The behavior of so-called “strange metals” has long puzzled scientists—but a group of researchers at the University of Toronto may be one step closer to understanding these materials.
Electrons are discrete, subatomic particles that flow through wires like molecules of water flowing through a pipe. The flow is known as electricity, and it is harnessed to power and control everything from lightbulbs to the Large Hadron Collider.
In quantum matter, by contrast, electrons don’t behave as they do in normal materials. They are much stronger, and the four fundamental properties of electrons—charge, spin, orbit, and lattice—become intertwined, resulting in complex states of matter.
“In quantum matter, electrons shed their particle-like character and exhibit strange collective behavior,” says condensed matter physicist Arun Paramekanti, a professor in the U of T’s Department of Physics in the Faculty of Arts & Science. “These materials are known as non-Fermi liquids, in which the simple rules break down.”
Now, three researchers from the university’s Department of Physics and Centre for Quantum Information & Quantum Control (CQIQC) have developed a theoretical model describing the interactions between subatomic particles in non-Fermi liquids. The framework expands on existing models and will help researchers understand the behavior of these “strange metals.”
Their research was published in the journal Proceedings of the National Academy of Sciences (PNAS). The lead author is physics Ph.D. student Andrew Hardy, with co-authors Paramekanti and post-doctoral researcher Arijit Haldar.
“We know that the flow of a complex fluid like blood through arteries is much harder to understand than water through pipes,” says Paramekanti. “Similarly, the flow of electrons in non-Fermi liquids is much harder to study than that in simple metals.”
Hardy adds, “What we’ve done is construct a model, a tool, to study non-Fermi liquid behavior. And specifically, to deal with what happens when there is symmetry breaking, when there is a phase transition into a new type of system.”
“Symmetry breaking” is the term used to describe a fundamental process found in all of nature. Symmetry breaks when a system—whether a droplet of water or the entire universe—loses its symmetry and homogeneity and becomes more complex.
Tech Target (Alyssa Provazza, Editorial Director): “A smartphone is a cellular telephone with an integrated computer and other features not originally associated with telephones, such as an operating system, web browsing, and the ability to run software applications.” Smartphones, however, have had a detrimental effect on humans regarding health, critical thinking, and cognitive skills, convenient though they are.
I’ve seen the idea of “smart guns” for decades. Like the fingerprint scan for biometric safes, it’s a safeguard that some will opt for but most likely won’t unless compelled by legislation, which in the current “thoughts and prayers” environment (i.e., sloganeering is easier than proposing a law if you continually get away with it), I’m not holding my breath. A recent, late 20th Century example:
In 1974, the federal government passed the National Maximum Speed Law, which restricted the maximum permissible vehicle speed limit to 55 miles per hour (mph) on all interstate roads in the United States.1 The law was a response to the 1973 oil embargo, and its intent was to reduce fuel consumption. In the year after the National Maximum Speed Law was enacted, road fatalities declined 16.4%, from 54,052 in 1973 to 45,196 in 1974.2
In April of 1987, Congress passed the Surface Transportation and Uniform Relocation Assistance Act, which permitted states to raise the legal speed limit on rural interstates to 65 mph.3 Under this legislation, 41 states raised their posted speed limits to 65 mph on segments of rural interstates. On November 28, 1995, Congress passed the National Highway Designation Act, which officially removed all federal speed limit controls. Since 1995, all US states have raised their posted speed limits on rural interstates; many have also raised the posted speed limits on urban interstates and non interstate roads.
Conclusions.Reduced speed limits and improved enforcement with speed camera networks could immediately reduce speeds and save lives, in addition to reducing gas consumption, cutting emissions of air pollutants, saving valuable years of productivity, and reducing the cost of motor vehicle crashes.
Homo Sapiens, (Latin) “wise men,” don’t always do smart things.
In an office parking lot about halfway between Denver and Boulder, a former 50-foot-long shipping container has been converted into a cramped indoor shooting range. Paper targets with torsos printed on them hang from two parallel tracks, and a rubber trap waits at the back of the container to catch the spent bullets. Black acoustic foam padding on the walls softens the gunshot noise to make the experience more bearable for the shooter, while an air filtration system sucks particulates out of the air. It’s a far cry from the gleaming labs of the average James Bond movie, but Q might still be proud.
