kbahey shares a report from Planet Princeton: Renowned mathematician and Princeton University professor John Horton Conway died April 11 as a result of complications from the coronavirus. He was 82. Conway made contributions to many areas of mathematics, including game theory, but was most well known for the invention of the cellular automaton called the Game of Life. The Guardian once called Conway the world's most charismatic mathematician. "John Horton Conway is a cross between Archimedes, Mick Jagger and Salvador Dali. For many years, he worried that his obsession with playing silly games was ruining his career -- until he realized that it could lead to extraordinary discoveries," wrote journalist Siobhan Roberts in a 2015 profile.

AmiMoJo shares a report from Nature: After an eight-year struggle, embattled Japanese mathematician Shinichi Mochizuki has finally received some validation. His 600-page proof of the abc conjecture, one of the biggest open problems in number theory, has been accepted for publication. Acceptance of the work in Publications of the Research Institute for Mathematical Sciences (RIMS) is the latest development in a long and acrimonious controversy over the mathematicians' proof. Mochizuki is chief editor but was not involved in the review.

Eight years ago, Mochizuki posted four massive papers online, claiming to have solved the abc conjecture. The work baffled mathematicians, who spent years trying to understand it. Then, in 2018, two highly respected mathematicians said they were confident that they had found a flaw in Mochizuki's proof -- something many saw as death blow to his claims. The "abc conjecture," the problem Mochizuki claims to have solved, expresses a profound link between the addition and multiplication of integer numbers. Any integer can be factored into prime numbers, its 'divisors': for example, 60 = 5 x 3 x 2 x 2. The conjecture roughly states that if a lot of small primes divide two numbers a and b, then only a few, large ones divide their sum, c. A proof, if confirmed, could change the face of number theory, by, for example, providing a novel approach to proving Fermat's last theorem, the legendary problem formulated by Pierre de Fermat in 1637 and solved only in 1995. Some experts say Mochizuki failed to fix the fatal flaw in the solution. "I think it is safe to say that there has not been much change in the community opinion since 2018," says Kiran Kedlaya, a number theorist at the University of California, San Diego.

Another mathematician, Edward Frenkel of the University of California, Berkeley, says, "I will withhold my judgment on the publication of this work until it actually happens, as new information might emerge."

BeerFartMoron writes: Recently there has been a proliferation of modeling work which has been used to make the point that if we can stay inside, practice extreme social distancing, and generally lock down nonessential parts of society for several months, then many deaths from COVID-19 can be prevented. But what happens after the lockdown? In an article studying the possible effects of heterogeneous measures, academics presented examples of epidemic trajectories for COVID-19 assuming no mitigations at all, or assuming extreme mitigations which are gradually lifted at 6 months, to resume normal levels at 1 year.

"Unfortunately, extreme mitigation efforts which end (even gradually) reduce the number of deaths only by 1% or so; as the mitigation efforts let up, we still see a full-scale epidemic, since almost none of the population has developed immunity to the virus," writes Wesley Pegden, Associate Professor, Department of Mathematical Sciences at Carnegie Mellon University. "There is a simple truth behind the problems with these modeling conclusions. The duration of containment efforts does not matter, if transmission rates return to normal when they end, and mortality rates have not improved. This is simply because as long as a large majority of the population remains uninfected, lifting containment measures will lead to an epidemic almost as large as would happen without having mitigations in place at all." "This is not to say that there are not good reasons to use mitigations as a delay tactic," Pegden adds. "For example, we may hope to use the months we buy with containment measures to improve hospital capacity, in the hopes of achieving a reduction in the mortality rate. We might even wish to use these months just to consider our options as a society and formulate a strategy."

"But mitigations themselves are not saving lives in these scenarios; instead, it is what we do with the time that gives us an opportunity to improve the outcome of the epidemic."

schwit1 shares a report from IEEE Spectrum: Here on Earth, our lives have been transformed by the Global Positioning System, fleets of satellites operated by the United States and other countries that are used in myriad ways to help people navigate. Down here, GPS is capable of pinpointing locations with accuracy measured in centimeters. Could it help astronauts on lunar voyages? Kar-Ming Cheung and Charles Lee of NASA's Jet Propulsion Laboratory in California did the math, and concluded that the answer is yes: Signals from existing global navigation satellites near the Earth could be used to guide astronauts in lunar orbit, 385,000 km away. The researchers presented their newest findings at the IEEE Aerospace Conference in Montana this month.

