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Plasmas Without Solenoids...

Posted by Reginald L. Goodwin on November 14, 2016 at 7:11am
Left: Plasmoid formation in simulation of NSTX plasma during startup without solenoid. Right: Fast-camera image of NSTX plasma shows two discrete plasmoid-like structures. Credit: NSTX


Topics: Applied Physics, Nuclear Fusion, Plasma Physics, Research


The tokamak is an experimental chamber that holds a gas of energetic charged particles, plasma, for developing energy production from nuclear fusion. Most large tokamaks create the plasma with solenoids—large magnetic coils that wind down the center of the vessels and inject the current that starts the plasma and completes the magnetic field that holds the superhot gas in place. But future tokamaks must do without solenoids, which run in short pulses rather than for weeks or months at a time as commercial fusion power plants will have to do.

Recent computer simulations have suggested a novel method for launching the plasma without using solenoids. The simulation modeling shows the formation of distinct, current carrying magnetic structures called plasmoids that can initiate the plasma and complete the complex magnetic field.

Everything starts with magnetic field lines, or loops, that rise through an opening in the floor of the tokamak. As the field lines are electrically forced to expand into the vessel, a thin layer, or sheet, of electrical current can form. Through a process called magnetic reconnection, the sheet can break and form a series of ring-shaped plasmoids that are the magnetic equivalent to the bubble rings created by dolphins.

Phys.org: Launching fusion reactions without a central magnet, or solenoid

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Van Bullock...

Posted by Reginald L. Goodwin on November 11, 2016 at 7:27am
Image Source: Unapologetically American


Topics: Civics, Civil Rights, Politics, Veterans Day


To my fellow veterans: happy Veteran's Day. I salute your Giri (Japanese): duty, obligation, honor to this nation.

Van Bullock (R.I.P.) was my ninth grade Social Studies Teacher. He was a short, stocky man with an impressive bearing and presence, white-haired mop hairdo kind of like Moe Howard of the Three Stooges in wire progressive lenses. It was 1976, our country's Bicentennial year, 8 years after the assassinations of Martin Luther King and Bobby Kennedy as the country tried mightily to build bridges in the place of previous De Jure and De Facto walls. Mr. Bullock's teaching technique was using stenciled notes he passed out to all of us, particularly me and Ve Pauling and lecturing with the fire of a camp meeting preacher. (Ve is my fraternity brother in Kappa Alpha Psi; he and I realized at A&T's homecoming - GHOE last month that we've known each other since the fifth grade, attending middle school, high school and college together.) It was pre-Cable Service; pre-24-hour entertainment and news; pre-Internet. It was three years before the first rap song - King Tim the III, Personality Jock, and the first rap album - The Sugar Hill Gang burst on the scene my junior year. Fashion for me centered around acne, Afros and Bell Bottoms. The distractions in class might have been an unannounced fart, a pretty girl next to you or a view outside the classroom window.

Van Bullock would lecture and captivate a crowd of 25 fourteen-year-old teens from view and girls that HAD the notes in front of us: we still took notes in the margins, on the back of each stenciled page. Tests were open book, open note and challenging: he expected great detail and essay answers. The name of the class was Social Studies, but what he was teaching was lessons of citizenship: Civics.

Civics (n): the study of the rights and duties of citizens and of how government works. Meridian-Webster online

Mr. Bullock was teaching Civics because he had the freedom to do so. He was not held to the standard of preparing students for a high-stakes standardized test because no such machination existed from the testing industrial complex. He did not have the pressure of "teaching to the test" with the wink-and-nod from Principal and Superintendent stating the party line that you were not to, knowing full well your end-of-year evaluation depended on how a teenager who's frontal lobe could misfire on the very DAY of that high-stakes exam, put his head down and take a nap...>_<

Van Bullock was teaching all of us, in a forced-bused integrated class in East Winston the rudimentary fundamentals of citizenship. Though forced, it exposed us beyond our cultures and expanded our tolerance, friendships and spheres of influence. We were learning - side-by-side - together. We looked different, we lived on different sides of town and if we attended worship centers probably had different perspectives on that as well. We could all agree that learning those building blocks to take on the responsibilities of the adulthood and the world we were all growing up into was important. We had classroom debates; mock elections: history came alive in that man's room! We learned (hopefully putting a few at ease), to make, change or ABOLISH a Constitutional Amendment it takes a 2/3 majority in both houses of congress (67 senators; 292 house members) and 3/4 of the states - 38 in our case - to ratify it in their legislatures. I tried to capture and emulate that magic every time I taught physics and math at Manor High School. Sometimes I was successful; sometimes I wasn't.

I assumed wrongly that this would always be the focus of our nation's education enterprise, preparing citizens for ownership of our federal republic.

I am sadly aware Mr. Bullock, quite clearly that it is not.
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Supersolids...

