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As a person with at least basic knowledge of physics and computer simulations I find it odd that even basic atoms are so difficult to simulate. Maybe this just

As a person with at least basic knowledge of physics and computer simulations I find it odd that even basic atoms are so difficult to simulate. Maybe this just shows my ignorace on the topic :)

gus_massa 8y ago
If you want to simulate an Hydrogen atom (assuming that the proton is a single particle), it's not so difficult. There is a proton, an electron, and they have electromagnetic charge that is quite weak, so you only have to consider a few photons that travel between the proton and the electron. Also, the photon don't have charge, so one photon don't interact with other photons. (There are some small corrections here and there ...) To simulate the inner part of a proton or a neutron, you have to consider the tree quarks. The quarks have color, that is unrelated to the usual color, it's just the name of the "charge" of the strong force. Instead of photons, they interact with gluons. But gluons have color, they are "charged", so you now must consider not only the quark-quark interactions, but also the gluon-quark interactions, and the gluon-gluon interactions. All these interactions use more gluons. And the strong force is strong, so there is a lot of energy floating around, that can create pair of virtual quarks and antiquarks. And now you have to add the interaction of the virtual quarks, that creates a soup of more gluons and more virtual quarks. And the strong force is strong, so all this soup of interaction has big affect, it's not a small correction to the easy model. Some data: * IIRC In a fast moving proton/neutron, half of the energy and momentum is carried by the quarks (real or virtual) and half by the gluons * IIRC the three original quarks only are 10% of the mass of the proton/neutron. I couldn't find a good link, but at least you can start with https://en.wikipedia.org/wiki/Strong_interaction https://en.wikipedia.org/wiki/Strong_interaction

As a person with at least basic knowledge of physics and computer simulations I find it odd that even basic atoms are so difficult to simulate. Maybe this just shows my ignorace on the topic :)

gus_massa 8y ago

If you want to simulate an Hydrogen atom (assuming that the proton is a single particle), it's not so difficult. There is a proton, an electron, and they have electromagnetic charge that is quite weak, so you only have to consider a few photons that travel between the proton and the electron. Also, the photon don't have charge, so one photon don't interact with other photons. (There are some small corrections here and there ...) To simulate the inner part of a proton or a neutron, you have to consider the tree quarks. The quarks have color, that is unrelated to the usual color, it's just the name of the "charge" of the strong force. Instead of photons, they interact with gluons. But gluons have color, they are "charged", so you now must consider not only the quark-quark interactions, but also the gluon-quark interactions, and the gluon-gluon interactions. All these interactions use more gluons. And the strong force is strong, so there is a lot of energy floating around, that can create pair of virtual quarks and antiquarks. And now you have to add the interaction of the virtual quarks, that creates a soup of more gluons and more virtual quarks. And the strong force is strong, so all this soup of interaction has big affect, it's not a small correction to the easy model. Some data: * IIRC In a fast moving proton/neutron, half of the energy and momentum is carried by the quarks (real or virtual) and half by the gluons * IIRC the three original quarks only are 10% of the mass of the proton/neutron. I couldn't find a good link, but at least you can start with https://en.wikipedia.org/wiki/Strong_interaction https://en.wikipedia.org/wiki/Strong_interaction