Cheung and Lee plotted the orbits of navigation satellites from the United States's Global Positioning System and two of its counterparts, Europe's Galileo and Russia's GLONASS system -- 81 satellites in all. Most of them have directional antennas transmitting toward Earth's surface, but their signals also radiate into space. Those signals, say the researchers, are strong enough to be read by spacecraft with fairly compact receivers near the moon. Cheung, Lee and their team calculated that a spacecraft in lunar orbit would be able to "see" between five and 13 satellites' signals at any given time -- enough to accurately determine its position in space to within 200 to 300 meters. In computer simulations, they were able to implement various methods for improving the accuracy substantially from there.

DevNull127 writes: MIT has a long-standing tradition. High school seniors who've been accepted into next year's class at MIT are informed on Pi Day (March 14th — that is, 3/14). And each year there's also a slick video touting the URL where students can check whether they've been admitted. (Last year's video documented a massive project that involved 30 sacks of charcoal plus several hundred pounds of — no, that would be telling...)

But in 2018 Dean of Admissions Stu Schmill appeared in a Star Wars-themed video titled "The Last Dean." (The 2017 video had also paid homage to another Disney franchise...) So for 2020, MIT's video returned again to their version of Star Wars universe.

Congratulations to the class of 2024! Even America's National Security Agency got into the Pi Day fun this year, daring readers on Twitter to try to crack the code hidden in this sentence:

"Now, I make a tasty delicious or hidden treat and share messages decrypted through numbering..."

"Well, those crazy chemistry cats have done it," writes Science Alert: Nearly 200 years after the molecule was discovered by Michael Faraday, researchers have finally revealed the complex electronic structure of benzene. This not only settles a debate that has been raging since the 1930s, this step has important implications for the future development of opto-electronic materials, many of which are built on benzenes.

The atomic structure of benzene is pretty well understood. It's a ring consisting of six carbon atoms, and six hydrogen atoms, one attached to each of the carbon atoms. Where it gets extremely tricky is when we consider the molecule's 42 electrons. "The mathematical function that describes benzene's electrons is 126-dimensional," chemist Timothy Schmidt of the ARC Centre of Excellence in Exciton Science and UNSW Sydney in Australia told ScienceAlert. "That means it is a function of 126 coordinates, three for each of the 42 electrons. The electrons are not independent, so we cannot break this down into 42 independent three-dimensional functions.The answer computed by a machine is not easy to interpret by a human, and we had to invent a way to get at the answer...."

"The electrons with what's known as up-spin double-bonded, where those with down-spin single-bonded, and vice versa," Schmidt said in statement. "That isn't how chemists think about benzene." The effect of this is that the electrons avoid each other when it is advantageous to do so, reducing the energy of the molecule, and making it more stable.

"Mats Järlström's emotions were clearly visible Friday morning. After years of arguing red light traffic cameras are flawed, the official Journal of the Institute of Transportation Engineers said he was right," reports a local news station in Portland, Oregon: The ITE sets traffic policy recommendations for the United States — and they said cities should be using his formula. "It is a big deal," Järlström told KOIN 6 News. "It's the top."

Six years ago he tried to tell the Beaverton City Council there's a problem with its red light cameras. Then there was the State of Oregon, which fined him for practicing engineering without a license. He had to file a federal lawsuit to continue his research to prove drivers making turns at intersections often get caught in a dilemma when they're slowing down to make a turn and the yellow light isn't long enough.

Järlström said he used 8th-grade math skills to prove drivers have been getting tickets they can't avoid.
"It didn't take an engineering license to realize that the formula for traffic light timing was flawed," Järlström says on the Institute for Justice site. "I'm just glad that the ITE and the professional engineering community were willing to listen to an outsider, consider my work, and finally update their formula."

