Linked Questions
27 questions linked to/from Redshifting of Light and the expansion of the universe
14
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Have red shifted photons lost energy and where did it go? [duplicate]
I think the title says it. Did expansion of the universe steal the energy somehow?
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2
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3k
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Where does the energy go when light is redshifted? [duplicate]
Imagine a galaxy millions of lightyears away and, obeying Hubble's law, moving very quickly away from us.
Now imagine the same galaxy emitted a green photon in our direction (a photon with a ...
4
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1
answer
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Conservation of Energy in General Relativity [duplicate]
I recently heard about energy "not being conserved" in General Relativity and i had doubts. Is this true, cause the following questions deeply worry me if that is the case?:
Wasn't the whole point of ...
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2
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When the Cosmic Microwave Background radiation cools, where does the energy go? [duplicate]
I understand how photons can change wavelength via gravitational redshifting, but that doesn't seem to be what's going on with the CMB radiation. I've heard it explained as happening because of the ...
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1
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Conservation of Momentum and The Expansion of The Universe [duplicate]
As I understand it, the cosmological red shifting of light is one of the effects of the expansion of the universe. But as the wavelength of light increases, the momentum given by:
p = $\frac{h}{\...
- 121
3
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0
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Where does the energy of a redshifted photon go to? [duplicate]
When traveling through the vacuum, electromagnetic waves experience an increase of wavelength (redshift).
According to this equation:
$$E=\frac{hc}{\lambda}=h\nu$$
( Where, as we know, h is the ...
- 31
0
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1
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297
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Energy conservation in the redshifted light by expansion of the universe [duplicate]
I asked chat-gpt the same question, and this is her answer:
The energy of light that is redshifted due to the expansion of the universe doesn't disappear, it is simply transformed into other forms of ...
- 13
2
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0
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115
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Is red-shift a violation of the conservation of energy? [duplicate]
Light loosing frequency equals to a loss of energy as far as I understood.
So where does this energy go, given that the law of conservation of energy is correct?
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0
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1
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Energy conservation in Hubble Expansion [duplicate]
So space expands due to Hubble Flow. Some light is observed, which is seen to be red-shifted due to the space expansion. It is less energetic. Where did the energy go?
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0
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74
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Where does the energy from expanded light go? [duplicate]
The universe is expanding and light traveling through it also expands. Light with longer wavelengths have less energy so light is losing energy as the universe expands. Where does this energy go? Or ...
- 340
4
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0
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Where did the energy from the CMBR go? [duplicate]
Basically the title. The wavelength of light from the CMBR has expanded as the universe expanded and so it has lost energy since it is inversely proportional to the wavelength. Where did this energy ...
- 382
1
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0
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Why don't big bang photons conserve mass and energy? [duplicate]
A photon from the big bang has lost most of its momentum and energy. What does it push against? Does it break the 'laws' of conservation of energy and momentum? Is there any possibility that momentum ...
2
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0
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26
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When light gets red shifted by the expending universe it's energy decreases. What happens to that energy? [duplicate]
If a Photon of light is red shifted its wavelength increases and therefore its energy decreases. What happens to that energy as energy should be conserved right?
1
vote
0
answers
24
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When space expands where do the energy of the gravitational wave dissipate to? [duplicate]
I think it is safe to say that gravitational wave do not dissipate unless it met matter along the way imparting some of it's energy to cause some distortion or when it's frequency is stretched even ...
- 13.1k
34
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4
answers
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Is energy really conserved?
In high school I was taught energy was conserved. Then I learned that nuclear reactions allow energy to be converted into mass. Then I also heard that apparently energy can spontaneously appear in ...
- 2,784
25
votes
5
answers
8k
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Hubble's law and conservation of energy
If all distances are constantly increasing, as Hubble's law say, then lots of potential energies of form ~$\frac{1}{r}$ changes, so how is the total energy of the Universe conserved with Hubble's ...
- 5,301
22
votes
3
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Redshifted Photon Energy
A photon emitted from a receding source (Doppler redshift) has less energy when detected at an observer's location. Please explain the energy loss from the perspective of energy conservation.
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10
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3
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Do photons lose energy due to gravitational redshift? If so, where does the lost energy go? [duplicate]
In the gravitational redshift, the frequency of photons radiated from some source is reduced. As the energy of a photon is given by $\hbar\omega$, if the frequency is reduced where is the lost energy?
user21090
10
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1
answer
3k
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What is gravitational energy in general relativity?
In GR the curvature of spacetime "is gravity". This curvature is expressed via the Riemann tensor (or the Ricci tensor + Ricci scalar). The curvature is connected via the Einstein Field Equations with ...
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2
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What is the QUANTUM mechanical "explanation" for the "red shift?" [closed]
On another thread, users have asked for an explanation of the "red shift" of photons (the apparent loss of energy of photons due to the expansion of the universe.) All they ever got was a GENERAL ...
- 21
1
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3
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525
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Effect of expansion of space on CMB
Is it true that the expansion of space time cause the CMB to become microwaves from a shorter wavelength. If it is has the amplitude been increased?
Seeing as the amplitude has decreased; why hasn't ...
- 6,987
1
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3
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Red shifted photons lost energy in which form?
Red shifted photons lost energy in which form?
Photons which have experienced a change in frequency (red shift) due to gravity(or other red shifting affects), have necessarily lost energy, total ...
- 565
1
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3
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Are Photons Entangled with Gravity? [closed]
Part 1: A photon's wavelength is red-shifted by expanding space. Since $E=hf$ the photon imparts some of it's energy to the curvature of space, slowing the expansion of space ever so slightly. Is that ...
0
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4
answers
127
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Is it correct to say, any object has a huge amount of potential energy?
Let's say if it is a $ 1 kg $ metal ball.
Now if we consider it together with a planet some 500 light years away (or if we consider Neptune), then there is potential energy between this metal ball ...
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-3
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2
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258
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Does mass of universe at the moment of big bang changes compared to present day? [duplicate]
Empty space isn't empty as it can contain energy in terms of quantum fluctuation, so since inflation I like to know whether if the present day universe has put on weight?
- 13.1k
2
votes
1
answer
77
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Can expanding space stretch the wavelength of GWs? [duplicate]
I have read this question:
Redshifting of Light and the expansion of the universe
Now analogously, we could talk about GWs traveling in the empty voids of space, where the expansion of space is ...
- 29.3k
0
votes
1
answer
74
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Cosmological energy conservation
The expanding universe is gaining energy through increasing dark energy, and losing energy from red shift. Are these two effects comparable in magnitude?
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