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If in the future a spaceship can accelerate to nearly the speed of light, will it encounter any kind of resistance/drag from the spacetime in front of it not being able to bend/warp fast enough around it?

It is my understanding that as an object accelerates, its mass will increase and this increase in mass should result in the object having more gravity, and this gravity will continue to increase as the object's speed increases. The creation of more and more gravity should result in an increased area of spacetime surrounding the object being bent/warped.

So, if there is a limit to how fast spacetime can bend/warp around an accelerating object, along with an increased area of spacetime being affected by an accelerating object's increased gravity, will this spaceship start to heat up and begin to melt the faster it accelerates?

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  • $\begingroup$ Photons emit from atoms in picoseconds to nanoseconds. $\endgroup$ Oct 5, 2018 at 15:07
  • $\begingroup$ Realize that the object's rest mass won't increase-- just the mass as perceived by objects traveling at a different speed. It's not really "spacetime in front of it", but rather actual particles that will now hit the ship at tremendous speeds. $\endgroup$
    – user21
    Oct 7, 2018 at 18:13

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Changes in the bending of spacetime propagate through spacetime at the speed of light. If I wave my hand thus the (very, very, very tiny) changes to spacetime will propagate outwards as gravitational waves at the speed of light and won't reach the Sun for 8 minutes.

No matter how massive an object or how great the acceleration, spacetime elsewhere only "feels" that acceleration after it has passed into the acceleration's lightcone.

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I have nothing to add to Mark Olson's answer except to point out that there are far more severe problems to contend with if you want to have a spaceship travelling at highly relativistic speeds

The cosmic microwave background will be blue shifted, boosted and beamed such that it might become a hazardous source of X-rays/gamma rays. Of course these problems would be much, much more severe should you fly towards anything brighter - like another star!

Secondly, cosmic dust and debris is going to become a serious problem. Any relativistic mass increase your ship manages will be mirrored by an increase in the kinetic energy of anything that runs into you (from the point of view of the rest frame of the ship).

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