"The First Amendment protects Americans' right to speak regardless of whether they are right or wrong," said the Institute for Justice attorney who represented Järlström. "But in Mats's case, the ITE committee's decision suggests that he not only has a right to speak, but also, that he was right all along." The ITE's vote updates a 55-year-old equation, the site reports.

Järlström added, "We will never know how many Americans have received red light tickets for making perfectly safe right-hand turns."

darenw shares a report: Freeman J. Dyson, a mathematical prodigy who left his mark on subatomic physics before turning to messier subjects like Earth's environmental future and the morality of war, died on Friday at a hospital near Princeton, N.J. He was 96. His daughter Mia Dyson confirmed the death. As a young graduate student at Cornell in 1949, Dr. Dyson wrote a landmark paper -- worthy, some colleagues thought, of a Nobel Prize -- that deepened the understanding of how light interacts with matter to produce the palpable world. The theory the paper advanced, called quantum electrodynamics, or QED, ranks among the great achievements of modern science. But it was as a writer and technological visionary that he gained public renown.

He imagined exploring the solar system with spaceships propelled by nuclear explosions and establishing distant colonies nourished by genetically engineered plants. "Life begins at 55, the age at which I published my first book," he wrote in "From Eros to Gaia," one of the collections of his writings that appeared while he was a professor of physics at the Institute for Advanced Study in Princeton -- an august position for someone who finished school without a Ph.D. The lack of a doctorate was a badge of honor, he said. With his slew of honorary degrees and a fellowship in the Royal Society, people called him Dr. Dyson anyway. Further reading: Slashdot's interview with Freeman Dyson (2013).

The New York Times: They asked Katherine Johnson for the moon, and she gave it to them. Wielding little more than a pencil, a slide rule and one of the finest mathematical minds in the country, Mrs. Johnson, whose death at 101 was announced on Monday by NASA, calculated the precise trajectories that would let Apollo 11 land on the moon in 1969 and, after Neil Armstrong's history-making moonwalk, let it return to Earth. A single error, she well knew, could have dire consequences for craft and crew. Her impeccable calculations had already helped plot the successful flight of Alan B. Shepard Jr., who became the first American in space when his Mercury spacecraft went aloft in 1961. The next year, she likewise helped make it possible for John Glenn, in the Mercury vessel Friendship 7, to become the first American to orbit the Earth. Yet throughout Mrs. Johnson's 33 years in NASA's Flight Research Division -- the office from which the American space program sprang -- and for decades afterward, almost no one knew her name.

Mrs. Johnson was one of several hundred rigorously educated, supremely capable yet largely unheralded women who, well before the modern feminist movement, worked as NASA mathematicians. But it was not only her sex that kept her long marginalized and long unsung: Katherine Coleman Goble Johnson, a West Virginia native who began her scientific career in the age of Jim Crow, was also African-American. In old age, Mrs. Johnson became the most celebrated of the small cadre of black women -- perhaps three dozen -- who at midcentury served as mathematicians for the space agency and its predecessor, the National Advisory Committee for Aeronautics. Their story was told in the 2016 Hollywood film "Hidden Figures," based on Margot Lee Shetterly's nonfiction book of the same title, published that year. The movie starred Taraji P. Henson as Mrs. Johnson, the film's central figure. It also starred Octavia Spencer and Janelle Monae as her real-life colleagues Dorothy Vaughan and Mary Jackson.

Long-time Slashdot reader sandbagger shared this report from the Hugo award-winning science fiction fanzine File 770: North Bellmore, New York fan Elyse Rosenstein, 69, died suddenly on February 20th. She had been undergoing rehabilitation after suffering a broken leg. At the time of her death, she was a retired secondary school science teacher. With Joyce Yasner, Joan Winston, Linda Deneroff and Devra Langsam, she organized the very first Star Trek convention, held in New York City in 1972. The convention was not only the very first media convention, it was also the biggest science fiction convention to date by a considerable margin...

