I On the relation between physics and philosophy

[Demystifier]

Well, the methods of theoretical physics is based on mathematics, not philosophy.

To use such a method, one doesn't need philosophy. But to discover such a method, philosophy may be of a great help.

 

[vanhees71]

Most physicists are down-to-earth, but some aren't. Newton and Einstein, for instance, weren't.

Einstein was in his younger years, and then he run into a dead end. It's the prime example of a genius mislead by philosophy!

 

[Auto-Didact]

To use such a method, one doesn't need philosophy. But to discover such a method, philosophy may be of a great help.

Exactly, this cannot be stressed enough! If one starts with mathematical methods alone then there are simply too many possible roads to choose from and progress halts, while if one starts with a purely intuitive conceptual description constrained by logical truths then there are far fewer roads to choose from; choosing the right road quickly leads to progress. All of them have to be taken individually and at the beginning of each road is where the mathematical method begins anew.

Moreover, the correct route to choose prior to using any mathematical methods can actually be known in advance, purely as a matter of having a highly developed intuition based on the experience of having done this many times before and then recognizing how to proceed through the correct usage of analogy in this purely rational endeavor of logical exploration.

Poincaré describes this method of reasoning of the scientist masterfully in Science and Method, specifically in Book 1 The Scientist and Science, Chapter 1 The Selection of Facts. The book is available here by courtesy of Google Books.

Theoretical physics is a mixture of mathematics and knowledge about the empirical facts and a lot of intuition about how to use the former to describe the latter.

The bolded part represents your misunderstanding: physics is not knowledge of empirical facts, physics is instead a form of reasoning using principles about empirical facts. Knowledge and reasoning while related are not the same thing, since the former is the thought content while the latter is the thought process.

In fact, physics is the only science which can not primarily be characterized by being merely a collection of facts but instead by being a collection of methods, i.e. not the content of knowledge but the method does physics make. No other science has this property (biology, chemistry, psychology, economics, etc) and when they do attain it they are usually reduced so completely to physics that they are called physics (cf. biophysics, econophysics, sociophysics, etc).

This is what Rutherford meant when he said"All science is either physics or stamp collecting.", with stamp collecting referring to the mere collecting of facts, i.e. the collection of knowledge. This is also what Einstein meant when he said: "[I do not] carry such information in my mind since it is readily available in books. ... The value of a college education is not the learning of many facts but the training of the mind to think."

Concrete example to drive home the point: merely knowing what the speed of sound is does not make one a physicist; instead knowing how to determine the speed of sound - especially if done purely by reasoning using intuition alone without having any prior knowledge of this topic - is what makes one a physicist.

 

[Julius Ceasar]

a logically simpler notion

One universe only, same laws of physics everywhere, you can't get something from nothing...a simple and logical place to begin looking at the cold hard data or useless philosophizing?

 

[RUTA]

Particularly there is no measurement problem related to QT from a physics point of view. To the contrary QT describes all empirical facts quantitatively with an amazing precision. Only if there were a reproducible contradiction between empirical facts and the predictions of a theory this theory would have a problem.

Weinberg agrees with those of us who see a problem http://quantum.phys.unm.edu/466-19/QuantumMechanicsWeinberg.pdf

 

[Julius Ceasar]

Weinberg agrees with those of us who see a problem http://quantum.phys.unm.edu/466-19/QuantumMechanicsWeinberg.pdf

As Werner Heisenberg realized, a particle cannot have, at the same time, both a definite position and a definite velocity.

 

[RUTA]

https://iai.tv/articles/why-physics-has-made-no-progress-in-50-years-auid-1292

 

[microsansfil]

Weinberg agrees with those of us who see a problem http://quantum.phys.unm.edu/466-19/QuantumMechanicsWeinberg.pdf

The problem seems to be primarily a problem of interpretation of the theory of quantum mechanics. Richard Feynman lamented “I think I can safely say that no one understands quantum mechanics.”.

If we adopt vanhees71's point of view, which is to see the models derived from the theory of quantum mechanics as mathematical tools exclusively intended to make predictions, then it also seems to me as vanhees71 that there is no problem.

