Why can't we exceed the speed of light?

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The important thing to know about faster-than-light travel and communication is that it is theoretically possible given a source of energy that violates current understanding of physics. At the moment, the Laws of Thermodynamics state that energy and matter are finite in the universe; neither can be created or destroyed, only changed in their state. Einstein's famous equation E = mc^2 states that as a particle approaches the speed of light, its mass increases, and therefore it requires more energy to continue acceleration. To approach the speed of light, an object would require an infinite source of energy; infinite mass can only be accelerated by infinite energy. This does not preclude theoretical particles such as tachyons, which are hypothesized to already travel faster-than-light, but all physical matter is prevented from this acceleration by physics. Recently, scientists thought they had successfully accelerated a beam of neutrinos faster than the speed of light, but this measurement was found to be the result of faulty equipment. Until an energy source is found that creates energy instead of transforming it, faster-than-light travel is scientifically impossible.

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