Two particles accelerating towards each other

AI Thread Summary
Two large objects, such as stars, accelerating towards each other cannot reach the speed of light due to the effects of relativistic mass increase. As they approach each other, their relative velocity asymptotically approaches the speed of light, but never actually reaches it. This phenomenon is known as mass dilation, which has been confirmed by experimental data. The gravitational force between the objects increases as they get closer, but this does not allow them to exceed light speed. Understanding these principles is crucial for anyone studying physics or engineering.
robocop
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So I'm new here, hopefully I'll post a lot more in the future. Anywho, not sure if this is the right place but I've been wondering about what would happen under a given scenario. Say that you have two large objects of mass such as 2 stars a substantial distance x away from each other. Take them initially at a state of rest and in a closed system. If you release them and allow them to freely accelerate to one another their speeds will continually increase from a neutral observant point. So, what happens if the objects are large enough and far enough away that they accelerate to the speed of light. I don't know what is stopping them from going faster, theoretically as they get closer the force attracting them should only increase and it's not like the force goes away as they get closer.
 
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robocop said:
So I'm new here, hopefully I'll post a lot more in the future. Anywho, not sure if this is the right place but I've been wondering about what would happen under a given scenario. Say that you have two large objects of mass such as 2 stars a substantial distance x away from each other. Take them initially at a state of rest and in a closed system. If you release them and allow them to freely accelerate to one another their speeds will continually increase from a neutral observant point. So, what happens if the objects are large enough and far enough away that they accelerate to the speed of light. I don't know what is stopping them from going faster, theoretically as they get closer the force attracting them should only increase and it's not like the force goes away as they get closer.

Welcome to the PF. Material bodies cannot be accelerated to the speed of light, because their mass increases as they approach relativistic speeds:

http://math.ucr.edu/home/baez/physics/Relativity/SR/mass.html

.
 
so what would happen is that the relative velocity of the two bodies would asymptotically approach c. Is there experimental data to confirm that this would happen.
 
robocop said:
so what would happen is that the relative velocity of the two bodies would asymptotically approach c. Is there experimental data to confirm that this would happen.

Yes, lots. The subject is "mass dilation", so just do a google search on that to find lots of info.
 
berkeman said:
Yes, lots. The subject is "mass dilation", so just do a google search on that to find lots of info.

thanks for the help. I've got some knowledge from back when I was slacking off in engineering. Considering going back for EP, testing the waters so to speak.
 
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