The difficulty is to try to find, like Einstein, an unambiguous ontological interpretation of quantum mechanics :

In a 1926 letter to Born, Einstein complained: Quantum mechanics is very impressive. But an inner voice tells me that it is not yet the real thing. The theory produces a good deal but hardly brings us closer to the secret of the Old One. I am at all events convinced that He does not play dice .

We poor humans only perceive the "world" through our consciences.

Patrick

 

[julcab12]

If science is the refined version of philosophy. Are we missing something in Philosophy that scientific criteria no longer

Well said, an experiment is a brilliant supplier of data, but why do an experiment in the first place without some idea seeking an answer? We need not wonder with science, data is what it is- a cold hard fact.
I wonder about these vital facts therefore I philosophize.

Scientific method and basis is enough to go around the next step. In any problem you need to have solid basis. Science is a refined version of philosophy no more no less.

 

[julcab12]

Einstein was in his younger years, and then he run into a dead end. It's the prime example of a genius mislead by philosophy!

Well. The main philosophy of Einstien still lives and envisioned today by the likes of Ashtekar, Baez, Barrau, Rovelli etc.

 

[A. Neumaier]

The problem seems to be primarily a problem of interpretation of the theory of quantum mechanics. Richard Feynman lamented “I think I can safely say that no one understands quantum mechanics.”.

If we adopt vanhees71's point of view, which is to see the models derived from the theory of quantum mechanics as mathematical tools exclusively intended to make predictions, then it also seems to me as vanhees71 that there is no problem.

There is indeed no problem if one gives up trying to really understand quantum mechanics and only using it to make predictions.

Using something is an engineering activity and needs knowledge but no real understanding (we can use electricity without understanding how it works), understanding it a philosophical activity.

But finding the principles missing to make progress beyond applying the old needs understanding on a deeper level than the superficial engineering knowledge.

 

[Demystifier]

Einstein was in his younger years, and then he run into a dead end. It's the prime example of a genius mislead by philosophy!

We, the people on this forum, struggle over what do we mean by "ontology", but I think we don't even agree on what do we mean by "philosophy". For instance, when you say that classical electromagnetism is best understood when put in a Lorentz covariant form from the very start, for me that's an example of philosophy.

Consider the two statements:
1) Classical electromagnetism is best understood when put in a Lorentz covariant form from the very start.
2) Nonrelativistic QM is best understood when put in a Bohmian form.

I cannot imagine any precise definition of philosophy by which 2) is a philosophical statement and 1) isn't.

 

[microsansfil]

Using something is an engineering activity and needs knowledge but no real understanding (we can use electricity without understanding how it works), understanding it a philosophical activity.

What is the meaning of "understanding" ?

Finding a primitive formulation of quantum physics like the set theory which is the foundation of Mathematics or finding methaphysical beliefs to replace naive realism ?

Patrick

 

[Auto-Didact]

For instance, when you say that classical electromagnetism is best understood when put in a Lorentz covariant form from the very start, for me that's an example of philosophy.

Fully agreed.

The moment one states that the core properties of some specific concept - in this particular case, the core properties of the empirical phenomenon of electromagnetism - is best described or even fully captured by some mathematical framework - in this particular case, the Lorentz covariant formalism - they are automatically making a deep philosophical statement relating to metaphysics.

It is not an exaggeration to say that physics is predominantly concerned with exactly the making of such statements about practically all natural phenomena or nature in general, i.e. discovering the principles and seeing the relationship between those principles and even more general principles; this is done in order to understand nature.

It is very striking that in physics making such statements is taken for granted, because such statements are literally never made in any other aspect of life, let alone in the practice of any other science! Even those philosophers unfamiliar with physics do not tend to know that physics has or makes such statements; those philosophers of course either aren't physicists or they are completely unfamiliar with Kant's analysis of Newtonian physics by being trained in another tradition and never looking outside their bubble.

Moreover, once any such statement of principle can and has been made successfully, almost everything else - i.e. constructing a mathematical model, making predictions, doing experiments - follows automatically as a deductive consequence with often little to no intelligence above an average grad student level required.

