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Fundamental physics is dying? [video]

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Re: Fundamental physics is dying? [video]

#181
post #165

Earlier quoted context omitted.

IANAP but it seems that fundamental physics suffers from a lack of monotonicity of knowledge. Although physics does its best to explain things, those explanations are more like guesses than known facts. A theoretical physicist can have their life's work undone simply because someone else comes up with a better guess, or experiment says no. You spend your life working on SUSY and then... nope. Even very established kn…

ELI5 what is the G2 situation?

g-2. g minus 2. g is the magnetic moment of an electron. It is expected to be very close to 2. g minus 2 is a value that can be measured, and that can be calculated, both very precisely.

If I understand the current situation, for electrons g-2 agrees between experiment and measurement to 10 digits. For muons, though, it doesn't. (Muons are harder to measure, because they decay. And they are somewhat less well understood theoretically, so there's room on both sides of that question.)

Re: Fundamental physics is dying? [video]

#182

I know that this will probably be down-voted to death but I don't like these hyperbolic takes. I know that Sabine did use this title for click-bate purposes that she is now mostly doing YouTube videos (she had horrible experience that unfortunately not rare in scientific community [1]). I understand that the field of particle physics which is the corner stone in fundamental physics is not showing the great advances t…

Seems like you are not downvoted on HN for rational argumentation. I still think sabine has a point. When we consider occam's razor string theory is absurd. Just because einstein used math to show our perception of the world is flawed, doesn't mean it is likely repeatable with an overly complicated mathematical model. Yet we live in a world, where highly decorated physicists spin a tale of consciousness beeing enable…

My point was that sabine is claiming that the field is dying (or in a crisis). You can argue against string theory and quantum gravity research as much as you want. But this will not warrant sabine's conclusions about particle physics and why we should invest in other areas instead. She is doing this for almost a decade now.

And I don't understand your point about statistical interpretation and how it is related to being a religion. Pick up any of the mainstream interpretation and start doing calculations of lets say ground state energy of H atom and you will get the same results.

All mainstream interpretations yields the same results if calculations are done "correctly". The shut up and calculate works pretty well across interpretation because of two things you have to consider

The first thing is that all interpretations rely on four things to be able to do the calculations. ( I simplified a little bit)

1- Hilbert spaces to represent quantum states

2- Operators for observables (like momentum and energy)

3- Unitary evolution of states through the Schrödinger equation

4- Born’s rule for calculating probabilities of measurement outcomes

Thus, the underlying equations are the same regardless of interpretation.

The second thing you have to understand the role of Interpretations. They aim to explain what the mathematical structure of QM means. They differ on issues like: collapse, Is it real (Copenhagen)? just an apparent phenomenon (Many-Worlds)? or governed by additional variables (Bohmian mechanics) or the question of Determinism. Is the universe fundamentally deterministic (Bohmian mechanics)? or indeterministic (Copenhagen)?

The last thing is a really philosophical question about what exists physically—wavefunctions, particles, or multiple worlds?

These philosophical questions don’t affect the numerical predictions of quantum theory and that's part of the reason you shouldn't learn physics from science communication books.

Re: Fundamental physics is dying? [video]

#183
post #30

Earlier quoted context omitted.

30 years ago I spoke to a fairly well known and regarded physicist who said something rather interesting along the same lines. Quoting as accurately as I can "physics looks sexy from the outside due to some celebrities but inside it's mostly worse than anyone wants to admit." . He also suggested I go and study mathematics instead because at least there will likely be some applications for it. I did and I am glad I di…

Sounds like this criticism would be valid for fundamental physics but there are many other physics fields with experimental results that become technology.

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Re: Fundamental physics is dying? [video]

#184

Earlier quoted context omitted.

Seems like you are not downvoted on HN for rational argumentation. I still think sabine has a point. When we consider occam's razor string theory is absurd. Just because einstein used math to show our perception of the world is flawed, doesn't mean it is likely repeatable with an overly complicated mathematical model. Yet we live in a world, where highly decorated physicists spin a tale of consciousness beeing enable…

My point was that sabine is claiming that the field is dying (or in a crisis). You can argue against string theory and quantum gravity research as much as you want. But this will not warrant sabine's conclusions about particle physics and why we should invest in other areas instead. She is doing this for almost a decade now. And I don't understand your point about statistical interpretation and how it is related to b…

Thank you for the reply. I absolutely agree, but it's not only science communication and journalists that try to see it in a philosophical way.

Roger Penrose for example (as far as i can tell a highly respected physicist) is arguing that the collapse of the wave function happens inside the brain and enables our consiciousness.

Who am I to criticise that? I think we should be open to anything in science. On the other hand when one tries to do philosophy, one should also understand the field. For an outsider it looks like people try to flatter themselves with their superior mathematical skills.

Re: Fundamental physics is dying? [video]

#185

Earlier quoted context omitted.

I don't like Sabine Hossenfelder's videos because they're too short. When I want to relax after work by playing a game while listening to someone drone on on youtube on a deep and esoteric subject, her videos end way too soon, and with an advertisement for her sponsor. I just want to hear some rambling boffin expound for an hour in the background on some matter that can't possibly raise more than a few hundred views.…

Sean Carroll is my go to guy for long form physics and philosophy discussions that have some depth but are still accessible. His October AMA on the Mindscape podcast is over 4 hours, but I haven't listened to it yet.

Thanks for the recommendation. I'll give it a go.

