All Questions
15
questions
1
vote
2
answers
117
views
Curvature of space from approaching gravity sources affecting observations of expansion
Since gravity curves space, I wonder how the locally increasing density of matter and energy due to the current galactic mergers with the Milky Way affects our perception of the universe.
Basically, ...
0
votes
1
answer
77
views
Why redshift of light occurs between galaxies only? [duplicate]
Edwin Hubble discovery of redshift of distant galaxies make me wonder why is this phenomenon only occurs when object is further away, is it possible that redshift happens in short distance too such as ...
- 13k
1
vote
0
answers
32
views
If time slows in the presents of gravity, how does the conclusion that the universe’s expansion is accelerating account for this?
I am sure there is a simple explanation for this and I’m not a physicist so hoping someone here can help answer this for me.
Time is retarded by gravitational field. Expansion in all directions ...
- 11
-5
votes
1
answer
72
views
Could gravitational waves give an illusion of an expanding universe? [closed]
Could the effect of “expanding” gravity (gravitational waves spreading at the speed of light) as it travels through space (and therefore becomes less local) red-shift all EM waves and thus give us ...
0
votes
2
answers
81
views
Is the universe expanding?
If spacetime is curved by object with mass, just like the sun curves space time and so makes the planets orbit around it and will eventually in time make them crash towards it then shouldn't the ...
2
votes
1
answer
158
views
Isn't A Singularity Inevitable Given Infinite Time?
I am not a physicist but this is a question I've been trying to find the answer to for years and no answer I've been given has satisfied me.
It's my understanding that gravity affects all matter all ...
- 123
2
votes
1
answer
510
views
Why doesn't the universe collapse under its own gravity?
Is the reason the universe doesn't collapse into itself due to gravity because there is an infinite amount of bodies in infinite space, therefore there is an infinite amount of gravitational pull on ...
- 21
-4
votes
3
answers
869
views
Can the fabric of space-time be contoured into hills instead of just wells? [closed]
Einstein's general theory of relativity states that gravity is the distortion of space-time into gravity wells. In order to illustrate this, a flat plane is used to represent undistorted space-time ...
- 1,066
2
votes
1
answer
102
views
Hubble bubble and the shell theorem?
According to the Hubble bubble theory a local void could explain deviations of the Hubble constant for measurements in close vicinity to out local group compared to the global Hubble constant and ...
-1
votes
1
answer
193
views
Is space time curvature an effect of "slowed" local expansion? - Is a gravity field 'drag' in the cosmic expansion?
I've been trying to intuit what gravity is actually doing in respect to spacetime for a while. I'm familiar with the technical descriptions the relevant equations present but I'm trying to form more ...
1
vote
0
answers
70
views
As space-time expands between two stars, what happens to the gravitational potential energy seemingly lost as U~1/r => ZERO.?
As the space-time between two stars grows (the accelerating expansion of the universe) the gravitational potential energy between two stars is reduced as 1/r -> ZERO (r is the distance between stars).
...
3
votes
2
answers
3k
views
How does critical density affect the expansion of the universe if gravity is the curvature of space-time?
From what I know there are three scenarios about the end and expansion of the universe that all depend on the concept of critical density:
If the matter of our universe is above critical density, the ...
- 453
4
votes
1
answer
288
views
Would order 1AU metric expansion of space begin if the solar system were not inside a galaxy?
In this question I describe the >30 years of laser ranging between lasers on Earth and the retroreflector arrays on the Moon. Amazingly, after comparing this data to simulation of all of the orbital ...
- 6,273
2
votes
3
answers
311
views
Gravity's force on space
Here is a quote from Brian Greene, The Fabric of the Cosmos: Space, Time, and the Texture of Reality, p. 273:
“The early universe provided an arena in which gravity exerted its repulsive side with ...
- 375
3
votes
0
answers
109
views
When spacetime expands to the point where galaxy clusters are not observable, will there by any interaction?
It's my understanding that in a few billion years, clusters of galaxies won't be able to directly observe one another due to the expansion of spacetime overcoming gravity between those clusters. ...
- 131