The weapons being tested at this site are smart guns: They can identify their registered users and won’t fire [for] anyone else. Smart guns have been a notoriously quixotic category for decades. The weapons carry the hope that an extra technological safeguard might prevent a wide range of gun-related accidents and deaths. But making a smart gun that’s good enough to be taken seriously has proved beyond difficult. It’s rare to find engineers with a strong understanding of both ballistics and biometrics whose products can be expected to work perfectly in life-or-death situations.
Some recent attempts have amounted to little more than a sensor or two slapped onto an existing weapon. More promising products have required too many steps and taken too much time to fire compared with the speed of a conventional handgun. What separates the Biofire Smart Gun here in the converted shipping container is that its ID systems, which scan fingerprints and faces, have been thoroughly melded into the firing mechanism. The battery-powered weapon has the sophistication of high-end consumer electronics, but it’s still a gun at its core.
The graph is part of an exercise that I do after every shooting. If you’ve got a stock app on your smartphone, it’s easy to track. There is an uptick in any stock that trades with gun manufacturers. It was simple to blame it on the fear of gun control that never materializes, despite the massacres’ gruesomeness or the victims’ innocence. It turns out that terrorizing citizens is public policy. When you get beyond the reflexive “thoughts and prayers,” what do you have left other than the obvious? Terrorized citizens can’t think clearly, don’t read leisurely fiction or historical record, or absorb civics or critical thinking. Voltaire warned about tyranny, but the threat of assassination seems to be as tyrannical as the Kremlin. Putin has eleven time zones, terrified by everybody dropped from a window, every dissident imprisoned in a gulag, or every ex-pat poisoned in another country. America is dangerous to our health inside and outside our homes (see: Breonna Taylor). Where do we go in public that cannot become a crime scene?
It turns out that my “Stop the Bleeding” kit arrived after Easter instead of before, delayed by the likely deluge of other orders from my active shooter class and others around the nation that decided the 55th anniversary of the assassination of Dr. King was a GREAT day to do a class! A taser I ordered for my wife came in from Amazon on the same day.
After Tennessee, on April 11, 2023, America had another mass shooting in Louisville, Kentucky. The governor of that state lost two friends, and a third at the time was in critical condition. Five people were killed, and about nine were injured.
April 13, 2023, a 35-year-old English teacher was killed by a lone gunman in the drive-through of a Dunkin Donuts in Philadelphia, Pennsylvania. Her eleven-year-old son was unharmed in the backseat, but he saw his mother executed for no reason. His psyche, regarding harm, is another matter. Mother’s Day is next month, and I don’t think the cliché “thoughts and prayers” will cut it.
I now carry pepper spray on my keychain. I have a telescoping baton that makes a metallic “shooshing” sound, a hopeful shock to an assailant. In addition to pepper spray and a taser, I plan to give my wife my 9mm pistol (hopefully without the same glitches as Sig Sauer pistols, shooting when not hitting the trigger) and a purse that will double as a holster: if threatened, she’ll have to shoot through it. We didn’t leave Afghanistan: we brought the war home.
*****
“Jonny Quest” is one of the many cartoons I’ve taken to collecting on DVD. I bought a DVD player that looks like a laptop but only has the drive, screen, controls, and remote. Jonny Quest was about the adventures of Jonny, his friend from Calcutta, Haji, his dog, who looked like a pug mutt, “Race” Bannon (that’s how his name was listed). And Dr. Benton Quest, who had as much of an impact as “The Undersea World of Jacques Cousteau” and “Marlin Perkins’ ‘Wild Kingdom.’” The STEM focus of the latter is self-evident. Dr. Benton Quest was a biologist on one Saturday, a physicist on the next Saturday, a Chemist, or an Electrical Engineer on any given Saturday where the situation needed him to be! There were car chases, a Cyclops, spider legged robot spy, dog fights with a Nazi, and LOTS of guns! Dr. Quest was the epitome of a nanotechnologist*, years after Dr. Richard Feynman’s lecture “There’s Plenty of Room at the Bottom” circa 1959 and years before Dr. Norio Taniguchi coined it at a conference in Japan in 1974. Thankfully, neither Jonny nor Haji were involved in gunplay.
