Latest news with #Fermilab
Chicago Tribune
3 days ago
- Science
- Chicago Tribune
John Peoples, Fermilab director at time of top quark discovery, dies
Physicist John Peoples Jr. was the third-ever director of Fermi National Accelerator Laboratory near Batavia, and in his 10 years in charge oversaw efforts to boost the power of the Tevatron, a circular particle accelerator that in 1995 contributed to the discovery of the top quark, the largest of all observed elementary particles. Scientists who study the building blocks of matter had widely believed since 1977 that the top quark existed, as it was the last undiscovered quark, or elementary particle, predicted by current scientific theory. The discovery, considered to be one of the most significant discoveries in science, advanced scientists' understanding of the fundamentals of the universe. 'He was so committed to the lab and he was able to master so many details related to the lab that if you just brought your A game, you were already in trouble,' said Joel Butler, former chair of Fermilab's department of physics and fields. 'But he managed to inspire us all — he was so good at things himself that he inspired us to achieve more than we thought we possibly could. He was an exemplar.' Peoples, 92, died of natural causes June 25 at the Oaks of Bartlett retirement community in Bartlett, said his son-in-law, Craig Duplack. Born in New York City, Peoples grew up in Staten Island and received a bachelor's degree in 1955 from Carnegie Institute of Technology, then a doctorate in physics in 1966 from Columbia University. He taught physics at Columbia and at Cornell University before joining Fermilab in 1971, four years after it opened. He was made head of the lab's research division in 1975. Peoples became a project manager in 1981 for the lab's Tevatron collider, a 4-mile ring on the lab site where collisions of particles occurred until it was shut down in 2011. After a brief detour in 1987 to work on a collider at the Lawrence Berkeley Laboratory in California, Peoples returned to Fermilab in 1988 as deputy director. He was promoted the following year to replace the Nobel Prize-winning Leon Lederman as Fermilab's director. 'He was an extremely hard worker,' said retired Fermilab Chief Operating Officer Bruce Chrisman. 'He was dedicated to the science, and he visited every experiment at midnight — because that's when students were running the thing, and he would show up in control rooms for the various experiments just to talk to them and see how things were going from their perspective.' Peoples lobbied federal legislators in the 1990s to retain funding as Fermilab physicists worked to try to discover the top quark and solve other essential puzzles about the universe. Peoples secured $217 million in funding in 1992 for a new main injector, or an oval-shaped ring, that allowed scientists to stage about five times more collisions each year, thus keeping the U.S. internationally competitive in the field of high-energy physics. Peoples oversaw the shutdown of the scuttled next-generation particle accelerator project known as the Superconducting Super Collider, or SSC, in Texas that was canceled by lawmakers in 1993 because of rising costs. 'When he became director, the decision to place the SSC in Texas had been made, and the lab was in a state of demoralization that we had been bypassed despite the fact that we had the capability to (host) the SSC, so John had to develop a plan,' Butler said. 'He positioned us for both alternatives — he positioned us successfully for what would happen if the SSC ran into trouble, which it did, but he also had a plan to keep us prosperous and contributing to the forefront of science for at least the decade that it took to build the SSC.' 'He tried to respect the fact that the people at the SSC — many of whom were looking for jobs — they were good people. They were not the problem why the SSC failed,' Butler said. In 1994, Fermilab researchers tentatively announced that they had found evidence of the long-sought top quark, although a second team working independently said more work was needed. 'We've been improving the collider and the detectors at the lab to the point where they are much more powerful now than ever anticipated when they were built,' Peoples told the Tribune in 1994. 'We're continuing to upgrade them, and we're arriving at a place where investigations can go forward that will assure this lab's future into the next century.' The following year, both teams of physicists formally confirmed that they had isolated the top quark. 'We're ecstatic about this,' Peoples told the Tribune in 1995. 'It's been a goal of this lab for a long time.' Peoples subsequently oversaw efforts to learn whether a common but elusive particle called a neutrino has any mass. He also led efforts to expand the laboratory into experimental astrophysics and modernize Fermilab's computing infrastructure to enable it to handle the demands of high-energy physics data. As an advocate for scientific research, Peoples reasoned that seemingly arcane discoveries can unexpectedly yield astonishing and wide-range applications and results. 'The things that we do, even when they become extraordinarily practical, we have no idea that they will,' he told the Tribune's Ted Gregory in 1998. In 1999, Peoples stepped down as Fermilab's director to return to research. He remained closely involved at Fermilab, and he also oversaw the Sloan Digital Sky Survey in New Mexico, which is a wide-ranging astronomical survey, from 1998 until 2003. After that, Peoples oversaw the Dark Energy Survey, another astronomical survey, for a time. Peoples retired from Fermilab in 2005, but remained director of the Dark Energy Survey until 2010. In 2010, Peoples was awarded the Robert R. Wilson Prize for Achievement in the Physics of Particle Accelerators — named for Fermilab's first director — from the American Physical Society. Peoples' wife of 62 years, Brooke, died in 2017. A daughter, Vanessa, died in 2023, and another daughter, Jennet, died several decades earlier. There were no other immediate survivors. There were no services.
