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Suppose a device or object were traveling at or near the speed of light, and fission or fusion occurred while in this state of motion, creating an enormous blast, what would occur? Would this cause an acceleration of the objects or particles immediately in front of this blast? Or would some other event occur that I am unfortunately unaware of?

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What happens after the blast does not depend on the speed of the object - it is the principle of relativity.

Assuming that the object moves at 9/10 of the speed of light and that the blast accelerates the particles at 1/10 of the speed of light in all directions, the 'at rest' observer would see the particles in front of the object moving at a speed of:

$$ \frac{\frac{9}{10} + \frac{1}{10}}{1+\frac{9}{10}\frac{1}{10}} = \frac{100}{109} = 0.917 c $$

and the particles behind the object moving at the speed of:

$$ \frac{\frac{9}{10} - \frac{1}{10}}{1-\frac{9}{10}\frac{1}{10}} = \frac{80}{91} = 0.879 c $$

From the point of view of an observer on the object itself all particles will move with the same $1/10 c$ speed.

If the blast accelerates particles in only a certain direction this will accelerate the object in the opposite direction. This acceleration - when seen by the 'at rest' observer - will depend on its direction, because at relativistic speed the inertia depends on the direction of the applied force.

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Thanks! That answered part of my question, which, now that you have answered, seems really obvious, the equal reaction in the form of deceleration that is. The other part, which I did not explain properly, is what would the actual affect be of such a blast on the space directly around it? Would it have the potential to cause some sort of rift? Or would the energy simply dissipate? – Max Ritz Dec 9 '13 at 19:35
I am not sure what are you asking - what do you mean by 'rift'? Again, the fact that the explosion occurs on an object moving with high speed does not make any difference on its effect. – MiMo Dec 9 '13 at 19:46
Okay, thank you, I apologize for the vague terms, but you answered my question. I tend to lean towards the effects of light on us, as well as how we view it, so this is a little bit different for me. – Max Ritz Dec 9 '13 at 20:11

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