Does Earth's Gravitational Field Strengthen Upon Receiving Light from the Sun?

AI Thread Summary
The discussion centers on whether light from the Sun strengthens Earth's gravitational field. Participants clarify that photons, which are massless, do not contribute to gravitational fields, thus having a negligible effect on Earth's gravity. They emphasize that while photons carry energy, this energy does not lead to a buildup of mass on Earth. The Earth remains in thermal equilibrium, balancing incoming solar radiation with outgoing thermal radiation. Overall, the consensus is that incoming light does not significantly alter Earth's gravitational field.
cragar
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This may be a dumb question , but as light travels from the sun to Earth , each photon has its own gravitational field , so when the light hits Earth does the gravitational field of Earth become stronger.
 
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No. For one thing, the effect would be tiny. For another, it doesn't exist. The Earth is more-or-less in thermal equilibrium. In fact, the Earth as a whole is still cooling off from its formation 4.5 billion years ago.
 
DH... did you post in the right thread?

And cragar: I am pretty sure to have a gravitational field, you need mass. Photons don't have mass, so they don't have the field, and therefore can't contribute to Earth's gravity field.

of course, even if they had mass, you have to assume that all photons impinging upon the Earth actually stay on the earth, leading to a buildup of mass.

Seems weird, no? o_O
 
D H said:
No. For one thing, the effect would be tiny. For another, it doesn't exist. QUOTE]
What doesn't exist , okay so its tiny but its their .
 
clustro said:
DH... did you post in the right thread?

And cragar: I am pretty sure to have a gravitational field, you need mass. Photons don't have mass, so they don't have the field, and therefore can't contribute to Earth's gravity field.

of course, even if they had mass, you have to assume that all photons impinging upon the Earth actually stay on the earth, leading to a buildup of mass.

Seems weird, no? o_O
You don't need mass , to create a gravitational field , In relativity mass or energy bends space time , and if the field associated with the photon goes away where does the field go or the energy , doesn't the energy from the photon still create a field .
 
clustro said:
DH... did you post in the right thread?

Yes. You already get the gist of it:
ou have to assume that all photons impinging upon the Earth actually stay on the earth, leading to a buildup of mass.
The Earth is in thermal equilibrium. The incoming solar radiation is balanced by outgoing radiation, mostly thermal. Think of the Earth as an energy-neutral frequency converter.

And cragar: I am pretty sure to have a gravitational field, you need mass. Photons don't have mass, so they don't have the field, and therefore can't contribute to Earth's gravity field.
Photons carry energy. Energy, like mass, curves space-time. (Mass is energy.)
 
i see , incoming energy= outgoing energy
 
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