Every time you see a macroscopic phenomena, you are looking at a stupidly high amount of quantum levels with very similar energies.

Either way, quarks don't have an electron-like magnetic moment, so they aren't capable of coupling to the EM field.

> Exclusion Statement: Molecular orbital theory is recommended as a way to provide deeper insight into bonding. However, the AP Exam will neither explicitly assess molecular orbital diagrams, filling of molecular orbitals, nor the distinction between bonding, nonbonding, and antibonding orbitals.

Orbital theory is usually taught in organic chemistry and then inorganic for those who take that in college. AP chem targets "gen chem" which does not, as the above statement says, does not get into orbitals on that level at all. I'm familiar with gen chem as taught at least in 3 universities, none touched molecular orbitals.

If someone were to teach orbital theory in general chemistry, it would be a lot of hand waving and not much actual mathematics which was the point of the original comment. To cover molecular orbital theory is satisfactorily. You need to know quite a bit of the mathematics behind differential equations and statistical mechanics etc. AP chem isn't going to cover this. But maybe your 9th grade differential geometry class covered all this ;))

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

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.

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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. :)

And here come the relativistic effects, which essentially scale with nuclear charge of the nucleus come to play and they are significantly stronger for Hg than Cd. If I remember correctly (although I read about it a long time ago so I may be a bit rusty) these strong relativistic effects cause something called "relativistic contraction of the 6s orbital" which results in the electrons on this orbital being more strongly bound than they would be, if there would be no relativistic effects (which can be theoretically compared by setting c -> infinity in the equations used to solve electronic structure theory). AFAIR Copernicium should also be liquid in room temperature for similar reasons, but since it is not very long lived and it is difficult to produce testing this will likely be very hard if not impossible to check (though if I remember correctly there was something called "relativistic maximum" which happens in the 6th and not 7th row of periodic table for some reason, so it should be higher than for mercury; though I can't remember the details why this is so).

Of course this is a bit simplified picture and there are surely more details regarding how exactly relativistic effects influence the energies and consequently how this influences the melting temperature of mercury (I suppose they are in the Calvo, Pahl, Wormit and Schwerdtfeger paper linked earlier in this thread), but I think the combination of the electron configuration and strong relativistic effects explain why other neighbors are not liquid.

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 complexity where you can do this most of the time, unless perhaps you are at the level of aspects of cellular behavior that can be analyzed in terms of chemistry.

Chemistry is in-between physics and biology in terms of complexity. In simple cases chemistry can be explained in terms of physics, but as AlphaFold has shown when you get to a certain level of complexity (in this case protein folding) empiricism takes over and you need to perform experiments and memorize results.

I think modern science and philosophy has a reasonable understanding of what life is, even if you disagree. This is certainly more a matter of philosophy than science, but it seems the best definition of life is based on the ability of a system to actively maintain a boundary between itself and the external world, thereby combating the 2nd "law" (statistical tendency) of thermodynamics. Maybe an interesting/useful definition (which is somewhat arbitrary) also needs to involve something like consuming energy/resources from the environment.

You stopped reading after the 1800's? Schrödinger told us life is what feeds on negative entropy and that is pretty good.

Edit: and less universal. Physics underlies biology, chemistry, nuclear tech & more. Biology (so far) only applies to carbon-based life as we know it on Earth.

This is just a data problem though. From the perspective of a deterministic universe, creative works theoretically can be explained as a physics outcome (ignoring the impact of potential quantum randomness).

DFT works in many cases, but in some cases it doesn't estimate the energy right, due to how it bypasses some correlation calculations. Bonds are extremely sensitive to energy calculations, so you need to get super close to the actual energy in order to get useful results.

Anyways, someone with more experience here could probably add more, but that's what I've picked up so far.

truly ab initio methods involve figuring out electronic properties from scratch like ionization energy or bandstructure. the real issue is that we dont have exact relations for the exchange and correlation terms. we can know the kinetic energy and charge screening, but we dont know how the electrons are interacting with each other. generally the xc term is treated as a function of electron density or its gradient (see: lda, gga, meta-gga) but there are so many different ways to approximate that. different models are good for different applications also, like transition metals vs organics. and then theres the issue of basis sets (most people use gaussian basis sets that have been tuned over many years but theres also plane waves and finite element methods) which can also change results. and even once u have a decent approximation of density you can try perturbative methods (GW family, delta scf i count also) to try and improve the approximation. i am rambling and typing this on my phone. essentially yes, but often calculations are a little inaccurate. but more accuracy has a higher computational cost, which makes it hard to run larger simulations. tradeoffs of engineering. hope this was coherent.

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.

And this is for a very cold isolated molecule like in this experiment. If you have many moving molecules surrounded by a lot of water molecules at a usual room temperature, it gets much much much worse.

Practical attempts use a lot of heuristics and approximations, which risks fidelity.

To simulate a water molecule you do so with a weakly coupled SU(1) gauge theory (light does not interact with itself at tree order) problem where the masses of all constituents are orders of magnitude above the relevant energy scales (you can think of it as the electrons and nuclei and particles coming in and out of existence are contained in a renormalization scheme).

We have "good simulation models" of both, but the former is extraordinarily complicated compared to the latter for the reasons stated above.

“A” is described as being derived from the collision frequency of molecules in that specific reaction but really it’s just an arbitrary magic number you look up in a book for the specific reaction that you’re working with. It’s often relatively temperature invariant across some range of temperatures but go outside that range and it becomes a function of temperature too.

Pulling up the wikipedia for “Collision theory” will show you that there has been some work to derive values of A rather than just find them all experimentally for every reaction. But it’s still very unsatisfying to the curious mind.

“k” is the thermal conductivity of a particular material. Curious minds might wonder what’s hidden behind this constant. How would someone predict “k” for a novel theoretical material? Like, say, tetrahedrane?

It’s been awhile, otherwise I’d walk you through a graph containing a couple hierarchical nodes where one constant leads to another equation. But it’s a bit too late to pour through Perry’s Handbook right now to jog my memory.

I assume you are familiar with:

https://matt.might.net/articles/phd-school-in-pictures/

I hope and pray that your research helps to make the world a better place and that the rest of us can use your knowledge to help to make the world a place which merits your research.