Posted by Reginald L. Goodwin on November 10, 2016 at 7:00am
Electron snapshot: the probable position of the remaining helium electron after photoionization. (Courtesy: M Ossiander/ TUM, M Schultze/ MPQ)

Topics: Applied Physics, Bose-Einstein Condensate, Condensed Matter Physics, Materials Science

Fresh evidence for a new state of matter called a supersolid has been put forth by two independent teams of physicists. Supersolidity has been a controversial concept whereby some atoms in a solid material are able to form a superfluid at very low temperatures – allowing them to flow ghost-like through the solid without any resistance. While initial observations of supersolidity in solid helium-4 in the 2000s have since been explained in terms of more mundane physics, some physicists believe that supersolids should exist – at least in principle. Now, Wolfgang Ketterle and colleagues at the Massachusetts Institute of Technology in the US and Tilman Esslinger and colleagues of ETH Zürich in Switzerland have created supersolid analogues using ultracold atoms. Both systems comprise Bose–Einstein condensates (BEC), which are already superfluids. The teams used different optical techniques to make the atoms arrange themselves into crystalline structures of high and low density resembling a solid. They then showed that the atoms can flow freely through such crystals, while the regions of high and low density do not move. While these experiments involve dilute gases, rather than actual solids, both studies show that the supersolid state of matter is possible. Both experiments are described in preprints on arXiv.

Physics World: Have supersolids been seen at last? Hamish Johnston

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Atomtronics...

Posted by Reginald L. Goodwin on November 9, 2016 at 5:30am
[Credit: C. Suplee/NIST]

Topics: Atomic Physics, Bose-Einstein Condensate, Diversity in Science, Nanotechnology, Quantum Mechanics, Semiconductor Technology, Women in Science

Gretchen Campbell describes the new and emerging field of atomtronics, which seeks to make circuit-like devices with extremely cold atoms.

When Gretchen Campbell entered graduate school in 2001, Bose-Einstein condensates (BECs) were still a novelty. Today, says Campbell, an atomic physicist at the Joint Quantum Institute (JQI) of the University of Maryland and the National Institute of Standards and Technology (NIST), researchers have moved beyond exploring the properties of these extremely cold collections of atoms, which behave like giant quantum waves. Instead, they’re using BECs as tools to study other kinds of physics. In Campbell’s field of atomtronics, for example, scientists are manipulating BECs with light to engineer systems that mimic transistors and other circuit components, or function as entirely new devices. The group she leads at the JQI has fabricated and studied a tiny ring of BEC intercepted in one spot by laser light that acts as a barrier for the atoms. Rotating this spot around the ring causes the system to behave like a superconducting quantum interference device, or SQUID, a sensitive detector of magnetic fields. Campbell, who initially wanted to be a vet, spoke with Physics about what attracted her to atomic physics and the many experiments that she’d like to try with ring-shaped BECs.
Image Source: Improved Isotope Enrichment, #P4TC


How do you describe atomtronics to someone outside of physics?


One of the properties of ultracold atoms is that they behave as a superfluid. People have proposed that it’s possible that we could use this superfluid behavior to create circuits, in which the atoms take the place of electrons. There have been some proposals to create analogs of conventional electronics. Others say, hey, let’s take advantage of the qualities of ultracold atoms that are distinct from electrons and see if we can make new types of devices and sensors.

What are these distinct qualities?


Since BECs behave as a superfluid, this means that if we create currents in our atomtronic circuits, they will persist, in much the same way that a superconducting current will persist in a loop of superconducting wire. Now, with BECs you have coherence, which you wouldn’t have in, say, a conventional electronic system. We also have the advantage that we can control the internal states of the atoms.
Image Source: NASA Cold Atom Laboratory, International Space Station

I take it there aren’t any practical atomtronics devices in existence yet?


Yeah, not at all.

If you had to guess, what do you think the first one might be?


I don’t really know. We’ve demonstrated a proof-of-principle rotation sensor: In our ring-shaped device, the current of the BEC will change when the rotating laser spot reaches a critical rotation rate. The rate associated with this transition will shift if the BEC itself experiences a rotational acceleration, so measuring the shift allows us to measure rotation. But because our device is so small—the rings are only 100 micrometers—it’s perhaps best suited for measuring changes in acceleration on a very small length scale. One always hopes that down the road there will be a practical application, but right now I’d say atomtronics is completely driven by fundamental physics.

APS Physics: Things You Can Do with a Loop of Cold Atoms, Jessica Thomas
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Lasers and Anti-Lasers...

