Why is Hilbert not the last universalist?

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In summary: The multiplication law is replaced by a composition law. It is hard to believe, that P. did not know, that the composition of loops is associative and that there exists a neutral element. It was proved 1908 by Dehn, that the fundamental group is not commutative. P. was not interested in this question." (Dieudonné, p. 643)So, in summary, while Poincaré is often considered the last universalist mathematician, Hilbert's knowledge of math was also quite universal. However, Poincaré may have had a more comprehensive understanding due to his focus on intuition rather than strict logic. Additionally, it is possible that mathematics at the time was not developed enough for P
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It is often said that Poincare was the last universalist, i.e. the last mathematician who understood more-or-less all mathematics of his time. But Hilbert's knowledge of math was also quite universal, and he came slightly after Poincare. So why was Hilbert not the last universalist? What branch of math he didn't understood sufficiently well to deserve this title?
 
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  • #3
fresh_42 said:
What about Erdös?
If we can prove that Hilbert was not a universalist, then, by induction, it is trivial to prove the same for von Neumann, Erdos, or anybody else who came later. :biggrin:
 
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  • #5
fresh_42 said:
Yes, but what if I can prove, that Hilbert was a universalist?
First prove it, and then I will tell you what then! :-p
Or perhaps you are trying a reductio ad absurdum? Let as assume that Hilbert was a universalist and derive a contradiction!
 
  • #6
To get serious again. I think the most crucial part of the question is, what really has been known at the time. I've never met Hilbert's name along with the algebraic part of Lie Theory, and similar with algebra (ring or group theory) in general. On the other hand, I have few doubts, that he was aware and knowing of the stuff, which makes it even harder to tell. And what about Russell's work? Hilbert's program is somehow the opposite of what became Gödel's theorems and Russell and others had already pointed out the right direction. It always reminds me on Descartes and on determinism. (On the other hand, I just saw Laplace and Planck on a Wiki list of representatives of determinism - two names we associate with probability nowadays. What an irony!)

So maybe Hilbert just doesn't count as universalist, because all the modern aspects of what revolutionized physics and mathematics in the 20th century were already founded to some extend, and authors, who characterize scientists in such a way, simply didn't took the effort of a closer look.
 
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Maybe Hilbert's problem was that he lived too long, while Poincare died relatively young:
Poincare: 1854-1912
Hilbert: 1862-1943
A lot of new mathematics happened from 1913-1943, which Poincare didn't need to bother with.
 
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  • #8
Demystifier said:
Maybe Hilbert's problem was that he lived too long, while Poincare died relatively young:
Poincare: 1854-1912
Hilbert: 1862-1943
A lot of new mathematics happened from 1913-1943, which Poincare didn't need to bother with.
Good point.

And I have to adjust my previous comment a little bit. Hilbert did come up in the context of Lie Theory, even though rather indirect. However, Hilbert actively supported his assistant on various occasions and against all odds of the main political stands of his time. This assistant has been definitely well aware of Lie Theory and also Ring Theory, so it's quite unreasonable to assume Hilbert was not. Her name: Emmy Noether. This supports your opinion of a universal mathematician. And even his program, although driven by an impossible aim, influenced others like von Neumann and Gödel, which has to be taken into account, too.

This let's me ask: Where have you read, that Poincaré had been the last universalist? Was it a French author?
 
  • #9
fresh_42 said:
This let's me ask: Where have you read, that Poincaré had been the last universalist? Was it a French author?
I don't know, I have seen it at a dozen of places, including wikipedia.
 
  • #10
Hi,

Demystifier said:
A lot of new mathematics happened from 1913-1943, which Poincare didn't need to bother with.

yes this can be a remarkable reason but I think there is another, Poincaré refuses to see mathematics as a branch of logic (as happened from Russel and Hilbert ) he belived that intuition was the life of mathematics.
I believe that this happroach much "malleable" allowed him to create a big personal knowledge in the fields where he contributed (these goes from numerical analysis to the group theory and all mathematics), in this sense it is considered the last Universalist...

