GRT: Wrong Picture of Basic Cosmology?

  • Thread starter jensel
  • Start date
  • Tags
    Picture
In summary, the conversation discusses a video from Stanford University on basic cosmology and GRT. The speaker expresses confusion about the relationship between coordinates and distance, as well as the concept of an expanding universe. They question whether the expansion of the universe means that the meter-scale is involved and whether the energy-momentum tensor creates new space rather than just deforming it.
  • #1
jensel
22
0
Hello,

I hope you can help me. I thought I have an idea about GRT but I found this about about the basic cosmology. It is a link to a video from Stanford Univerisity. In short words: Susskind seems to confuse coordinates with distance. I can't understand that he seems to talk about defined coordinates and then about relativity. He seems to have a view that an expanding universe means that the meter-scale is involvolved.
If you have a sphere, for example, you will have a sphere. You will have physics which is locally not depending from the "geometry" given. A meter-scale is a meter-scale, there is no change in time.

I am confused.


 
Last edited by a moderator:
Physics news on Phys.org
  • #2
I can give myself a first answer. I have a bacic misunderstanding of GRT. Since the velocity of light is a constant the expansion of the universe is not bending the let's say meter-scale but a real expansion. An object real get's farer away from every point in the universe in the long scale terms. I find this really strange since it means that the energy-momentum tensor really creates new space, not just deforms it, right?
 

1. What is GRT?

GRT stands for General Relativity Theory. It is a theory of gravity proposed by Albert Einstein in 1915 that describes how matter and energy interact with the fabric of space and time.

2. What is the "wrong picture" of basic cosmology in GRT?

The "wrong picture" refers to the fact that GRT does not fully explain the dynamics of the universe on a large scale, particularly the expansion of the universe. This led to the development of the Big Bang theory and the concept of dark energy.

3. How does GRT differ from classical mechanics?

GRT differs from classical mechanics in that it takes into account the curvature of spacetime and the effects of gravity on the motion of objects. Classical mechanics, on the other hand, only considers the effects of forces on the motion of objects.

4. Does GRT have any limitations?

Yes, GRT has limitations in explaining the behavior of matter and energy at the smallest and largest scales. It does not incorporate quantum mechanics, which is necessary for understanding phenomena at the subatomic level, and it does not provide a complete understanding of the universe at a cosmic scale.

5. How has GRT impacted our understanding of the universe?

GRT has greatly impacted our understanding of the universe by providing a new perspective on the nature of gravity and its effects on the universe. It has also led to the development of other theories, such as the Big Bang theory and the concept of black holes, which have greatly expanded our understanding of the universe.

Similar threads

I How many meter sticks are there in this length contraction reasoning?
    • Special and General Relativity
Replies
12
Views
806
B Question about Morin's time dilation explanation
    • Special and General Relativity
3
Replies
73
Views
2K
I Black Hole: Knock on the horizon
    • Special and General Relativity
Replies
34
Views
1K
B Lagrangrian and Hamiltonian mechanics: A historical picture
    • Classical Physics
Replies
7
Views
1K
I Connection b/w curvature and gravitational field-removing coordinate transformations
    • Special and General Relativity
2
Replies
40
Views
2K
I Gravity transition directly at the underside of a "shell planet"
    • Special and General Relativity
Replies
2
Views
772
I Invariance of Diff. Line Elems. in Hartle's Gravity: Intro to GR
    • Special and General Relativity
Replies
11
Views
1K
A Continuation of Coordinates Across Black Hole Horizons
    • Special and General Relativity
Replies
5
Views
889
I Has anyone measured the speed of light in one direction?
    • Special and General Relativity
2
Replies
45
Views
3K
B "Spacetime Physics" by Taylor and Wheeler
    • Special and General Relativity
Replies
32
Views
4K

Hot Threads

Recent Insights

Back
Top