Re: Fundamental physics is dying? [video]

#186
post #146

Earlier quoted context omitted.

I don't like Sabine Hossenfelder's videos because they're too short. When I want to relax after work by playing a game while listening to someone drone on on youtube on a deep and esoteric subject, her videos end way too soon, and with an advertisement for her sponsor. I just want to hear some rambling boffin expound for an hour in the background on some matter that can't possibly raise more than a few hundred views.…

> When I want to relax after work by playing a game while listening to someone drone on on youtube on a deep and esoteric subject Angela Collier is the answer to your plea.

Thanks, I'll try here too.

Re: Fundamental physics is dying? [video]

#187

Earlier quoted context omitted.

I think this guy has hit the nail on the head: https://energywavetheory.com/subatomic-particles/ Take a look at how stupidly complex the standard model is compared to the other: https://energywavetheory.com/equations/theory-comparison/ Everything in the universe on that site is eloquently and simply explained, including gravity as a shading effect (think an eclipse/water waves acting on an obstacle: https://www.thest…

Anyone claiming that string theory is part of "the standard model", when proposing their alternative theory, is probably a crank. Anyone deriving "E=mc²", and claiming that as evidence of their theory, is almost certainly a crank.

Sometimes I am wondering what if there is theory which have been on right track but it's (false?) falsified and already forgotten. Sure theory could be incomplete or incorrect on some ways but would that right part be noticed? For example I think it's too easy to imagine world where relativity or quantum theory would be socially falsified and/or left without any attention.

Simple example experience I had when I was beginning of my physic studies (which I never finished) was when discussed with elder/smarter student about wheel friction. I was explaining that I had figured out that wheel spin actually matters when there is also side slip. [Total slip direction is dependent from spin speed.] But because he -knew- that wheel spin does not matter and he -knew- that he was better/smarter/etc. he was so focused to correct my mistake I was unable to convince him. How much this happens on higher stakes?

So if situation is that there has not been much progress for a long time I think it could be valuable also understand these failed theories and of course very importantly why they are falsified.

When I am working with hard problem I usually go this order:

1. Describe the problem.

2. Describe bunch of naive solutions.

3. Describe problems in those naive solutions.

4. "Describe problems in those problems": Why some of those problems do not hold water. Those can be workarounded, fixed or they actually are not really problem in this case or maybe some combination of naive solution properties gives working solution.

Re: Fundamental physics is dying? [video]

#188
post #60

Earlier quoted context omitted.

Yes, there's definitely some interesting fields that are making progress that are still in the purview of "physics". Materials science, or condensed matter physics, is doing a lot of fascinating work with quasiparticles: https://en.wikipedia.org/wiki/Quasiparticle There's a number of fields you could call "quantum engineering" where physics and engineering work together on the cutting edge. Some of the output of that…

> It's particle physics that seems to be stuck in a rut. You could look at the discovery of tetraquarks and pentaquarks, and high precision tests of the standard model though as a lot of progress. What it hasn't done though is create some sexy upending of our current models of physics, we keep asking questions and mostly the responses coming back are in line with theories that we knew 40 years ago. But that's still a…

There hasn't been a total lack of progress by any means.

Unfortunately, "confirming the standard model again in some new way", while good science, also does nothing to get particle physics out of its rut.

I originally wrote "useful" science when I first wrote that sentence, but... it's debatable how useful it is, actually. People have been taught that measuring the utility of science is heresy, but I find that insane. It is completely possible to have science that isn't that useful, even to other science, let alone to any other purpose. Confirming the standard model yet harder isn't really useful. Of course, you have to run the experiments to confirm the standard model, in the hopes that maybe it won't, I'm saying the result of confirming the standard model is of debatable utility.

Re: Fundamental physics is dying? [video]

#189
I'm not hot on what fundamental physics looks like now or in the future, but there's an attitude that Sabine promotes that I see echoed in a lot of comments here which feeds into problems with research.

I don't think the work put into studying fundamentals was "a waste of time" thus far. It's dangerous to label experiments and ideas that were acted on in good faith as the best options at the time but didn't yield positive results as missteps.

Scientists need to be allowed to do work like this without fear because to do so otherwise leads to perverse incentives and you end up with things like lots of studies that can't be reproduced because of p-hacking or worse.

Arguing bad faith after the fact is awfully hard without real evidence and if you're going to discount anyone with enthusiasm for their research proposal based on enthusiasm alone you're not going to be left with a healthy program. I don't blame anyone who supported things like supersymmetry as an example for something which hasn't panned out. we're still left with a major mystery and big questions and it says we need to rethink things in more difficult directions.

Re: Fundamental physics is dying? [video]

#190
post #187

Earlier quoted context omitted.

Anyone claiming that string theory is part of "the standard model", when proposing their alternative theory, is probably a crank. Anyone deriving "E=mc²", and claiming that as evidence of their theory, is almost certainly a crank.

Sometimes I am wondering what if there is theory which have been on right track but it's (false?) falsified and already forgotten. Sure theory could be incomplete or incorrect on some ways but would that right part be noticed? For example I think it's too easy to imagine world where relativity or quantum theory would be socially falsified and/or left without any attention. Simple example experience I had when I was b…

Did you run the experiment? I don't think wheel spin does matter when there's side slip. It matters when there would otherwise be static friction (e.g. if you're in a car with an ABS system), but I don't think it matters when it's just kinetic friction. (Of course, there are other kinds of friction, which might behave differently. I'm no friction expert. I imagine things get weird when water's involved, though.)
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