Does a gravitating body have to undergo gravitational collapse?

In summary, the conversation discusses the possibility of a static body existing without undergoing gravitational collapse, even without considering degeneracy pressure. It is determined that, under certain conditions, the body would continually lose energy through radiation and eventually collapse. The concept of blueshift and redshift is also explored, but it is concluded that it is not a factor in the energy balance of the body. The conversation ends with a mention of a hypothetical setup to further illustrate the point.
  • #36
Agerhell said:
There are some problems with this explanation. For instance Stefan-Boltsmanns law states that the radiated power should go as the temperature to the power of four... That means that the people at the surface of the planet, that measures their temperature as 5.4 Kelvin would expect them to radiate 16 times as much energy then if the temperature had been 2.7 Kelvin. If the Stefan-Boltzmanns law holds for the people on the planet then the distant observer should be surprised that the planet radiates 8 times as much energy as a black-bodyradiator at 2.7 Kelvin should... Hmmm now I am somewhat confused...
Hmm, I think that most straight forward explanation is hidden in units of http://en.wikipedia.org/wiki/Stefan%E2%80%93Boltzmann_constant" . In base units it has seconds cubed in denominator. So it should be reduced (divided) by time dilation factor cubed. That can account for apparent reduction of intensity by factor of 2^3.
 
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<h2>1. What is gravitational collapse?</h2><p>Gravitational collapse is the process by which a massive object, such as a star or planet, collapses under its own gravitational force. This can occur when the internal pressure of the object is no longer able to counteract the force of gravity.</p><h2>2. What causes a gravitating body to undergo gravitational collapse?</h2><p>A gravitating body undergoes gravitational collapse when its mass is great enough to create a strong gravitational force that overcomes the internal pressure of the object. This can happen when the body runs out of fuel or when it is extremely massive.</p><h2>3. Is gravitational collapse a common occurrence?</h2><p>Gravitational collapse is a natural process that occurs in the universe, but it is not a common occurrence on a human timescale. It typically occurs in very massive objects, such as stars, and can take millions or even billions of years to complete.</p><h2>4. What happens during gravitational collapse?</h2><p>During gravitational collapse, the massive object begins to shrink in size as its internal pressure decreases. This causes the object's density and temperature to increase, leading to the formation of a compact object, such as a white dwarf, neutron star, or black hole.</p><h2>5. Can gravitational collapse be prevented?</h2><p>Gravitational collapse is a natural process that cannot be prevented. However, the effects of gravitational collapse can be mitigated by understanding and studying the process, and potentially finding ways to control or harness the energy released during the collapse.</p>

1. What is gravitational collapse?

Gravitational collapse is the process by which a massive object, such as a star or planet, collapses under its own gravitational force. This can occur when the internal pressure of the object is no longer able to counteract the force of gravity.

2. What causes a gravitating body to undergo gravitational collapse?

A gravitating body undergoes gravitational collapse when its mass is great enough to create a strong gravitational force that overcomes the internal pressure of the object. This can happen when the body runs out of fuel or when it is extremely massive.

3. Is gravitational collapse a common occurrence?

Gravitational collapse is a natural process that occurs in the universe, but it is not a common occurrence on a human timescale. It typically occurs in very massive objects, such as stars, and can take millions or even billions of years to complete.

4. What happens during gravitational collapse?

During gravitational collapse, the massive object begins to shrink in size as its internal pressure decreases. This causes the object's density and temperature to increase, leading to the formation of a compact object, such as a white dwarf, neutron star, or black hole.

5. Can gravitational collapse be prevented?

Gravitational collapse is a natural process that cannot be prevented. However, the effects of gravitational collapse can be mitigated by understanding and studying the process, and potentially finding ways to control or harness the energy released during the collapse.

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