Posted by Reginald L. Goodwin on November 8, 2016 at 7:52am
Schematics above show light input (green) entering opposite ends of a single device. When the phase of light input 1 is faster than that of input 2 (left panel), the gain medium dominates, resulting in coherent amplification of the light, or a lasing mode. When the phase of light input 1 is slower than input 2 (right panel), the loss medium dominates, leading to coherent absorption of the input light beams, or an anti-lasing mode. Credit: Zi Jing Wong/UC Berkeley


Topics: Laser, Modern Physics, Optical Physics


Bringing opposing forces together in one place is as challenging as you would imagine it to be, but researchers in the field of optical science have done just that.

Scientists at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have for the first time created a single device that acts as both a laser and an anti-laser, and they demonstrated these two opposite functions at a frequency within the telecommunications band.

Their findings, reported in a paper to be published Monday, Nov. 7, in the journal Nature Photonics, lay the groundwork for developing a new type of integrated device with the flexibility to operate as a laser, an amplifier, a modulator, and an absorber or detector.

"In a single optical cavity we achieved both coherent light amplification and absorption at the same frequency, a counterintuitive phenomenon because these two states fundamentally contradict each other," said study principal investigator Xiang Zhang, senior faculty scientist at Berkeley Lab's Materials Sciences Division. "This is important for high-speed modulation of light pulses in optical communication."

Phys.org:
Lasers + anti-lasers: Marriage opens door to development of single device with exceptional range of optical capabilities

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Solar Steam Generator...

Posted by Reginald L. Goodwin on November 7, 2016 at 6:00am
Figure 1. A three-layer steam generator consists of a selective absorber insulated above with bubble wrap and below with polystyrene foam. Because conductive, convective, and radiative losses are suppressed, most of the solar heat captured by the absorber is channeled to a small slot where the absorber is in contact with water. (Adapted from ref. 1 .)

Citation: Phys. Today 69, 11, 17 (2016); http://dx.doi.org/10.1063/PT.3.3351


Topics: Climate Change, Global Warming, Green Energy, Green Tech, Solar Power


A combination of inexpensive materials collects and concentrates heat from the Sun.

Heating water to its boiling point is an important first step not only for preparing a cup of tea or a bowl of pasta, but for a range of applications fundamental to an industrial society, including distillation, sterilization, and power generation. In a solar economy, one could boil water with an electric heater powered by a photovoltaic cell. But it would be far more efficient to use solar energy to heat the water directly.

That’s manifestly possible. For decades solar steam turbines in wide-open sunny spaces have used arrays of mirrors to concentrate sunlight from a large area onto a small volume of water. But those mirrors are expensive: They must be precisely machined to focus light over several hundred meters, and they must be mounted on motors to track the Sun’s position in the sky. Because the motors require that a powerful source of electricity already be available, optical concentrating arrays aren’t suitable to smaller-scale or off-the-grid applications, such as sterilizing medical instruments in a clinic in the developing world.

Now MIT’s Gang Chen, George Ni, and their colleagues have demonstrated a different approach: concentrating not the Sun’s light but its heat.1 Because their steam generator consists entirely of commonly available materials—a conscious choice on their part—they estimate that per unit area, it could be built for just 1–3% of the cost of an array of motorized mirrors.

The device is sketched in figure 1. It works by absorbing solar energy over a large area but giving it nowhere to escape except through a small slot where the absorber is in contact with a reservoir of ambient-temperature water. If the absorption area is large enough and the contact area is small enough, the water is locally brought to a boil to release steam before the heat can diffuse out into the bulk liquid. The challenge, then, is to keep the absorber from losing too much heat to conduction, convection, and radiation. Normally—and not unfortunately—those losses prevent any object heated by unconcentrated sunlight from getting anywhere near 100 °C.

To limit conductive and convective losses, the researchers insulated the top and bottom of the absorbing layer. For the bottom layer, they used ordinary polystyrene foam, which also kept the device afloat. The choice of top layer was a bit more constrained, because they needed something optically transparent. So they tried bubble wrap. “I was surprised by how well the bubble wrap worked,” said Ni. “Most researchers are using high-performance materials, and here we were, testing out bubble wrap, which wasn’t designed for maximum optical clarity.” Indeed, the bubble wrap transmits only 80% of the light that hits it. But its insulation benefits far outweighed that modest optical inefficiency.

