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Gravity Probe B

Testing Einstein's Universe

Special & General Relativity Questions and Answers

What is it that physically prevents faster than light speeds?

I have replied to roughly similar answers before, and I guess my answer is still the same. We really do not know why it is that nature has decided that c = 299,792 kilometers/sec or 186,287.9 miles/sec are to be the fastest speeds allowed in our particular 4-d space-time. But experiment after experiment shows that if you take electrons and boost their speeds faster and faster, they behave as though they are gaining mass the faster they are accelerated. In the limit, as you approach the speed of light, the amount of energy required to boost them one millimeter/sec faster outstrips first the energy available in your local power utility, than your nation, and so on. WHY this happens can be very accurately explained by the equations of special relativity, to a zillion decimal places, but as to why it should be so, no one has a clue. This question strikes to the very heart of why our universe seems to be organized around one set of physical laws and constants of nature, and not some other set. Presumably, other possible laws and sets of constants are not so hospitable to our form of life.

Copyright 1997 Dr. Sten Odenwald Return toReturn toSpecial & General Relativity Questions and Answerspage.