Indian Express
6 days ago
- Science
- Indian Express
Matter's elusive dark twin: Most expensive substance in the universe
In 1930, theoretical physicist Paul Dirac was trying to reconcile quantum mechanics with Einstein's theory of relativity when his equations hinted at something strange: the existence of a 'mirror' particle identical to the electron, but with opposite charge. Its implications made him uneasy — that every particle has an antiparticle, and that perhaps the whole of nature is constructed in this way. Dirac's calculation wasn't to be a mere mathematical quirk. Two years later, American particle physicist Carl Anderson found the positron, the electron's antimatter twin, in cosmic ray experiments. It was a moment of rare scientific poetry: a particle predicted by pure mathematics, then seen in nature. Antimatter sounds like something from science fiction. And indeed, it has captured the imagination of writers from Star Trek (where it powers warp drives) to Angels and Demons (where it threatens to obliterate Vatican City). But antimatter is very real, though vanishingly rare in our universe. Whenever a particle meets its antiparticle, they annihilate in a flash of energy — converting all their mass, as per Einstein's , into pure light. That property makes antimatter the most energy-dense substance imaginable. A single gram could, in theory, produce as much energy as a nuclear bomb. But if it's so powerful, why don't we use it? And why don't we see it everywhere? Here lies one of the deepest mysteries in cosmology. The Big Bang, as we understand it, should have created equal amounts of matter and antimatter. But for reasons not yet fully known, the early universe tipped the scales ever so slightly toward matter — by just one part in a billion. That tiny excess is what makes up everything we see: stars, galaxies, people, planets. The rest annihilated with its antimatter counterpart in the early universe. Physicists are still trying to understand why the universe has this imbalance. One possibility is that antimatter behaves slightly differently than matter — a tiny asymmetry in how particles decay, known as CP violation. Experiments at CERN and Fermilab are probing these effects, but so far, no definitive explanation has emerged. The reality of antimatter: not just theory Despite its elusiveness, antimatter isn't merely theoretical. We make it — routinely. In fact, hospitals around the world use positrons (antimatter electrons) every day in PET scans. The 'P' in PET stands for 'positron,' and the scan works by injecting a radioactive tracer that emits positrons. When these encounter electrons in the body, they annihilate and emit gamma rays, which are detected to create precise images of tissues. Physicists at CERN's Antimatter Factory even trap anti-hydrogen atoms, composed of an antiproton and a positron, in magnetic fields for a few milliseconds at a time, to study their properties. The dream is to answer a simple but profound question: does antimatter fall down like regular matter, or does it somehow respond differently to gravity? Early experiments suggest it falls the same way, but the precision isn't yet conclusive. Energy source or weapon? Harnessing antimatter sounds like a sci-fi superpower, and indeed, the energy from matter-antimatter annihilation could, in theory, power spacecraft far more efficiently than any rocket we've built. But there's a catch: antimatter is mind-bogglingly expensive. Producing a single gram would cost about $60 trillion using today's particle accelerators. Worse, storing it safely is a nightmare. Let it touch anything, and boom, it annihilates. That hasn't stopped the speculation. NASA has funded studies on antimatter propulsion, suggesting it could one day shorten interstellar travel. But for now, it remains out of reach, a gleaming prize at the edge of possibility. Antimatter in space Cosmic rays from deep space occasionally strike Earth's upper atmosphere, producing short-lived showers of antimatter particles. The International Space Station even carries an instrument called the Alpha Magnetic Spectrometer, scanning for signs of antimatter nuclei that could hint at entire regions of the universe made of antimatter — a speculative idea, but one not yet ruled out. Neutron stars and black hole jets may also generate antimatter in tiny amounts, adding to the cosmic fireworks. But overall, the universe appears matter-dominated. Why nature chose this option, why there's something instead of nothing, remains among the deepest riddles in physics. Final Reflections In Star Trek, antimatter is a tame servant of human ambition. In reality, it's a fleeting, elusive shadow of the particles we know. Dirac's equations suggested a universe with perfect symmetry, but nature, like a mischievous artist, left a flaw in the mirror. The story of antimatter reminds us that physics isn't just about numbers or formulas. It's about imagination, daring, and a relentless curiosity about the hidden sides of reality. Somewhere in the collision of matter and anti-matter lies a spark — of annihilation, yes, but also of wonder. Shravan Hanasoge is an astrophysicist at the Tata Institute of Fundamental Research.
