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A deepening crisis forces physicists to rethink the structure of nature’s laws
- ohiovr 5y agoThey should have known how wrong they were when they saw the motion of galaxies right then and there.
- KolenCh 5y agoSummary: # Background material - Fundamental (particle) Physics has no progress since the 1970s. - discovery of Higgs is confirmation of old Physics. - other predicted fundamental particles has never been discovered. - Fine tuning problems - smallness of Higgs mass - smallness of the cosmological constants - reductionism as Kenneth Wilson's concept of effective field theory (EFT) - separation of scales—UV (small scales) can be treated as a cut off of IR (large scales). # Main message The 2 fine tuning problems above are examples that are UV-sensitive, unlike other usual examples in EFT. This is hint of physics that mixes UV and IR scale: example of black hole—higher energy -> larger event horizon. > "Gravity is anti-reductionist" Then it went on to cites these papers pointing to relevant research about this idea: * [\[0801.2562\] Naturally Speaking: The Naturalness Criterion and Physics at the LHC](https://arxiv.org/abs/0801.2562 https://arxiv.org/abs/0801.2562) * [Phys. Rev. Lett. 82, 4971 (1999) - Effective Field Theory, Black Holes, and the Cosmological Constant](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.82.4971 https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.82...) * [\[2107.03530\] Densities of States and the CKN Bound](https://arxiv.org/abs/2107.03530 https://arxiv.org/abs/2107.03530) * [\[2106.04622\] Calculating the Higgs Mass in String Theory](https://arxiv.org/abs/2106.04622 https://arxiv.org/abs/2106.04622) * [\[hep-th/9912072\] Noncommutative Perturbative Dynamics](https://arxiv.org/abs/hep-th/9912072 https://arxiv.org/abs/hep-th/9912072) * [\[1909.01365\] IR Dynamics from UV Divergences: UV/IR Mixing, NCFT, and the Hierarchy Problem](https://arxiv.org/abs/1909.01365 https://arxiv.org/abs/1909.01365) * [\[1904.08426\] The Weak Scale from Weak Gravity](https://arxiv.org/abs/1904.08426 https://arxiv.org/abs/1904.08426) * [\[1305.6939\] Natural Tuning: Towards A Proof of Concept](https://arxiv.org/abs/1305.6939 https://arxiv.org/abs/1305.6939) * [Phys. Rev. Lett. 127, 101101 (2021) - Hidden Symmetry of Vanishing Love Numbers](https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.127.101101 https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.12...)
- peter303 5y agoThe muon was the first WhatTheF particle discovered from cosmic rays. It and its associated quarks and leptons do not appear to participate in any physics necessary for the observable universe functioning. And the muon vexes us again with an observed g2 moment the differs from its theoretical value greater than measurement error. This again suggests there is more unknown physics out there.
- lumost 5y agoI strongly suspect that new high energy physics advances will come from investigating astronomically generated phenomenon. - Gravitational Waves for probing extremely large and small objects - Cosmic Rays for probing high energy particles. - Solar probes to detect particles made from stellar phenomena
- leashless 5y agoI think these datasets also point the way to some new physics. https://slate.com/technology/2021/07/shane-harris-interview-uap-ufo-report.html https://slate.com/technology/2021/07/shane-harris-interview-...
- leashless 5y agoAlthough to get anything useful out of them would require the radar data, not just the optical data. Much more certain positioning than optical cameras on fast moving platforms.
- tsimionescu 5y agoOh yes, definitely new physics will come out of studying grainy footage of unidentified objects that are most likely drones or birds and well known optical phenomena that "military experts" can't seem to grasp (parallax).
- bigbillheck 5y agoDepends on what you mean by 'observable'. Proton mass (for example) depends in part on all 3 generations of quarks.
- oraphalous 5y agoI wish they didn't use the term "crisis" for this. It's nothing like the problems other disciplines are having with respect to replication failure - where maybe the term is appropriate. Physics can still explain / predict a shit-load of phenomena. It's not a crisis - just more work to do.
