- #1

Lelan Thara

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Hello, folks - here is a question that I have been pondering for about 20 years.

As I understand it, the Schwarzschild radius can be thought of as a measure of how much mass can fit within a given space before that space warps from gravity to such an extent that it acquires an event horizon and collapses into a black hole.

- Special relativity tells us that as a massive body accelerates, it's mass, as seen from a slower frame of reference, will increase. If the body could accelerate to the speed of light, it's relative mass would become infinite.

- General relativity tells us that the force of acceleration is equivalent to the force of gravity.

So, my question is - shouldn't any accelerating body have a finite speed below light speed at which its relativistic mass would surpass the SChwarzchild radius - causing the accelerating body to become a black hole?

This seems such an inescapable conclusion to me - is there something fundamental I am misunderstanding?

Science fiction often dwells on the problem of spacecraft traveling faster than the speed of light - if I am right, isn't this a moot point? If a spacecraft would become a black hole at a finite speed below light speed - what would be the theoretical implications for space travel? Do we have any idea what a rapidly moving black hole would be like? Do we have any sound theories on how spaces beyond an event horizon might be related to normal spacetime?

If we imagine travellers on this spacecraft - wouldn't they survive this gravitational (accelerational) collapse because their mass relative to the craft remains unchanged?

I apologize if the space travel parts of this question are too speculative. But I'd be grateful to hear what you folks have to say about my major question -

- if acceleration and gravitation are equivalent, shouldn't every accelerating body have a Schwarzschild radius?

(As usual, I must remind you I am a layman and ask you to indulge me with answers in plain English. Thanks.)

As I understand it, the Schwarzschild radius can be thought of as a measure of how much mass can fit within a given space before that space warps from gravity to such an extent that it acquires an event horizon and collapses into a black hole.

- Special relativity tells us that as a massive body accelerates, it's mass, as seen from a slower frame of reference, will increase. If the body could accelerate to the speed of light, it's relative mass would become infinite.

- General relativity tells us that the force of acceleration is equivalent to the force of gravity.

So, my question is - shouldn't any accelerating body have a finite speed below light speed at which its relativistic mass would surpass the SChwarzchild radius - causing the accelerating body to become a black hole?

This seems such an inescapable conclusion to me - is there something fundamental I am misunderstanding?

Science fiction often dwells on the problem of spacecraft traveling faster than the speed of light - if I am right, isn't this a moot point? If a spacecraft would become a black hole at a finite speed below light speed - what would be the theoretical implications for space travel? Do we have any idea what a rapidly moving black hole would be like? Do we have any sound theories on how spaces beyond an event horizon might be related to normal spacetime?

If we imagine travellers on this spacecraft - wouldn't they survive this gravitational (accelerational) collapse because their mass relative to the craft remains unchanged?

I apologize if the space travel parts of this question are too speculative. But I'd be grateful to hear what you folks have to say about my major question -

- if acceleration and gravitation are equivalent, shouldn't every accelerating body have a Schwarzschild radius?

(As usual, I must remind you I am a layman and ask you to indulge me with answers in plain English. Thanks.)

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