Ssnow
 
  • #11
Ssnow said:
yes this can be a remarkable reason but I think there is another, Poincaré refuses to see mathematics as a branch of logic (as happened from Russel and Hilbert ) he belived that intuition was the life of mathematics.
I believe that this happroach much "malleable" allowed him to create a big personal knowledge in the fields where he contributed (these goes from numerical analysis to the group theory and all mathematics), in this sense it is considered the last Universalist...
Hmm, that's an interesting argument. Essentially, you are saying that if you base your reasoning on intuition rather than strict logic and axiomatics, then it is easier to comprehend the whole of mathematics. That makes sense (even though my avatar might not agree :wink:), but how about logic itself? As a universalist, did Poincare understood well the mathematical logic of his time and did he contributed to it? And if he didn't, then was he really a universalist?
 
  • #12
Demystifier said:
As a universalist, did Poincare understood well the mathematical logic of his time and did he contributed to it? And if he didn't, then was he really a universalist?
When I read about Poincaré in Jean Dieudonné's book on the history of mathematics (1700-1900), I cannot avoid the impression, that mathematics at his time hasn't been developed sufficiently, to speak of the kind of rigor and therewith logic, we demand today - a point of view which is hardly to accept, considering all the other geniuses until then (Euler, Gauss, Kummer, Legendre, Lagrange, etc.). Or the other possibility would be, that he gave a da.. about precision but had brilliant ideas, others worked out later on. That's commonly a good start to be called a "universalist".

E.g. Poincaré and the fundamental group:
"The composition of loops doesn't appear by P. (He called them routes, because to him loops have been routes which were successively walked through in both directions.) The group is defined by substitutions of certain values into (not uniquely defined) functions on the manifolds, inspired by the automorphisms in function theory, especially those which P. called Fuchs' functions, which we call automorphic functions today. The homotopy wasn't described by P. ... The role of a basis point wasn't mentioned at all ..."

Not very trustful, and Dieudonné was French, too! The short biography in this book also says: "Poincaré was a full mining engineer and also practiced this profession during his dissertation." - Maybe he thought he has dug deep enough. :cool:
 
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  • #13
fresh_42 said:
When I read about Poincaré in Jean Dieudonné's book on the history of mathematics (1700-1900), I cannot avoid the impression, that mathematics at his time hasn't been developed sufficiently, to speak of the kind of rigor and therewith logic, we demand today - a point of view which is hardly to accept, considering all the other geniuses until then (Euler, Gauss, Kummer, Legendre, Lagrange, etc.). Or the other possibility would be, that he gave a da.. about precision but had brilliant ideas, others worked out later on. That's commonly a good start to be called a "universalist".

E.g. Poincaré and the fundamental group:
"The composition of loops doesn't appear by P. (He called them routes, because to him loops have been routes which were successively walked through in both directions.) The group is defined by substitutions of certain values into (not uniquely defined) functions on the manifolds, inspired by the automorphisms in function theory, especially those which P. called Fuchs' functions, which we call automorphic functions today. The homotopy wasn't described by P. ... The role of a basis point wasn't mentioned at all ..."

Not very trustful, and Dieudonné was French, too! The short biography in this book also says: "Poincaré was a full mining engineer and also practiced this profession during his dissertation." - Maybe he thought he has dug deep enough. :cool:

While mathematics today demands rigor in proofs, mathematicians still believe that rigor is an afterthought and that ideas come first - proofs later. So Poincare's intuition is still considered the well spring of mathematical ideas.

To illustrate, I once sat in on a course in "Elementary Topology" taught by Dennis Sullivan in which he would ask students to give proofs at the blackboard. If the student would try to present a rigorous deduction, Sullivan would get angry and say "That's not a proof!" and he was not satisfied until the student explained his intuition for what was going on.

Science still does not understand the process by which new ideas and insights arise in consciousness. It may be that intuition and insight can be reduced to an unconscious computation. But it is certainly false that we experience new ideas as paths of deduction. Deduction is always an afterthought not a source.

- In most sciences e.g. biology or astronomy, the 20'th century saw a proliferation of new knowledge that made it impossible for any single person to understand everything in his field. The same is true in modern mathematics. Today mathematicians are relative specialists. On the other hand, the amount of knowledge that a modern geometer or algebraist has at his fingertips probably dwarfs the entire mathematical knowledge of Poincare or Hilbert.
 