- brummm 5y agoI mean, replication failures are a result of bad science, bad analysis and a poor understanding of statistics in many cases. It's not so much a crisis in the state of human knowledge but the state of the education of the scientists in those other disciplines.
- naasking 5y agoIt's a crisis because it's so widespread and the denial that it's a problem is strong.
- pasadenasunset 5y agoThe phenomena are related, though. One could argue that the social sciences, with greater latitude in definitions of measurement and thresholds for statistical significance, had been building sand castles for decades. Eventually, the entire rotten edifice will collapse. In contrast, the greater restrictions of theory and measurement in physical science didn’t easily allow researchers to do pointless hand-waving that looked good. In some sense, the “crisis” in physics is less embarassing, as it is simply theorists bumping into limits enforced by reality. They didn’t make it up as they went along. I’m also doubtful the lauded “open science” movement will accomplish anything besides the mass transfer of intellectual property to centralized data platforms, to be mined by replication specialists. I’m biased, admittedly, after watching an APA zoom conference on the advantages and wonders of open science, and why researchers should join in. The lead presenter’s #1 reason to join open science was “that I didn’t lose my data anymore, it was all nicely and neatly centralized on the OSF server.” Speechless.
- robwwilliams 5y agoIn biology, neuroscience, and psychology replication failure is often the result of an impedance mismatch between reductive models and real systems complexity. This is an acute problem in animal research where 90% of work gets away with using a single genotype in a single environment. And then the “wise” old heads at NIH wonder that there is a replication bias? Really?
- brummm 5y agoThere is a slight mistake in the article. The standard model does not describe the neutrinos. In the standard model neutrinos are massless particles, but in reality they are not.
- KolenCh 5y agoI understand your point, but depending on who you ask, the (massive) neutrinos are well described in the Standard Model framework, just we we don't know exactly what that term looks like. So depending on who you ask, they may not regard (massive) neutrinos as "beyond standard model".
- pdonis 5y ago> The standard model does not describe the neutrinos. In the standard model neutrinos are massless particles, but in reality they are not. That's a bit strong. The SM still makes good predictions for many processes involving neutrinos. We just know, since the discovery of neutrino masses, that the SM, or at least the original version of it (there are proposed mechanisms that can handle neutrino masses without modifying anything else in the SM, although they still have some issues), can only be an approximation regarding neutrinos. But the SM is pretty much considered an approximation (or, as it is usually termed, an effective field theory) anyway.
- deleted 5y ago[deleted]
- ncmncm 5y agoI have been as derisive as anybody about string theory's entire lack of experimentally realizable predictions. But some things give me pause. The first is its interpretation of black holes as existing entirely at the event horizon surface, with no actual space-time inside; and the black hole entropy exactly matching the set of states of strings living in the 2D horizon layer. Eliminating that singularity is a big delivery. This seems like another case where it can deliver something useful.
- KolenCh 5y agoI don't see your train of thought here, you first mention the lack of "experimentally realizable predictions", i.e. not falsifiable, and then gives one of the many examples that string theory solved without being able to experimentally verified. Why would that give you a pause? How this single example is different from all other "predictions" from string theory?
- akvadrako 5y agoHow does that depend on string theory? Also, what do you mean by "string theory"? Do you mean M-theory?
- ssivark 5y agoPer current understanding, “M-theory” is one of five consistent descriptions of string theory , all of which are supposed to be related by dualities i.e. each description makes certain aspects easily manifest, but they’re all equally “correct”.
- lazide 5y agoThe biggest problem with string theory near as I can tell is it doesn’t make any falsifiable predictions. So it’s basically junk.
- ssivark 5y agoEh, that's a highly uncharitable statement. Frameworks like "differential equations" or "group theory" or "quantum mechanics" also don't make falsifiable predictions (till you build a system-specific model which you can then compare against experiment) -- but that doesn't make them any less useful. String theory in this unusual place between a physics model and a mathematical framework (that's what makes it so "fundamental"), and we are still in the process of figuring out how to construct predictive physical models using this framework. But OTOH it's been enormously useful in helping us theoretically probe and understand structural properties of quantum field theories, the implications of special symmetries, the geometry of manifolds, etc.
