Physics

From Lee Billings at Scientific American: Whatever dark matter is, it is not accounted for in the Standard Model of particle physics, a thoroughly-tested “theory of almost everything” forged in the 1970s that explains all known particles and all known forces other than gravity. Find the identity of dark matter and you illuminate a new path forward to a deeper understanding of the universe—at least, that is what physicists hope … “The desire is for dark matter to not only exist but also to solve other outstanding problems of the Standard Model,” says Jesse Thaler, a physicist at Massachusetts Institute of Technology. “Not every new discovery can be a revelation like the Higgs, where afterward theories suddenly fit together much Read More ›

From Stuart Clark at New Scientist: Although the scope of our definition determines the complexity of the puzzle, physics should still supply the solution, says philosopher Tim Maudlin of New York University. Physics is about just two questions, he says: “what exists?” and “what does it do?”. “If you answer both of those questions, then I think you have answered the question ‘what is reality?’.” More. (paywall) Reality isn’t “made of” anything. What is the number 2 “made of”? What is the political idea of proportional representation “made of”? What is the Rubaiyat of Omar Khayyam “made of”? Almost certainly, they will get nowhere, but at least they will be able to reaffirm their basic vision of life. Not bad Read More ›

From physicist Sabine Hossenfelder at Aeon: Might nature’s bottomless pits actually be ultra-efficient quantum computers? That could explain why data never dies … Hawking’s discovery of black-hole evaporation has presented theoretical physicists with a huge conundrum: general relativity says that black holes must destroy information; quantum mechanics says it cannot happen because information must live on eternally. Both general relativity and quantum mechanics are extremely well-tested theories, and yet they refuse to combine. The clash reveals something much more fundamental than a seemingly exotic quirk about black holes: the information paradox makes it aptly clear that physicists still do not understand the fundamental laws of nature. But Gia Dvali, professor of physics at the Ludwig-Maximilians University of Munich, believes he’s Read More ›

From JStor Daily: As late as 1923, a British physicist despaired his coevals were still “ignorant of Einstein’s work and not very much interested in it.” British physicists Ebenezer Cunningham and Norman R. Campbell were at first quite lonely introducing Einstein to their countrymen and challenging the “ethereal” view. Campbell seems to have been the only anti-ether voice from 1905 to 1911.More. Of course, in its day, ether was a reasonable belief as—in its day—was the belief that Earth was the point of the universe down to which all things fell (geocentric system). As anthropologist J. G. Frazer put it The views of natural causation embraced by the savage magician no doubt appear to us manifestly false and absurd; yet Read More ›

From Mike Wall at Space.com: “For decades, we’ve known of four fundamental forces: gravitation, electromagnetism, and the strong and weak nuclear forces,” Feng added. “If confirmed by further experiments, this discovery of a possible fifth force would completely change our understanding of the universe, with consequences for the unification of forces and dark matter.” … … The Hungarians detected tantalizing evidence of a previously unknown particle just 30 times heavier than an electron — a result they published early this year. More. It would make a heck of a sci fi film See also: Dark matter skeptics wanted Follow UD News at Twitter!

Alongside the proton? From ScienceDaily: The deuteron — one of the simplest atomic nuclei, consisting of just one proton and one neutron — is considerably smaller than previously thought, say researchers who measured the proton and found a significantly smaller value than previous research did, using new experimental methods. … The new measurement of the deuteron’s size has now given rise to an analogous mystery. It is possible that this will lead to an adjustment of the Rydberg constant, a fundamental quantity in physics. Another possible explanation is that a physical force as yet unknown is at work. More. See also: What no new particles means for physics? Follow UD News at Twitter!

From Quanta: In the past two years, some theoretical physicists have started to devise totally new natural explanations for the Higgs mass that avoid the fatalism of anthropic reasoning and do not rely on new particles showing up at the LHC. Last week at CERN, while their experimental colleagues elsewhere in the building busily crunched data in search of such particles, theorists held a workshop to discuss nascent ideas such as the relaxion hypothesis — which supposes that the Higgs mass, rather than being shaped by symmetry, was sculpted dynamically by the birth of the cosmos — and possible ways to test these ideas. Nathaniel Craig of the University of California, Santa Barbara, who works on an idea called “neutral Read More ›

From Columbia mathematician Peter Woit at Nott Even Wrong: The Nightmare Scenario Now back from a short vacation, and there seems to have been a lot happening on the debate over fundamental physics front. From the experimentalists, news that the Standard Model continues to resist falsification: More. See also: Physics to crack wide open? Of course, in this post-modern world, there’s an alternative to admitting we are completely lost—make up the missing data. Follow UD News at Twitter!

