A Century of Quantum Mechanics
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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
Of course there is lots of new speculative ideas being produced, but it's really difficult to get anything confirmed.
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.
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.
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.
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.
Also, "modern physics" is a term of art, vs "classical physics".
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.
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.
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.
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.
That's because quantum gravity regime is so far experimentally inaccessible?
Quantum mechanics started with the description of electron orbitals around an atom; how they work is the foundation of chemistry.
It got out of labs in a quite spectacular way in the summer of 1945, eighty years ago.
No; they didn't really need it.
Yes. Nuclear reactions require understanding and modeling of the strong force, you can't understand or even see what protons and neutrons are without understanding the strong force. The mixture of positively charged and neutral particles being stuck together with enormous force which essentially does not exist at all outside of the nucleus of an atom. (there is more than three pounds of force between every pair of protons inside every nucleus with the strong force counteracting the electrostatic force)
You couldn't design a bomb without being able to model the strong force and you couldn't get to that point of investigating the atom without coming up with QM.
You couldn't get the idea of isotopes and enriching U-235 to U-238 or transmuting uranium to plutonium without understanding QM.
Or the circumstances that would lead someone to blindly creating a controlled nuclear reaction without coming up with QM in the process would be pretty absurd.
The idea for the bomb came from the understanding of the strong force. Step one: notice that there's a crazy powerful force keeping positively charged particles stuck together in the nucleus. Step two: the eureka moment of realizing you can "release" that force by causing a chain reaction of fission in heavy elements.
The roads?
Well obviously the roads go without saying!
Like we can imagine some kind of purely deterministic thing going on but when the rubber meets the road the best ways of working stuff out seem to very strongly imply some fundamental indeterminism. No one likes it, but thats the way it is.
I've been to phil. physics conferences and I've never encountered anyone who has any kind of strong attachment to nondeterminism. In fact, in general, I think almost every physicist who learns QM has a prejudice against it which never entirely goes away unless they get deep into foundations which forces a more detached perspective.
But it's the opposite, all people with shallow understanding of QM believe in indeterminism, because it's the first thing they learn from the start, and then this belief ossifies. Oh and Heisenberg uncertainty principle tells you that reality is unreal. Conversely foundations are deeply mathematical with basically nothing uncertain or random is sight. In fact it's foundations that have bias for mathematics and determinism. How do you interpret the evolution operator as random?
From the point of view of foundations of physics there really is no easy way out of this apparently fundamental randomness. We can be wave-function substantivalists and then we must explain why and how we don't see wave functions but concrete outcomes. We can adopt t'Hooft's cellular automata interpretation but that framework cannot easily support even something as simple as basic interactions in QFT (last I checked). We may list any number of ways of interpreting QM but all of them that I know of only at most banish randomness to the initial conditions, but not totally eliminate it from the ontology.
I'm not saying that reality is fundamentally non-deterministic. But I am saying that most of the ways one squares basic quantum mechanical predictions with basic physical measurements suggest a type of uncertainty that is at least very close to being "fundamental."
Outcomes of observation are explained by linearity of evolution operator and decoherence, but then you get human factor: different people have different problems with this explanation, I think it's because unitary motion is unintuitive, Aristotle knew explanation of heliocentrism, but it didn't work, because geocentrism was more intuitive for him. Some apparently suggest that to explain human experience you need to calculate mind from physics, which needs to solve the hard problem of consciousness, which is impossible.
Jeez - HN is brutal. Even a bot could have understood the context I meant.
“To celebrate 100 years of quantum mechanics, the CERN Courier looks back at the impact of this theory and examines how it keeps delivering new puzzles, experimental ideas and technologies.”
the following comment may be completely misguided but I didn’t find it offtopic (maybe offreality):
“This is probably the slowest branch of the sciences, not able to get out of labs even after a century.”
But now I see that the author says that he meant quantum computing so the comment makes even less sense and is indeed slightly offtopic.
Good on-topic subthreads usually show some sign of contact with the body of the article—not just the title, and certainly not the most generic phrase (in this case "quantum mechanics") that can be abstracted from the title.
But one can always argue particular cases either way and I agree that the counter-argument was stronger for that one.