[beckthompson]

haha I remember taking my quantum mechanics class. I thought I finally had "finished" old physics and was finally doing "newer" stuff.

In the library there were some old physics books, looked at one that was like 70 years old and it was covering the stuff we learned that quarter... Guess I have a LONG way to go until I learn "new" things xD

[sampo]

There is no new foundational physics. The standard model of particle physics is from the 1970s, and the lambda-cmd model of cosmology is from late 1990s.

Of course there is lots of new speculative ideas being produced, but it's really difficult to get anything confirmed.

[adastra22]

Quantum mechanics is not the standard model. Quantum mechanics is the stuff developed in the 20’s and 30’s. It is really useful for solving real world problems, and for that reason is what is taught to undergraduates in a “modern physics” class. It is not a correct or complete description of reality, however, and is about 50ish years out of date.

[pessimist]

The standard model is 100% quantum mechanics. It's just QM as applied to fields. While undergrads start with single or few particle quantum mechanics.

There is a lot of hard math and fundamental physical ideas that pop out when we apply quantum mechanics to fields, but it's still QM.

The work of Heisenberg, Schrodinger, Dirac, Pauli from 1925-28 or so is absolutely not our date.

[adastra22]

We are getting into definitions and common usage debates, which is the most uninteresting debate to have. I will simply state that “quantum mechanics” unqualified typically refers to the description of reality developed on Copenhagen in the 1920’s. When people are referring to quantum field theory, they are usually explicit in doing so.

[andrepd]

What do you mean? It's not "out of date", as Kepler's laws or the ideal gas law or whatever is not out of date. It's just incomplete.

Also, "modern physics" is a term of art, vs "classical physics".

[thyristan]

Every physical description of reality is correct to within some error bars. Quantum mechanics is still useful and correct, there are just more precise theories that provide refinement. And in that sense are the "current" theories if they are the most precise ones currently known.

[IAmBroom]

Not true at all. Blackbody radiation goes to infinity with Wien's distribution; error bars aren't going to get you there.

Likewise, our 1/r^2 understanding of forces goes to infinity as distance goes to zero, but we currently can't resolve that problem with error bars for the nucleus of an atom, where Heisenberg tells us any two protons can sometimes appear closer to each other than the "radius" of the nucleus.

You can't make Schottky diodes using Maxwell and error bars.

That is the entire problem: the classical models weren't merely inaccurate; they predicted completely absurd (and provably wrong) results at extreme scales.

[GoblinSlayer]

Infinite error bars.

[chermi]

What? What are the more precise theories that aren't fundamentally QM?

[GoblinSlayer]

Quantum field theory and string theory. Fundamentally they are QM, but not formally.

[hoseja]

I didn't know string theory makes any verified more precise predictions.

[volemo]

I think "new foundational [science]" is a bit of an oxymoron: theories need time to become established as foundational. There may well be ideas (currently hypotheses) that will someday be considered foundational, but we lack the hindsight and experimental validation to claim that status now.

And if you try to present your theory as foundational from the outset — like S. Wolfram does — you’ll be laughed at, much like he is.

[griffzhowl]

Hmm, I don't think so. General relativity and quantum mechanics were acknowledged as fundamental (relative to previous theories) more or less immediately, because they provided a coherent theoretical scheme that accounted for the observations which were problems for previous theories, and they also made many new predictions which were experimentally confirmed within a few years.

The problem for theoretical physics now is that all experiments from the LHC and so on are consistent with the standard model. So there are no recalcitrant observations that can guide new theory formation. The regime where we might get new physics, where gravity and QM are both significant, is so far experimentally inaccessible, though see here for a nice talk by Carlo Rovelli on one such experiment that might be plausible in the coming years: https://www.youtube.com/watch?v=tgieRctZ4dE

The problem with Wolfram/Gorrard's model is that it doesn't relate to any experiments. As far as I know the most that can be said for it is that Gorrard showed that in some limit the model is able to replicate some features of GR and QM, so that by definition doesn't go beyond the predictions of GR nor QM.

[GoblinSlayer]

>The problem with Wolfram/Gorrard's model is that it doesn't relate to any experiments

That's because quantum gravity regime is so far experimentally inaccessible?

[griffzhowl]

No, I don't think it's to do with quantum gravity. Their model makes no experimental predictions at all.

[volemo]

Fair point. Thanks for the link!

[IAmBroom]

Quibble: "Gorard".

[GoblinSlayer]

Is standard model confirmed? Then what is dark matter?

[thyristan]

In physics, there is never confirmation. At best there is "measurement agrees with the model as exactly as it is currently possible to measure". The standard model is confirmed in that sense.

Dark matter is a problem from cosmology and astronomy, that maybe has a solution in an extension to the standard model. Maybe it hasn't and that solution will come from elsewhere, maybe there is a totally cosmological explanation after all. In all cases, the dark matter problem is not a contradiction to the standard model in our current experiments. If there were a particle-physics explanation to dark matter, it would be a sufficiently small alteration to the standard model that our current experiments couldn't tell the difference, to within experimental error. That's how confirmation and new models in physics work.

[ks1723]

One of the major problems with dark matter and dark energy is, that the standard model has been experimentally confirmed to such high precision. All possible extensions proposed so far which tried to explain dark matter /dark energy have been basically falsified by the experiments.

The standard model is so descriptive and accurate, there is just no room for extensions which predict new physics but are still consistent with existing data.

[griffzhowl]

I don't believe all possible extensions have been ruled out: e.g. right-handed neutrinos are still a viable dark matter candidate as far as I know, and these are in fact motivated by the standard model, because every other fermion has both right and left chiral forms.

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

[dave333]

So likely dark matter is a different flavor of something already in the model. Dr. Mills' Hydrino theory presents hydrogen with the electron in a lower orbit that does not radiate as a candidate for dark matter. These states are stable like the ground state. Transition into or between hydrino states emit light in the UV or soft X-ray wavelengths that is not seen in optical telescopes.

https://brilliantlightpower.com/atomic-theory/

[IAmBroom]

Why isn't this mysterious state of hydrogen detectable in tests?

The page you link to is essentially a big list of links. Useless.

I am immediately suspicious of anyone who generates buzzwords to describe their theory. Heck, he even registered "hydrino" as a trademarked term.

I'm not saying he's wrong. I'm saying he walks like a duck, sounds like a duck, wears feathers and swims all day in a lake.

[dave333]

There are many ways Mills claims to have experimentally verified the existence of hydrinos but the most obvious one is the faster than hydrogen transit through a gas chromatograph.

[jojobas]

Obligatory

https://xkcd.com/2035/

[GoblinSlayer]

Intuitively speaking, if dark matter interacts only with gravitational field, then it's not affected by most standard model symmetries. A field bubble, so to say. Tachyons are somehow thought of as possible, meaning standard model doesn't say much about them?

[pantalaimon]

IIRC there has been no confirmation yet that dark matter actually exists - it might as well be true that our model of cosmology is wrong.

[vadansky]

Dark matter is the worst model, except for all those other models that have been tried from time to time.

[DebtDeflation]

>what is dark matter?

I suspect in the end it will turn out to neither be exotic new particles nor modifications to gravity, but rather that there is something fundamental about large scale structure formation in the universe that we just do not understand at the present.

[mr_mitm]

How can insights into large scale structure formation help explaining galaxy ration curves, lensing observations or barionic acoustic oscillations?

[pantalaimon]

the late 1990s is actually fairly recent

[HPsquared]

I remember thinking calculus was this modern high-tech thing in high school.

[jebarker]

I also remember excitedly telling my friends about derivatives when I first learned of them thinking that this really was cutting edge math