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xkcd #2933: Elementary Physics Paths
(imgs.xkcd.com)
Alt text:
==COSMOLOGY==> 'Uhhh ... how sure are we that everything is made of these?'
https://arstechnica.com/science/2023/01/requiem-for-a-string-charting-the-rise-and-fall-of-a-theory-of-everything/
I never seriously studied physics. A few years back I decided that it was time to push myself a little and start reading up. I started with some articles on string theory and suddenly remembered why I didn't want to study physics.
Looks like I saved twice as much time as I thought I had.
Yeah, that's a mistake.
Unless you understand the working theories out there, you gain nothing by going deep into speculative ideas.
You could try reading Feynman's lectures, he was a very passionate teacher, and he used intuition a lot, so you don't need to grind on equations to follow. https://en.wikipedia.org/wiki/The_Feynman_Lectures_on_Physics
Thanks.
You can read them for free
https://www.feynmanlectures.caltech.edu/
Thanks a second time!
String theory is barely a scientific theory, it's an untestable (experimentally) mathematical framework.
I'm far from an expert on this, but I don't think this is the best introduction to physics.
If strings are just a theory then how do you explain shoelaces? 😏
There are many kinds of 'string.'
For example, you just made a second string joke.
What are you gonna do, string me up for it?
We really should have more stringent requirements for joke quality here.
We would do that of you didn‘t keep stringing me along!
According to the article it's no longer a credible theory
It's not untestable. It gives predictions and there has been tests for those predictions. The unfortunate part is that the predictions are often not very concrete, and the range of a lot of these predictions lies far beyond our capabilities. But people are looking to measure them indirectly in various ways. So it's not like it is untestable by design or anything like that.
AFAIK, every single idea from string theory that could be tested was rejected. And the theory was made more complex, less predictive so that it could still work without the testable idea.
These are very broad statements that are not very easy to comment on. "Every single idea", makes it sound like they are a lot, I would not say they are. "Was rejected", depends what you mean... " did not show positiv results", "no longer possible to motivate economically", sure, " refuted as bullshit", not so much. "Was made more complex", sounds like there is intent, and/or, depending on what you mean by complex, that it would be necessarily a bad thing to using more advanced maths to formulate things you could not before, and hence solve new problems.
I can mention two possible avenues of inquiry that are less than 5 years old that has sprung from string theory as possible support for it: signals of black hole structure in gravitational wave 'ring downs' of black hole mergers, and the exclusion of a positive cosmological constant. But if you know that these are untestable or rejected, I'd love to hear about it.
I thought the problem with string theory is that its predictions match up with what the standard model already explains. Maybe that’s only for the things we have the capability to mature any time soon.
No, the problem is very different. In string theory you have a lot of freedom to build various models, and they can provide the standard model, slight deviations from it, or something completely different. Before LHC we knew we had some version of the standard model, the hope was that the LHC would find that we have some particular deviation, like supersymmetry (susy) with such-and-such masses and particles. It did not. The prediction is susy, the problem is that the prediction (at least yet) is not exactly this type of susy. String theory says there is supposed to be a lot of extra stuff beyond the standard model, question is just how do you find it, which is made harder by string theory allowing for so many models.
I did a semester of physics in high school and loved it. One of the few classes I actually enjoyed. I joined the nuclear program in the Navy and still loved it. I got to college and brought along all my ACE credits so I got to skip some math, physics, early chemistry, and thermodynamics.
We got to experimental physics and it broke my brain. I barely walked away with my BS and even though I could have made good money I never ended up using the degree because I ended up hating the whole field. It hangs on the wall next to my certificate from a two week bartending school.
I ended up with a long and fruitful IT career where I've never had to apply even a little knowledge I gained from that degree.
Thanks for the story.
Nice to know I'm not the only one.
Half-expected to see a wumbo boson in that article as a reason for "that" SpongeBob episode