J4ANification (November 30, 1999 at 12:00 am)

What is a quark again?

AnLa061095 (November 30, 1999 at 12:00 am)

So if a Nutron decays into a Proton an electron and an antinutrino. Then does a down quark have mass = 1 up quark, 1 electron and 1 antinutrino? N = P + e + n u + 2d = 2u + d + e + n 2d - d = 2u - u + e + n d = u + e + n

Pooua (November 30, 1999 at 12:00 am)

@Ender1337otron Yeah, well, we were talking about a sub-atomic particle (the neutron) to begin with (that is what this video clip is discussing), so, when I began talking about particles, that is the context you should have considered; sub-atomic particles. It just happens that quantum effects are not limited to sub-atomic particles.

Pooua (November 30, 1999 at 12:00 am)

@Ender1337otron Atoms *do* disappear and reappear at random, even across a barrier for which they do not have the energy to cross. This is known as atomic quantum tunneling, which has been observed for hydrogen in niobium.

Ender1337otron (November 30, 1999 at 12:00 am)

Also, I was mostly talking about the fact that it's an electron that you can't precisely know both the speed and direction at the same time. I took issue with you using the rather broad term particle. You can most certainly know the speed and direction of an atom or a baseball or almost anything besides an electron. Other than that I didn't have any problem with your thought. That's why I said "If by particle you mean electron then yeah."

Ender1337otron (November 30, 1999 at 12:00 am)

@Pooua Nope, that's why they refer to the atom as a "stable" arrangement. The electron disappears and reappears at random close to the nucleus. Atoms themselves don't do that.

Pooua (November 30, 1999 at 12:00 am)

@Ender1337otron My understanding is that even macroscopic objects have a probability of appearing anywhere in the universe at any given moment, though the probability for major displacement of a macroscopic object is virtually zero. The odds of even an electron suddenly appearing on the other side of the universe aren't very high, but it would be permitted under quantum mechanics. I'm not sure, but this might be analogous to the wave nature of objects (even baseballs have a wavelength).

Ender1337otron (November 30, 1999 at 12:00 am)

@Pooua If by particle you mean electron then yeah. Particle is a relative term that can mean many things, a bit of dust can be called a particle for instance.

MetalSpiral (November 30, 1999 at 12:00 am)

Neutron: Mammoth of the quantum world. B-)

vincentpistelli (November 30, 1999 at 12:00 am)

@AurumenK up and down quarks are not called that because of their motion. There are also charm, strange, top, and bottom quarks which obviously aren't named after movements.