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New theory claims to unite Einstein's gravity with quantum mechanics

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Re: New theory claims to unite Einstein's gravity with quantum mechanics

#131

What if universality is a name for a kind of antagonism? What comes first is not a wholeness that is disturbed, but difference itself. Reality itself is unfinished and built in parallax. This new theory alongside current metaphysical theories of everything is inspiring.

Why is this comment at the top of the discussion thread?

We're talking about the validity of the mathematical theory, not new age woo-woo methaphysical theories.

Re: New theory claims to unite Einstein's gravity with quantum mechanics

#132

Earlier quoted context omitted.

Yes, he's describing evaporation. Here's a thread about it, basically the answer is "we don't know" https://physics.stackexchange.com/questions/77130/why-does-p...

Thank you, that link (particularly [1]) is basically the kind of explanation I was looking for in my initial comment. [1] https://physics.stackexchange.com/a/784886

There's so many variables there! What kind of purity could 1889 achieve? What kind of uniformity between the N samples? How do they know the different cleaning procedures (!) are not adding mass by leaving something behind? If the samples are known to be oxidizing, why leave them in air? Why are there multiple elbows in that graph around 1950 -- surely another procedural change but again not uniformly applied?

Maybe these aren't the best sources of historic mass data.

Re: New theory claims to unite Einstein's gravity with quantum mechanics

#133
post #99

After skimming the second paper, I still don't understand how precision mass measurements come into play here. They mention Cavendish-type measurements, but they are used for measuring the gravitational constant. Of course, you can turn the formula around, plug an unknown mass into the apparatus and then call it a mass measurement, but it's going to be a very imprecise measurement. A Penning trap can give you 11 to 1…

(I went to a talk by Oppenheim author a couple weeks ago on this topic.) The idea is that gravity, as a force, only operates classically. More precisely: there is a classical state describing the curvature of space time, and then a quantum state describing the configuration of particles on that spacetime. But then, that quantum state needs to affect the classical state again (mass bends space), which would usually le…

So if I am understanding this correctly:

Quantum particles can effect change (curve) spacetime without direct quantum action if you sprinkle a bit of randomness into the (quantum acting on spacetime) effect?

Re: New theory claims to unite Einstein's gravity with quantum mechanics

#134

Earlier quoted context omitted.

Can you give any examples of times you’ve easily anticipated X when a whole field of subject matter experts have demonstrably overlooked it?

This isn't to agree with the parent comment, but wouldn't this situation itself be an answer to your question (assuming the claim is true)? Laymen like me easily anticipated mass divergence, but purportedly scientists have been surprised by it.

The procedure of multiple weights being calibrated against a single standard is _predicated_ on anticipated mass divergence.

The mystery being discussed is that, even after the obvious sources of error are allowed for, there is still a discrepancy, and it's not easy to determine how much of that discrepancy is with the weights being recalibrated vs the test standard they're being calibrated to. None of which is shocking to anyone involved, just puzzling.

Re: New theory claims to unite Einstein's gravity with quantum mechanics

#135
post #19

Earlier quoted context omitted.

Untestable theories are not theories - I mean, for what purpose and why care?

Yeah they are, they just cannot be verified - or cannot be verified yet. The higgs boson theory was theorised in 1964 and it was untestable at the time, but that theory got the funding together to create one of the largest and most expensive scientific instruments built to prove the theory. Nuclear fusion was theorised in 1915, again untestable at the time, and look how far we've come. The above comment is an anti-sc…

Usually when people say something is untestable they don't mean like the Higgs Boson. It was testable, they just needed the proper tools. This was always known and was being actively worked towards. An untestable theory is one that cannot be tested regardless of the tools due to the nature of the theory. Multiverse is an example of an untestable theory. There is no way we know of to actually prove or disprove it. And its fair to question their legitimacy as theories. As testing a hypothesis is the core action of the scientific method, it logically follows that anything untestable is fundamentally not science and therefore not a theory.

Re: New theory claims to unite Einstein's gravity with quantum mechanics

#137
post #102

Earlier quoted context omitted.

Not new, Efficient Markets Hypothesis is like this. "I haven't heard of a way to make money from trading so there isn't one" is my caricature of it.

Isn't it more like: "exploitation of a market inefficiency renders the market efficient over time", or something to that effect? Or rather, (others) making money from trading is what makes it hard (for you) to make money from trading.

Sure, depends on how you encounter it. Most often on forums someone will show up wanting to hear about how to write a strategy, and they are rebuffed with "nobody would ever publish that".

Re: New theory claims to unite Einstein's gravity with quantum mechanics

#138
post #33

The article mentions the 5000:1 odds bet, but reading the text of the bet itself is hilarious: >>> Whereas Carlo Rovelli and Geoff Penington firmly believe that gravity is better described by a quantum theory. >>> And whereas Jonathan Oppenheim is more sympathetic to other possibilities (i.e. doesn’t have a clue) ... [1] - https://www.ucl.ac.uk/oppenheim/pub/quantum_vs_classical_bet...

Interesting that three so obviously intelligent people could get the odds of the bet wrong: it’s not a 1:5000 bet, it’s a 2:5000 bet a.k.a. a 1:2500 bet.

Re: New theory claims to unite Einstein's gravity with quantum mechanics

#139
post #5

Is there a decent explanation of what the conflict is about, that is understandable with a non-physics-major college level maths background?

The curvature of space time depends on the distribution of mass and energy within that space time. If you're modeling general relativity classically with quantized mass and energy at very small scales, stuff gets "weird". If a particle isn't in a well-defined location with a well-defined energy, then what is its effect on the curvature of space time around it?

Re: New theory claims to unite Einstein's gravity with quantum mechanics

#140

Earlier quoted context omitted.

Can you give any examples of times you’ve easily anticipated X when a whole field of subject matter experts have demonstrably overlooked it?

This isn't to agree with the parent comment, but wouldn't this situation itself be an answer to your question (assuming the claim is true)? Laymen like me easily anticipated mass divergence, but purportedly scientists have been surprised by it.

This comment chain is getting circular. We can't use this as an example for itself by assuming that it is true.
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