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  • #14
Demystifier said:
but how about logic itself? As a universalist, did Poincare understood well the mathematical logic of his time and did he contributed to it? And if he didn't, then was he really a universalist?

These are good questions. I don't have answer for each of these questions but we can analyze the situation at the Poincaré time. First the branch of mathematics called mathematical-logic at the Poincaré time was just at the beginning, so still impossible to contribute in this field of mathematics (if are not the creator)... I think that the Logic considered until Russel was properly confined in the philosophy with no much connection with the world of mathematics (with this I don't want to say that mathematician didn't know the logic obviously but only that its connection with mathematics was not so enthusiastic :smile:).
I mean to say that the rigorous treatment and organization of mathematics only started in this time so the major part of mathematicians were not only mathematicians but they did a lot of works as engineers,legislators, and so on ... the mathematics was a large collection of results (sometimes caotical) obtained by thinking on real or ideal problems. I think that Poincaré was the last Universalist because without the rigorous organization of the mathematics that we have at recent days he was able to give contributions in all fields of mathematics (of its time) only using the intuition (and observation) as guideline ...
 
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  • #15
When was that said first? If it was while Poincare was still alive or just after his death, then it may be because of that.

fresh_42, I'd say that Hilbert was quite big in algebra, especially if you consider commutative algebra and algebraic number theory. There quite a few theorems there that are knows as Hilbert's theorem. On the other hand it seems that Poincare wasn't much of an algebraist.

By the way how much knowledge/expertise in an area of mathematics is sufficient for universalism? For example from the list of books authored by Lang, one may argue that he was also an universalist. Or is more depth needed in each subfield?
 
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  • #16
lavinia said:
While mathematics today demands rigor in proofs, mathematicians still believe that rigor is an afterthought and that ideas come first - proofs later. So Poincare's intuition is still considered the well spring of mathematical ideas.
Oh, I don't want to play down the role of ideas nor their importance. A friend of mine once said: "A genius is not the one with a brilliant idea late at night. It's the one who sits down the next morning and works it out." I think there is much truth to it.
 
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  • #17
fresh_42 said:
Oh, I don't want to play down the role of ideas nor their importance. A friend of mine once said: "A genius is not the one with a brilliant idea late at night. It's the one who sits down the next morning and works it out." I think there is much truth to it.

Formal rigor as now required does not have much to do with genius IMO. As you said in your post, there were many geniuses before the advent of formal proofs. It is possible to " work it out"with out reducing the problem to a syllogism. Much of "doing the work" is finding new ideas that elucidate the original idea to be proved. It is not finding formal demonstrations per se. For instance, attempts to prove the Poincare conjecture inspired entire new areas of mathematics. The same goes for research on Fermat's last theorem. Often different proofs of the same theorem employ new and entirely different techniques. These techniques are just as important or maybe more important than the theorem itself.

- There is a paper by Witten that did not contain formal proofs but spurred an intense area of research. For years mathematicians did not know whether his claimed theorems were actually true.

- I was once told about a mathematician who hardly every published but was so insightful that other mathematicians wanted to have him around just to talk to.
 
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  • #18
martinbn said:
For example from the list of books authored by Lang, one may argue that he was also an universalist. Or is more depth needed in each subfield?
Writing textbooks is one thing, making new original contributions is another. Did Lang made original contributions in all these branches of math? And for that matter, did Bourbaki made original contributions in all branches of math?

Which reminds me of a joke:
Why did Bourbaki stopped writing books? Because they realized that Lang is a single person.
 
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  • #19
That's why I asked about the criteria. So an universalist is not some one who knows "everything" in his subject, but some one who has original contribution to all subfields of his subject. I don't know if that disqualifies Lang (most likely it does), but does Poincare fit in this definition?
 
  • #20
http://www.abelprize.no/c53720/binfil/download.php?tid=53562

Here is an incomplete list of the areas of mathematics where Milnor has made stunning contributions..

