Two teams of physicists have discovered previously unseen exotic behaviour in sheets of carbon atoms. The teams have shown that electrons move through the sheets as if they have no rest mass. They have also observed a minimum value of conductivity for the sheets and an unusual form of the quantum Hall effect (Nature 438 197 and 201).
Go to Zz's thread https://www.physicsforums.com/showthread.php?t=99223that the electrons in graphene behave like relativistic particles that have no rest mass and travel at about 106 metres per second. Although this is a factor of 300 slower than the speed of light in vacuum, it is still much faster than the speed of electrons in an ordinary conductor. Moreover, the electrons in most conductors can be described by non-relativistic quantum mechanics, whereas the electrons in graphene need to be treated as relativistic particles called massless Dirac fermions.
Cosmo16 said:well, my chem teacher calls them masssless, which annoys me, which is why asked.
Well, there's alpha particles, beta particles, and gamma particles/rays. Gamma rays, are photons, electromagnetic radiation. Wave-particle duality. And photons kind of have mass and kind of don't... rest mass they do have.Cosmo16 said:ok, maybe it is gamma rays I am thinking of then, we were doing radiation, he was talking about it like it was a particle, but then he called it a ray, left me kinda confused.
Mk said:Well, there's alpha particles, beta particles, and gamma particles/rays. Gamma rays, are photons, electromagnetic radiation. Wave-particle duality. And photons kind of have mass and kind of don't... rest mass they do have.
It means that the electron does not have any physical mass or weight. This is in contrast to other subatomic particles, such as protons and neutrons, which have mass.
Electrons were determined to be massless through various experiments, including the Millikan oil drop experiment and the discovery of the electron's charge-to-mass ratio. These experiments showed that the electron has a very small mass compared to its charge.
Despite having no physical mass, electrons still have energy and momentum, which allows them to interact with other particles through electromagnetic forces. They can also gain mass through interactions with the Higgs field.
Yes, there are some theories that suggest that electrons may have a tiny, non-zero mass. However, these theories have not been confirmed through experiments and the current understanding is that electrons are indeed massless.
The masslessness of electrons is an important concept in physics and has implications in various fields, such as quantum mechanics and particle physics. It also helps explain certain phenomena, such as the behavior of electrons in a magnetic field.