What determines the direction of a photon?

So one would need to consider the whole process. In that case, the direction of the emission is governed by the condition of the initial photon and electron prior to the absorption of the first photon. One can compute the propability distribution for all the possible directions that the last photon can be radiated.

Does a photon travel in all directions?

In contrast, light waves can travel through a vacuum, and do not require a medium. As a wave travels from a source, it propagates outward in all directions. Therefore, it fills a space given approximately by the surface area of a sphere.

Can photons change direction?

A photon is a quantum mechanical elementary particle and follows quantum mechanical formulae, not classical ones. In quantum mechanics the only way an elementary particle can change direction is through an interaction with another elementary particle or field.

Do we really know what a photon is?

They’re real. We can make electrons (and positrons) out of photons in pair production. And you are made out of electrons and other particles that are equally real. Photons exist and best described as packets of energy or particles.

Do photons oscillate?

Photons are often described as energy packets. This is a very fitting analogy, as a photon contains energy that cannot be divided. This energy is stored as an oscillating electric field. These fields may oscillate at almost any frequency.

How do we know photons have no mass?

Why do photons have no mass? In short, the special theory of relativity predicts that photons do not have mass simply because they travel at the speed of light. This is also backed up by the theory of quantum electrodynamics, which predicts that photons cannot have mass as a result of U(1) -gauge symmetry.

Does photon always travel in a straight line?

Photons do not travel in straight lines. Quantum particles do not have trajectories as classical particles do. Photons do not propagate in all directions as a spherical wave does. Photons are not waves.

Do photons travel as waves?

Unlike a particle which has wave centers that create standing, longitudinal waves measured as mass, the photon is a packet of traveling waves. Therefore, it has energy but not mass.

What happens when 2 lasers collide?

Actually, when two laser beams (or any other kinds of light for that matter) collide, they do not stop each other. In fact, usually they behave as though the other is not there at all. This is because light is a wave, and usually waves cross each other without interacting.

Can a photon turn into an electron?

A photon can spontaneously degenerate into a particle with mass and its antiparticle in a process known as pair production. In this process, the energy of the photon is completely transformed into the mass of the two particles. For example, a photon can turn into an electron and an anti-electron.

What experiment proved the existence of photons?

I have seen it asserted that the Compton effect can also be explained using a wave model of light, though I’ve never read a good explanation of how that works, but it is generally agreed that the experiment that absolutely nails the existence of photons is the photon anti-bunching experiment by Kimble, Dagenais, and …

Is there only one photon?

Photons really only exist at the interactions of EM and material. In between EM is a wave. Hence the wave particle duality of light. However, from a point of view of Feynman diagrams you could be right.

How many possible polarization states does a photon have?

A photon has two possible polarization states. In the momentum representation of the photon, which is preferred in quantum field theory, a photon is described by its wave vector, which determines its wavelength λ and its direction of propagation.

What is the magnitude of the momentum of a photon?

Since p points in the direction of the photon’s propagation, the magnitude of the momentum is. The photon also carries a quantity called spin angular momentum that does not depend on its frequency. The magnitude of its spin is √2ħ and the component measured along its direction of motion, its helicity, must be ±ħ.

What is the difference between a photon and an electron?

Both photons and electrons create analogous interference patterns when passed through a double-slit experiment. For photons, this corresponds to the interference of a Maxwell light wave whereas, for material particles (electron), this corresponds to the interference of the Schrödinger wave equation.

What happens to mass when a photon is absorbed or emitted?

The energy of a system that emits a photon is decreased by the energy of the photon as measured in the rest frame of the emitting system, which may result in a reduction in mass in the amount . Similarly, the mass of a system that absorbs a photon is increased by a corresponding amount.