All Questions
8
questions
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Does strongly gravitating object travel along geodesic of a background field？ [closed]
That test particles travel along the geodesic is assumed in the context of GR. But does it apply to strongly gravitating object, such as black hole in an expanding universe, binary neutron star, etc.? ...
- 619
2
votes
0
answers
60
views
Evolving energy density of a particle species in cosmology
Suppose you have a momentum distribution of some decoupled $X$ particles in the early universe $f(\mathbf{p})$ that is injected in (well above the electroweak scale so that degrees of freedom for all ...
- 499
3
votes
1
answer
199
views
Will the ever accelerating space expansion (like at the level of inflation) eventually break causality?
I have read this question:
requires that "for an action at one point to have an influence at another point, something in the space between the points, such as a field, must mediate the action&...
- 29k
1
vote
3
answers
202
views
What is the result that that differs by many orders of magnitude between QM and GR? [duplicate]
It is well known that QM and GR are deemed incompatible due to a discrepancy in some calculations which I have read can differ by large magnitudes. What are these calculations to which people are ...
- 145
1
vote
1
answer
85
views
Is the Large Number Hypothesis still a subject worth researching? [closed]
I've done some research on it for an essay competition of the Gravity research Foundation and shared it with other physicists but the response was very dismal in the sense that most physicists didn't ...
2
votes
1
answer
643
views
Does a hydrogen atom today have same mass as a hydrogen atom in the future?
Does an atom of hydrogen today have the same rest mass energy as an atom of hydrogen a billion years in the future?
Standard cosmology seems to tacitly make this assumption.
But surely one can only ...
- 5,925
4
votes
1
answer
101
views
If non-zero cosmological constant interpreted as a repulsive field, what would be the properties of this field's quanta?
If non-zero cosmological constant interpreted as a repulsive field, what would be the properties of the excitation of such field, i.e. the particle which serves as the field's quantum?
What would be ...
- 11.2k
2
votes
1
answer
2k
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Do atoms expand with universe? [duplicate]
Possible Duplicate:
Why space expansion affects matter?
Why does space expansion not expand matter?
As we know, the universe is expanding, galaxies are away from each other. But what about ...
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