“Jonny Quest” is utter fantasy, a cartoon. All of us kids were in on the “gag.” Only the “evil-doers” died, never us “good guys.”
I feel like we’re going to war every day instead of work.
What kind of country or cartoon is this?
*****
*My “elevator pitch” definition:
Nanotechnology regards biology, chemistry, engineering, mathematics, and physics, all of the major STEM disciplines at the nanoscale. Nano means “billionth,” or 10-9 meters. Nanoscience is the theoretical observation of nanoscale phenomena. Nanoengineering is exploiting that phenomenon towards a practical (engineering) end, as in manufacturing something that can be purchased or consumed. Before I entered the field, Dr. Quest was probably the first nanotechnologist I had ever seen and didn’t recognize because the definition wasn’t as ubiquitous as it is now.
Topics: Battery, Chemistry, Climate Change, Economics, Global Warming
Welcome back to The Green Era, a weekly newsletter bringing you the news and trends in the world of sustainability. Click subscribe above to be notified of future editions.
The shift to renewable energy has caused consternation over the fate of workers in the fossil fuel industry. Those same concerns are hitting the automotive sector as U.S. demand for electric vehicles grows.
EVs require not just new assembly lines and parts but also factories to build the batteries that power them. The president of one of the biggest unions called the transition the largest in the industry’s history.
The automotive sector and its workers are not new to factory closures. The Great Recession brought the big three automakers to their knees, forcing the federal government to bail them out, leaving cities like Detroit and large swaths of the midwest with car workers out of a job.
This time could be different. Many factories are being converted and are investing in retraining their workers. The batteries and charging infrastructure required present another opportunity. Ford, General Motors, and Volkswagen are all building new battery manufacturing plants or expanding existing ones in Tennessee.
In an advance, they consider a breakthrough in computational chemistry research. University of Wisconsin–Madison chemical engineers have developed a model of how catalytic reactions work at the atomic scale. This understanding could allow engineers and chemists to develop more efficient catalysts and tune industrial processes—potentially with enormous energy savings, given that 90% of the products we encounter in our lives are produced, at least partially, via catalysis.
Catalyst materials accelerate chemical reactions without undergoing changes themselves. They are critical for refining petroleum products and for manufacturing pharmaceuticals, plastics, food additives, fertilizers, green fuels, industrial chemicals, and much more.
Scientists and engineers have spent decades fine-tuning catalytic reactions—yet because it’s currently impossible to directly observe those reactions at the extreme temperatures and pressures often involved in industrial-scale catalysis, they haven’t known exactly what is taking place on the nano and atomic scales. This new research helps unravel that mystery with potentially major ramifications for the industry.
In fact, just three catalytic reactions—steam-methane reforming to produce hydrogen, ammonia synthesis to produce fertilizer, and methanol synthesis—use close to 10% of the world’s energy.
“If you decrease the temperatures at which you have to run these reactions by only a few degrees, there will be an enormous decrease in the energy demand that we face as humanity today,” says Manos Mavrikakis, a professor of chemical and biological engineering at UW–Madison who led the research. “By decreasing the energy needed to run all these processes, you are also decreasing their environmental footprint.”
Topics: African Americans, Civics, Civil Rights, Civilization, Climate Change, Democracy, Diversity in Science, Environment, Existentialism, Fascism, Global Warming, Human Rights
April is National Poetry Month. This photo of five-year-old me inspired my haiku about my kindergarten graduation. It should have been a happy day with parents in the audience.
Dr. Martin Luther King Jr. was assassinated on Thursday, April 4, 1968. Our graduation was scheduled for that Friday at Bethlehem Community Center in Winston-Salem, North Carolina.
All thirty-six students were blissfully unaware of the political earthquake that this was or that it had occurred. As we all aged, we probably learned of the death threats and the near assassination by a deranged woman at a book signing. We were unaware of the “Missiles of October” in 1962, barely scratching the planet’s surface or taking our first steps before potential Armageddon. Medgar Evers was assassinated in Mississippi in June of 1963, and President John F. Kennedy was assassinated in November of the same year in Dallas when we were a little over a year old. Brother Malcolm was assassinated in February 1965 when we were almost three. I don’t recall the University of Texas. Clock Tower shooting in 1966, but we were four then. My classmates, like me, probably heard a program on the local radio station, WAAA-AM, on Sundays from the Southern Christian Leadership Conference, “Martin Luther King Speaks.” At that time, the caveat was that he spoke, addressing his audience directly over AM, the complete analog of today’s social media. What are now tapes or YouTube videos for later generations: it was him, alive, breathing, and speaking. Then Robert F. Kennedy, June 6, the president’s brother running for president, fell that year.
