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Comment by cjfd | Hacker News Reader

Actually, string theory arose as a way of doing exactly what this person requests. It was noticed that quantum field theory and gravity do not go together, so it was attempted to do something about this. So, it did not really work out? Well, you know the thing with this kind science is that it is unknowable beforehand what you are or are not going to find.

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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 comparable to proponents of string theory. This is simply because people like Witten tower far above most other working theoretical physicists.

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.

Said skeptics are blissfully unaware of the contributions that working on string theory has made to other branches of physics and mathematics. To say it's produced nothing is to admit ignorance.

In the context of this article - physics progression - what specific theoretical discoveries or predictions has it produced that can be verified or disproven via experiment in the forseeable future?

Point was, math is one thing, reality is another.

From an outsider's point of view (i.e. mine) it looks like physics has become too enamored with mathematics, "thinking" that reality can be totally described by mathematics. Which brings us to one of the author's point of views, the fact that physicists (and I guess most scientists) nowadays dismiss things like philosophy of science or epistemology, they just continue head-on on their "quest for knowledge" not realizing that for almost half a century now nothing big has been "found out".

There's nothing wrong with the way math is used in physics. Consistency is a good thing; whether calculations possess explanatory power is another question.

I didn't say the maths is wrong, I just said it has reached its limits. And "no big discovery" for the last 40 years kind of shows that some limits have been reached.

> Consistency is a good thing

Lots of close but in the end ineffectual "epistemic" systems were internally consistent but in the long run they proved "deficient" (as in other, more efficient systems took their place). I confess I've never read Thomas Aquinas's work (to give just one example) but I'm pretty sure his "view of the world/reality system" is pretty consistent, don't think there are any internal contradictions in his writings. Problem is his internally consistent system wouldn't have been able to allow us to build combustion engines or modern electronics, so that we have had to come up with other internally-consistent "epistemic systems" that proved to be more efficient (because they allowed us to build and reason about combustion engines and modern electronics).

In the end and in the great scheme of things I don't think this theoretical physics road-block will be of any great importance for the general public, it looks like people are content with what they already can purchase based on past physics-related discoveries. Yeah, traveling through galaxy wormholes or getting to 100% know if the Universe is finite or not would be nice things to have, but people just don't care and there's nothing wrong with that.

If the past is any guide, whenever reality isn’t adequately described by mathematics we just come up with new mathematics.

I may be in the wrong here, but afaik mathematics has not "re-invented" itself after WW2, to take it a step further, I fail to see how we're doing different mathematics compared to what Newton and Leibniz have put on the table.

Even if we look at the "greatest" post-WW2 maths result, Fermat's Theory, I don't see any new reality-related insights that it has brought us, and I'll go another step further and I say that even if we were to someday prove the Riemann hypothesis I don't see how it would fundamentally bring new insights regarding "reality"/the physical world.

If anything, I dare say that in a certain way maths has tainted the physical world for us, has made us believe that in the same way in which mathematics is "homogeneous" then the physical world is too, if maths has numbers and "units" and if (1002 - 1000) = (2002 - 2000) then it also means that in the physical world we have homogenous "stuff".

This is why physics has started using mystical-like language like "elementary particles" which are seen as the "foundation of the physical world", with the implicit premise (if I'm wrong here, please correct me) that given a certain "elementary particle" (let's say a boson) then the boson close to it or the boson situated at the other "side" of the Universe are pretty much the same thing, almost identical, the same way as the mathematical difference I mentioned above is the same, or how two parallel lines are "the same".

Basically almost all the theoretical physicists have become Platonists by embracing mathematics no-questions-asked, when in fact they should have remained closer to Hume. And when reality hits them in the face pretty hard they resort to even more mysticism by "inventing" concepts like dark energy and the like.

Later edit: I see that that "homogenous reality" theory even has a name, Cosmological principle [1], and as a close-enough Hume follower Karl Popper was quick to dismiss it. By reading it you have to wonder what those physicists had in mind when they wrote it down:

> Although the universe is inhomogeneous at smaller scales, it is statistically homogeneous on scales larger than 250 million light years.

like, why 250 million is ok and 240 million light years is not ok? To say nothing of the fact that the "infinitely small" (the mystical-like elementary particles I mentioned above) are ignored completely from this discussion, they're also probably seen as "statistically the same". As I said, this "statistical sameness" has made us believe that more than half of the Universe we know of (68%, to quote Wikipedia) is made out of the mother of all mystical thingies, "dark energy".

[1] https://en.wikipedia.org/wiki/Cosmological_principle

First off, mathematics did actually reinvent itself in the late 1940s, with the discovery of Category Theory, which, despite being sometimes called “abstract nonsense”, has found its way into theoretical physics. Further, there is nothing mystical at all in any of the concepts of the modern physics - not more anyway than in the concept of, say, the atom. It is actually math that should be credited with the removal of the shroud of mysticism perceived by some - perhaps even many - of the uninitiated. (Physics is not an exception here - some people still look at a working computer as a miracle, for example.) And the homogeneity at the scales at which there’s just too many things to allow for much diversity should, too, be seen as one of the manifestation of the absence of any true mystery in the universe.

> there is nothing mystical at all in any of the concepts of the modern physics

Nothing mystical, but there certainly are deep questions, which is why we have the various interpretations of QM.

It has worked several times in the history of physics, though.

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