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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

#91
post #86
post #40

What awful AI-generated illustrations. Anyway, is there any justification for treating spacetime as a smooth manifold, except for mathematical tractability?

I'm more annoyed with the captions. > … Carbon-60, one of the largest known molecules.

Eh, C₆₀, one of the largest molecules with observed quantum interference, close enough.

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

#92
post #75

Earlier quoted context omitted.

I think the real question is: where is the evidence that scientists find it mysterious? That doesn't need any sort of explanation, just a reference for a claim made by a commenter. As with the other commenter, I've heard about the mass divergence before, but never that anyone found it surprising.

As has even been discussed on HN over the years (!), the cause is unknown.* This is one of the motivations to replace the official kilogram with a definition based on measurable natural quantities, as had been done with the second and the meter. It took until 2018 to do so: https://www.nist.gov/si-redefinition/kilogram-introduction * it’s not like there aren’t good theories but you can’t experiment directly on “the”…

I'm neither seeing the cause being mentioned as unknown in that link, nor would the cause being unknown imply anything being mysterious?

Like if you find that your car has broken down after 200k miles, you might not be able to determine the cause, but it wouldn't exactly be some kind of mysterious physical phenomenon that would puzzle scientists. Obviously, something wore out. Why/how is this any different?

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

#93
post #6
post #4

Earlier quoted context omitted.

What made them mysterious? Aren't there always some fraction of atoms or molecules with sufficiently high energy to escape the object?

The fact that you, a random internet guy, knows this makes me believe that the world's top experts on measuring this exact thing probably thought of it, and if there is a mysterious divergence this probably doesn't account for it.

Did you ever pause to think "is this comment worth posting"? Maybe you should.

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

#94
post #4

Earlier quoted context omitted.

What made them mysterious? Aren't there always some fraction of atoms or molecules with sufficiently high energy to escape the object?

If it were simply a matter of losing particles, I'd expect that one of the many very capable metrology labs around the world would've devised an appropriate experiment, e.g. storing two exact same masses at slightly different temperatures near absolute zero and characterizing the difference in mass (since presumably the higher temperature sample would lose slightly more mass if it were down to high energy particles).…

Make sure to store them very deep underground down a mineshaft, so random cosmic rays don't ever knock a few atoms loose.

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

#96
post #85
post #47

Earlier quoted context omitted.

Perhaps they're post-edited somewhat but there isn't a way you're convincing me those are fully handmade. Look at the nonsensically warped tiles. Look at the rods suspending some of the globes but not others in a random fashion, look at the illegible "writing".

I think you're right. I don't really have a problem with AI generated art being used in articles like this. After all, what kind of alternative visual can you put alongside an article about fundamental theories of nature? If AI art helps to reduce the cost of scientific journalism (without decreasing the quality) then I'm ok with it. Having said that, to produce art that actually works is clearly not easy. If you've…

Oof yeah, I just saw the article pics. I don't have an issue with AI assistance, but the final output here was just kind of incoherent and confusing. Like an unrelated stock photo. I understand that it is hard to control but that just means that the artist needed to do a better job to make something more coherent, more informative and less generic.

Unless yeah as you said, it's just too abstract to put anything coherent, in which case I guess it works (though the mass weighing image surely could have been better than some generic sci fi thing)?

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

#97
post #20

Earlier quoted context omitted.

I find that it saves time to just start by assuming the experts haven't thought of X because of how many times I've seen assuming that they _have_ thought of X turn out to be a poor assumption, across many domains.

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.

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

#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 12 significant digits -- a Canvendish-type measurement could give you maybe 5 or so, I think.

Or is it because the Penning trap measures "inertial mass" but they really want a measurement of "gravitational mass"? But wouldn't inertial mass fluctuate the same way?

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

#100

Earlier quoted context omitted.

Sure, radioactivity. But, Le grand K is made of naturally occurring platinum of which most of the isotopes are observationally stable[0] and the one isotope that isn't has a half-life of 6.5×10^11 and only makes up 0.012% [1]. So yeah I don't buy the unstable explanation to even begin to show the divergence, let alone "weight gain". [0] https://en.wikipedia.org/wiki/Stable_nuclide#Still-unobserve... [1] https://en.wi…

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

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