From T’Mir Danger Julius at RealClearScience: But just because our classical electromagnetic theories are consistent with our observations, that does not imply that there are no magnetic monopoles. Rather, this just means that there are no magnetic monopoles anywhere that we have observed. Once we start to delve into the murky depths of theory, we begin to find some tempting arguments for their presence in the universe.More. It’s August. See also: Is fine-tuning a fallacy? Follow UD News at Twitter!

From John Timmer at Ars Technica: Toward the end of last year, the people behind the Large Hadron Collider announced that they might have found signs of a new particle. Their evidence came from an analysis of the first high-energy data obtained after the LHC’s two general-purpose detectors underwent an extensive upgrade. While the possible new particle didn’t produce a signal that reached statistical significance, it did show up in both detectors, raising the hope that the LHC was finally on to some new physics. This week, those hopes have officially been dashed. Physicists used a conference to release their analysis of the flood of data that came out of this year’s run. According to their data, the area of Read More ›

Dan Falk here: Last month, about 60 physicists, along with a handful of philosophers and researchers from other branches of science, gathered at the Perimeter Institute for Theoretical Physics in Waterloo, Canada, to debate this question at the Time in Cosmology conference. The conference was co-organized by the physicist Lee Smolin, an outspoken critic of the block-universe idea (among other topics). His position is spelled out for a lay audience in Time Reborn and in a more technical work, The Singular Universe and the Reality of Time, co-authored with the philosopher Roberto Mangabeira Unger, who was also a co-organizer of the conference. In the latter work, mirroring Elitzur’s sentiments about the future’s lack of concreteness, Smolin wrote: “The future is Read More ›

From Jacob Aron at New Scientist:One of the world’s leading dark matter detectors has wrapped up a nearly two-year-long search for the mysterious particles, without finding a single whiff. The results suggest that the days may be numbered for the dominant model of dark matter. More. But then, this is from new Scientist, our favourite coffee room wowza. See also: New Scientist astounds: Information is physical Follow UD News at Twitter!

From Richard Webb: Quantum physicists just can’t agree on how to handle the fundamental uncertainty that apparently underpins reality. We round up their best attempts so far … In 2011, 33 physicists and philosophers at a conference in Austria on “Quantum physics and the nature of reality” were asked to nominate their favourites, listed below. The percentages of the delegates backing the various options do not add up to 100 – in keeping with the spirit of quantum theory, the poll allowed multiple answers. Here’s an interesting, moderately sane one: The information interpretation – 8 votes, 24 per cent Information-theory interpretations stem from a growing realisation among physicists that the most basic currency of reality might be not stuff, but Read More ›

Not according to theoretical physicist Sabine Hossenfelder on the diphoton bump, at Forbes: Despite the fact that it would be the nightmare of most of my colleagues, I’m hoping the diphoton bump turns out to be nothing more than noise. … During my professional career, all I have seen is failure. A failure, that is, of particle physicists to uncover a more powerful mathematical framework that improves upon the theories we already have. Yes, failure is part of science – it’s frustrating, but not worrisome. What worries me much more is our failure to learn from those failures. Rather than trying something new, we’ve been trying the same thing over and over again, expecting different results. … If the bump Read More ›

From Adam Frank at NPR: To begin with, it’s important to understand how much cosmology and physics has gotten right. Our ability to map out the history of the universe back to a fraction of an instant after its inception is a triumph of the human intellect and imagination. And because that history could not be told without a detailed description of matter and forces at a fundamental level, it’s clear we’ve done something remarkable — and remarkably correct. It’s the next steps down into reality’s basement, however, where the trouble seems to begin. Some researchers now see popular ideas like string theory and the multiverse as highly suspect. These physicists feel our study of the cosmos has been taken Read More ›