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Why the foundations of physics have not progressed for 40 years

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Re: Why the foundations of physics have not progressed for 40 years

#211

Post by yunesj »

jjmorrison wrote: post #77
SiempreViernes wrote: post #71

Personally I find it amusing Hossenfelder is now invoking the need for learning philosophy of science, given how hostile she's been to it before. See for instance http://backreaction.blogspot.com/2016/08/the-unbearable-ligh... that begins with: "Philosophy isn’t useful for practicing physicists. On that, I am with Steven Weinberg and Lawrence Krauss who have expressed similar opinions." Though to be fair, she clarifi…

I thought the article was not great. But the fact that she's changed her mind on the topic makes me like her a lot more. How can we learn more if we don't change our mind?

> How can we learn more if we don't change our mind?

I think it's also possible to learn without having strongly held beliefs about the subject beforehand. This alternative reminds me of Descartes (don't assimilate knowledge until you are sure of it's veracity) and Bayes (keep track of degree of belief about traditionally non-probabilistic things). Maybe such an approach would help getting trapped in local optima. E.g., I'd imagine it would be hard to climb out of the theist energy well once your world view were based on it.

Re: Why the foundations of physics have not progressed for 40 years

#212

Post by Nition »

tartoran wrote: post #207
Nition wrote: post #204

Earlier quoted context omitted.

Google Translate on this fails almost completely but somehow turns it into a critique on the Internet Of Things: Thirty spokes, there is a hub. When it is free, it is used for cars. I think it is a device, when it is free, it is used for devices. Profit, useless.

I get something like this from google translate: Thirty spokes, a total of one hub, when it is not available, there is a car. I think that when there is no device, there is a use for it. The chisel owner thinks that when there is no room, there is room. Therefore, it is good to use it, but not to use it. "

Interesting that we get different results. Google's AI-based translation can get a little crazy sometimes[1] but I would have still expected everyone to get the same result for the same thing.

Proof of mine: https://i.imgur.com/hb428NI.png

[1] DECEARING EGG comes to mind. https://www.youtube.com/watch?v=3-rfBsWmo0M

Edit: As someone else has now mentioned, it's the difference between leaving the quotes(「 and 」) on the ends or not. So it is just the translate AI being weird as usual.

Re: Why the foundations of physics have not progressed for 40 years

#213

Post by shuspect »

shuspect wrote: post #191
gus_massa wrote: post #148

Earlier quoted context omitted.

These theories have a very precise mathematical formulation and very weird unintuitive consequences. If you try to teach them without math, you only keep the weird unintuitive part and it's more unintelligible. For quantum mechanics you have to know eigenvalues and eigenvectors. This is studies in the first years of the university in a technical career. I'm not sure if it can be teach much earlier. For Special Relati…

We can keep math, but switch to better theories, with plausible explanations. A kind of Pilot Wave can explain quantum weirdness to layman people with ease. We can ditch theory relativity and calculate speeds relatively to CMB, which is much easier to understand. We can ditch Big Bang theory and, instead, accept that light is not immortal, because it ages with time. IMHO, Dipole Repeller and Shapley Attractor are muc…

It looks like we found answer to question in the original post:

Foundations of physics have not progressed in 40 years because all other alternative theories are downvoted to death.

Re: Why the foundations of physics have not progressed for 40 years

#214

Post by cygx »

shuspect wrote: post #183
SAI_Peregrinus wrote: post #177

Earlier quoted context omitted.

No, the mainstream physics reply is "It's a quantized excitation of the electromagnetic field." since that's a perfectly reasonable reply to a perfectly reasonable question.

"Height field" is mathematical model of land. Electromagnetic filed is mathematical model of what?

Electromagnetism is a U(1) gauge theory. If you take the accompanying classical geometry at face value, there's hidden state at each point in space, like some sort of dial. The absolute position of the dial is irrelevant, but the gauge potential tells you how the dial turns as you move from place to place. The electromagnetic field strength is something called curvature of the corresponding 'connection'. The mathematics are a bit involved, but morally speaking, I would say it tells you how the turning of the dial varies across space.

Re: Why the foundations of physics have not progressed for 40 years

#215

Post by konschubert »

cygx wrote: post #208
konschubert wrote: post #202

This is my pet topic, but: How can we expect to make progress in our theories if we haven’t even agreed on a consistent interpretation of today’s quantum theory?

