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The present phase of stagnation in the foundations of physics is not normal

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Re: The present phase of stagnation in the foundations of physics is not normal

#81

Post by kgwgk »

rossdavidh wrote: post #30
letitgo12345 wrote: post #12

Well considering that we know everything pretty much about most of everyday physics and new physics requires energies that are almost unreachable and billions of dollars in experimental investment and/or years and decades to collect sufficient data, it's not a surprise at all that foundations of physics progress has slowed. I don't think the physics community is to blame here. Just the nature of reality

I agree, although I think it could be argued that a logical outcome of this fact, is that most (although hopefully not all) of the physicists should go work on other things, like maybe the physics of planet formation, where we are getting new data all the time. Or maybe in areas outside of physics altogether, like the social sciences, where again we have orders of magnitude more data than we once did. If the low-hang…

Physicists: https://www.xkcd.com/793/

Re: The present phase of stagnation in the foundations of physics is not normal

#82

Post by walrus1066 »

jsweojtj wrote: post #50
walrus1066 wrote: post #27

I think this is excessively harsh. The only guarantees made about the LHC were, that it would prove or disprove the existence of the Higgs Boson. Believe me, experimental physicists are desperate to find the slightest deviation from the standard model. I spent 2 years on one such 'stab in the dark' rare decay analysis! The SM's predictions have been tested to a rigor unparalleled in history. It predicts stuff like ma…

It does not predict the fine structure constant, that is an input into the model.

Yes, you're right.

I was getting it jumbled up with the magnetic moment of the electron, which is predicted by the SM (well, the QED part anyway), to be slightly different to the 'classical' prediction.

Experiment measurement of this is accurate to one part per billion, and is consistent with the QED prediction.

The electroweak bits of the SM predict the W & Z bosons, along with their masses, which have also been measured, to around 1 part per 10,000, and match SM predictions.

EDIT: last but not least, the Higgs Boson was also predicted by SM, with a ballpark figure for it's mass, and other properties (how often it decays into photons, W bosons, quarks etc). So far all measurements of these properties are consistent with SM predictions.

Re: The present phase of stagnation in the foundations of physics is not normal

#83

Post by TangoTrotFox »

a_crc wrote: post #24
ackfoo wrote: post #5

We’re stuck in a paradigm that doesn’t result in any valid fundamental predictions. The idea that running the expanding universe backward makes everything denser and hotter in the past is just dumb. The universe is not like a loaf expanding from dense batter to fluffy bread. Instead, the chaotic vacuum produces, for want of a more accurate concept, particle-antiparticle pairs at random that exert a “pressure” seen as…

That's an interesting idea. Do you have any thoughts on the fact that the structure of the cosmic microwave background radiation is exactly what we would expect it to be if the universe had expanded from a tiny state to its current state? I'm unwilling to assume it "just randomly looks like that" given that a random distribution on a universal scale seems highly unlikely to show the large scale structures notable in…

I'm in no way endorsing this individual's proposal, but the argument you're using here is not as strong as you'd expect. A recurring trend in the past several decades has been that a contradiction in prediction is often simply massaged back into that prediction, at times quite arbitrarily. Then that previously contradictory observation can be used as 'evidence' for the newly retrofitted prediction. Of course that's at best circular logic and, at worst, something that can start sending us spiraling down the wrong path, faster than light.

So for instance the CMB did not support the big bang, it contradicted it. See: the horizon problem [1]. To reconcile this inflation theory was invented which arbitrarily suggests that the universe hit the accelerator hard, then slowed back down. There's no logic, mechanism, rationale or falsifiability. But it makes what we see fit what we predicted we'd see, so it's a pretty widely accepted part of modern physics. And this retrofitting now has a cascade affect that enables other theories to provide support for yet other theories -- such as what you're proposing here in that the CMB now 'supports' the big bang. It does so only if you add a very big asterisk there.

[1] - https://en.wikipedia.org/wiki/Horizon_problem

Re: The present phase of stagnation in the foundations of physics is not normal

#84

Post by syncsynchalt »

gbumakefan wrote: post #8
tylermw wrote: post #3

Love this comment left on the post by Peter Shor (of Shor's algorithm--the algorithm that kicked off the quantum computing frenzy). I assume it's him and not an imposter. "It's not just that scientists don't want to move their butts, although that's undoubtedly part of it. It's also that they can't. In today's university funding system, you need grants (well, maybe you don't truly need them once you have tenure, but…

Except you can’t just go hide in your attic. Everyone is more risk averse than ever as the cost of housing, healthcare, and education relentlessly increase faster than wages.

Human productivity is at its highest point in human history, so one can't help but wonder why we must all work harder than our ancestors to exist.

Re: The present phase of stagnation in the foundations of physics is not normal

#85

Post by kgwgk »

FakeComments wrote: post #67
andrepd wrote: post #53

Earlier quoted context omitted.

>Physics is notoriously bad at having curiosity about strange, unconventional, or truly novel ideas. Physics of today would be unrecognisable to a scientist at the start of the 20th century. Indeed the physics of 1935 would be unrecognisable to a scientist at the start of the 20th century. Our understanding progressed enormously AND it did so because people put forward radical theories in complete rupture with the es…

> There is nothing "obviously wrong" about the standard Copenhagen interpretation. Copenhagen interpretation showed up when they were faced with a choice between preserving locality or determinancy. They chose wrong — we know now QM is non-local, and that the underlying justification for the Copenhagen model is an extraneous philosophical proposition. But much like an extra dependency in a software project, no one wa…

> we know now QM is non-local, and that the underlying justification for the Copenhagen model is an extraneous philosophical proposition.

