Sort:  

I didn't know about Stephen Hawking mentioning this. But the exercise is very common in special relativity books. I have by far not invented it ;)

hehe sounds interesting. I would like to learn it too :D

The only reference I have is a book in French. I cannot find anything on the web. I may write a post on it next week, if you want. That is a funny topic :)

Coin Marketplace

STEEM 0.18
TRX 0.13
JST 0.028
BTC 64911.06
ETH 3194.94
USDT 1.00
SBD 2.60