I recall my mother kissing me profusely, promising to be there for the graduation, and saying “I love you” repeatedly. I had no doubts about that.
I also remember my father’s eyes: red with bloodshot, dried tears on his cheeks. To that point in my brief existence, the thought of him crying was alien, foreign.
The kindergarten teachers sat us down. We assumed to prepare us for the costumes we would wear – white shorts, shirts, and bow ties for the boys, and skirts for the girls.
“Children, Dr. Martin Luther King was shot yesterday and died.”
Stunned silence.
I am on the front row, the photo’s first student on the left. The eighth student on that row is a girl who I recall having a crush on: she has her right knee pointing towards her left leg. She would break the silence before our ceremony with an ear-piercing screech, repetitive, inconsolable grief beyond her years, perhaps mimicked from a funeral. We all knew what “died” meant. In some form or fashion, by five, you have lost beloved pets or relatives that you never thought would leave the Earth.
The seed from her grief cascaded through the graduates like a malignant vine. The time was 9:00. We cried for two hours, during which someone with a pickup truck, a rebel flag flying, drove through the parking lot, yelling over and over so our young ears and teachers could hear him, “Martin Luther Coon’s dead! Yahoo! The South will rise again!”
I lay on the linoleum, palm heels in my eye sockets, wailing my [own] notes. The teachers were crying with us, trying to console themselves and us, allowing us our grief. We went down for a nap at 11:00. Perhaps our teachers did too.
We went out for a brief recess, probably to clear the fog from our brains, but as I recall, we moved like zombies, with no one on the seesaw, children sitting, staring numbly on the swings, and no action on the monkey bars. Then we went in and got dressed.
Our parents would be there at 1:30 pm. I have described why not a single child graduating in the photo was smiling. Staring at my unsmiling, well, forced smiling parents, I remember this poignant thought post-grief beyond my brief years:
“We’re not kids anymore!”
We would all start first grade in the fall without him.
I hugged my big sister tightly that evening, a student activist in the Civil Rights Movement attending Winston-Salem State University, because I knew, without a shadow of a doubt, what “died” meant.
My employer hosted an Active Shooter/Stop the Bleeding training at my facility on probably the most insensitive date they could pick on the calendar: the 55th anniversary of the assassination of Dr. King. As the first haiku eludes, time does not heal trauma. For the first half, both instructors had experience in law enforcement and the military. The second set of three instructors from a local trauma center featured a combat medic, who taught us through a cadaver dummy to stuff gauze from a “stop the bleeding kit” (there is a website to order directly).
I participated in the class vigorously to fight the “sugar crash” from the doughnuts offered.
We saw a lot of videos, one featuring the shooter in the Naval Shipyards gun massacre. The other was the bodycam video from the recent incident in Tennessee at a Christian School where three adults in their early sixties (around my same age) and three nine-year-old children were sacrificed on the altar of American Moloch. The original intent of particularly white evangelical Christian schools was to protect the “innocence” of their children from sitting next to someone like me. Somehow “thoughts and prayers” for a Christian school, no doubt inspired by Brown vs. Board of Education being actualized in the South, seemed oxymoronic.
“Duck-and-hide,” or more accurately, duck-and-cover, where drills were part of civilian preparedness in the event World War Three spontaneously broke out. They gave us manuals we should read (I still have mine). The teachers and manual said that getting under the desk was the best way to survive the nuclear fallout if you were not the center of the blast radius. Preconscious and curious, my parents had bought the complete volumes of the Encyclopedia Britannica, the Internet of its day. Foreshadowing my eventual STEM majors in Engineering Physics, Microelectronics, and Nanoengineering, I read the “Nu” volume on nuclear weapons. I sadly concluded after my research that the drills were government-sanctioned gaslighting, a word I now use. The word I used then is a two-syllable word with the popular abbreviation “B.S.” Plutonium 239, the ore of choice for thermonuclear weapons, has a half-life of 24,100 years, meaning that it would be half as radioactive in about 24 millennia. This drill wasn’t to save lives but to reduce panicked stampeding that, I admit, would help no one. The official nuclear doctrine of deterrence is M.A.D.: mutually assured destruction. We’ll see if Russia in Ukraine remembers this at all.
