Jump to content

User:Mpatel/sandbox/Electromagnetic stress-energy tensor

From Wikipedia, the free encyclopedia

In physics, the electromagnetic stress-energy tensor is the portion of the stress-energy tensor due to the electromagnetic field. In free space (vacuum), it is given in SI units by:

where is the electromagnetic field tensor, is the metric tensor and is the permeability of free space

And in explicit matrix form:

,

with

Poynting vector ,
electromagnetic field tensor ,
metric tensor , and
Maxwell stress tensor .

Note that where c is light speed.

In cgs units, we simply substitute with and with  :

.

And in explicit matrix form:

where Poynting vector becomes the form:

.


The stress-energy tensor for an electromagnetic field in a dielectric medium is less well understood and is the subject of the unresolved Abraham-Minkowski controversy.

The element, , of the energy momentum tensor represents the flux of the αth-component of the four-momentum of the electromagnetic field, , going through a hyperplane xβ = constant. It represents the contribution of electromagnetism to the source of the gravitational field (curvature of space-time) in general relativity.

See also

[edit]