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Does this have real consequences for material science or chemistry? It's difficult to gauge the actual impact from the hyperbole in the article (similar to dis

by fooker 3y ago

Does this have real consequences for material science or chemistry? It's difficult to gauge the actual impact from the hyperbole in the article (similar to discovery of black holes, etc).

downWidOutaFite 3y ago
This is experimental confirmation of existing accepted theories "The confirmation of the existence of the π-hole, as well as the σ-hole before it, fully demonstrates the quality of the theoretical predictions of quantum chemistry, which have accounted for both phenomena for decades."
gus_massa 3y ago
IIUC: For Material Science: very little For Chemistry: Reading the paper, it looks like DFT[1] gets the same result than the experiments. It's nice to confirm DFT in a weird scenario, but it's not groundbreaking. There are a few versions and parameters to tweak in DFT, so it may help to choose the right one for similar molecules, but I'm not an expert in DFT. Black holes: That was totally hyperbole. I chuckle. It looks like people have been using pi-holes to predict the strength of the bound between molecules [2]. It's nice to be able to "see" them in a real example, but doesn't look groundbreaking. (There is always a small possibility that this technique is improved and in a few years everyone is using it to identify molecules or something like that. I don't expect that, but you never know. Sometimes experimental results create a complete new branch.) [1] https://en.wikipedia.org/wiki/Density_functional_theory https://en.wikipedia.org/wiki/Density_functional_theory [2] I made a search in google, and I cherry-picked these articles https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8003638/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8003638/ https://pubs.rsc.org/en/content/articlelanding/2021/cp/d1cp02602j https://pubs.rsc.org/en/content/articlelanding/2021/cp/d1cp0...
- maverwa 3y ago
  Would it no be comparable to "seeing" the first black hole long after predicting them? AFAIK we knew black holes exists long before we finally were able to observe them. (And we still dont see them, just their effects). Is it the same way here? We knew it exists, we can use that knowledge to describe things better, but we were unable to snap a picture, until now? Still not sure if thats what the article meant, just curious.
  - fooker 3y ago
    Well, in both these cases we haven't seen the thing. We just have more creative and accurate visualization of sensor data, somewhat far from what we could see or photograph in the visible spectrum.
  - gus_massa 3y ago
    I work in Quantum Chemistry (aka Math Applied to Molecular Physics) so I see somewhat similar stuff every other day. The problem is that if the predictions by computer were wrong, it would have been too easy to spot differences in many other cases, like the energy of some molecules, or the angles of the atoms of other molecules, or the reactions or other molecules. The exact calculations are horrible slow, but there are good enough approximations like DFT and some other methods that are more accurate but too slow to be applied to big molecules (like O(N^12) where N is the number of atoms, or if you are not a purist N is 5 times the number of atoms, or something like that because the details are more complicated). Anyway, the result is an infinite sum of slater determinants, but usually a few are enough. There is very little room for surprises. I'm not an astronomer, so I have less idea about possible problems with black holes. It seams that the neutron stars have a lot of internal structure near the surface, https://en.wikipedia.org/wiki/Nuclear_pasta https://en.wikipedia.org/wiki/Nuclear_pasta because in the surface you have a mix of neutrons and protons. In the center, it may possible have a mix of normal mater and matter made also with the strange quark https://en.wikipedia.org/wiki/Strange_matter https://en.wikipedia.org/wiki/Strange_matter So there are a lot of weird things we don't understand completely and may case neutron star to avoid being crushed into a black hole. Also, at very high gravity forces, we must consider quantum gravity, that is a theory we had no t discovered yet. We discovered many black holes so all these problems I imagine are not so problematic. But anyway, there is a lot of internal structure that could have been a problem until they got a confirmation.

by fooker 3y ago

Does this have real consequences for material science or chemistry? It's difficult to gauge the actual impact from the hyperbole in the article (similar to discovery of black holes, etc).

downWidOutaFite 3y ago

This is experimental confirmation of existing accepted theories "The confirmation of the existence of the π-hole, as well as the σ-hole before it, fully demonstrates the quality of the theoretical predictions of quantum chemistry, which have accounted for both phenomena for decades."

gus_massa 3y ago

IIUC: For Material Science: very little For Chemistry: Reading the paper, it looks like DFT[1] gets the same result than the experiments. It's nice to confirm DFT in a weird scenario, but it's not groundbreaking. There are a few versions and parameters to tweak in DFT, so it may help to choose the right one for similar molecules, but I'm not an expert in DFT. Black holes: That was totally hyperbole. I chuckle. It looks like people have been using pi-holes to predict the strength of the bound between molecules [2]. It's nice to be able to "see" them in a real example, but doesn't look groundbreaking. (There is always a small possibility that this technique is improved and in a few years everyone is using it to identify molecules or something like that. I don't expect that, but you never know. Sometimes experimental results create a complete new branch.) [1] https://en.wikipedia.org/wiki/Density_functional_theory https://en.wikipedia.org/wiki/Density_functional_theory [2] I made a search in google, and I cherry-picked these articles https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8003638/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8003638/ https://pubs.rsc.org/en/content/articlelanding/2021/cp/d1cp02602j https://pubs.rsc.org/en/content/articlelanding/2021/cp/d1cp0...

maverwa 3y ago
Would it no be comparable to "seeing" the first black hole long after predicting them? AFAIK we knew black holes exists long before we finally were able to observe them. (And we still dont see them, just their effects). Is it the same way here? We knew it exists, we can use that knowledge to describe things better, but we were unable to snap a picture, until now? Still not sure if thats what the article meant, just curious.
- fooker 3y ago
  Well, in both these cases we haven't seen the thing. We just have more creative and accurate visualization of sensor data, somewhat far from what we could see or photograph in the visible spectrum.
- gus_massa 3y ago
  I work in Quantum Chemistry (aka Math Applied to Molecular Physics) so I see somewhat similar stuff every other day. The problem is that if the predictions by computer were wrong, it would have been too easy to spot differences in many other cases, like the energy of some molecules, or the angles of the atoms of other molecules, or the reactions or other molecules. The exact calculations are horrible slow, but there are good enough approximations like DFT and some other methods that are more accurate but too slow to be applied to big molecules (like O(N^12) where N is the number of atoms, or if you are not a purist N is 5 times the number of atoms, or something like that because the details are more complicated). Anyway, the result is an infinite sum of slater determinants, but usually a few are enough. There is very little room for surprises. I'm not an astronomer, so I have less idea about possible problems with black holes. It seams that the neutron stars have a lot of internal structure near the surface, https://en.wikipedia.org/wiki/Nuclear_pasta https://en.wikipedia.org/wiki/Nuclear_pasta because in the surface you have a mix of neutrons and protons. In the center, it may possible have a mix of normal mater and matter made also with the strange quark https://en.wikipedia.org/wiki/Strange_matter https://en.wikipedia.org/wiki/Strange_matter So there are a lot of weird things we don't understand completely and may case neutron star to avoid being crushed into a black hole. Also, at very high gravity forces, we must consider quantum gravity, that is a theory we had no t discovered yet. We discovered many black holes so all these problems I imagine are not so problematic. But anyway, there is a lot of internal structure that could have been a problem until they got a confirmation.