If everything in the universe moved at the speed of light, would time exist? This is the question that Jon is puzzling over at this month's edition of Monthly Mailbag.
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Does time slow down for moving objects? Can you get objects with mass to the speed of light? And if everything was going at the same speed, would we even be able to tell that anything was moving?
Let us know how Jon did with this explanation and if you have a burning science question you'd like us to answer next month, stick it in the comments section below.
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