At the time, Star Trek fans were often looked down on by many science fiction fans, who were more into books and magazines than TV shows. The pair hoped that a convention specifically geared towards Star Trek would do a lot to bring fans together. The rest, as they say, is fan history....

Elyse Rosenstein had a BS in physics and math, and an MS in physics, and taught science for more than two decades. She was a member of the New York Academy of Sciences and the Long Island Physics Teachers Association...

She was nicknamed "The Screaming Yellow Zonker" by Isaac Asimov.

An anonymous reader quotes a report from Observer: If you like to cook but not to shop or plan your own meals, and if you weren't too hungry, and if you didn't like cooking for too many friends, then Blue Apron -- the startup delivering precisely measured, prepackaged amounts of just enough salmon, green beans, butter and lemon for one meal, no leftovers -- was for you. Exactly who it was that was both upwardly mobile to pay for this service while also having a barren kitchen, nobody really knew -- but by the divine math of Silicon Valley gamblers, your existence made this an idea worth several billion dollars and potent enough to "disrupt" the grocery business. People actually believed this. Or they did until Jeff Bezos and Amazon went shopping and bought out Whole Foods. Or until HelloFresh launched. Or until Blue Apron spent millions on packaging and shipping, as well as marketing, literally gifting away boxes of neatly assorted ingredients to millennials who never ordered another box. All this conspired to, one-by-one, wreck Blue Apron's IPO, crater stock prices to all-time list lows, kick founders out of company leadership and now, at last, the seemingly undeniable, ultimate doom of the company.

After losing another $23.7 million in the last three months of 2019, Blue Apron is laying off 240 workers and shutting down the shop at its Arlington, Texas warehouse location. Blue Apron will keep, for now, its California and New York assembly-and-distribution shops, while leaders ponder peddling what's left at a paltry $50 million price tag. Meanwhile, customers continue to desert Blue Apron, down to 351,000 in the last quarter of 2019, from 557,000 the year before. Selling off Blue Apron that low would mean a loss in the neighborhood of $143 million for Blue Apron's capital investors, including Fidelity and Goldman Sachs. That hurts, but as usual, retail investors took the worst hit. Stock-market playing rubes, who bought in when Blue Apron went public at $11 a share, have lost more than 80% on their investment -- and that represents a recovery. Shares were trading for $3.60 at the close on Wednesday, up from 2018 when Blue Apron was worth less than a dollar. There's no other analysis than this: Blue Apron was one of the biggest-ever Silicon Valley catastrophes, a mix of hubris, unrealistic expectations, a misunderstanding of how people exist in the world -- and, Amazon.

An anonymous reader shares a problem that Amazon asks in its interviews: A cable of 80 meters is hanging from the top of two poles that are both 50 meters off the ground. What is the distance between the two poles (to one decimal point) if the center cable is (a) 20 meters off the ground and (b) 10 meters off the ground?

Andrew Yang, tech entrepreneur and founder of Venture for America, will end his campaign for president after a disappointing showing in the New Hampshire primary. The Washington Post reports: "I am a numbers guy," Yang said in an interview before addressing supporters at Manchester's Puritan Backroom. "In most of these [upcoming] states, I'm not going to be at a threshold where I get delegates, which makes sticking around not necessarily helpful or productive in terms of furthering the goals of this campaign. If I become persuaded that there's a particular candidate that gives us a superior chance of beating Donald Trump, and I think it's important to make that opinion known, then I would consider it for sure," Yang said. He also said he would be open to becoming another candidate's running mate or joining a presidential Cabinet.

In his stump speech, Yang warned of the societal and economic changes automation would continue to bring to the United States. He proposed countering it by implementing universal basic income in the form of a $1,000-a-month "Freedom Dividend" for U.S. citizens. His sometimes bleak message on the campaign trail was contrasted with his upbeat, irreverent style of campaigning: Yang once crowd-surfed at a candidate forum and sometimes challenged other celebrities to pickup basketball games. He half-danced onto just about every stage to the '90s Mark Morrison R&B hit "Return of the Mack" and spawned a loyal following of supporters who dubbed themselves the "Yang Gang." They often showed up at his events wearing trademark "math" hats, a nod both to his self-described emphasis on facts and research and to the geek culture that surrounded his candidacy. "This is the nerdiest campaign in history," Yang told The Washington Post last year. Yang was also the first presidential candidate to use campaign funds for a pilot program meant to resemble his universal basic income proposal. "He told CNN on Monday that the concept of a freedom dividend was 'not going anywhere,' and emphasized on Tuesday that he had forced a new idea into Democratic politics," reports The Washington Post. "He made that point with math."

