Physics education research, electronic materials, and the musings of Christopher Moore, Ph.D.
Physics education research, electronic materials, and the musings of Christopher Moore, Ph.D.
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I had a physics epiphony of sorts yesterday. I was thinking about the things I was reading in a book about relativity ("Why Does E=MC2") and what general relativity entails. Of course there is no absolute space, which would mean there is no absolute distance, as the definition of distance is the measurement between one location in space to another. And no absolute time. So, take the basic physics equation d=rt, which can be easily switched around to be rate equals distance over time. But, without absolute distance or absolute time, we have no rate, or speed. With that in mind, why is the speed of light considered a constant, or "special speed" that cannot be passed, if there is no such thing as absolute speed?
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Not a relativity expert, but I can tell you that you've worked yourself around in a circle there.
distance = rate * time is not a relativistic equation. I think it still holds, in general, but the time portion depends on which reference frame you're asking about.
Also, there's no such thing as absolute space, but there is definitely absolute distance in General Relativity. The four-dimensional spacetime distance in a straight line. In fact, when an object is in free-fall near a massive body (or anywhere, actually) it's traveling in a straight line in spacetime.
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the speed of light is real and nothing can go faster than it.
if your going 99% the speed of light time slows for you so much that you observe light traveling at the speed of light compared to you (even though your going 99% of it's speed). Compare this to a stationary observer who will see you and the light zoom by with the light only going slightly faster than you.
I like to think of travel though space time as an x/y graph, one axis is time and one is space, the more you travel though space the less you travel through time and vice versa.
also there is absolute distance. your speed doesn't affect distance as it does time.
massive bump btw idc
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