I Gravitational Waves from Vanishing Sun: What Happens?

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The discussion centers on the hypothetical scenario of the Sun disappearing and its implications for gravitational waves and general relativity. Participants emphasize that such a scenario violates the conservation of mass-energy and local conservation of stress-energy, making it a poorly formed question. They argue that imagining the Sun's sudden disappearance lacks physical meaning and leads to fantastical outcomes. The consensus is that any meaningful discussion must adhere to the laws of physics. Ultimately, the thread concludes that without a valid premise, the inquiry cannot be addressed.
Zugr
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Classic question of the Sun disappearing into the aether, with General Relativity in mind.
For some time I was wondering, what would happen if the Sun just disappeared like someone hit the delete button in Universal Sandbox. Specifically, what kind of gravitational waves will be produced in the wake of such an event?
Would the law of conservation of Mass-Energy be miraculously conserved by the Gravitational waves? Would whatever outcome be incompatible with GR? Would they just rip a hole in the fabric of spacetime and create a black hole? (probably the most likely outcome)
 
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Zugr said:
For some time I was wondering, what would happen if the Sun just disappeared like someone hit the delete button in Universal Sandbox.
You cannot describe that happening in general relativity because it violates local conservation of stress-energy, which is baked into the equations. So there is no answer to your question.
 
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The best answer is that the question is poorly formed.

There is no physical meaning to 'the sun simply disappears', so any effect from such a fantastical premise is also fantastical.

[ EDIT ] D'oh! Ibix got the early worm.
 
DaveC426913 said:
The best answer is that the question is poorly formed.

There is no physical meaning to 'the sun simply disappears', so any effect from such a fantastical premise is also fantastical.

[ EDIT ] D'oh! Ibix got the early worm.
Fair enough, I was imagining a scenario in which one moment, everything is normal, and then the next, all the particles that constitute the Sun are no longer there, only leaving the curvature in spacetime that will probably attempt to ‘right itself’ since there is no longer any mass or energy to curve it.
Though I’m probably extrapolating too much from imagining spacetime as a literal fabric.
 
Zugr said:
I was imagining a scenario in which one moment, everything is normal, and then the next, all the particles that constitute the Sun are no longer there
As has already been said, this would violate local conservation of stress-energy. It is pointless to imagine a scenario that violates the laws of physics, and then ask what the laws of physics say about them.

You will need to come up with a scenario that doesn't violate the laws of physics if you want to discuss it here.

This thread is closed.
 
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