"Now, 66 percent of Democrats support a universal basic income," Yang said. "It's got 72 percent of young people, aged 18 to 34."

By exploiting randomness, three mathematicians have proved an elegant law that underlies the chaotic motion of turbulent systems. From a report: Picture a calm river. Now picture a torrent of white water. What is the difference between the two? To mathematicians and physicists it's this: The smooth river flows in one direction, while the torrent flows in many different directions at once. Physical systems with this kind of haphazard motion are called turbulent. The fact that their motion unfolds in so many different ways at once makes them difficult to study mathematically. Generations of mathematicians will likely come and go before researchers are able to describe a roaring river in exact mathematical statements. But a new proof finds that while certain turbulent systems appear unruly, they actually conform to a simple universal law. The work is one of the most rigorous descriptions of turbulence ever to emerge from mathematics. And it arises from a novel set of methods that are themselves changing how researchers study this heretofore untamable phenomenon.

"It may well be the most promising approach to turbulence," said Vladimir Sverak, a mathematician at the University of Minnesota and an expert in the study of turbulence. The new work provides a way of describing patterns in moving liquids. These patterns are evident in the rapid temperature variations between nearby points in the ocean and the frenetic, stylized way that white and black paint mix together. In 1959, an Australian mathematician named George Batchelor predicted that these patterns follow an exact, regimented order. The new proof validates the truth of "Batchelor's law," as the prediction came to be known. "We see Batchelor's law all over the place," said Jacob Bedrossian, a mathematician at the University of Maryland, College Park and co-author of the proof with Alex Blumenthal and Samuel Punshon-Smith. "By proving this law, we get a better understanding of just how universal it is."

An anonymous reader quotes a report from Ars Technica: The Trump administration has for several years been working to weaken federal vehicle fuel-efficiency standards. To justify these changes, regulatory agencies argued that more stringent standards would both cost consumers more and reduce road safety. A draft version of the new final rule, however, seems to directly contradict those lines of reasoning. The draft of the Safer Affordable Fuel-Efficient (SAFE) Vehicles rule has not been released publicly, but Sen. Thomas Carper (D-Del.) has seen it. In a letter (PDF) to the White House, Carper says not only is the rule "replete with numerous questionable legal, procedural, and technical assertions," as well as "apparent typographical and other errors," but it also completely fails to provide the safety or economic benefits initially claimed.

"Remarkably, the costs of the Trump administration's draft final rule exceed its benefits to Americans" relative to the current standards. The senator writes: "While the draft final rule finds that the per vehicle purchase price would be reduced relative to the Obama rules by $977 (EPA greenhouse gas standards)/$1,083 (DOT's fuel economy standards), the draft final rule also projects that the increased gasoline consumers would have to use to operate the less fuel-efficient vehicles would ad $1,461 (EPA greenhouse gas standards)/$1,423 (DOT fuel economy standards) to these costs. Adding hundreds of dollars to the cost of each vehicle would seem to be the opposite of the more "affordable" vehicles the SAFE rule promised." Further, Carper notes, the estimate of lives potentially saved over a nearly 50-year time period by upgrading to new cars does not take into account the lives potentially lost to illness and disease attributable to increased pollution from less efficient cars. And of course, Carper notes, lower fuel-economy standards that result in consumers buying and using more gas, means burning more fossil fuels at a time when we should be doing the opposite. "My office's review of the draft final rule indicates that it utterly fails to provide any demonstrable safety, environmental, or economic benefit to consumers or the country," Carper concludes. "It should be abandoned. At a minimum, I seek your commitment that you will not allow the finalization of this extreme and unlawful environmental rollback in any form that even remotely resembles" the current draft.