- Differential Topology - many contributions including the discovery of exotic 7 spheres
- Combinatorial Topology - Counterexample to the Hauptvermutung, invention of micro bundles
- Algebra - group theory, Algebraic K-theory
-Dynamical Systems
- Knot theory - Discovered Milnor invariants.
- Characteristic classes
- Differential Geometry - Total curvature of knots
- Algebraic Geometry - Singularities of Complex hyper surfaces - Milnor fibrations

Milnor is also a great teacher and his books have become bibles for certain subjects.

In this modern world of specialization in Mathematics, Milnor had broad influence in many areas. He has been called "The Mozart of Mathematics"
 
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I didn't know that Milnor worked on dynamical systems. :smile:
 
  • #22
martinbn said:
but does Poincare fit in this definition?
That's what I would also like to know.
 
  • #23
Demystifier said:
I didn't know that Milnor worked on dynamical systems. :smile:

this is from the Wikipedia article on him

Milnor's current interest is dynamics, especially holomorphic dynamics. His work in dynamics is summarized by Peter Makienko in his review of Topological Methods in Modern Mathematics:

It is evident now that low-dimensional dynamics, to a large extent initiated by Milnor's work, is a fundamental part of general dynamical systems theory. Milnor cast his eye on dynamical systems theory in the mid-1970s. By that time the Smale program in dynamics had been completed. Milnor's approach was to start over from the very beginning, looking at the simplest nontrivial families of maps. The first choice, one-dimensional dynamics, became the subject of his joint paper with Thurston. Even the case of a unimodal map, that is, one with a single critical point, turns out to be extremely rich. This work may be compared with Poincaré's work on circle diffeomorphisms, which 100 years before had inaugurated the qualitative theory of dynamical systems. Milnor's work has opened several new directions in this field, and has given us many basic concepts, challenging problems and nice theorems.[5]
 
  • #24
lavinia said:
In this modern world of specialization in Mathematics, Milnor had broad influence in many areas. He has been called "The Mozart of Mathematics"

Why Mozart and not Beethoven? :biggrin:
 
  • #25
Maybe he was lacking in some areas of applied math. Poincare made contributions to Mining engineering, and while he never practiced it, to the best of my knowledge anyway, Von-Neumann was a qualified Chemical Engineer.

To me a polymath is a better classification. Both Poincare and Von-Neumann were polymaths of the highest order. Any other great polymaths after Von-Neumann - don't know.

I however have to say Terry-Tao seems to pretty much jump easily from area to area. Is he a polymath? Probably not.

Thanks
Bill
 
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  • #26
Demystifier said:
Hmm, that's an interesting argument. Essentially, you are saying that if you base your reasoning on intuition rather than strict logic and axiomatics, then it is easier to comprehend the whole of mathematics. That makes sense (even though my avatar might not agree :wink:), but how about logic itself? As a universalist, did Poincare understood well the mathematical logic of his time and did he contributed to it? And if he didn't, then was he really a universalist?

From a history of mathematics point of view, the (pre)intuitionist philosophy that Poincaré employed seems indeed to play a great deal in this. Its pretty clear that pretty much none of the universalists (Newton, Bernoulli, Euler, Gauss etc) before Frege et al. worked extensively on logic, with Leibniz being the exception. In this sense the logicist philosophy, and especially formalism championed by Hilbert, are really modern phenomena, i.e. a departure from classical pure mathematics.

Ironically, many modern mathematicians, heavily influenced by being educated in logicist/formalist programmes, seem to view non-rigorous, non-proof driven mathematics in a similar manner as how the classical purists viewed applied mathematics, and that while not necessarily having any disdain for applied mathematics either given that it can be treated rigorously.

It therefore seems that the universalist/specialist categorisation is a more accurate way of categorising mathematicians and their philosophies, especially those who straddle the two eras such as Poincaré and von Neumann, and comparing them with other mathematicians while taking other differences of both classical and modern mathematicians into account (such as being more purist/applied).

In this sense Poincaré clearly was more of a universalist, while Hilbert, despite being from the same era and having worked in many branches, has much more in common with modern mathematicians who are practically all specialists.
 
