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Einstein's relativity rules chemical bonds in heavy elements, new research shows

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Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#181

Post by LorenPechtel »

sigmoid10 wrote: post #124
gcanyon wrote: post #123

> The increased nuclear mass causes orbiting electrons to speed up to a significant fraction of the speed of light, where the rules of Einstein’s theory of relativity are important. Fun fact: this is why mercury is liquid at room temperature. Its inner electrons move at close to 60% the speed of light, pulling in its outer electrons more tightly, making it harder for it to bond and be solid. (I am not a physicist, do…

I guess the more interesting question is why this doesn't happen for neighbouring elements in the periodic table?

You can start your car.

Without relativistic effects a lead acid battery would put out about .2V rather than 2V.

Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#182

Post by fc417fc802 »

HarHarVeryFunny wrote: post #136
DiscourseFan wrote: post #34

Earlier quoted context omitted.

But oftentimes theoretical chemistry is not as important as what we get out of experiments because unlike physics, which attempts to derive general laws of nature, chemistry has to deal with the nitty gritty of the diversity of actual miscroscopic interactions of things. Any theory that is not entirely rigorous or even has slight room for an exception will be ignored by necessity, and physics is chock full of such ex…

I think that as you ascend the scale of complexity, and just system size, then necessarily empiricalism and rote learning/memorization has to take over from more reductionalist explanations. Physics, whether at atomic level, or on a much larger scale, is simple enough that reductionism usually works and you can calculate behavior from first principles using a few memorized "laws" Biology is well past the point of com…

> unless perhaps you are at the level of aspects of cellular behavior that can be analyzed in terms of chemistry.

Only in the most hand-wavey sense. Actual simulation of the cell interior with even comically coarse grained models is prohibitively expensive. It comes up a lot in neuroscience where it sure would be nice to be able to credibly simulate even a single neuron at the molecular level. (I'm several years out of date on the state of that field so it's possible someone managed to pull it off in the meantime but even if so the broader point still stands.)

Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#183

Post by vatsachak »

zkmon wrote: post #79
vatsachak wrote: post #56

Earlier quoted context omitted.

P ^ not P => _|_ The axioms of a logic that are consistent will definitely not let a statement be true and false at the same time.

Those axioms do not have a basis other than observations at human scale.

They have a basis in the formal scale. The cool thing about formal logic is that it's all about physical changes.

Now, the meaning of the statements is definitely human, but the proofs go beyond

Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#184

Post by westurner »

westurner wrote: post #127

But what about superfluids (BEC Bose-Einstein Condensates)? Is it a different set of rules for superfluids like 3He, or should the laws of superfluids cover heavy elements, too? Here, again, a need for a model of superfluid quantum gravity

Today I ran into this problem again.

What is the difference between sound and radio?

A traditional explanation with Relativity says: Sound is compression waves through a medium, and radio is electromagnetic waves through no medium, and light is photon waves through no medium but gravity due to mass attraction changes the paths of the massless photon particles transiting through spacetime in a vacuum at c the max speed of light and photonic causation.

(But is there spooky action at a distance faster than c that's more than chance correlation?)

Superfluid Quantum Gravity (SQG) and Superfluid Vacuum Theory (SVT) say that the vacuum of space is not nothing; at Bose-Einstein Condensate (BEC) phases of matter, there is a new description of the particles in space. And there should be, because really what is between atoms and electrons in the nothingness of the vacuum of space at what altitude and temperature?

And so to describe the path of massive photons and standard massless photons through the superfluid of space, additional or alternate or sufficient superset mechanics to describe dilatant fluid model of spacetime at macro and micro and particle scales.

Is it Proca fields for massive photons with Airy-beam-like curvature?

/?hnlog Ctrl-F dilatant; dilatant quantum fluid model of gravity :

- > How to test whether MHD or SQR [or SQG or SVT] best explain the given phenomena?

- "Persistent shock wave around dead star puzzles astronomers" https://news.ycombinator.com/item?id=46679704

- "A universal speed limit for spreading of coherence" https://news.ycombinator.com/item?id=45928486 :

> "Physical vacuum as a dilatant fluid yields exact solutions to Pioneer anomaly and Mercury’s perihelion precession" (2019) https://cdnsciencepub.com/doi/10.1139/cjp-2018-0744 .. https://news.ycombinator.com/item?id=45220585

Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#185

Post by fc417fc802 »

smj-edison wrote: post #70
scheme271 wrote: post #30

Earlier quoted context omitted.