Because explanatory stories aren't strictly necessary: While it certainly helps if we have them available because they allow us to reason intuitively, the hallmark of science is the predictive model. In contrast, a bunch of explanatory stories lacking an underlying predictive model is what we call pseudo-science.

An "interpretation of a theory" is not an "explanatory story, it's a way to map the equations ("shut up and calculate") to reality.

It's not a contested notion that every theory needs an interpretation.

Re: Why the foundations of physics have not progressed for 40 years

#216

Post by mellosouls »

orbifold wrote: post #193
mellosouls wrote: post #18

Earlier quoted context omitted.

The claim of sceptics along these lines is that string theory has produced nothing in 50 years and some string theorists appear to be in denial of that.

In science as in pretty much any other discipline you should always weigh someones opinion by their believability / credibility. The credibility of someones opinion on something is a function of their knowledge / experience of the subject and things related to it. To first approximation most sceptics have close to zero credibility making claims about string theory, as they have not produced scientific output remotely…

This sounds suspiciously like argument from authority. You will be more convincing if you address the argument, not the alleged experience of those making it.

Please see my response to the previous objection in the thread (the sibling comment to yours) requiring specific examples of progress which would silence the critics - it remains unanswered.

Re: Why the foundations of physics have not progressed for 40 years

#217

Post by mfer »

conception wrote: post #192
mfer wrote: post #167

Earlier quoted context omitted.

> I strongly disagree that the foundations of physics have not progressed for 40 years. I think, we are getting a peak at the politics of the practice of science when you look at the article and comments, like this ones parent. A bunch of this is about the unobserved. The theoretical rather than then experimentally observed (think scientific method). Whose theories get the funding to be looked into? Whose ideas are p…

I think what people miss about the industry of Science is that, logically, if a paper says "A=Foo" then we'd expect it to be true. And if another comes out that says, "A=Bar" then it's confusing, are both wrong, are both right. But instead, the way it works is a consensus is built. Researcher Bob - "We see that A=Foo." Researcher Sally -"Well, I see that A=Bar." Researcher Timmy - "Well, I see that A=Far." Researcher…

> We see that A=Foo.

I think part of this is that scientists don't "see" as in observe these things. Instead they "think that" something is the case. And, they have math and ideas to back that up.

If we had repeatable observation of the things it would be much harder to make disagreeing arguments.

Re: Why the foundations of physics have not progressed for 40 years

#218

Post by cygx »

konschubert wrote: post #215
cygx wrote: post #208

Earlier quoted context omitted.

Because explanatory stories aren't strictly necessary: While it certainly helps if we have them available because they allow us to reason intuitively, the hallmark of science is the predictive model. In contrast, a bunch of explanatory stories lacking an underlying predictive model is what we call pseudo-science.

An "interpretation of a theory" is not an "explanatory story, it's a way to map the equations ("shut up and calculate") to reality. It's not a contested notion that every theory needs an interpretation.

I would phrase things differently:

The way to map a theory to reality is via its predictions. The interpretation is how the theory fits into my mental model of reality.

In principle, reality could be strange enough that we are incapable of holding a good model of reality in our brains that evolved to avoid getting eaten by lions instead of doing quantum mechanics.

I certainly hope that's not the case, but neither can I rule it out.

Re: Why the foundations of physics have not progressed for 40 years

#219

Post by 8bitsrule »

Sometimes the impossible takes us a little longer.

US school teacher, then geologist J. Harlan Bretz spent as much time as he could 'out in the field'. It was as a result of -extensive- observations that he arrived at his 'outrageous' Missoula Floods hypothesis. He spent 40 years defending his interpretation; he remained 'out in the field' most of that time.

His critics had spent -very- little time in the field. They knew he was wrong. In 1979, he was awarded Geology's top prize.

Re: Why the foundations of physics have not progressed for 40 years

#220

Post by nonbel »

jfengel wrote: post #200
nonbel wrote: post #106

Earlier quoted context omitted.

Adding more terms sounds like more overfitting.

It sounds like that only because scientists reformulate their models in terms that people are familiar with. Actual physicists don't work in terms of the gamma correction factor; they work in tensor fields that don't look anything like conventional arithmetic. But they can pare all that down to something expressed in terms people are familiar with. And that has the bonus purpose of helping them understand why the fam…

I don't see how what you wrote could possibly address concerns with adding parameters to the model until it explains current data so perfectly that it cannot generalize to future or other data.

This is not a "theory" problem, it has to do with matching the theory to observations.

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