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  • #27
Hilbert is quite famous for his algebraic work on invariant theory. In fact some say his work gave birth to the subject of abstract algebra, as opposed to computational methods in algebra of the 19th century. David Mumford famously resurrected ideas and techniques of Hilbert to develop what he calls Hilbert's criterion for "stability", a crucial technique for constructing moduli spaces in algebraic geometry. A fundmental object used for constructing such moduli spaces developed by Grothendieck is the so called "HIlbert scheme". Most of us encounter first the more elementary algebraic result due to Hilbert that a polynomial ring over a so called "Noetherian" ring is also Noetherian. One of the classic algebraic works on my shelf is (a translation of) Hilbert's theory of algebraic number fields. According to its introduction, this was the key text on the subject for some 30 years at the beginning of the 20th century, and that the famous algebraists Artin, Hasse, Hecke, and Weyl all learned algebraic number theory from it. Some 70 years later Lang is also said to have attributed the structure of his own book to this source. Hilbert's presentation of his famous problems about 1900 clearly demonstrates his large scale grasp of the mathematics of his time. These problems influenced the progress of mathematics for decades afterwards.

Here is a link on invariant theory:

https://en.wikipedia.org/wiki/Invariant_theory

and another on Hilbert's problems, several about algebraic and analytic number theory, and the famous 5th problem on topological versus lie groups.
 
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  • #28
Alexander Grothendieck, a remarkable man famed nearly as much for insanity as his contributions to mathematics, is a worthy contender, but, John von Neumann stands out in any crowd of mathematicians.
 
  • #29
Another point is that all universalists up to and including Poincaré were clearly not only mathematicians but also specifically physicists during practically their entire careers; apart from the indirect mathematical role of Hilbert space in von Neumann's QM and the Einstein-Hilbert action in GR, I am not aware of any other direct contributions to physics proper from Hilbert.

I would even go as far as to say that Hilbert's purist mathematical stance and constant formalist want for axiomatization is as anti-physics as it gets; moreover, I presume Feynman shared this opinion based on his Messenger Lecture on the relation of mathematics to physics.
 
  • #30
Auto-Didact said:
Another point is that all universalists up to and including Poincaré were clearly not only mathematicians but also specifically physicists during practically their entire careers; apart from the indirect mathematical role of Hilbert space in von Neumann's QM and the Einstein-Hilbert action in GR, I am not aware of any other direct contributions to physics proper from Hilbert.

I would even go as far as to say that Hilbert's purist mathematical stance and constant formalist want for axiomatization is as anti-physics as it gets; moreover, I presume Feynman shared this opinion based on his Messenger Lecture on the relation of mathematics to physics.

Following up on your post I started to listen to the Messenger Lecture. I think Feynman was talking not about mathematics per se but about the application of mathematics to physical problems.

Mathematicians examine the realm of mathematics much as physicists examine nature. As Feymann described for Physics, Mathematics also has need for the "Babylonian method" as he called it.
 
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  • #31
lavinia said:
Following up on your post I started to listen to the Messenger Lecture. I think Feynman was talking not about mathematics per se but about the application of mathematics to physical problems.

Mathematicians examine the realm of mathematics much as physicists examine nature. As Feymann described for Physics, Mathematics also has need for the "Babylonian method" as he called it.

Did you watch the entire thing? I think it is pretty clear that physics both historically and today cannot work solely based on axioms, as mathematics does, because we do not have a complete theory of physics yet. This also means that we do not know today which axioms ultimately will turn out to be truly fundamental in physics, being able to derive the whole of physics from them.

The standard method in physics is definitely not to work from axioms as it is in modern mathematics, even if this could in principle be done (e.g. see the Wightman in axiomatic quantum field theory), because the most important thing for something to be called physics is to have the predictions match experiment; in mathematics this feature does not really exist.

I could go much further and in much more depth on these topics, but I think this all is getting way off-topic. To get back on topic: pure mathematicians have, and always have had, a disdain for anything applied, believing it to be beneath them; it goes without saying that this disdain extends to all of physics as well. Hilbert clearly agreed with this stance for pretty much his entire life. For Poincaré however, like Newton and Gauss before him, this purist view of all things could not be further removed from the truth.
 
