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Name: Juan
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Do virtual particles travel faster than light?

I think the simple answer is that it depends on whether or not the virtual particle has mass. If it is massless, then it would have a velocity of the speed of light. If it has mass, then it would travel as some speed less than that of light. If they could travel faster than light (or if massive ones could travel at the speed of light), then I would expect some really bizarre breaking of causality and energy conservation.

Virtual particles are invoked in modern field theory as a way of describing how real particles interact. The simplest intuitive idea is that if these particles were traveling at faster than light speeds, then there would be severe cause and effect problems.

Michael S. Pierce

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