never meet. Don't get excited for the top ticket major elections and neglect the midterms. It is a failure to teach Civics that we have citizens so caught up in the hype of inflated campaigns that we forget we're not electing "kings": we're electing representatives of our will ["We The People"], not the moneyed few; the function and genius of a democratic republic.

However, what lives beyond any administration is who is appointed to the court and if fairly young, how LONG they serve.

A generation is an incredibly long time...to do lasting damage. The damage in this case can be the environment for generations the families of the justices are also subject to:

“Only when the last tree has been cut down, the last fish been caught, and the last stream poisoned, will we realize we cannot eat money.”

Cree Indian Prophecy, GoodReads

* CNN: Supreme Court blocks Obama climate change rules
Ariane de Vogue, Dan Berman and Kevin Liptak