Therefore, the theoretical physicist should mainly be concerned with or at least always be interested in making such statements of principle, especially w.r.t. some part of physics which hasn't been stated satisfactorily yet in such a manner, like in the case of the measurement problem in QT, because this is where there is the most for physics to gain; in any case, what should be clear as day in the case of QT is that these gains will probably not come from the side of experiment!

I end by quoting Poincaré, who said that: The scientist does not study nature because it is useful to do so. He studies it because he takes pleasure in it, and he takes pleasure in it because it is beautiful. If nature were not beautiful it would not be worth knowing, and life would not be worth living.

 

[RUTA]

Here is a look into Einstein's thinking as he formulated GR: https://www.pitt.edu/~jdnorton/Goodies/Zurich_Notebook/
You can see that he wasn't guided by "fitting data," but by particular mathematical properties that his philosophical reasoning had convinced him the theory must possess.

 

[Julius Ceasar]

The philosophical reasoning leads to an idea that should fit with the data, not the other way around. Its about accepting a truth first then coming up with an idea after, the idea did not just appear out of nowhere. I believe in the scientific method but it needs to believe there is a truth out there and stop refusing help when its needed. If you ask for nothing then that's probably what you will get.

 

[Demystifier]

Well, Feynman obviously had more fun with sex (without practical results ;-)) than with philosophy (whatever practical results one might expect or not)...

Today appeared the paper https://arxiv.org/abs/2001.05569 entitled "Foundations of Quantum Mechanics according to my teachers" beginning with the following statement:
"There are three reasons foundation of quantum mechanics are similar to sex:
1.Everyone considers herself/himself an educated amateur;
2.Professionals are treated with suspicion
And I forgot the third."

 

[A. Neumaier]

What is the meaning of "understanding" ?

Since you apparently cannot accept the dictionary meaning without asking deeper, you are doing already philosophy.

 

[Demystifier]

As Feynman said ...

Here Feynman teaches Bohmian mechanics without admitting so.

 

[microsansfil]

Since you apparently cannot accept the dictionary meaning without asking deeper, you are doing already philosophy.

I don't have a problem with philosophy or metaphysics. I became aware a long time ago that we perceive the "world" first and foremost through our consciousness (our first person experiences) and that by inter subjectivity via language we create a scientific process of objectification, in the hope of sparing the subject of the object of our study.

"It is the theory which decides what can be observed." dixit Albert Einstein. And so the subjective imprint of the subject is always present in spite of the scientific approach of objectification.

It is never Known but Is the Knower

Now the pragmatic approach "Shut up and calculate" is very useful to us.

Patrick

 

[Auto-Didact]

Here Feynman teaches Bohmian mechanics without admitting so.
View attachment 255716

Unbelievable, Bohmian Mechanics is lurking right there in full glory at the very end of the Feynman Lectures! I can't believe I missed this before, but tbh I haven't reread the Lectures since early uni days when I knew neither BM, nor hydrodynamics.

In any case, this finding deserves its own thread.

 

[vanhees71]

Here Feynman teaches Bohmian mechanics without admitting so.
View attachment 255716

Hm, and he doesn't mention that this leads to the Abelian Higgs mechanism :-(.

 

[Auto-Didact]

Hm, and he doesn't mention that this leads to the Abelian Higgs mechanism :-(.

Perhaps, even Feynman had his limits? Are you indirectly acknowledging the utility of BM? :)

 

[vanhees71]

BM is a funny curiosity working for non-relativistic QT. I don't see much merit in it compared to minimally interpreted QT, but it shows how a non-local deterministic theory compatible with non-relativistic QT looks like. As such it's interesting for some philosophers who cannot accept the indeterminism of the world, which I consider an established fact though, given the plethora of Bell tests in favor of QT, and the compatibility of relativistic local QFT with all observations. I've not seen a convincing non-local relativistic theory a la Bohm though.

 

[Auto-Didact]

I'm not talking about the Bohmian interpretation, I'm talking about the utility of equation 21.33 itself for utilization in physics generically e.g. like how Feynman is using it there. Is that equation part of physics or isn't it, in your opinion?