The United States has been in some war 93% of the time from 1775 (before its existence) to 2018. This factum is according to Smithsonian Magazine. The article’s caveat is how to interpret “war”: declared congressionally, unilaterally by the executive, or (in my opinion) upon one’s citizens.
I will attend my precocious granddaughter’s fourth birthday party this National Poetry Month. She is one year younger than my five-year-old image. After getting her a “Dr. McStuffin’s Medical Kit” for Christmas, she immediately assigned herself as her grandparents’ doctor. She even does televisits when we chat on Google Hangout.
Yet she grows up in a world of the continuous threat of Armageddon. Add to that designed scarcity, economic Disaster Capitalism cum neoliberalism, rising global temperatures, and active shooter training when she starts kindergarten in the fall, minus the “stop the bleeding kits,” even with her Dr. McStuffin credentials. Because of the malaise of government and gun lobbyists, we’ve reduced her citizenry to becoming a combat medic in the future, whether she wants to or not.
I bought a “stop the bleeding” kit. It should be here before Easter.
Researchers detected a surprising rise in levels of chlorofluorocarbons between 2010 and 2020 using a monitoring network that includes the Jungfraujoch research station in Switzerland. Credit: Shutterstock
Topics: Chemistry, Civilization, Climate Change, Environment, Global Warming
From my resume: “I eliminated ozone-depleting materials using Failure Mode and Effects Analysis (FMEA) and Taguchi Methods of Quality Engineering – using an L16 Orthogonal Array – in the Poly Silicon etch processes substituting out CFCs in manufacturing processes.” How I did it: I substituted our CFC with Sulfur Hexafluoride and Nitrogen (SF6/N2). On the negative photoresist product, the CFC over-etch was 50 seconds. For the positive photoresist, CFC had a 25-second process. I was able to reduce each product line to two seconds, increasing throughput, and the process increased die yields. It is possible to balance the positive impact of product improvement and the environment. I did it in the 90s, so the following report is disappointing.
*****
The Montreal Protocol, which banned most uses of ozone-destroying chemicals known as chlorofluorocarbons (CFCs) and called for their global phase-out by 2010, has been a great success story: Earth’s ozone layer is projected to recover by the 2060s.
So atmospheric chemists were surprised to see a troubling signal in recent data. They found that the levels of five CFCs rose rapidly in the atmosphere from 2010 to 2020. Their results are published today in Nature Geoscience1.
“This shouldn’t be happening,” says Martin Vollmer, an atmospheric chemist at the Swiss Federal Laboratories for Materials Science and Technology in Dübendorf, who helped to analyze data from an international network of CFC monitors. “We expect the opposite trend. We expect them to slowly go down.”
At current levels, these CFCs do not pose much threat to the ozone layer’s healing, said Luke Western, a chemist at the University of Bristol, UK, at an online press conference on 30 March. CFCs, once used as refrigerants and aerosols, can persist in the atmosphere for hundreds of years. Given that they are potent greenhouse gases, eliminating emissions of these CFCs will also have a positive impact on Earth’s climate. The collective annual warming effect of these five chemicals on the planet is equivalent to the emissions produced by a small country like Switzerland.
It’s highly likely that manufacturing plants are accidentally releasing three of the chemicals — CFC-113a, CFC-114a, and CFC-115 — while producing replacements for CFCs. When CFCs were phased out, hydrofluorocarbons (HFCs) were brought in as substitutes. But CFCs can crop up as unintended by-products during HFC manufacture. This accidental production is discouraged by the Montreal Protocol but not prohibited by it.
The classic double-slit experiment leads to characteristic interference patterns. Credit: Russell Knightly/SPL
Topics: Modern Physics, Optics, Quantum Mechanics
A celebrated experiment in 1801 showed that light passing through two thin slits interferes with itself, forming a characteristic striped pattern on the wall behind. Now, physicists have shown that a similar effect can arise with two slits in time rather than space: a single mirror that rapidly turns on and off causes interference in a laser pulse, making it change color.
