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Katamari
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I understand energy mass equivalence, but when mass is changed to energy what happens to it's gravitational field?
Exploring Mass-Energy Equivalence and Its Impact on Gravitational Fields
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In summary, the gravitational field of a system can change over time due to the evolution of the system, but for an observer far away, the field appears constant. In general relativity, the source of the gravitational field is the stress-energy tensor, not just mass. However, there are scalar measures of mass-energy that are conserved in specific types of spacetimes, such as ADM and Bondi mass. Therefore, when mass is converted to energy, the gravitational field may change for an observer far away, but in an asymptotically flat spacetime, the distant, static field is determined by the system's ADM or Bondi mass.
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Bill_K
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Nothing. Stays the same. Whatever form the 'energy' takes: kinetic energy of the decay products, photons, etc, all those things are sources of gravity also. At least initially until things fly apart, the gravitational field will be the same.
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Dale
Mentor
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Mass is not the source of the gravitational field. The source of the gravitational field is the stress energy tensor:
http://en.wikipedia.org/wiki/Stress–energy_tensor
The mass only gravitates in the first place because it has a lot of energy.
http://en.wikipedia.org/wiki/Stress–energy_tensor
The mass only gravitates in the first place because it has a lot of energy.
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Mentz114
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I think the radiation would have to be kept in a perfectly reflecting box, or the gravitational field would change for a nearby observer. If the matter and antimatter are in the box, then anihilate, the field produced by the box and contents would not change. Pedantic is my middle name.
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Katamari said:
Even in Newtonian gravity, without conversion of mass to energy, the gravitational field of a system can change when the system evolves over time. For example, the gravitational field of the earth-moon system changes as they orbit around their common center of mass. However, those changes fall off quickly with distance, so an observer who is far away compared to the size of the system observes a constant field, equal to the field that would have been produced by a single particle with the same total mass.
In GR, there is no uniquely defined measure of mass-energy that is conserved in all spacetimes. As DaleSpam pointed out, it's the stress-energy tensor that is really fundamental in GR, not mass-energy. However, there are scalar measures of mass-energy such as ADM and Bondi mass that are conserved in specific types of spacetimes, such as asymptotically flat spacetimes. The distant, static field of a system in an asympotically flat spacetime is determined by its ADM or Bondi mass in exactly the way you would think. ADM and Bondi "mass" include both mass and energy (because otherwise they wouldn't be conserved).
So the short answer to your question is yes if you're talking about the distant, static field, in an asymptotically flat spacetime, and no otherwise -- which is not that different from the Newtonian answer.
-Ben
FAQ: Exploring Mass-Energy Equivalence and Its Impact on Gravitational Fields
What is mass-energy equivalence?
Mass-energy equivalence is a concept in physics that states that mass and energy are equivalent and can be converted into each other. This is described by Albert Einstein's famous equation, E=mc^2, where E represents energy, m represents mass, and c represents the speed of light.
How does mass-energy equivalence impact gravitational fields?
According to Einstein's theory of general relativity, mass and energy are two components of the same thing, known as spacetime. This means that mass and energy can both cause distortions in the fabric of spacetime, which is what we perceive as gravitational fields. Therefore, mass-energy equivalence has a direct impact on gravitational fields.
Can mass be converted into energy and vice versa?
Yes, mass and energy can be converted into each other. This has been demonstrated by nuclear reactions, such as nuclear fusion and fission, where a small amount of mass is converted into a large amount of energy. This principle is also used in technologies such as nuclear power plants and nuclear weapons.
How does mass-energy equivalence relate to the concept of black holes?
Black holes are objects with extremely strong gravitational fields, so strong that not even light can escape from them. According to mass-energy equivalence, the immense amount of mass concentrated in a black hole is also equivalent to an immense amount of energy. This energy is what creates the strong gravitational pull of a black hole.
Is mass-energy equivalence a proven theory?
Yes, mass-energy equivalence is a well-established theory in physics. It has been confirmed through numerous experiments and observations, and is an integral part of modern physics, particularly in the field of nuclear physics and astrophysics.