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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

#201

Post by Isinlor »

rthomas6 wrote: post #104
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…

I wonder if some rich people could start a form of charity where they just pay a few incredibly brilliant people a good salary to go do whatever research they want for the rest of their lives. Sort of like patronage. Just bypass the whole grant funding cycle and work on whatever you want, because you're a genius and want to study things other people don't like or understand.

Something like OpenAI?

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

#202

Post by EForEndeavour »

pdonis wrote: post #182
EForEndeavour wrote: post #159

Earlier quoted context omitted.

The same way we distinguish the shadows cast in Plato's cave from the objects occluding the light. The more situations in which a theory or model makes accurate predictions, the more correct it is. Epicycles are much, much more wrong than mathematically perfect elliptical orbits.

> Epicycles are much, much more wrong than mathematically perfect elliptical orbits. Not if you define "wrong" as "inaccurate predictions". You can approximate ellipses with circles and epicycles to any desired degree of accuracy by putting in more epicycles. So you can match the predictions of ellipses to any desired accuracy with epicycles. Also, as I noted, the actual orbits of the planets are not perfect ellipses…

You're being intentionally obtuse. "Just add more epicycles!" isn't building a better model (for a sensible definition of "better"). It's just overfitting. You are the reason why regularization exists. https://en.wikipedia.org/wiki/Regularization_(mathematics)

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

#203

Post by awwx »

cli wrote: post #141

I suppose this is as an appropriate time as any to ask for advice: I am a multimillionaire from inheritance, and am about to complete my masters in physics. I wish to work on long term theoretical physics problems that do not seem to be possible under the current publish-or-perish academic system. The plan was to complete a PhD, then leave academia, but lately I have been having severe doubts about continuing onto a…

I suggest asking Dr. Hossenfelder directly.

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

#204

Post by ZenPsycho »

Koshkin wrote: post #198
ZenPsycho wrote: post #169

Earlier quoted context omitted.

Right, so what was ground breaking about General Relativity, is that it challenged the newtonian axioms (assumptions) that there's a single universal clock, and that all objects within the universe are effectively rigid and exist in something resembling euclidian geometric space, and all move forward through time at the same speed. Newtonian physics explains many things very well, but couldn't explain other phenomeno…

> Quantum physics, can also predict everything in general relativity Unfortunately, the two theories, while both being extremely successful and accurate in their predictions, are incompatible with one another. Quantum Field Theory has successfully combined Quantum Mechanics with Special Relativity, but that is all.

thanks for letting me know- I’m not a physicist so I knew I was probably putting my foot in my mouth somewhere.

maybe some day we’ll find the grand unifying theory of the universe.

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

#205

Post by XorNot »

Koshkin wrote: post #198
ZenPsycho wrote: post #169

Earlier quoted context omitted.

Right, so what was ground breaking about General Relativity, is that it challenged the newtonian axioms (assumptions) that there's a single universal clock, and that all objects within the universe are effectively rigid and exist in something resembling euclidian geometric space, and all move forward through time at the same speed. Newtonian physics explains many things very well, but couldn't explain other phenomeno…

> Quantum physics, can also predict everything in general relativity Unfortunately, the two theories, while both being extremely successful and accurate in their predictions, are incompatible with one another. Quantum Field Theory has successfully combined Quantum Mechanics with Special Relativity, but that is all.

We need to to be specific here though: they are compatible at low energies. They only become incompatible at very high energy states like those shortly after the big bang, and those we can't produce easily in particle accelerators.

Which is to say: they break under conditions very unlike the every-day universe, which is important but also indicative that they are not that broken.

The incompatibility is important though, because if there's any more card tricks we can do with physics so we can do interesting things, somewhere in that bit of incompatibility is where we must find it.

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

#206

Post by ymolodtsov »

trainingaccount wrote: post #75
andrepd wrote: post #69

Earlier quoted context omitted.

>Can you tell me how to calculate whether a system of particles will cause another system of particles to collapse or not? You appear to be somewhat mistaken. Copenhagen interpretation does not postulate any specific explanation or mechanism for wave-function collapse, merely that "upon measurement, the wave-function collapses into an eigenstate of the observable being measured". This, of course, is a physically veri…

You really want to look into the delayed choice eraser... it's mind blowing.

And it is still explained by the Copenhagen interpretation and there’s no problems with it. It’s like all those SR paradoxes that sound interesting but don’t disprove the theory — just the fact you don’t fully understand it.

The major interpretations of QM are all similar in the fact that they are not testable and don’t really affect the resulta. It’s metaphysics.

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

#207

Post by ymolodtsov »

perl4ever wrote: post #187
sanxiyn wrote: post #161

Earlier quoted context omitted.

I should correct an important misconception. Epicycles do not produce correct predictions. Epicycles can produce correct point location of planets, but do not produce correct phase. Galileo observed heliocentrism-compatible phase of Venus with his telescope. That was the crucial experiment, not the simplicity.

I don't think it's important to my point. The point remains that multiple theories can be equivalent in some restricted sense, yet the more aesthetic one might have greater potential.

But it matters. All the major interpretations give you the same results (otherwise we’d just test it and rule out the wrong ones).

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

#208

Post by ymolodtsov »

tbabb wrote: post #33
empath75 wrote: post #26

Earlier quoted context omitted.

> suppressed "unconventional" interpretations of quantum mechanics (like the many worlds interpretation) in favor of the obviously-wrong Copenhagen interpretation. They’re just interpretations and they all work equally well and produce the same predictions. It makes no sense to call any of them obviously wrong. It’s personal preference.

Copenhagen is wrong to the degree that any theory can be called wrong. It posits specific physical events (collapse) which are not only unsupported by evidence, and not only contradicted by evidence (delayed choice quantum eraser experiments), and not only logically self contradictory (when it is not too vague to make concrete statements about the phenomena it is explaining, it is circular-- our theory of electrons c…

MW might be simpler in the way it arises but while it produces the same results it doesn’t really matter. And it definitely has enough supporters to ruin the “stubborn physicists” hypothesis.

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

#209

Post by ymolodtsov »

amai wrote: post #140

Maybe physics is suffering from the https://en.m.wikipedia.org/wiki/Streetlight_effect . Colliders used to produce helpful results for fundamental physics, but maybe it is time to look somewhere else.

Colliders are certainly not the only thing scientists use.

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

#210

Post by ncmncm »

CydeWeys wrote: post #144
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

This isn't true though. They said the same thing over a century ago, yet if you took those people and plopped them into the present they'd be unable to explain such an important everyday technology as GPS, because it requires an understanding of general relativity to work. We don't know what we don't know. It's very likely that more discoveries will result in obvious changes that are visible in everyday life, like GP…

> "they'd be unable to explain ... GPS, because it requires an understanding of general relativity to work.

It requires GR to make it work, but not GR to understand how it works. I.e., GPS would work fine -- in fact, be easier -- in a world without GR. The clocks on board the satellites depend on QM, but the idea of an accurate clock is easy. Same with orbits -- staged rockets came late, but orbital mechanics goes back a long way. Transistors are new, but amplification is old.

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