The result is reported on 3 April in Nature Physics1. It adds a new twist to the classic double-slit experiment performed by physicist Thomas Young, which demonstrated the wavelike aspect of light, but also — in its many later reincarnations — that quantum objects ranging from photons to molecules have a dual nature of both particle and wave.
The rapid switching of the mirror — possibly taking just 1 femtosecond (one-quadrillionth of a second) — shows that certain materials can change their optical properties much faster than previously thought possible, says Andrea Alù, a physicist at the City University of New York. This could open new paths for building devices that handle information using light rather than electronic impulses.
Romain Tirole, a quantum physicist at Imperial College London, and his collaborators shot an infrared laser at a surface made of layers of gold and glass with a thin coating of indium tin oxide (ITO), a material common in smartphone screens.
Under normal conditions, ITO is transparent to infrared light. But the researchers were able to make the material reflective using a second laser, which excited electrons in the material, affecting its optical properties. This could be done with pulses from the second laser that lasted for around 200 femtoseconds.
The researchers positioned a light sensor along the reflected beam. When they shot two ultrashort pulses separated by a few tens of femtoseconds — therefore turning the ITO mirror on twice in rapid succession — they saw that the waveform of the twice-reflected light changed in response. It went from a simple, monochromatic wave to a more complex one.
The results also showed that the ITO took less than 10 femtoseconds to get excited — much faster than expected theoretically or from previous measurements. “The reason why everybody else thought it would be slower is that they used a different technique to measure the response time, which was limited to 50–100 fs,” says co-author Riccardo Sapienza, a physicist at Imperial College.
The Artemis 2 crew, from left to right: Jeremy Hansen, Reid Wiseman, Victor Glover, and Christina Koch. (NASA TV)
Topics: Astronautics, Astrophysics, International Space Station, NASA, Space Exploration
NASA has selected the four astronauts that will travel to the Moon during the upcoming Artemis 2 mission, which will be humanity’s first crewed return to the Moon in more than 50 years.
The four astronauts are Reid Wiseman, Victor Glover, and Christina Koch of NASA, and Jeremy Hansen of the Canadian Space Agency.
“The Artemis 2 crew represents thousands of people working tirelessly to bring us to the stars,” said NASA Administrator Bill Nelson before announcing the crew during a live event broadcast on NASA TV. “This is their crew. This is our crew. This is humanity’s crew.”
Spyware vendors are exploiting zero days and known vulnerabilities in Android, iOS, and Chrome, sparking an increase in “dangerous hacking tools,” warned Google’s Threat Analysis Group.
In a blog post on Wednesday, Clement Lecigne, a security engineer at Google, detailed two recent campaigns that TAG discovered to be “both limited and highly targeted.” The campaigns leveraged zero-day exploits alongside known vulnerabilities, or N days, against unpatched devices on widely used platforms.
In addition to emphasizing an ongoing patching problem, Google said the threat activity showed just how prevalent spyware vendors have become and the dangers they present, especially when wielding zero days.
“These campaigns are a reminder that the commercial spyware industry continues to thrive,” Lecigne wrote in the blog post.
TAG currently tracks more than 30 commercial surveillance vendors that sell exploits or spyware programs to various governments and nation-state threat groups. While Google acknowledged spyware use might be legal under national or international laws, such tools have historically been used against targets such as government officials, journalists, political dissidents, and human rights activists. For example, in 2018, NSO Group’s Pegasus spyware was linked to the death of journalist Jamal Khashoggi, who was killed by Saudi government agents in 2018 after being surveilled and tracked via his mobile phone.
While spyware has been used to track high-value targets in the past, Lecigne warned vendors that access to zero days and N days poses an even broader threat.
“Even smaller surveillance vendors have access to 0-days, and vendors stockpiling and using 0-day vulnerabilities in secret pose a severe risk to the internet,” Lecigne wrote. “These campaigns may also indicate that exploits and techniques are being shared between surveillance vendors, enabling the proliferation of dangerous hacking tools.”
Physics and Nano 