Physics Today: Solar steam generator needs no lenses or mirrors, Johanna L. Miller

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My Review of Dr. Strange

Posted by Rod Van Blake on November 6, 2016 at 4:30pm
DR. STRANGE THE IMPOSSIBILITIES MAY BE ENDLESS BUT THEY GOT SOME OF THEM WRONG.ROD VAN BLAKEDr. Strange#MarvelDr. Strange the impossibilities may be endless but they got some of them wrong.November 6, 2016 at 13:12PMPosted by Rod Van Blake @KisonAskariFormer Marine, scifi author, and unashamed adult gamer who loves all things scifi and Fantasy. Living the life in the Virgin Islands #IAN1I'm a day late with my review but here it is. I got a chance to go check out Marvel's new adaptation of Dr. Strange and for the most part it was well done. Benedict Cumberbatch looks the part and plays a good arrogant, self absorbed neurosurgeon. Most people familiar with the comic book origins will be familiar with this story and newcomers will find things easy to understand and it's all very well presented. The special effects were what can be expected of a sci-fi/fantasy film of today.I have never indulged but often wondered how the experience would have gone if I had been tripping on acid or some other neuro-tropic drug while watching this in 3-D. I bet I would likely be freaking out quite a bit as the characters repeatedly bent time and space to manipulate the environments during the fight scenes. It was a fun ride and the writers for the most part remained faithful to the source material, but for some reason added a casting change that has been a topic of hot debate since the release of the cast some time ago.First let me go through the casting choices I liked aside from the aforementioned Cumberbatch casting. Mordo is played by Chiwetel Ejiofor whom I have liked a lot ever since seeing him in Serenity. The rigidity and at times uncompromising aspects of this character are well portrayed and he seems to have good chemistry with Cumberbatch as well as a lack thereof when they are supposed to be at odds.Baron MordoMads Mikkelsen who seems to have been around forever as a perennial bad guy in films plays Kaecilius, one of the bad guys in the film is interesting. I'm not sure if there was enough of him featured so we could have done with more screen time for this character. He's obviously had a lot of experience in similar roles and when he is there he doesn't disappoint and is not too cliche despite the role of misguided apprentice gone wrong being an old and over used trope at best.KaeciliusBenedict Wong funnily enough plays Wong the librarian for an old order after the old one was killed after an ancient ritual was stolen and Rachel McAdams plays as Dr. Stephen Strange's colleague/off again on again love interest. From what I hear no one has had any problems with those castings. I like them as well.WongWong is affable and also has some good chemistry with the other actors. It took me a second to recognize him as the Khan in the Netflix original Marco Polo. He is the lone Asian in a prominent role in this film which is where most of the tension surrounding the last casting choice I am going to mention. They cast Tilda Swinton as the Ancient One.Tild Swinton and the Comic versionNow first off my main beef with this is that it strays too far from the source material. Swinton did a great job with the role but it's not a casting choice I personally would have made. Marvel defended the choice by saying it was a win for diversity by giving a woman a prominent role while avoiding the "dragon lady" stereotype by choosing NOT to place an Asian woman in the role. The Media Action Network for Asian Americans (MANAA) of course went on the attack in light of the history of "whitewashing" roles in Hollywood and I have to side with them on this. Why?The Ancient One and MordoLook no further than the good diverse casting choice they gave us with Mordo. He's intelligent, badass, and has his own moral code that he abides by. They cast a black man who was not willfully ignorant or just there for comic relief which is done often so I find it hard to believe they could not have executed a similar casting using an Asian woman while avoiding making her portrayal seem like an overbearing dragon lady. It's true that the role of Sorcerer Supreme and the Ancient One rotates but the point I am making is that it could have been done. I also urge anyone out there who feel underrepresented to create your own characters! It's one of the reasons I began writing my own science fiction tale and will also be doing Fantasy as well. If they don't give you what you want go out and make it yourself for you and others out there who may feel the way you do.That's not to say Swinton did a bad job, but in this day and age you have to be more sensitive to how things are perceived. It's not as if this is an unknown phenomena after reaction from castings in Gods of Egypt and Exodus brought about uproar.In conclusion I would say if you're a fan of Marvel and Dr. Strange go see this film but if you abstain because you feel strongly about the casting faux pas I understand. It has some funny moments, witty moments, and can be predictable but that's not uncommon. The visuals are amazing and tie nicely into the Marvel cinematic universe. There's a chance they can fix the mistake going forward as it looks as if Dr. Strange will continue as a character to be featured later. Let me know what you think.

https://creators.co/@KisonAskari/4141576

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Do You Like to Read Sci-Fi?

Posted by Bill McCormick on November 5, 2016 at 1:10pm

Stupid question, I know. Why else would you be on this blog? A better question might be "Do you like to read sci-fi for free?" If the answer to that is HELL TO THE YEAH!! then head over to my site, link below, and click on the short stories page. I put up a bunch of my, previously released, stuff for you to peruse. Of course, if that bonus check is burning a hole in your wallet, my comic book, LEGENDS PARALLEL, and my novel, THE BRITTLE RIDERS, are for sale on their respective pages. I'm more than willing to let you buy them.

Let me know your thoughts if you check anything out.

BILL McSCIFI

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WMD and Proxies...

Posted by Reginald L. Goodwin on November 4, 2016 at 6:49am
Image Source: Link below


Topics: Consumer Electronics, Economy, Internet of Things, Jobs, Mathematical Models


Data science in our interconnected world is beyond big, and becoming more so with the advent of the Internet of Things in consumer electronics.