Slashdot reader JoshuaZ writes:
In a major breakthrough in quantum computing it was shown that MIP* equals RE. MIP* is the set of problems that can be efficiently demonstrated to a classical computer interacting with multiple quantum computers with any amount of shared entanglement between the quantum computers. RE is the set of problems which are recursive; this is essentially all problems which can be computed.

This result comes through years of deep development of understanding interactive protocols, where one entity, a verifier, has much less computing power than another set of entities, provers, who wish to convince the verifier of the truth of a claim. In 1990, a major result was that a classical computer with a polynomial amount of time could be convince of any claim in PSPACE by interacting with an arbitrarily powerful classical computer. Here PSPACE is the set of problems solvable by a classical computer with a polynomial amount of space. Subsequent results showed that if one allowed a verifier able to interact with multiple provers, the verifier could be convinced of a solution of any problem in NEXPTIME, a class conjectured to be much larger than PSPACE. For a while, it was believed that in the quantum case, the set of problems might actually be smaller, since multiple quantum computers might be able to use their shared entangled qubits to "cheat" the verifier. However, this has turned out not just to not be the case, but the exact opposite: MIP* is not only large, it is about as large as a computable class can naturally be.

This result while a very big deal from a theoretical standpoint is unlikely to have any immediate applications since it supposes quantum computers with arbitrarily large amounts of computational power and infinite amounts of entanglement.

The paper in question is a 165 tour de force which includes incidentally showing that the The Connes embedding conjecture, a 50 year old major conjecture from the theory of operator algebras, is false.

The university underemployed more than 1,000 students -- primarily undergraduates in computer science and engineering -- in order to avoid paying union benefits, UAW Local 2865 says. From a report: The University of California at Berkeley owes student workers $5 million in back pay, a third-party arbitrator ruled on Monday, teaching assistants at the university say. More than 1,000 students -- primarily undergraduates in Berkeley's electrical engineering and computer science department -- are eligible for compensation, the United Auto Workers (UAW) Local 2865, which represents 19,000 student workers in the University of California system, told Motherboard. In some cases, individual students will receive around $7,500 per term, the union says. "This victory means that the university cannot get away with a transparent erosion of labor rights guaranteed under our contract," Nathan Kenshur, head steward of UAW Local 2865 and a third-year undergraduate math major at Berkeley, told Motherboard.

Thanks to their union contract, students working 10 hours a week or more at Berkeley are entitled to a full waiver of their in-state tuition fees, $150 in campus fees each semester, and childcare benefits. (Graduate students also receive free healthcare.) But in recent years, Berkeley has avoided paying for these benefits, according to UAW Local 2865. Instead, the university has hired hundreds of students as teaching assistants with appointments of less than 10 hours a week. On Monday, an arbitrator agreed upon by the UAW and the university ruled that Berkeley had intentionally avoided paying its student employees' benefits by hiring part-time workers. It ordered the university to pay the full tuition amount for students who worked these appointments between fall 2017 and today, a press release from the union says.

According to physicist Jason Steffen, letting slower passengers board airplanes first actually results in a more efficient process and less time before takeoff. An anonymous reader shares a report from Ars Technica: Back in 2011, Jason Steffen, now a physicist at the University of Nevada, Las Vegas, became intrigued by the problem and applied the same optimization routine used to solve the famous traveling salesman problem to airline boarding strategies. Steffen fully expected that boarding from the back to the front would be the most efficient strategy and was surprised when his results showed that strategy was actually the least efficient. The most efficient, aka the "Steffen method," has the passengers board in a series of waves. "Adjacent passengers in line will be seated two rows apart from each other," Steffen wrote at The Conversation in 2014. "The first wave of passengers would be, in order, 30A, 28A, 26A, 24A, and so on, starting from the back."

