How many physical polarization does a photon have?

An individual photon can be described as having right or left circular polarization, or a superposition of the two. Equivalently, a photon can be described as having horizontal or vertical linear polarization, or a superposition of the two.

What is the difference between a virtual photon and a real photon?

A more natural distinction between real and virtual photons is that a real photon is one that transfers empirically detectable energy, while virtual photons do not. In that picture, the response of the absorber is what gives rise to the ‘free field’ that in the quantum domain is considered a ‘real photon’.

How many spin states does a photon have?

Photon has spin one and because photons move with the light speed only two spin projections on their momentum vector are possible ; +1 and -1. It is a property of all massless particles with spin.

Is photon polarization the same as spin?

Photons, which are the quanta of light, have been long recognized as spin-1 gauge bosons. The polarization of the light is commonly accepted as its “intrinsic” spin degree of freedom. Thus, the photon spin is always only connected to the two circular polarizations.

Are virtual photons real?

Virtual particles are indeed real particles. Quantum theory predicts that every particle spends some time as a combination of other particles in all possible ways. In a hydrogen atom an electron and a proton are bound together by photons (the quanta of the electromagnetic field).

What is the difference between a virtual particle and a real particle?

“Real particles” are better understood to be excitations of the underlying quantum fields. Virtual particles are also excitations of the underlying fields, but are “temporary” in the sense that they appear in calculations of interactions, but never as asymptotic states or indices to the scattering matrix.

Can photons have spin 0?

Electrons and quarks (particles of matter) can have a spin of –1/2 or +1/2; photons (particles of light) can have a spin of –1 or +1; and Higgs bosons must have a spin of 0. Though particle spins are tiny, they have an impact on our everyday world. The spin property of photons allows us to create 3D movies.

Are virtual photons massive?

The probability amplitude for a virtual particle to exist tends to be canceled out by destructive interference over longer distances and times. As a consequence, a real photon is massless and thus has only two polarization states, whereas a virtual one, being effectively massive, has three polarization states.

Are all photons virtual?

Every photon will spend some time as a virtual electron plus its antiparticle, the virtual positron, since this is allowed by quantum mechanics as described above. The hydrogen atom has two energy levels that coincidentally seem to have the same energy.

What are the two types of polarization of a photon?

So there are two transverse polarization states of a photon in optics. One can call these two states “horizontal” and “vertical”. These two types of photons are “real” photons. The polarization vector of a static electromagnetic field can be parallel to the wave vector. You could call this a longitudinal polarization state.

What is the difference between a real and a virtual photon?

As a consequence, a real photon is massless and thus has only two polarization states, whereas a virtual one, being effectively massive, has three polarization states. Quantum tunnelling may be considered a manifestation of virtual particle exchanges.:235 ​

What is the quantum polarization state vector of a photon?

The quantum polarization state vector for the photon, for instance, is identical with the Jones vector, usually used to describe the polarization of a classical wave. Unitary operators emerge from the classical requirement of the conservation of energy of a classical wave propagating through lossless media…

What is the difference between SO(2) and polarization?

They are roughly different names for the same thing, the nuance differences are listed here: Polarizations describe the possible modes of photon. There are usually two kinds of basis people like to use: I) the defining representation basis of SO (2). People like to call this basis the linear mode (or linear polarization).

https://www.youtube.com/watch?v=n9-vrxW8Za0