All Questions
Tagged with universe energy-conservation
72
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Dark energy and conservation of energy in General relativity [duplicate]
i know that conservation of energy in general relativity has been discussed multiple times here at PE, a popular explanation on the topic is Sean Carroll's blog "Energy is not conserved" ...
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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?
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Expansion of Universe and validity of law of conservation of energy [duplicate]
It has been proved by the Red Shift that universe is expanding. But if the universe is actually expanding, it needs energy to do so. I also do not know that with expansion in universe if mass ...
2
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1
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How can the universe die if all energy is conserved?
So according to physics, because of the expansion of the universe, there will be a time in the future, where all that exists (maybe...quantum fields) will be so far away from each other that it will ...
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The gravitational field of all the distant mass exactly cancels the positive mass-energy in the universe. Why do they think so? [duplicate]
It is often said that the gravitational field has negative energy, and that this negative gravitational energy of all the distant mass exactly cancels the positive mass-energy in the universe.
Why do ...
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The expansion of universe releases vacuum energy
The quote below has been taken from the Wikipedia article on cosmological constant, https://en.wikipedia.org/wiki/Cosmological_constant.
Einstein included the cosmological constant as a term in his ...
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Are there any mathematically conceivable arrangements of an indeterministic universe that are not physically possible?
Are there any mathematically conceivable arrangements of this universe (particularly ones that respect its mass-energy content) that cannot in principle be achieved through its evolution in accordance ...
2
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Energy conservation and time uniformity
Reading Peter Atkin's book Four laws that drive the universe, I cannot see the link between time uniformity and conservation of energy the way it is tackled in this excerpt:
" Noether’s theorem, ...
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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 ...
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7
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Energy extraction from universe expansion? [duplicate]
I recently learned that energy is not conserved according to general relativity. Inspired, I went looking for a way to harness this interesting feature of the theory and came across an idea that ...
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How is energy in the universe constant? [duplicate]
We have been taught that the universe has a constant amount of energy but if energy can be converted into matter, how is it constant?
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What mechanisms could keep Universe at 0 energy?
In my understanding is right, there is no obvious guarantee of the conservation of energy on the cosmological scale. The expansion of space-time causes the red-shift of radiation and therefore the ...
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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...
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Is energy of universe constant? [closed]
First of all please do not flag this question as duplicate(I have read all the others like this one, this one and this one is just talking about observable universe. none of them talked in this ...
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Energy neither created nor destroyed. Then where energy comes from? [duplicate]
We are stating that energy neither be created nor be destroyed. Then where does it come from?
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