However, it would be remiss to not know the genesis of big data in a 50s innovation by the banking industry: credit cards. They are the status symbols of "success," in reality just another bill to pay.

They are also a means companies use to screen potential hires despite their resumes, experience or in-person interview performance. It likely exacerbates the growing gap in income inequality. If some want to take us metaphorically back to the days of misogynistic Madmen, Fonzie and Chachi (Emmett Till and pre Rosa Parks), in many ways we're already there.

Credit scores are one of the formulas that determine our world. They often work against us, from job prospects to how long we’re on hold.

When I was little, I used to gaze at the traffic out the car window and study license plate numbers. I would reduce each one to its basic elements — the prime numbers that made it up. 45 = 3 x 3 x 5. That’s called factoring, and it was my favorite investigative pastime.

My love for math eventually became a passion. I went to math camp when I was 14 and came home clutching a Rubik’s Cube to my chest. Math provided a neat refuge from the messiness of the real world. It marched forward, its field of knowledge expanding relentlessly, proof by proof. And I could add to it. I majored in math in college and went on to get my Ph.D. Eventually, I became a tenure-track professor at Barnard College, which had a combined math department with Columbia College.

And then I made a big change. I quit my job and went to work as a quantitative analyst for D. E. Shaw, a leading hedge fund. In leaving academia for finance, I carried mathematics from abstract theory into practice. The operations we performed on numbers translated into trillions of dollars sloshing from one account to another. At first I was excited and amazed by working in this new laboratory, the global economy. But in the autumn of 2008, after I’d been there for a bit more than a year, it came crashing down.

The crash made it all too clear that mathematics, once my refuge, was not only deeply entangled in the world’s problems, but also fueling many of them. The housing crisis, the collapse of major financial institutions, the rise of unemployment — all aided and abetted by mathematicians wielding magic formulas. What’s more, thanks to the extraordinary powers I loved so much, math combined with technology to multiply the chaos and misfortune, adding efficiency and scale to systems that I now recognized as flawed.

If we had been clear-headed, we all would have taken a step back to figure out how math had been misused and how we could prevent a similar catastrophe in the future. But instead, in the wake of the crisis, new mathematical techniques were hotter than ever, and expanding into still more domains. They churned 24/7 through petabytes of information, much of it scraped from social media or e-commerce websites. And increasingly, they focused not on the movements of global financial markets but on human beings — on us. Mathematicians and statisticians were studying our desires, movements and spending power. They were predicting our trustworthiness and calculating our potential as students, workers, lovers, criminals.


Discovery Magazine: Weapons of Math Destruction, Cathy O'Neill

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IoT and Security...

Posted by Reginald L. Goodwin on November 3, 2016 at 6:25am
Credit: Courtesy of BRAND X PICTURES


Topics: Computer Science, Consumer Electronics, Internet, Internet of Things


As someone who saw DARPANET evolve from a simple text only communication, to its first commercial applications in AOL,  Netscape to now, I've been a little worried that such gadgets would only give a pathway to hackers into our homes. One likely and sad scenario could be (out of spite and pure evil), some sociopath with a keyboard could set your thermostat to 100 degrees, whether or not realizing you have pets that could be compromised under such conditions the hours you're away from them at work. Not trying to depress holiday sales, but we really need to think this one through before the inevitable flurry of patches that will be pushed out in response to attacks.

With this year’s approaching holiday gift season the rapidly growing “Internet of Things” or IoT—which was exploited to help shut down parts of the Web this past Friday—is about to get a lot bigger, and fast. Christmas and Hanukkah wish lists are sure to be filled with smartwatches, fitness trackers, home-monitoring cameras and other wi-fi–connected gadgets that connect to the internet to upload photos, videos and workout details to the cloud. Unfortunately these devices are also vulnerable to viruses and other malicious software (malware) that can be used to turn them into virtual weapons without their owners’ consent or knowledge.

Last week’s distributed denial of service (DDoS) attacks—in which tens of millions of hacked devices were exploited to jam and take down internet computer servers—is an ominous sign for the Internet of Things. A DDoS is a cyber attack in which large numbers of devices are programmed to request access to the same Web site at the same time, creating data traffic bottlenecks that cut off access to the site. In this case the still-unknown attackers used malware known as “Mirai” to hack into devices whose passwords they could guess, because the owners either could not or did not change the devices’ default passwords.