What underlying justification are you talking about and what do you understand by "the Copenhagen model" precisely? At least in the Einstein vs Bohr debates the one denying that QM could be a complete theory because of its non-locality was Einstein, I think.

Re: The present phase of stagnation in the foundations of physics is not normal

#86

Post by scythe »

tylermw wrote: post #3

Love this comment left on the post by Peter Shor (of Shor's algorithm--the algorithm that kicked off the quantum computing frenzy). I assume it's him and not an imposter. "It's not just that scientists don't want to move their butts, although that's undoubtedly part of it. It's also that they can't. In today's university funding system, you need grants (well, maybe you don't truly need them once you have tenure, but…

>And if you submit a proposal that says "I'm going to go off and work on this crazy idea, and maybe there's a one in a thousand chance that I'll discover some of the secrets of the universe, and a 99.9% chance that I'll come up with bubkes," you get turned down.

>But if a thousand really smart people did this, maybe we'd actually have a chance of making some progress.

The problem is, as I understand it: suppose some people locked themselves in their attic and worked on physics problems; how does society know that they're actually working on physics and not merely twiddling their thumbs?

The whole publication-review-credit-tenure-grant circuit was invented to address exactly that situation. In order to replace it, you need some other way of convincing the funding bodies that their money is actually paying for something.

Re: The present phase of stagnation in the foundations of physics is not normal

#87

Post by thicknavyrain »

danbruc wrote: post #63
letitgo12345 wrote: post #12

Well considering that we know everything pretty much about most of everyday physics and new physics requires energies that are almost unreachable and billions of dollars in experimental investment and/or years and decades to collect sufficient data, it's not a surprise at all that foundations of physics progress has slowed. I don't think the physics community is to blame here. Just the nature of reality

Well considering that we know everything pretty much about most of everyday physics [...] That's true and also not true. Yes, we have a working theory that explains essentially everything with unprecedented accuracy as long as you don't wander too far outside of everyday length and energy scales. But on the other hand we still do not really understand basic quantum mechanics almost a century after its discovery or at…

Sure, but there are some interesting and affordable tabletop experiments being done to probe certain features of QM (like Weak Measurement: https://www.hep.ucl.ac.uk/qupot/) and test fundamental assumptions. The work on that front is progressing, but when people think of "Laws of Nature" i.e. GR and the Standard Model, short of expensive facilities like new particle colliders or telescope arrays like LSST and Cosmological surveys, it's unlikely "new physics" is going to be jumping out of the woodwork any time soon.

Which is not to say people aren't trying. Conferences are held probing this exact question (e.g. can we come up with DM detectors that aren't just enormous tanks of cooled liquids?) and trying new strategies. It's not like the community isn't engaging in good faith with some of these proposals, it's also that we haven't had a new hint of where to look from a collider experiment since the discovery of the Higgs. Despite everyone's best efforts. Yes, we need some experimental ingenuity to push through this frontier, but I also agree with OP that Physics is just being very stubborn against yielding any further secrets at present.

Re: The present phase of stagnation in the foundations of physics is not normal

#88

Post by T-A »

cletus wrote: post #36

I'm no physicist but this leaves me scratching my head. You have some people saying the university funding system is to blame by not accepting crazy ideas but we have all sorts of ideas in physics like: - String theory. As best as I can tell the only reason string theory exists is because if dimensions=11 the equations for general relativity pop out. Importantly though string theory has made no testable predictions a…

Depending on how strict you are, you can trace string theory all the way back to the 1940s, or at the very least to the late 60s [1]. Supersymmetry is from the early 70s [2]. They are exactly the mainstream kind of thing which Hossenfelder is referring to when she writes about "physics beyond the standard model which the Large Hadron Collider (LHC) was supposed to find". For every lone wanderer exploring a long shot like octonion math, there are thousands writing yet another paper on some variation of the old theme.

[1] https://en.wikipedia.org/wiki/History_of_string_theory

[2] https://en.wikipedia.org/wiki/Supersymmetry#History

Re: The present phase of stagnation in the foundations of physics is not normal

#89

Post by blueprint »

tbabb wrote: post #60
andrepd wrote: post #53

Earlier quoted context omitted.

>Physics is notoriously bad at having curiosity about strange, unconventional, or truly novel ideas. Physics of today would be unrecognisable to a scientist at the start of the 20th century. Indeed the physics of 1935 would be unrecognisable to a scientist at the start of the 20th century. Our understanding progressed enormously AND it did so because people put forward radical theories in complete rupture with the es…

> There is nothing "obviously wrong" about the standard Copenhagen interpretation Can you tell me how to calculate whether a system of particles will cause another system of particles to collapse or not? Can you tell me under what circumstances a system of particles will evolve unitarily or not? Can you shade the region of the spacetime diagram of EPR where the wavefunction is collapsed? How about in a delayed choice…

As if it's known that meaning itself is not a physical quantity

Re: The present phase of stagnation in the foundations of physics is not normal

#90

Post by maxxxxx »

EGreg wrote: post #43
gbumakefan wrote: post #8

Earlier quoted context omitted.

Except you can’t just go hide in your attic. Everyone is more risk averse than ever as the cost of housing, healthcare, and education relentlessly increase faster than wages.

This is one of the best arguments for UBI. Imagine how much humanity would innovate in science, open source and other public gift economies if everyone didn’t have to worry how they will eat and pay rent next month.

How about reducing the generally accepted working hours to something like 24 hrs/week? 40 is pretty arbitrary so we could arbitrarily set a lower number. That would free up a lot of creativity.
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