At upper undergrad and grad levels, it probably would have improved a lot. The issue is that a lot of the why requires quantum mechanics to really explain and even that becomes intractable extremely quickly. Like you can probably do the analytic solutions for hydrogen atoms and electrons but once you get to helium or past that, you basically need to use a computer to do numeric calculations and even there, you are ve…

And also emergent behavior means that at each level, we need different abstractions to deal with the problem. Even with chemistry, there's ideas like benzene rings that are aromatic, that you couldn't predict that from particle-particle interactions. So it's not just that it's hard to understand quantum mechanics, it's that understanding QM doesn't mean you'll understand the problems that chemistry deals with.

I don't think that's quite right. We only have to worry about emergent behavior precisely because running a full simulation is intractable. If we could "just" run full QM instead of MD with all those lossy force field approximations all the emergent behavior would happen on its own. But obviously doing that is well past science fiction and into the territory of wild fantasy.

I think misconceptions commonly arise because there are so many examples where we know how to simulate each part with arbitrary precision but the scale of the system is where it all falls over. That just doesn't match up with our everyday experiences because systems on the scale of avagadros number or O(n^7) algorithms applied to absurdly small timesteps are anything but typical. It's difficult for people to wrap their minds around the implications of having to consider things on nanosecond timescales.

Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#186

Post by zyklu5 »

LorenPechtel wrote: post #181
sigmoid10 wrote: post #124

Earlier quoted context omitted.

I guess the more interesting question is why this doesn't happen for neighbouring elements in the periodic table?

You can start your car. Without relativistic effects a lead acid battery would put out about .2V rather than 2V.

Nice! Thanks for this.

More details at: https://arxiv.org/abs/1008.4872

Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#187

Post by vasco »

DiscourseFan wrote: post #78
vasco wrote: post #74

Earlier quoted context omitted.

> and still nobody has gone beyond Aristotle and Kant in giving anything close to a rigorous definition of life as such You stopped reading after the 1800's? Schrödinger told us life is what feeds on negative entropy and that is pretty good.

I guess that is true, but it isn't much. But my basic point was that before you can have "life" you have to have a theory of life which ultimately requires metaphysics, and there hasn't been much of an update to our understanding of what would ground a definition of life beyond Aristotle and Kant, and even their work is not determinative by any means.

Just because you picked 2 guys it doesn't mean nobody else had any different ideas. What a weird position to have, unless you literally read everything. There's so many theories. You didn't even include religions

Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#188

Post by westurner »

westurner wrote: post #184
westurner wrote: post #127

But what about superfluids (BEC Bose-Einstein Condensates)? Is it a different set of rules for superfluids like 3He, or should the laws of superfluids cover heavy elements, too? Here, again, a need for a model of superfluid quantum gravity

Today I ran into this problem again. What is the difference between sound and radio? A traditional explanation with Relativity says: Sound is compression waves through a medium, and radio is electromagnetic waves through no medium , and light is photon waves through no medium but gravity due to mass attraction changes the paths of the massless photon particles transiting through spacetime in a vacuum at c the max spe…

Is the dilatant quantum superfluid of spacetime itself also fracturable?

Like Oobleck? (2 parts cornstarch to 1 part water)

Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#189

Post by prox »

mr_toad wrote: post #172
prox wrote: post #160

Earlier quoted context omitted.

I think I recently learned that the Higgs is actually not that much part of imparting mass for atomic particles. I thought it imparted all mass.

> I thought it imparted all mass. It’s all relative; in the quarks frame of reference it does get all its mass from the interaction with the Higgs field.

I really want to read more about this. It’s fascinating but also very difficult to wrap your head around. I did enjoy the Feynman talks.

Re: Einstein's relativity rules chemical bonds in heavy elements, new research shows

#190

Post by smj-edison »

fc417fc802 wrote: post #185
smj-edison wrote: post #70

Earlier quoted context omitted.

And also emergent behavior means that at each level, we need different abstractions to deal with the problem. Even with chemistry, there's ideas like benzene rings that are aromatic, that you couldn't predict that from particle-particle interactions. So it's not just that it's hard to understand quantum mechanics, it's that understanding QM doesn't mean you'll understand the problems that chemistry deals with.

I don't think that's quite right. We only have to worry about emergent behavior precisely because running a full simulation is intractable. If we could "just" run full QM instead of MD with all those lossy force field approximations all the emergent behavior would happen on its own. But obviously doing that is well past science fiction and into the territory of wild fantasy. I think misconceptions commonly arise beca…

Yes and no. If we could "just" run full QM, there's still the issue of building abstractions regarding the emergent behavior. A full system is still useless if you can't describe things like ligands, carbon rings, etc. So regardless of whether we can simulate it, we still need terms for higher level concepts.

But yes, nano and even femtosecond level second stuff is pretty mind bending.

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