Photomagneton
Encyclopedia
The photomagneton is a theoretical treatment of the unitary group
in quantum field theory
and quantum chemistry
that effectively describes the experimentally observed inverse Faraday effect
. When circularly polarized light travels through a plasma, the angular momentum associated to the circular motion of the photons induces an angular momentum in the electrons of the plasma. This angular momentum induces an associated magnetic field
.
Exactly how this happens remains a subject of debate. For instance, if the so-called ghost field does not contribute to the free electromagnetic
energy
density in the plasma, then the electron must couple to something like a complex
electric field. However, if the field induces a finite magnetic field in the absence of matter, then the implication may be a finite photon
rest mass.
Unitary group
In mathematics, the unitary group of degree n, denoted U, is the group of n×n unitary matrices, with the group operation that of matrix multiplication. The unitary group is a subgroup of the general linear group GL...
in quantum field theory
Quantum field theory
Quantum field theory provides a theoretical framework for constructing quantum mechanical models of systems classically parametrized by an infinite number of dynamical degrees of freedom, that is, fields and many-body systems. It is the natural and quantitative language of particle physics and...
and quantum chemistry
Quantum chemistry
Quantum chemistry is a branch of chemistry whose primary focus is the application of quantum mechanics in physical models and experiments of chemical systems...
that effectively describes the experimentally observed inverse Faraday effect
Faraday effect
In physics, the Faraday effect or Faraday rotation is a Magneto-optical phenomenon, that is, an interaction between light and a magnetic field in a medium...
. When circularly polarized light travels through a plasma, the angular momentum associated to the circular motion of the photons induces an angular momentum in the electrons of the plasma. This angular momentum induces an associated magnetic field
Magnetic field
A magnetic field is a mathematical description of the magnetic influence of electric currents and magnetic materials. The magnetic field at any given point is specified by both a direction and a magnitude ; as such it is a vector field.Technically, a magnetic field is a pseudo vector;...
.
Exactly how this happens remains a subject of debate. For instance, if the so-called ghost field does not contribute to the free electromagnetic
Electromagnetism
Electromagnetism is one of the four fundamental interactions in nature. The other three are the strong interaction, the weak interaction and gravitation...
energy
Energy
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...
density in the plasma, then the electron must couple to something like a complex
Complex number
A complex number is a number consisting of a real part and an imaginary part. Complex numbers extend the idea of the one-dimensional number line to the two-dimensional complex plane by using the number line for the real part and adding a vertical axis to plot the imaginary part...
electric field. However, if the field induces a finite magnetic field in the absence of matter, then the implication may be a finite photon
Photon
In physics, a photon is an elementary particle, the quantum of the electromagnetic interaction and the basic unit of light and all other forms of electromagnetic radiation. It is also the force carrier for the electromagnetic force...
rest mass.