What is the significance of covariance in general relativity?

DiamondGeezer
Messages
126
Reaction score
0
Any relationship between mass, length and time in general relativity can be considered using tensors of Einstein's Field Equations which are independent of the coordinate system used and of the origin of that coordinate system

Is there a formal name for such coordinate independence and origin agnosticism? I assume there is.
 
Physics news on Phys.org
Last edited by a moderator:

Thread 'I don't see how a black hole's event horizon can be crossed'

OK, so this has bugged me for a while about the equivalence principle and the black hole information paradox. If black holes "evaporate" via Hawking radiation, then they cannot exist forever. So, from my external perspective, watching the person fall in, they slow down, freeze, and redshift to "nothing," but never cross the event horizon. Does the equivalence principle say my perspective is valid? If it does, is it possible that that person really never crossed the event horizon? The...
View full post »

Thread 'Synchronizing clocks in an inertial frame if light is anisotropic'

ASSUMPTIONS 1. Two identical clocks A and B in the same inertial frame are stationary relative to each other a fixed distance L apart. Time passes at the same rate for both. 2. Both clocks are able to send/receive light signals and to write/read the send/receive times into signals. 3. The speed of light is anisotropic. METHOD 1. At time t[A1] and time t[B1], clock A sends a light signal to clock B. The clock B time is unknown to A. 2. Clock B receives the signal from A at time t[B2] and...
View full post »

Thread 'Question about Parallel Transport'

In this video I can see a person walking around lines of curvature on a sphere with an arrow strapped to his waist. His task is to keep the arrow pointed in the same direction How does he do this ? Does he use a reference point like the stars? (that only move very slowly) If that is how he keeps the arrow pointing in the same direction, is that equivalent to saying that he orients the arrow wrt the 3d space that the sphere is embedded in? So ,although one refers to intrinsic curvature...
View full post »

Similar threads

B Prove that metric tensor is covariant constant
Replies
11
Views
1K
I Definition of time-independent scalar field in GR
Replies
4
Views
1K
I Coordinate System Transformation: Lowering/Raising Indices Explained
Replies
2
Views
2K
I What is a Covariant Relation? GR Problem Solution Explained
Replies
17
Views
2K
I Dirac comment on covariant derivatives
Replies
7
Views
1K
I Calculating Covariant Derivative of Riemann Tensor in Riemann Normal Coordinates
Replies
5
Views
2K
A Does the EP imply that a free-falling observer follows a geodesic?
Replies
3
Views
563
I What's the underlying frame of the Einstein's Field Equation?
4
Replies
186
Views
11K
I Does the metric in general relativity depend only on position because of the equivalence principle?
Replies
16
Views
2K
A Weyl tensor and coordinate acceleration
Replies
12
Views
2K

Hot Threads

Recent Insights

Back
Top