Gizmodo
09-07-2025
- Science
- Gizmodo
Record-Setting Qubit Performance Marks Important Step Toward Practical Quantum Computing
The promise of so-called 'quantum advantage' is simple. By harnessing the counterintuitive rules of quantum mechanics, quantum computers should be able to—in theory—surpass the computational potential of any classical supercomputer. But before quantum advantage drastically changes information technology as we know it, researchers have yet to address the many hurdles that are preventing quantum computers from entering into the mainstream. That said, quantum computing as a field has evolved dramatically over the last few years, and physicists are increasingly getting better at dealing with the extreme quirkiness of these potentially revolutionary systems. One such breakthrough concerns qubits—the smallest unit of information for quantum computers, much like a classical bit (0 or 1) on an ordinary computer. In a paper published Tuesday in Nature Communications, researchers announced a major milestone in improving the quality of qubits: a record-breaking coherence time for transmon qubits, a type of superconducting qubit. Their record—a maximum duration of 1 millisecond—far surpasses the previous time of 0.6 milliseconds, set by Fermilab last year. Scientists are interested in coherence time for a variety of reasons. Unlike classical binary bits, qubits can exist in superpositions of multiple states, much like different points on a sphere. This particularity of qubits allows quantum bits to carry and process an exponentially larger load of data on a scale that far outperforms any conventional supercomputer. Ironically, it's this exact quality that also makes qubits extremely sensitive to background noise, meaning they 'kind of pick up everything you also don't want,' explained Mikko Möttönen, the paper's senior author, during a video call with Gizmodo. When this happens, the qubits lose the valuable information they contain in a process called qubit decoherence. To accommodate for this data loss, scientists commonly apply a procedure called quantum error correction, in which they place single, physical qubits (like a transmon chip) into an intricate circuit collectively referred to as a 'logical qubit,' said Ioan Pop, a physicist at the Karlsruhe Institute of Technology in Germany, during a video call with Gizmodo. Although not involved in the study, Pop—a collaborator of Möttönen on a separate project—noted that such arrangements help quantum computers 'fight decoherence more effectively.' But quantum error correction can't completely recover the information lost from decoherence, prompting Möttönen and his team to investigate alternative approaches for fabricating the physical qubits themselves. The steps they took ranged from testing multiple wiring arrangements to simply making sure they had clean interfaces for the circuits. After multiple attempts, they stumbled upon a revision that resulted in a record-breaking coherence time of 1 millisecond. This might seem like an insignificantly small amount of time, but it's long enough for quantum computers to perform a tremendous number of complex operations, Möttönen explained (generally, qubits operate on a time of nanoseconds; one millisecond is equivalent to one thousand nanoseconds). Longer coherence time should reduce the amount of time and energy that goes into quantum error correction, Möttönen, a physicist at Aalto University in Finland, added. While there's no known way to completely eliminate qubit decoherence—a highly unlikely possibility—longer coherence times mean less frequent errors, especially when qubit numbers are scaled up, as is often the case with many existing quantum computers. For example, Google's Sycamore processor, which the company claimed had achieved quantum advantage in 2019, featured 53 qubits, whereas Quantinuum's processor, which supposedly outperformed Google's results, had 56 (to be clear, neither result, while impressive, actually achieved quantum advantage). 'I think the paper shows how much you can gain from being very careful with the fabrication,' said Pop. 