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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.
In summary, the conversation discusses the idea of whether or not photons contribute to Earth's gravitational field. It is concluded that photons do not have mass and therefore cannot have a gravitational field. The Earth is also in thermal equilibrium, meaning that the incoming solar radiation is balanced by outgoing radiation. Overall, the conversation highlights the relationship between energy, mass, and the curvature of space-time.
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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.
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clustro
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?
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?
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D H said:
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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?
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?
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clustro said:
Yes. You already get the gist of it:
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.
Photons carry energy. Energy, like mass, curves space-time. (Mass is energy.)
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i see , incoming energy= outgoing energy
1. What is the gravity field of the earth?
The gravity field of the earth refers to the force of gravity exerted by the earth on objects near its surface. It is what keeps objects on the earth's surface from floating away into space.
2. How is the gravity field of the earth measured?
The gravity field of the earth is measured using a device called a gravimeter. This instrument measures the strength of the gravitational pull at a specific location on the earth's surface.
3. How does the gravity field of the earth affect objects?
The gravity field of the earth affects objects by pulling them towards the center of the earth. This force is what gives objects weight and determines their acceleration towards the earth's surface.
4. Is the gravity field of the earth the same everywhere?
No, the gravity field of the earth is not the same everywhere. It varies depending on factors such as altitude, latitude, and the density of the materials beneath the surface. This is why objects may weigh slightly more or less in different locations on the earth.
5. Can the gravity field of the earth change?
Yes, the gravity field of the earth can change over time. It can be affected by natural events such as earthquakes and volcanic eruptions, as well as human activities such as mining and construction. However, these changes are usually very small and not noticeable to humans.