system
Given the following post, respond as if you're commenting on Reddit:
human
Why is light the only thing that travels at the speed of light?

I know that there is nothing that goes faster than the speed of light. But why is light the only thing that goes that fast? Is there anything that goes just as fast as light?
gpt
The thing is that the speed of light isn't just some arbitrary speed that light moves at and then nothing can go faster than it. You could say the speed of light (approx. 300,000 km/s) is like a universal "top speed." Anything without mass will travel at that speed, with electromagnetic waves (light) being the prime example. As Wrathchilde said, the current leading hypothesis on gravity is that it propagates at that same speed.