'Am I surprised that clearing interfaces gives better qubits? I would say I'm not surprised. Am I impressed that they managed to do it? Yes—because it's not easy to control; it's basically like cooking, and it's very difficult to keep all parameters under control.' Having said that, the new result is more akin to one of 'probably a hundred or thousand more of these steps' to get to where we ultimately want quantum computers to go in terms of functionality, Pop added. 'I think what's super exciting is now that these quantum computers are already so accurate that you can do reasonable circuits,' Möttönen said. 'I think we just need them to be a little bit better [functionally], not just one random result but something more concrete. It will take a few years but not so long. It seems to be quite close.'
Yahoo
18-06-2025
- Science
- Yahoo
Physicists Found a New Clue That Could Reveal the Fifth Force
Here's what you'll learn when you read this story: The Standard Model of Particle Physics accounts for four fundamental forces—strong, weak, electromagnetism, and gravity—but for decades, scientists have wondered if an elusive fifth force might be at work. A new study analyzing the atomic transition of five calcium isotopes constrains the mass of a particle that would carry such a force from somewhere around 10 to 10 million electronvolts. It's still possible that these anomalies could be explainable via the standard model. The Standard Model of Particle Physics is a scientific masterpiece, but even so, it remains unfinished. For example, we still don't know why there is matter at all (a.k.a. matter-antimatter asymmetry), and then there's the whole dark matter and dark energy thing. Another source of some scientific quandary is whether there might be a fifth fundamental force. You might be familiar with the standard four—the strong force, the weak force, gravity, and electromagnetism—but some physicists wonder if a fifth force that couples together neutrons and electrons could also be at work throughout our universe. Now, an international collaboration of scientists from Germany, Switzerland, and Australia have discerned the upper limit of a particle that could carry such a force by looking at transition frequencies of five calcium isotopes. Those masses were penciled out to around 10 to 10 million electronvolts (yes, electron volts are sometimes used as mass measurements—thanks E=mc2). The results of the study were published in the journal Physical Review Letters. To arrive at this number, the researchers observed the atomic transitions of calcium-40, calcium-42, calcium-44, calcium-46, and calcium-48. An atomic transition occurs when an electron—attracted to the positively charged particles in a nucleus—briefly jumps to a higher energy level. These atomic transitions can vary based on the isotope and are influenced by the number of neutrons present in an atom. Once the observations were complete, the authors mapped the variations they recorded on what's called a King plot. According to the Standard Model, this should produce a linear plot. However, that is not what the study found. Due to the high sensitivity of the experiment, the plot ended up being nonlinear, suggesting that the deviations detected by the team could be evidence of a fifth force. That said, as the authors also note, it could also be attributable to something that is explainable within the Standard Model. However, whatever was causing these deviations, it didn't detract from the scientists' ability to set the upper limit of what the mass of the fifth-force boson might be. The search for this fifth force is a long one, and it's a scientific endeavor that's cast quite a wide net. For a while in the 1980s, scientists at MIT thought antigravity could be a fifth force, and another idea known as 'quintessence' gained popularity at the turn of the century. Recently, Fermilab in Chicago thought that they might be closing in on a fifth force, though their final results of the 'muon g-2' experiment largely confirmed the standard model. Other efforts have looked at much larger bodies than just atoms for evidence of the fifth force. Los Alamos National Laboratory published a study last year suggesting that by closely analyzing the orbits of asteroids and sussing out any deviations of those orbit, we could learn something about particle forces we don't understand. That team's ultimate aim, much like that of the team behind this new paper, was to understand the constraints on where this fifth force might reside. For now, the search continues, but scientists are taking more and more steps toward a physics-altering answer. You Might Also Like The Do's and Don'ts of Using Painter's Tape The Best Portable BBQ Grills for Cooking Anywhere Can a Smart Watch Prolong Your Life?
