@doctroid @ZachWeinersmith Einstein's theory of relativity describes time dilation as someone near the speed of light experiences time differently from an observer on earth; a few minutes for them could be a few hours for us. If you were to travel at the speed of light, you'd think your trip was instantaneous, while a great deal of time would have passed on earth. Speed = distance / time, if you divide by 0 you get ∞. We don't observe this, so light must be bending in our universe of space time.
@quirk @ZachWeinersmith As someone with a doctorate in physics, I can tell you your understanding is incorrect. For one thing, nothing prior to the last sentence has anything to do with curvature, so the last sentence doesn't follow. And we do observe light behaving in exactly the way you describe, curvature or no curvature.