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  • #32
Auto-Didact said:
Did you watch the entire thing? I think it is pretty clear that physics both historically and today cannot work solely based on axioms, as mathematics does, because we do not have a complete theory of physics yet. This also means that we do not know today which axioms ultimately will turn out to be truly fundamental in physics, being able to derive the whole of physics from them.

The standard method in physics is definitely not to work from axioms as it is in modern mathematics, even if this could in principle be done (e.g. see the Wightman in axiomatic quantum field theory), because the most important thing for something to be called physics is to have the predictions match experiment; in mathematics this feature does not really exist.

I could go much further and in much more depth on these topics, but I think this all is getting way off-topic. To get back on topic: pure mathematicians have, and always have had, a disdain for anything applied, believing it to be beneath them; it goes without saying that this disdain extends to all of physics as well. Hilbert clearly agreed with this stance for pretty much his entire life. For Poincaré however, like Newton and Gauss before him, this purist view of all things could not be further removed from the truth.

IMO mathematics does not work from axioms. Axioms are always an after thought - like physical laws.

To me, physics is in fact a deductive system and what physicists do is search for the best set of axioms to explain Nature. For example: Axiom: The speed of light is the same in all inertial reference frames. Deduction: Relativity of simultaneity.

Mathematicians generally work empirically and through intuition and by Feynmann's "Babylonian Method" which looks at many examples and then derives a theory that reveals common properties. In this sense, it is very much like physics or any other science.

Euclidean geometry itself is an after thought of long research and the study of flat spaces goes far beyond Euclid's Axioms.

- Mathematics is not complete either. There are many unsolved problems with no known method of resolution.
 
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  • #33
Here is the section on Hilbert's work on Physics from the Wikipedia article "David Hilbert" At the end of the article, the Book "Mathematical Methods of Physics" by Courant and Hilbert is mentioned . It is an attempt to bring Mathematics and Physics together as is explicitly stated in the introduction.

"Physics[edit]
Until 1912, Hilbert was almost exclusively a "pure" mathematician. When planning a visit from Bonn, where he was immersed in studying physics, his fellow mathematician and friend Hermann Minkowski joked he had to spend 10 days in quarantine before being able to visit Hilbert. In fact, Minkowski seems responsible for most of Hilbert's physics investigations prior to 1912, including their joint seminar in the subject in 1905.

In 1912, three years after his friend's death, Hilbert turned his focus to the subject almost exclusively. He arranged to have a "physics tutor" for himself.[37] He started studying kinetic gas theory and moved on to elementary radiation theory and the molecular theory of matter. Even after the war started in 1914, he continued seminars and classes where the works of Albert Einstein and others were followed closely.

By 1907 Einstein had framed the fundamentals of the theory of gravity, but then struggled for nearly 8 years with a confounding problem of putting the theory into final form.[38] By early summer 1915, Hilbert's interest in physics had focused on general relativity, and he invited Einstein to Göttingen to deliver a week of lectures on the subject.[39] Einstein received an enthusiastic reception at Göttingen.[40] Over the summer Einstein learned that Hilbert was also working on the field equations and redoubled his own efforts. During November 1915 Einstein published several papers culminating in "The Field Equations of Gravitation" (see Einstein field equations).[41] Nearly simultaneously David Hilbert published "The Foundations of Physics", an axiomatic derivation of the field equations (see Einstein–Hilbert action). Hilbert fully credited Einstein as the originator of the theory, and no public priority dispute concerning the field equations ever arose between the two men during their lives.[42] See more at priority.