Field tests bore out the results, showing that Steffen's method was almost twice as fast as boarding back-to-front or rotating blocks of rows and 20-30 percent faster than random boarding. The key is parallelism, according to Steffen: the ideal scenario is having more than one person sitting down at the same time. "The more parallel you can make the boarding process, the faster it will go," he told Ars. "It's not about structuring things as much as it is about finding the best way to facilitate multiple people sitting down at the same time." Steffen used a standard agent-based model using particles to represent individual agents. This latest study takes a different approach, modeling the boarding process using Lorentzian geometry -- the mathematical foundation of Einstein's general theory of relativity. Co-author Sveinung Erland of Western Norway University and colleagues from Latvia and Israel exploited the well-known connection between microscopic dynamics of interacting particles and macroscopic properties and applied it to the boarding process. In this case, the microscopic interacting particles are the passengers waiting in line to board, and the macroscopic property is how long it takes all the passengers to settle into their assigned seats. The paper has been published in the journal Physical Review E.

Sabine Hossenfelder, research fellow at the Frankfurt Institute for Advanced Studies, writes: What we have here in the foundation of physics is a plain failure of the scientific method. All these wrong predictions should have taught physicists that just because they can write down equations for something does not mean this math is a scientifically promising hypothesis. String theory, supersymmetry, multiverses. There's math for it, alright. Pretty math, even. But that doesn't mean this math describes reality. Physicists need new methods. Better methods. Methods that are appropriate to the present century. And please spare me the complaints that I supposedly do not have anything better to suggest, because that is a false accusation. I have said many times that looking at the history of physics teaches us that resolving inconsistencies has been a reliable path to breakthroughs, so that's what we should focus on. I may be on the wrong track with this, of course.

Why don't physicists have a hard look at their history and learn from their failure? Because the existing scientific system does not encourage learning. Physicists today can happily make career by writing papers about things no one has ever observed, and never will observe. This continues to go on because there is nothing and no one that can stop it. You may want to put this down as a minor worry because -- $40 billion dollar collider aside -- who really cares about the foundations of physics? Maybe all these string theorists have been wasting tax-money for decades, alright, but in the large scheme of things it's not all that much money. I grant you that much. Theorists are not expensive. But even if you don't care what's up with strings and multiverses, you should worry about what is happening here. The foundations of physics are the canary in the coal mine. It's an old discipline and the first to run into this problem. But the same problem will sooner or later surface in other disciplines if experiments become increasingly expensive and recruit large fractions of the scientific community. Indeed, we see this beginning to happen in medicine and in ecology, too.

An anonymous reader quotes Ars Technica: The next big thing in 3D printing just might be so-called "4D materials" which employ the same manufacturing techniques, but are designed to deform over time in response to changes in the environment, like humidity and temperature. They're also sometimes known as active origami or shape-morphing systems. MIT scientists successfully created flat structures that can transform into much more complicated structures than had previously been achieved, including a human face. They published their results last fall in the Proceedings of the National Academy of Sciences...

MIT mechanical engineer Wim van Rees, a co-author of the PNAS paper, devised a theoretical method to turn a thin flat sheet into more complex shapes, like spheres, domes, or a human face. "My goal was to start with a complex 3-D shape that we want to achieve, like a human face, and then ask, 'How do we program a material so it gets there?'" he said. "That's a problem of inverse design..." van Rees and his colleagues decided to use a mesh-like lattice structure instead of the continuous sheet modeled in the initial simulations. They made the lattice out of a rubbery material that expands when the temperature increases. The gaps in the lattice make it easier for the material to adapt to especially large changes in its surface area. The MIT team used an image of [19th century mathematician Carl Friedrich] Gauss to create a virtual map of how much the flat surface would have to bend to reconfigure into a face. Then they devised an algorithm to translate that into the right pattern of ribs in the lattice.

They designed the ribs to grow at different rates across the mesh sheet, each one able to bend sufficiently to take on the shape of a nose or an eye socket. The printed lattice was cured in a hot oven, and then cooled to room temperature in a saltwater bath.

And voila! It morphed into a human face.
"The team also made a lattice containing conductive liquid metal that transformed into an active antenna, with a resonance frequency that changes as it deforms."