Linked Questions

0 votes
1 answer
332 views

What are the properties of metric tensor? [duplicate]

It's frequently said that graviton has spin-2, so its wave function should have $5$ independent components. The metric tensor has $n^2=16$ components, but it obeys the following property: \begin{...
JavaGamesJAR's user avatar
0 votes
1 answer
283 views

Why gravitational waves have 2 possible polarizations? [duplicate]

I was under the impression that light waves have 2 polarizations because even if the photon is spin 1, the photon is massless which imposes additional constraints. In the case of gravity, it is ...
Mauricio's user avatar
  • 5,476
6 votes
4 answers
7k views

Degrees of freedom of the graviton versus classical degrees of freedom

I have a puzzle I can not even understand. A graviton is generally understood in $D$ dimensions as a field with some independent components or degrees of freedom (DOF), from a traceless symmetric ...
riemannium's user avatar
  • 6,541
10 votes
3 answers
5k views

Counting degrees of freedom of gauge bosons

Gauge bosons are represented by $A_{\mu}$, where $\mu = 0,1,2,3$. So in general there are 4 degrees of freedom. But in reality, a photon (gauge boson) has two degrees of freedom (two polarization ...
user09876's user avatar
  • 817
3 votes
1 answer
1k views

Propagating degrees of freedom of graviton

What is the best way to see that the number of propagating degrees of freedom or gravitons in 3 dimensions is $0$ ? By graviton I mean the metric and NOT some topologically massive graviton that one ...
dbranes's user avatar
  • 73
4 votes
0 answers
506 views

Degrees of freedom in General Relativity

A way one counts degrees of freedom(i.e. independent entries of the metric tensor ) in General Relativity is this: one goes to the linearized version, vacuum solution, and he sees that there are two ...
Saladino's user avatar
  • 305
1 vote
0 answers
244 views

Notion of 'functional degrees of freedom' for the metric function in GR?

I have read through the numerous questions on 'degrees of freedom' in the metric tensor, and won't list them all here. However none of them address my question on 'functional' degrees of freedom in ...
Meep's user avatar
  • 3,979
0 votes
0 answers
185 views

How many independent degrees of freedom does the metric tensor have in vacuum (at every point)?

A field of metric tensors fully characterises the curvature of a vacuum space-time. (For example, the spacetime between some single point masses which are themself not part of the manifold) The metric ...
Scibo's user avatar
  • 93
1 vote
0 answers
173 views

Are gravitons possible in 2+1 spacetime dimensions?

Spin-1 massless particles are transverse waves, so they need at least three space-time dimensions to exists. As for gravitons, I think they are still not possible in three dimensions, and to reveal ...
Daniel Castro's user avatar
1 vote
1 answer
76 views

Why particles can have different number of degree of freedom in a 3D + 1T dimension?

Air molecule has $6$ degrees of freedoms: it can move up & down, left & right, front & back, rotate along $x$-axis, $y$-axis, $z$-axis. But I heard about graviton, a hypothetical particle ...
user6760's user avatar
  • 13k