- Jerry2 5y agoProf. Sabine Hossenfelder has a great article on the lack of progress in fundamentals of physics: "The present phase of stagnation in the foundations of physics is not normal " [1] Choice quotes: >We know this both because dark matter is merely a placeholder for something we don’t understand, and because the mathematical formulation of particle physics is incompatible with the math we use for gravity. Physicists knew about these two problems already in 1930s. And until the 1970s, they made great progress. But since then, theory development in the foundations of physics has stalled. If experiments find anything new now, that will be despite, not because of, some ten-thousands of wrong predictions. >Ten-thousands of wrong predictions sounds dramatic, but it’s actually an underestimate. I am merely summing up predictions that have been made for physics beyond the standard model which the Large Hadron Collider (LHC) was supposed to find: All the extra dimensions in their multiple shapes and configurations, all the pretty symmetry groups, all the new particles with the fancy names. You can estimate the total number of such predictions by counting the papers, or, alternatively, the people working in the fields and their average productivity. According to her, and many other physicists, there hasn't been any major progress in phenomenology since 1970s when Higgs boson was postulated. [1] https://backreaction.blogspot.com/2018/11/the-present-phase-of-stagnation-in.html https://backreaction.blogspot.com/2018/11/the-present-phase-...
- KolenCh 5y ago"The Trouble with Physics" by Lee Smolin also talk about this, and the general "group-think" situation of theoretical physics.
- ramraj07 5y agoYou don’t even need to be a physicist to see that they haven’t introduced anything new physics wise in the last 5 decades. Alcubierre drive maybe?
- whatshisface 5y agoOff the top of my head, they've made progress in quark-gluon plasma, discovering the AdS/CFT correspondence, and practical techniques for quantum computing. There's been enormous progress in computational methods, too. There's also been something very interesting going on with twistors. Oh, and 50 years ago quantum field theory was not on a formally sound footing, but now it is (not completely but it's closer). There's also a lot of progress in renormalization (RG group flow). Oh, and don't forget about fifty years of Moore's law. We have solid state to thank for that. I'm sure I could think of more if I gave it more time. The truth is that there have been no earthshattierng paradigm shifts in the last fifty years, but that's OK because they tend to happen once every couple centuries.
- anamax 5y agoWolfram might disagree about the "lack of progress" in the fundamentals of physics. It's said that every cosmologist who dies gets to add a "law of nature" consistent with known observations. I wonder what Conway added.
- antonvs 5y agoWhat progress would Wolfram point to? Please don't tell me the answer involves cellular automata. That's completely unsupported by any evidence.
- mrjangles 5y ago[flagged]
- nomel 5y ago> Experimentalists finally made a device that could image the atoms in the glass Is this x-ray crystallography?
- morei 5y agoNo, because glass isn't a crystal. This is part of why it was such a hard problem: Because the existing sub-molecule imaging techniques couldn't image it.
- analog31 5y ago>>>> Anyway, my point is, if someone claims to be a scientist who understands the structure of the entire universe and creation, but can't understand the structure of the windows in your house, they are probably full of shit. My advice to anybody who is troubled by the apparent certainty of science, is: Get to know some actual scientists. Disclosure: I'm an industrial physicist. The imaging technique might be cryo-TEM (cryogenic transmission electron microscopy), which is also how we get those spectacular pictures of the COVID virus.
- forum_ghost 5y ago[dead]
- jbay808 5y ago> if someone claims to be a scientist who understands the structure of the entire universe and creation, but can't understand the structure of the windows in your house, they are probably full of... Isn't that like saying that if you meet someone who claims to know all the rules of chess, but still can't find a way to checkmate Garry Kasparov, they are also full of it?
