All Questions
58
questions
3
votes
0
answers
80
views
Noether's Theorem in relativistic cosmologies [duplicate]
Is Noether's Theorem valid within the context of relativistic cosmology? If not, does this mean that the universe does not conserve energy on cosmological time and distance scales?
- 95.5k
1
vote
1
answer
63
views
Does vacuum decay create/destroy energy?
From what I understand, vacuum decay involves the release of potential energy, but where does this energy come from? Is it created in the moment and how does it affect the energy already present in ...
- 51
0
votes
1
answer
69
views
Why does the total gravitational potential in the universe exactly equal the total mass energy RIGHT NOW? [duplicate]
In the zero energy universe model, the gravitational field has negative energy, and this negative gravitational energy of all the distant mass exactly balances and cancels the positive mass-energy in ...
- 278
1
vote
0
answers
31
views
Infinite energy from net charge of a closed, finite universe
I have read that a net charge in a closed, finite universe would result in the electric field from the charge "winding" forever which would lead to infinite energy. However, wouldn't the ...
- 38
0
votes
1
answer
82
views
Spontaneous increase of vacuum energy?
If the vacuum energy of the universe is not at its minimum, that is, the universe is at a false/metastable vacuum state, then it could decay into the true vacuum state.
However, if our universe is ...
- 2,462
1
vote
5
answers
222
views
Why is all matter in the universe, not found at its lowest state of potential energy? [closed]
Preface: it may be of interest that I am a second year Biology student, with no experience in studying Physics and a very basic understanding of Mathematics. ...
- 69
0
votes
0
answers
57
views
What is the exact ratio of dark energy to mass?
I need to know the exact ratio between mass and dark energy (total dark energy in the universe / total mass in the universe). I could only find it to 2 decimal points (0.68). I need this to make this ...
2
votes
1
answer
392
views
Can there be negative energy within the classical general relativity?
The positive energy theorem (Witten and Yau were awarded the Fields medal in mathematics in part for their work on this topic.) says that "the gravitational energy of an isolated system is ...
- 1,580
-1
votes
2
answers
117
views
Could somehow the fundamental laws and symmetries of physics change or be broken? [closed]
There are some theoretical processes (like vacuum decay in quantum field theory) that could change the physical constants of the universe. Similarly, in inflation theory, various models predict that ...
- 2,462
1
vote
2
answers
262
views
Assuming that heat death or Big Freeze would be the final outcome for the universe, what would happen with energy?
According to Big Freeze, the universe will expand forever and it will reach a state of thermodynamical equilibrium. It is said that the temperature of the universe will reach an asymptotically ...
- 2,462
1
vote
2
answers
123
views
Could we estimate the total energy of the universe?
So I know that we do not know the sum of all energy in the universe, but why can we not just estimate with the following logic? (That I assume has some fatal flaw preventing anyone from guessing the ...
0
votes
2
answers
488
views
Is most of the energy in the universe potential energy?
So I asked a question about what would happen in regards to gravitational potential if I left earth and then vaporized it. The answer I got was that the Mass would still remain the same and even if ...
5
votes
1
answer
357
views
What percentage of the universe's energy is rotational kinetic energy?
Obviously there is constant exchange between different forms of energy, so presumably only an average could be estimated, assuming it is not an ill-posed question.
Also, even if a fairly precise ...
- 817
1
vote
2
answers
74
views
Why is there Energy? [closed]
I am a layman and this is my first ever question! Although, it is simplistic in nature, I hope that there is a beauty in its simplicity which could give a simple answer.
Alan Watts, the philosopher, ...
- 11
1
vote
0
answers
95
views
Why energy cannot be created nor destroyed if the Universe is still growing in size? [duplicate]
Why energy cannot be created nor destroyed if the Universe is still growing in size?There is creation of new space and infact this space is so energetic that causes 'Hubble flow' of matter...
- 1,815