Additionally, Hilbert's work anticipated and assisted several advances in the mathematical formulation of quantum mechanics. His work was a key aspect of Hermann Weyl and John von Neumann's work on the mathematical equivalence of Werner Heisenberg's matrix mechanics and Erwin Schrödinger's wave equation and his namesake Hilbert space plays an important part in quantum theory. In 1926 von Neumann showed that if atomic states were understood as vectors in Hilbert space, then they would correspond with both Schrödinger's wave function theory and Heisenberg's matrices.[43]

Throughout this immersion in physics, Hilbert worked on putting rigor into the mathematics of physics. While highly dependent on higher math, physicists tended to be "sloppy" with it. To a "pure" mathematician like Hilbert, this was both "ugly" and difficult to understand. As he began to understand physics and how physicists were using mathematics, he developed a coherent mathematical theory for what he found, most importantly in the area of integral equations. When his colleague Richard Courant wrote the now classic Methoden der mathematischen Physik (Methods of Mathematical Physics) including some of Hilbert's ideas, he added Hilbert's name as author even though Hilbert had not directly contributed to the writing. Hilbert said "Physics is too hard for physicists", implying that the necessary mathematics was generally beyond them; the Courant-Hilbert book made it easier for them"
 
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  • #34
Thanks for the above quote, I had already read it, but it is certainly useful here for others as well.

lavinia said:
IMO mathematics does not work from axioms. Axioms are always an after thought - like physical laws.

To me, physics is in fact a deductive system and what physicists do is search for the best set of axioms to explain Nature. For example: Axiom: The speed of light is the same in all inertial reference frames. Deduction: Relativity of simultaneity.

Mathematicians generally work empirically and through intuition and by Feynmann's "Babylonian Method" which looks at many examples and then derives a theory the reveals common properties. In this sense, it is very much like physics or any other science.

Euclidean geometry itself is an after thought of long research and the study of flat spaces goes far beyond Euclid's Axioms.

- Mathematics is not complete either. There are many unsolved problems with no known method of resolution.

I agree with much of what you say; the point is not that mathematicians always do try to axiomatize and prove things, it is that they can at all and in many modern instances do. As for physics being deductive, I agree up to a point: the problem in physics is that the 'axioms' need to be experimentally verified before being justifiable as an axiom i.e. as a 'self-evident truth'; I would argue no such thing exists in physics, there are instead principles and postulates. Postulates and principles in physics can be rendered wholly defunct if they get experimentally falsified; their derivations are then pretty much worthless for physics since they never were true to begin with, let alone self-evident. I would also argue physics is more abductive (i.e. guesswork, estimation) than deductive as Feynman also said in one of last his Messenger Lectures describing how to do new science.

And of course mathematicians still also calculate things and do other conventional things, but proof has become a major part of any real mathematics programme, focusing on axioms and how to prove theorems thereby. One example is the mature linear transformation view in linear algebra which heavily abstracts away from vectors and can be applied to basically anything which satisfies the vector space axioms, another is the focus on methods of proof and definition of continuity, smoothness and analyticity as taught in analysis courses.

As Feynman points out, this extemely abstract and rigorous attitude marks a very great departure in the very meaning and goal of what historically was important in mathematics, and it was not really there at all for physicists and mathematicians before the 20th century; indeed, it was even the reason he changed his major from mathematics to physics. Incidentally, after logicism and formalism arose and physics simultaneously underwent it's two early 20th century revolutions, mathematics and physics, once very close subjects started to stray further and further apart; Dyson writes a bit on this in his paper 'Missed Opportunities' in the analogy of a marriage and a divorce. Last but not least, it may be that since Feynman's time studying mathematics in university has changed a bit focusing a bit less on axioms than before after the whole debacle with the Continuum Hypothesis being independent of certain axiomatizations of mathematics.
 
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  • #35
More on-topic: a few years ago I read Poincaré's seminal book, The Foundations of Science. In it, he clearly discusses his mathematical views while carefully separating his views from the logicians and logicists.

Another such seminal work is Philosophy of Mathematics and Natural Science by Weyl. Here is my favourite quote:
Hermann Weyl said:
Mathematics with Brouwer gains its highest intuitive clarity. He succeeds in developing the beginnings of analysis in a natural manner, all the time preserving the contact with intuition much more closely than had been done before. It cannot be denied, however, that in advancing to higher and more general theories the inapplicability of the simple laws of classical logic eventually results in an almost unbearable awkwardness. And the mathematician watches with pain the greater part of his towering edifice which he believed to be built of concrete blocks dissolve into mist before his eyes.

Incidentally, I would also argue that Weyl, who was a student of Hilbert, comes close to being a universalist as well.
 

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