GR and its bending of space time

In summary, the conversation discusses the concept of space-time bending due to gravity and the possibility of mass popping into existence. It is explained that according to the theory, mass cannot simply appear and that changes in mass and energy can have an effect on curvature that propagates at the speed of light. The conservation of energy is also mentioned as a direct consequence of Einstein's Field Equations.
  • #1
loic patry
Hello
Maybe my question is dumb but is the bent of space time instant due to gravity?
If a mass pops into existence will space time be bent instantly ?
Intercations between forces are light speed but gravity is and is not a force depending on pov
 
Physics news on Phys.org
  • #2
loic patry said:
If a mass pops into existence will space time be bent instantly ?
The theory which says that mass* bends spacetime also says that mass cannot pop into existence.

*mass technically should be the stress energy tensor
 
  • Like
Likes vanhees71
  • #3
loic patry said:
If a mass pops into existence will space time be bent instantly ?
Mass or energy "just popping into existence" violates the conservation of energy. The conservation of energy turns out to be a direct consequence of Einstein's Field Equations, which are the things that describe curvature. So it is literally impossible to describe mass "just popping into existence" in general relativity.

Changes in the distribution of mass and energy can occur, such as two stars colliding. The effects of that change on curvature propagate outward at the speed of light (checking that statement is one of the jobs of the LIGO/VIRGO project).
 
  • Like
Likes vanhees71

Related to GR and its bending of space time

1. What is General Relativity (GR)?

General Relativity (GR) is a theory of gravity developed by Albert Einstein in the early 20th century. It explains how massive objects, such as planets and stars, affect the shape of space and the flow of time.

2. How does GR explain the bending of space-time?

According to GR, the presence of mass and energy in the universe causes space-time to curve. This curvature is what we perceive as gravity. Objects with more mass create a deeper curvature, which is why larger objects, like planets, have a stronger gravitational pull.

3. What evidence supports the theory of GR?

There are several pieces of evidence that support GR. Some of the most compelling include the bending of starlight around massive objects, the observations of gravitational waves, and the precise predictions of orbital paths of planets and other celestial bodies.

4. How does GR differ from Newton's theory of gravity?

Newton's theory of gravity, also known as classical mechanics, assumes that gravity is a force that acts at a distance between any two objects. GR, on the other hand, explains gravity as a curvature of space-time caused by the presence of mass and energy.

5. Can GR be applied to the entire universe?

Yes, GR is a universal theory that can be applied to the entire universe. It has been successfully used to explain the behavior of large-scale structures, such as galaxies and clusters of galaxies. However, it breaks down at the smallest scales, such as the quantum realm, where a different theory, quantum mechanics, is needed.

Similar threads

  • Special and General Relativity
Replies
14
Views
1K
  • Special and General Relativity
Replies
30
Views
736
Replies
62
Views
4K
  • Special and General Relativity
Replies
27
Views
4K
  • Special and General Relativity
Replies
3
Views
900
  • Special and General Relativity
Replies
12
Views
1K
  • Special and General Relativity
3
Replies
95
Views
4K
  • Special and General Relativity
Replies
13
Views
1K
  • Special and General Relativity
Replies
8
Views
528
  • Special and General Relativity
Replies
27
Views
886
Back
Top