The IoT is a vast and growing virtual universe that includes automobiles, medical devices, industrial systems and a growing number of consumer electronics devices. These include video game consoles, smart speakers such as the Amazon Echo and connected thermostats like the Nest, not to mention the smart home hubs and network routers that connect those devices to the internet and one another. Technology items have accounted for more than 73 percent of holiday gift spending in the U.S. each year for the past 15 years, according to the Consumer Technology Association. This year the CTA expects about 170 million people to buy presents that contribute to the IoT, and research and consulting firm Gartner predicts these networks will grow to encompass 50 billion devices worldwide by 2020. With Black Friday less than one month away it is unlikely makers of these devices will be able to patch the security flaws that opened the door to last week’s attack.

Scientific American: IoT Growing Faster Than the Ability to Defend It
Larry Greenemeier

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3D Acoustic Holograms...

Posted by Reginald L. Goodwin on November 3, 2016 at 6:22am
The researchers designed a hologram that projects sound waves with an amplitude pattern shaped like the letter "A". The top images show the simulated field patterns of the amplitude of sound waves at three representative depths. The bottom row shows the actual experimental amplitudes recorded in an anechoic chamber. (Courtesy: Scientific Reports 6 35437)

Topics: Acoustic Physics, Electromagnetism, Holograms, Metamaterials

Researchers in the US have created a printed array of metamaterials that can produce passive 3D acoustic holograms from a simple sound source, such as a single speaker. The device is made up of 3D-printed Lego-like blocks that can be put together in different configurations. The researchers say that their method is cheaper and simpler than other techniques and that they expect it to "open a new realm of holographic acoustic wave manipulation".

A visual hologram manipulates electromagnetic waves in the visible part of the spectrum to create a 3D image. Because sound also travels in waves, it should be possible to create complex 3D fields of sound – acoustic holograms – in a similar way. While visual holograms can be made with physical structures that diffract light, it isn't so easy with sound due to a lack of materials with the required acoustic properties. Generally, acoustic holograms use a transducer array controlled by complex phase shifting electronics.

Physics World: Building-block metamaterials shape 3D acoustic holograms
Michael Allen is a science writer based in Bristol, UK
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Proxima Centauri b...

Posted by Reginald L. Goodwin on November 1, 2016 at 5:42am
Breakthrough Starshot concept would use a giant Earth-based laser array to accelerate a space sail to a significant fraction of the speed of light. Destination: Proxima Centauri b? (Credit: Breakthrough Initiatives)
Image Source: Astronomy Magazine


Topics: Astronomy, Astrophysics, Exoplanets, Solar Sail, Space Exploration


The hunt for exoplanets has, in some ways, been about the hunt for an Earth-like planet - something warm where water could exist. Headlines tout each discovery as "the most Earth-like planet yet." Many of these planets are far away.

But a new discovery published August 24 in Nature hits closer to home, with an Earth-like planet in the habitable zone of a star. Whats more, that star is Proxima Centauri, only 4.24 light-years away. That means that there is no solar system that will be closer to Earth in our lifetimes.

And so far, the exoplanet, named Proxima Centauri b, is shaping up to be quite Earth-like, roughly the mass of our planet and in just the right place where, if it has an atmosphere, liquid water could exist on the surface.

This is as in our backyard as it gets.

Astronomy: The exoplanet next door
John Wenz is an associate editor at Astronomy magazine

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Happy Hallowing...

Posted by Reginald L. Goodwin on October 31, 2016 at 5:00am
Mutant flies are scary things, as victims of The Fly can attest. Happy Hallowing!
20th Century Fox/The Kobal Collection at Art Resource, NY


Topics: Biology, Humor, Nobel Laureate, Nobel Prize, Science Fiction


During the whole of a dull, dark, and soundless day in the autumn of the year, when the clouds hung oppressively low in the heavens and the shades of evening drew on, a sense of insufferable gloom fell on geneticist Michael O’Connor. He was looking at decaying embryos of fruit flies in his lab that had mutations in genes known as disembodiment and ghost, mummy and haunted, shroud and phantom, spook and shadow. There was an iciness, a sinking, a sickening of the heart—an unredeemed dreariness of thought which no goading of the imagination could torture into aught of the sublime, when it came to him with a power that lies beyond our depth. “These are Halloween genes!” he declared, trembling at the realization that he had coined a catchy scientific phrase. And from that shadowy day forward in the late 1990s, so they have been known far and wide.

OK, that’s not exactly what happened, and apologies to Edgar Allan Poe. But O’Connor, who heads the genetics department at the University of Minnesota in Minneapolis did dub disembodiment, ghost, and their creepy, ghoulish kin “Halloween genes.” In what became an iconic image—in his lab at least—one of the postdocs, Marcela Chavez, drew a fly on a witch’s broom. A native Spanish speaker, Chavez remembers cracking everyone up at one lab meeting when a misspelling in her presentation read “Hallowing” genes.

