4 ms·
Just ignore the "virtual particles" part. Most of the mass comes from the binding energy. As in the rest masses of the individual quarks is small compared to to
by sharpneli 4y ago
Just ignore the "virtual particles" part. Most of the mass comes from the binding energy. As in the rest masses of the individual quarks is small compared to total mass of proton.
Virtual particles themselves can always be ignored as they are not physical. They're purely a computational method in some approaches. They don't exist in others at all. And even when they are part of the method what kind they are depends. Looking at momentum space? Your virtual particles can have any position. Looking at position? Your virtual particles can have any momentum.
Alternatively: Virtual particle just means that if you have a certain kind of field, what kind of "particles" you need to sum up to get that kind of field. The field itself is the physical thing. Viewing it mathematically as sum of virtual particles is just a mathematical viewpoint.
- xeromal 4y agoIs the binding energy made up of gluons?
- simonh 4y agoLooks like it, quarks are bound together by gluons so as you go up the energy scale and 'see' more quarks the gluon energies dominate. In fact about 99% of the Proton's mass is in the form of this binding energy.
- ars 4y agoBinding energy is not gluons. Gluons are massless, binding energy is just energy, it's not a particle.
- baq 4y agoNo such thing as ‘just energy’, every force needs a force carrier particle and gluons are that for the strong force. Photons are massless, too.
- sharpneli 4y agoSaying it's made of gluons is exactly the same as saying that a charged object in electric field has it's potential energy made of photons. It's not exactly informative nor true. Yes you can describe the electric field as sum of virtual photons but that's different to a normal photon. And even then the electric field is not the same as the potential energy. Sure it defines it but it's not the same as the potential energy of the charged object. In case of protons it's the same. It's better to think of it as a field, which it is. Gluon in itself is "just" an excitation of that field. Just like photon is an excitation of the electric field. And the binding energy of the proton comes from the quarks interacting with the gluon field. The reason I'm talking so much against the virtual particle viewpoint because then people will start thinking of some things whizzing about. That's not what happens. It's a field. It's actually better to think of even the normal fermions with mass with fields, because that's what they are. It's no longer surprising that how does electron go through both slits at the same time or how all electrons are identical. Of course they are identical as there is just one electron field that has a very specific kind of excitation that propagates. This is not some random "Look at my weird theory". It's what Quantum Field Theories are. I mostly blame bad science journalism looking at Feynman diagrams (a great mathematical tool, don't get me wrong) that has people thinking too much about virtual particles.
- simonh 4y agoI didn't say the binding energy is gluons, but I suppose it's more accurate to say that the binding energy of the strong nuclear force is mediated by gluons.
- ars 4y agoIt's not made of anything, it's just energy. To think of a proton as containing tons of gluons would be a mistake. Additionally gluons are expected to be massless, they basically come into existence as needed.
- sharpneli 4y agoIt's not. Just like how if you push two identically charged plates towards eachother the potential energy in that system is not made of photons. Sure you can describe the electric field in that case by a viewpoint where you sum virtual photons together to get said electric field. Whereas a non virtual photon is alltogether a different thing. You can actually describe a normal non virtual photon as a sum of virtual photons. Point is that virtual particles are just a mathematical tool. Actual real gluons do exist and they're analogous to the actual photon. In case of electromagnetism the actual stuff is the electric field. With proton (so in quantum chromodynamics) it's the gluon field. It's called that because every particle has a field and every field a particle. It would be kinda like calling electric field a photon field. Same difference.
- FranchuFranchu 4y agoIt's a bit like the "energy" in an electric capacitor. It's a property of the system's state that is related to the interactions between the particles. In a charged capacitor, there's a lot of electrons on one side, but very few of them on the other. When you close the capacitor, suddenly you get a lot of energy out of it.