Yahoo
10-06-2025
- Science
- Yahoo
A Blockbuster ‘Muon Anomaly' May Have Just Disappeared
The Standard Model of particle physics—the best, most thoroughly vetted description of reality scientists have ever devised—appears to have fended off yet another threat to its reign. At least, that's one interpretation of a long-awaited experimental result announced on June 3 by physicists at the Fermi National Accelerator Laboratory, or Fermilab, in Batavia, Ill. An alternative take would be that the result—the most precise measurement ever made of the magnetic wobble of a strange subatomic particle called the muon—still remains the most significant challenge to the Standard Model's supremacy. The results have been posted on the preprint server and submitted to the journal Physical Review Letters. The muon is the electron's less stable, 200-times-heavier cousin. And like the electron and all other charged particles, it possesses an internal magnetism. When the muon's inherent magnetism clashes with an external magnetic field, the particle precesses, torquing to and fro like a wobbling, spinning top. Physicists describe the speed of this precession using a number, g, which almost a century ago was theoretically calculated to be exactly 2. Reality, however, prefers a slightly different value, arising from the wobbling muon being jostled by a surrounding sea of 'virtual' particles flitting in and out existence in the quantum vacuum. The Standard Model can be used to calculate the size of this deviation, known as g−2, by accounting for all the influences of the various known particles. But because g−2 should be sensitive to undiscovered particles and forces as well, a mismatch between a calculated deviation and an actual measurement could be a sign of new physics beyond the vaunted Standard Model's limits. [Sign up for Today in Science, a free daily newsletter] That's the hope, anyway. The trouble is that physicists have found two different ways to calculate g−2, and one of those methods, per a separate preprint paper released on May 27, now gives an answer that closely matches the measurement of the muon anomalous magnetic moment, the final result from the Muon g−2 Experiment hosted at Fermilab. So a cloud of uncertainty still hangs overhead: Has the most significant experimental deviation in particle physics been killed off by theoretical tweaks just when its best-yet measurement has arrived, or is the muon g−2 anomaly still alive and well? Vexingly, the case can't yet be conclusively closed. The Muon g−2 Collaboration announced the results on Tuesday in a packed auditorium at Fermilab, offering the audience (which included more than 1,000 people watching via livestream) a brief history of the project and an overview of its final outcome. The heart of the experiment is a giant 50-foot-diameter magnet, which acts as a racetrack for wobbling muons. In 2001, while operating at Brookhaven National Laboratory on Long Island, this ring revealed the initial sign of a tantalizing deviation. In 2013 physicists painstakingly moved the ring by truck and barge from Brookhaven to Fermilab, where it could take advantage of a more powerful muon source. The Muon g−2 Collaboration began in 2017. And in 2021 it released the first result that strengthened earlier hints of an apparent anomaly, which was bolstered further by additional results announced in 2023. This latest result is a capstone to those earlier measurements: the collaboration's final measurement gives a value of 0.001165920705 for g−2, consistent with previous results but with a remarkable precision of 127 parts per billion. That's roughly equivalent, it was noted during the June 3 announcement, to measuring the weight of a bison to the precision of a single sunflower seed. Despite that impressive feat of measurement, interpretation of this result remains an entirely different matter. The task of calculating Standard Model predictions for g−2 is so gargantuan that it brought together more than 100 theorists for a supplemental project called the Muon g−2 Theory Initiative. 'It is a community effort with the task to come up with a consensus value based on the entire available information at the time,' says Hartmut Wittig, a professor at the University of Mainz in Germany and a member of the theory initiative's steering committee. 