The identification and naming of the genes themselves came out of a massive screen for mutants in the fly embryonic genome that led to the Nobel Prize in 1995. One of the winners, Ed Lewis, was a friend of O’Connor’s. “Ed was a big Halloween person,” O’Connor says. “He’d spend all year making his Halloween costumes.” A fan of Belgian surrealist René Magritte, Lewis would dress as characters from his paintings, including the man in a leopard print caveman garb holding a barbell in Perpetual Motion and the man with a birdcage chest and straw hat in The Therapist.

Science: A gory tale behind the origin of ‘Halloween genes’, Jon Cohen

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Stillness...

Posted by Reginald L. Goodwin on October 28, 2016 at 4:44am
Alien robot Gort from The Day the Earth Stood Still


Topics: Astrobiology, Astronomy, Existentialism, Exoplanets, Politics, SETI


"Gort" is the robot above from the 1951 movie "The Day the Earth Stood Still." We've been fascinated as a species by the visitation of gods, goblins, demons, fairies and off-world entities since I can remember. "Chariots of the Gods" was a bestseller until the science by its author was proven speculative farce. Erich von Däniken has managed to live on on the History 2 channel: "Ancient Aliens," which is always the only conclusion so much so it like the historian with the frizzy hairdo is cliche.

Even our popular comic fiction speculates on the weirdness such an encounter would be; mind and societal-altering. In the fictional Marvel world of The Avengers, their advent is known to the non-powered humans as "the incident" in disturbing, ominous tones. The thought of being surrounded by super powered beings wouldn't likely be reassuring as they were in the 50's and 60's. What if instead of being benevolent do-gooders, they imposed a fascist order with martial law? What indeed would stop them? Thankfully, it's all wildly speculative fiction from the fertile minds of us mere mortals.



For those of us who believe in Close Encounters of the Third and Fourth Kind (contact, abduction): 1. What makes our planet in parsecs of other candidates so special? 2. If they are that advanced, we're kind of like worms or piglets in a biology class - if it's happening, that's more than a bit disturbing.

Even if we got a chance radio transmission following up the "WOW" signal, we probably couldn't stop talking about it. And if the aliens were to actually pay us a visit, our self-concept would be jolted; holy writ would be reexamined to see how the existence of intelligence obviously beyond us on our "0.7 Kardashev Scale" would make us feel puny and...threatened.

Still, 13.6 billion years is a long time and a lot of still, silent space to be alone in. I think I prefer to think (and hope) someone else is out there. That's a lot of real estate to go extinct in by our own hubris - climate or nuclear, and if we did the point of existence - our discoveries, literature, art, music theater, dance, and languages - would have been sadly moot.

In Preparing for Contact George Michael has given us a tour de force exploration of the thinking, issues, and dilemmas surrounding the search for extraterrestrial life in the universe.

Those familiar with Professor Michael’s other books and articles—on a wide variety of critical topics including politics, nuclear proliferation, science, and terrorism—know that he conducts rigorous research and major scholarly inventories before completing a manuscript. Preparing for Contact clearly represents years of thinking and research on the subject. Michael’s approach is meticulous, objective, and fearless in examining every relevant aspect—historical, current, and futuristic—of the alien civilization question. The book dives into fundamental questions. First, what have been the scientific (or otherwise) endeavors to consider if intelligent life might exist elsewhere in the universe? Second, if we do make contact with an alien civilization, how should we respond, and what might be the larger implications for our civilization

Preparing for Contact has a logical chapter progression. From early speculation about extraterrestrial life, including Egyptian, Roman, Hindu, and Central American civilizations’ speculations to the recent findings of astrobiology and astronomy, to the UFO phenomenon, and the SETI (Search for Extraterrestrial Intelligence) project, Michael proceeds in systematic fashion. Regarding possible life on Mars, for example, the Swiss author Erich von Däniken’s wildly popular book, Chariots of the Gods, became a US television film. However, its assumptions of alien life on Mars were disproven after successive probes of Mars found only natural structures, not artificial ones. Additional space probes make us confident that we are the only intelligent life in this solar system. But what about farther out in the Milky Way galaxy, among the thousands of exoplanets which are being discovered at a rate of about two a week?

Skeptic: Meeting ET, Lawrence E. Grinter

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Magnetic Monopoles...

Posted by Reginald L. Goodwin on October 27, 2016 at 6:45am
HEIKKA VALJA/MoEDAL COLLABORATION
Citation: Phys. Today 69, 10, 40 (2016); http://dx.doi.org/10.1063/PT.3.3328


Topics: Electromagnetism, James Clerk Maxwell, Materials Science


The discovery of the mysterious hypothetical particles would provide a tantalizing glimpse of new laws of nature beyond the standard model.