- x3n0ph3n3 5y ago
- stjohnswarts 5y agoI hate when people call it a “crisis” . Science has brought us amazing insights and capabilities. It's not in a crisis. They will simply have to shift gears and work on other projects if they have dug as far as they can for now with today's technology and mathematics. There is still plenty to spend human brain power on and physicists have plenty of new places to go to.
- KolenCh 5y agoWell, it is a crisis to people who bet their career in this field. These people are here to stay (in the field) and since there are no experimental progress that shed lights on fundamental physics, the effort of all these people are stuck in coming up with theories in existing paradigm that is still compatible with the increasingly more stringent limit from experimental physics. They didn't shift gears and work on other projects. The whole field bet in String Theory and are stuck. Like explained in the book "The Trouble with Physics", it is a career suicide for people not wanting to deal with String Theory and still be a theoretical physicists in high energy physics. One may say a similar crisis has happened by the end of 19-th century. All but a few peculiarity in Physics were explained by the then modern physics. Some thought theory of physics were almost "complete", and only later to find out a major paradigm shift (actually 2, quantum theory and relativity) completely changed the way we viewed physics, and now becomes our cornerstone to understand physics. AFAIK, physicists generally like this kind of crisis, some make a career chasing crisis, because this might be the hint of new physics and the next paradigm shift.
- joe__f 5y agoI absolutely agree with this. There's also a quote in the article from one of the scientists saying they don't like calling it a crisis
- KolenCh 5y agoYou're quoting > “Some people call it a crisis. That has a pessimistic vibe associated to it and I don’t feel that way about it,” said Garcia Garcia. “It’s a time where I feel like we are on to something profound.” They are using past experience of a crisis (say from late 19-century) to infer what comes next is a major paradigm shift. This might very well be true, but we didn't know that. We should be optimistic about our career and the future of physics, true. But we should not be in denial that this is a crisis. There's absolutely no information (but hints) we have right now that tells you a breakthrough is coming. The next paradigm shift may happen in arbitrary far future, or may not happened at all if it is out of the reach of humanity. Also, people don't call it crisis just because we hit a wall. But we're hitting a half century wall now (since 1970s.)
- rossjudson 5y agoFirst Europe is broken, then the global climate, and now physics. Reality has had a bad week.
- sans-serif 5y agoThose are all "crises" in different senses of the word.
- wiz21c 5y agobut none of them brings a happy face...
- krazii 5y agoWhy does nature have to be lawlike?
- silent_cal 5y agoIf it wasn't, we couldn't do any science.
- dboreham 5y agoOtherwise there's no spec for the sim developers to follow.
- tsimionescu 5y agoNature doesn't have to be anything. However, a universe that doesn't have any laws would be an amorphous mush. Forget about planets and stars, it could not even have atoms or molecules - you need an awful lot of stable structure (i.e. laws) to get something as complex as a water molecule out of random particle interactions.
- ciphol 5y agoOur investigations ever since the scientific revolution have progressively shown it to be more and more lawlike. It would be a bit of a surprise if this stopped being true.
- silent_cal 5y agoScience assumes that nature is lawlike. Otherwise it would be senseless to make predictions.
- ciphol 5y agoYes - I would add that a philosophically-knowledgeable scientist knows that nature does not HAVE to be lawlike. But like you say, the process of science is hypothesizing laws and checking to see if those laws make predictions. So far this process has been very successful.
- pc2g4d 5y agoI like that they draw the Higgs boson as a D20 :-D
- yalogin 5y agoDo we know what the pay discrepancy between physics research and computer science and finance jobs. I wonder if we are attracting the brightest minds in high paying jobs.
- Havoc 5y agoCrisis sounds so negative. Isn’t this desirable. Ie means there is more to be discovered . I would have thought people in the field would be stoked about the possibilities
- mrich 5y agoJust recently finished the Three Body trilogy and there are some interesting connections to the described dilemma in there (alien objects hindering scientific progress of mankind by messing with particle colliders, n dimensional space and weapons that destroy whole dimensionalities)