'The answer to whether there is new physics may depend on which theory prediction you compare against. The consensus value should put an end to this ambiguity.' In 2020 the group published a theoretical calculation of g−2 that appeared to confirm the discrepancy with the measurements. The May preprint, however, brought significant change. The difference between theory and experiment is now less than one part per billion, a number both minuscule and much smaller than the accompanying uncertainties, which has led to the collaboration's consensus declaration that there is 'no tension' between the Standard Model's predictions and the measured result. To understand what brought this shift in the predictions, one has to look at one category of the virtual particles that cross the muons' path. '[Excepting gravity] three out of the four known fundamental forces contribute to g−2: electromagnetism, the weak interaction and the strong interaction,' Wittig explains. The influence of virtual photons (particles of light that are also carriers of the electromagnetic force) on muons is relatively straightforward (albeit still laborious) to calculate, for instance. In contrast, precisely determining the effects of the strong force (which usually holds the nuclei of atoms together) is much harder and is the least theoretically constrained among all g−2 calculations. Instead of dealing with virtual photons, those calculations grapple with virtual hadrons, which are clumps of fundamental particles called quarks glued together by other particles called (you might have guessed) gluons. Hadrons can interact with themselves to create tangled, precision-scuttling messes that physicists refer to as 'hadronic blobs,' enormously complicating calculations of their contributions to the wobbling of muons. Up to the 2020 result, researchers indirectly estimated this so-called hadronic vacuum polarization (HVP) contribution to the muon g−2 anomaly by experimentally measuring it for electrons. One year later, though, a new way of calculating HVP was introduced based on lattice quantum chromodynamics (lattice QCD), a computationally intensive methodology, and quickly caught on. Gilberto Colangelo, a professor at the University of Bern in Switzerland and a member of the theory initiative's steering committee, points out that, currently, 'on the lattice QCD side, there is a coherent picture emerging from different approaches. The fact that they agree on the result is a very good indication that they are doing the right thing.' While the multiple flavors of lattice QCD computations improved and their results converged, though, the experimental electron-based measurements of HVP went the opposite way. Among seven experiments seeking to constrain HVP and tighten predictive precision, only one agreed with the lattice QCD results, while there was also deviation among their own measurements. 'This is a puzzling situation for everyone,' Colangelo notes. 'People have made checks against each other. The [experiments] have been scrutinized in detail; we had sessions which lasted five hours.... Nothing wrong was found.' Eventually, the theory initiative decided to use only the lattice QCD results for the HVP factor in this year's white paper, while work on understanding the experimental results is going on. The choice moved the total predicted value for g−2 much closer to Fermilab's measurement. The Standard Model has seen all of its predictions experimentally tested to high precision, giving it the title of the most successful theory in history. Despite this, it is sometimes described as something unwanted or even failed because it does not address general open questions, such as the nature of dark matter hiding in galaxies. In the solid terms of experimental deviations from its predictions, this century has seen the rise and fall of many false alarms. If the muon g−2 anomaly goes away, however, it will also take down some associated contenders for new, paradigm-shifting physics; the absence of novel types of particles in the quantum vacuum will put strong constraints on 'beyond the Standard Model' theories. This is particularly true for the theory of supersymmetry, a favorite among theorists, some of whom have tailored a plethora of predictions explaining away the muon g−2 anomaly as a product of as-yet-unseen supersymmetric particles. Kim Siang Khaw, an associate professor at Shanghai Jiao Tong University in China and a member of Fermilab's Muon g−2, offers a perspective on what will follow. 'The theory initiative is still a work in progress,' he says. 'They may have to wait several more years to finalize. [But] every physics study is a work in progress.' Khaw also mentions that currently Fermilab is looking into repurposing the muon 'storage ring' and magnet used in the experiment, exploring more ideas that can be studied with it. Finally, on the theory front, he muses: 'I think the beauty of [the g−2 measurement] and the comparison with the theoretical calculation is that no matter if there is an anomaly or no anomaly, we learn something new about nature. Of course, the best scenario would be that we have an anomaly, and then we know where to look for this new physics. [But] if there is nothing here, then we can look somewhere else for a higher chance of discovering new physics.'