Electricity and magnetism appear everywhere in the modern world and form the basis of most of our technology. Therefore, it would be natural to assume that they are already fully understood and no longer pose unanswered fundamental physics questions. Indeed, for most practical purposes they are perfectly well described by classical electrodynamics, as formulated by James Clerk Maxwell in 1864. At a deeper level, a consistent quantum mechanical account is given by quantum electrodynamics, part of the standard model of particle physics. The theory works so well that it predicts the magnetic dipole moment of the electron accurately to 10 significant figures. Nevertheless, there is still an elementary aspect of electromagnetism that we do not understand: the question of magnetic monopoles.1

That magnets always have two poles—north and south—seems like an obvious empirical fact. Yet we do not know any theoretical reason why magnetic monopoles, magnets with a single north or south pole, could not exist. Are we still missing some crucial fundamental aspect of the theory? Or do magnetic monopoles exist and we simply have not managed to find them yet?

Nothing in classical electrodynamics prohibits magnetic monopoles; in fact, they would make the theory more symmetric. As Maxwell noted, the laws governing electricity and magnetism are identical. That can be seen in the Maxwell equations of electrodynamics, which in vacuum have a duality symmetry—the electric terms can be replaced with magnetic terms, and vice versa, in such a way that the equations are left unchanged. That symmetry is broken only in the presence of electric charges and currents, which have no magnetic counterparts. If magnetic monopoles existed, they would carry the magnetic equivalent of an electric charge, and they would restore the duality symmetry (see figure 1). On aesthetic grounds, one would therefore expect their existence.

Physics Today: The search for magnetic monopoles, Arttu Rajantie

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Neutron Holography...

Posted by Reginald L. Goodwin on October 26, 2016 at 6:02am
Interference pattern created by neutron holography.
Credit: NIST


Topics: Holograms, Neutrons, NIST, Research


For the first time, a team including scientists from the National Institute of Standards and Technology (NIST) have used neutron beams to create holograms of large solid objects, revealing details about their interiors in ways that ordinary laser light-based visual holograms cannot.

Holograms—flat images that change depending on the viewer’s perspective, giving the sense that they are three-dimensional objects—owe their striking capability to what’s called an interference pattern. All matter, such as neutrons and photons of light, has the ability to act like rippling waves with peaks and valleys. Like a water wave hitting a gap between the two rocks, a wave can split up and then re-combine to create information-rich interference patterns.

An optical hologram is made by shining a laser at an object. Instead of merely photographing the light reflected from the object, a hologram is formed by recording how the reflected laser light waves interfere with each other. The resulting patterns, based on the waves’ phase differences (link is external), or relative positions of their peaks and valleys, contain far more information about an object’s appearance than a simple photo does, though they don’t generally tell us much about its hidden interior.

Hidden interiors, however, are just what neutron scientists explore. Neutrons are great at penetrating metals and many other solid things, making neutron beams useful for scientists who create a new substance and want to investigate its properties. But neutrons have limitations, too. They aren’t very good for creating visual images; neutron experiment data is usually expressed as graphs that would look at home in a high school algebra textbook. And this data typically tells them about how a substance is made on average—fine if they want to know broadly about an object built from a bunch of repeating structures like a crystal (link is external), but not so good if they want to know the details about one specific bit of it.

But what if we could have the best of both worlds? The research team has found a way.

NIST:
Move Over, Lasers: Scientists Can Now Create Holograms from Neutrons, Too
Chad T. Boutin

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Graphene and Green Cars...

Posted by Reginald L. Goodwin on October 25, 2016 at 6:00am
Simulations by Rice University scientists show that pillared graphene boron nitride may be a suitable storage medium for hydrogen-powered vehicles. Above, the pink (boron) and blue (nitrogen) pillars serve as spacers for carbon graphene sheets (gray). The researchers showed the material worked best when doped with oxygen atoms (red), which enhanced its ability to adsorb and desorb hydrogen (white). Credit: Lei Tao/Rice University


Topics: Climate Change, Graphene, Green Tech, Nanotechnology


Layers of graphene separated by nanotube pillars of boron nitride may be a suitable material to store hydrogen fuel in cars, according to Rice University scientists.

The Department of Energy has set benchmarks for storage materials that would make hydrogen a practical fuel for light-duty vehicles. The Rice lab of materials scientist Rouzbeh Shahsavari determined in a new computational study that pillared boron nitride and graphene could be a candidate.

The study by Shahsavari and Farzaneh Shayeganfar appears in the American Chemical Society journal Langmuir.

Shahsavari's lab had already determined through computer models how tough and resilient pillared graphene structures would be, and later worked boron nitride nanotubes into the mix to model a unique three-dimensional architecture. (Samples of boron nitride nanotubes seamlessly bonded to graphene have been made.)

Just as pillars in a building make space between floors for people, pillars in boron nitride graphene make space for hydrogen atoms. The challenge is to make them enter and stay in sufficient numbers and exit upon demand.

Phys.org: Scientists say boron nitride-graphene hybrid may be right for next-gen green cars

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