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I was reading about Quantum physics and this really puzzled me. How can an electron move the speed of light? Of course, I’m assuming an electron has mass whereas a photon does not, and I understand that the issues is more about all possible trajectories of an electron needing to be averaged to determine it’s possible position and velocity. But still, wouldn’t some trajectories be nullified due to the inability of anything with mass to travel the speed of light? Or maybe I’m just a moron and my question is flawed!

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I think you misundestand. There is no way to determine the position, speed and direction of an electron, so they use probability to calculate, assuming that the electron can be anywhere in a given orbital “cloud”. That doesn’t mean the electron is everywhere at once, it means it has equal probability at being in any one location as it has in another location.

Do electrons travel at the speed of light ?

Electrons can not travel at the speed of light. Nothing with a mass can, and electrons do have a mass, Albeit a very small mass.

As I understand it, electrons don’t travel any continuous trajectory the way large objects do. They basically teleport from one place to another. When they say it travels every possible trajectory, they mean there’s a nonzero probability of finding it in any given place, with the probability decreasing the farther away you look. However, I think that’s still constrained by the speed of light–you won’t find it a zillion miles away an instant from now. For those trajectories, the probability of finding the electron there drops to zero.

Saying an electron travels every possible trajectory is really just one of several interpretations of quantum theory. The theory only gives us the probabilities of observing certain results; it doesn’t explain what the particles actually did to produce those results.

question is flawed, electrons don’t move at the speed of light. photons which do move at the speed of light in a vaccum (c), have virtual mass given the potential to convert via the equation e=mc2, but no real mass.

The electron is both a wave and a particle. Waves do not have a single position, but are spread out over space. Particles do have a position, and it is only by examining the electron that we make it determine that it is a particle alone and not a wave. It is not that the electron actually is in every position, but that its wave field spreads across a wide area and can be experimentally detected as long as the experiment is set up to find the wave portion of the electron’s nature rather than the particle portion. It sounds as if you have already read about the Einstein-Podulsky-Rosen thought experiments, and those involving a receiving screen and a two-slit set up have been performed and have verfied the theory of wave-particle duality. If you want to know how an object can simultaneously be two seemingly mutually exclusive things (both a wave and a particle) I think the only way to answer that question is with extensive mathematical equations that will still not really help you visualize the concept.

it does not REALLY do that (travel through every possible trajectory).

its wave function is affected by the environment. that wave function is a measure of the probality to find the electron at a given location.

what typically happens when the electron “follows a path” (well, a path does not really exist in quantum mechanics, at best you’d have an initial position and a final position, but you could’nt say anything for the in-between bit), is that the wave function cancels out in all regions of space, except in some, where you can indeed find the electron, say after an experiment.

hope this helps at least a bit