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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

#191

Post by Joska929 »

westurner wrote: post #188
westurner wrote: post #184

Earlier quoted context omitted.

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)

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

#192

Post by turtlesdown11 »

nanolith wrote: post #14

Wait... wasn't it already understood that relativity influences electron orbits of heavy elements? I clearly remember being taught some of this in physics, in the mid-noughties. For instance, we know that gold gets its color from relativistic effects. https://physics.aps.org/articles/v10/s3

subheader explains the article in case you were wondering

> Researchers have shown the first direct experimental evidence that the textbook triple bond structure breaks down in heavy elements, where relativity makes the rules.

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

#193

Post by lr1970 »

zyklu5 wrote: post #186
LorenPechtel wrote: post #181

Earlier quoted context omitted.

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

Thanks for the link to the paper published in 2010 (16 years) ago. The OP article from Brown reads as if they were the first to establish importance of Special Relativity for heavy atoms which is not true.

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

#194

Post by LoveMortuus »

lr1970 wrote: post #193
zyklu5 wrote: post #186

Earlier quoted context omitted.

Nice! Thanks for this. More details at: https://arxiv.org/abs/1008.4872

Thanks for the link to the paper published in 2010 (16 years) ago. The OP article from Brown reads as if they were the first to establish importance of Special Relativity for heavy atoms which is not true.

I feel like that's often the case, right? Even gravity being describe first by Brahmagupta and Bhaskara II before Issac.

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

#195

Post by sigmoid10 »

nyrikki wrote: post #167
gweinberg wrote: post #161

Earlier quoted context omitted.

OP claimed relativistic effects explain why mercury is liquid at room temperature. That may be part of the story, but it isn't the whole thing, since other heavy elements are not liquid at room temperature.

Explaining relativistic effects in plain text forums to a general audience is a big ask, but here is a link to the first study[0] that gave evidence but it has long expected. [0] https://onlinelibrary.wiley.com/doi/epdf/10.1002/anie.201302...

That still doesn't answer why these relativistic effects don't cause neighbouring elements to be liquid. Electron velocities should be quite similar for them. There must be something apart from relativistic effects that makes mercury special in that regard.

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

#196

Post by asdff »

whattheheckheck wrote: post #41
asdff wrote: post #22

Earlier quoted context omitted.

Not in undergraduate chemistry at least. Maybe chem majors had it different. Organic chemistry 1 was basically rote memorization of various reactions and catalysts and their required conditions. Exam questions would be some organic molecule start and some organic molecule end result and you'd have to draw out each and every intermediary step to get to that end result. Organic chemistry 2 was exactly the same just mor…

And people clutch their pearls at ai not really understanding anything when people describe university experiences and lessons like this...

You understand it well enough for the real world use cases where you can say simply look up what conditions a particular rarely used catalyst might run at. No issues confusing it with another catalyst in your head in the real world.

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

#197

Post by alok-g »

colechristensen wrote: post #164
alok-g wrote: post #155

Earlier quoted context omitted.

Thanks for the insights. I am interested in learning all this stuff. Am currently going through just Schrodinger's Equation. Do you have book recommendation(s) that include insights everywhere just like what you shared? Thanks.

These are books to train physicists, accessable-ish to a math heavy engineering undergraduate degree holder. The insights above are my own and extractable from this material but not necessarily stated out loud (unless I'm unconsciously plagiarizing which is entirely possible) * David Griffiths - Introduction to Elementary Particles * Chris Quigg - Gauge Theories of the Strong, Weak, and Electromagnetic Interactions A…

Thanks a lot. Have been watching these videos all day long! Looked through the first book too.

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

#198

Post by gus_massa »

alok-g wrote: post #156
gus_massa wrote: post #112

Earlier quoted context omitted.

You are mostly correct. The idea is that it has not a clearly definite position, but it has a distribution of probability to find it that looks like a "cloud" https://en.wikipedia.org/wiki/Atomic_orbital In a more abstract sense, has not a clearly definite speed, but it has a distribution of probability to find it in a speed graphic. The distribution of position and speed are defined by an equation and you must add a…

(Newbie here). And then going further, shouldn't there also be acceleration and its distribution? It says classical models could not explain why accelerating electrons were not radiating. If acceleration also shows up in QM, then ... a distribution of radiation?

[Sorry for the delay. I really had to watch that soccer game and kids don't have school on Sunday.]

There is an acceleration distribution, but the acceleration operator is strange. I don't remember the details and a quick google search confirms that it's strange.

It's complicated... let's oversimplify some details...

In QM the electron must jump from one orbital to another, and the difference in energy is emitted as radiation as a photon. If the electron jumps from A to B, then B must be empty. So if A is the orbital with less energy then it can't emit. Also if B is full, it can't emit.

For a big enough system, there are plenty of options for B and you get a very good approximation that is the classic rule that says that accelerating electrons emit photons.

There are weird cases, like in a neutron star, there are too many electrons trapped by gravity so all possible B are full, and you have electrons that can't emit.

It you want a tabletop experiment, the keyword is "fermion gas" that are gas of fermions (like electrons) that are very cold and very dense and they have a strange repulsion that is not explained classically. It is caused because there are jumps that are forbidden because the destination is full. (If you heat them or give them more room to be diluted, this strange repulsion almost disappears and you can aproximarte them as a classical gas.)

> a distribution of radiation?

If you measure the radiation far away, you have a distribution of possible colors/energy of the photon, because the electron may choose to jump form A to B1, B2, B3, ... This is like the lines color of gas lamps.

If you measure close enough, you have to draw Feynman diagrams and the photons may have a slightly different value of color/energy. But it's complicated and I'm not sure of the details. I guess it's related to the acceleration distribution, but I'm not sure of the details again.

---

The easy answer is that "acceleration -> radiation" is only a useful approximation when the system is big enough to ignore the quantum effect.

The hard answer is probably that you have to study like 10 years of physics to be sure and explain me the details. :)

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

#199

Post by alok-g »

gus_massa wrote: post #198
alok-g wrote: post #156

Earlier quoted context omitted.

(Newbie here). And then going further, shouldn't there also be acceleration and its distribution? It says classical models could not explain why accelerating electrons were not radiating. If acceleration also shows up in QM, then ... a distribution of radiation?

[Sorry for the delay. I really had to watch that soccer game and kids don't have school on Sunday.] There is an acceleration distribution, but the acceleration operator is strange. I don't remember the details and a quick google search confirms that it's strange. It's complicated... let's oversimplify some details... In QM the electron must jump from one orbital to another, and the difference in energy is emitted as…

Thanks a lot for sharing. This is insightful for me ... I now know better on how to think and what to look for as I dwell deeper.

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

#200

Post by IAmBroom »

Jblx2 wrote: post #173
amelius wrote: post #144

Earlier quoted context omitted.

Meanwhile there are quarks inside every regular atom moving at speeds like 0.99995c ...

If the spatial extent of the proton is not infinite, this would imply that the charged quarks making up the proton are accelerating. Why aren't these quarks then emitting electromagnetic radiation, thus slowing down? I thought electrons were essentially standing waves around the nucleus, and thus not accelerating. Maybe there is a good youtube video explainer? Seems like there would also be an associated temperature…

"The laws that bind an ox do not bind Jupiter" applies to quantum particles.
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