Frequently asked questions. Whenever the same question winds up getting asked over and over again, this tag should designate the _original_ one, which we close all the others as duplicates of.
71
votes
1answer
5k views
Book recommendations [closed]
Every once in a while, we get a question asking for a book or other educational reference on a particular topic at a particular level. This is a meta-question that collects all those links together. ...
20
votes
12answers
2k views
Is it possible for information to be transmitted faster than light by using a rigid pole?
Is it possible for information (like 1 and 0s) to be transmitted faster than light?
For instance, take a rigid pole of several AU in length. Now say you have a person on each end, and one of them ...
5
votes
6answers
2k views
Is time travel possible? Is it possible to go back in time?
I read somewhere that according to relativity, black holes and other space related stuff it is possible to jump into past.
Is it possible for anything to go back in time either continuously or by ...
2
votes
2answers
1k views
Balloons and lifting gases
Hydrogen is the lightest element, so it's cable of lifting the most weight in out atmosphere (probably not the best terminology there, but you get the picture)
Would hot hydrogen (in the same sense ...
-7
votes
7answers
2k views
Does Quantum Physics really suggests this universe as a computer simulation? [closed]
I was reading about interesting article here which suggests that our universe is a big computer simulation and the proof of it is a Quantum Physics.
I know quantum physics tries to provide some ...
21
votes
4answers
980 views
Why does the sky change color?
Why the sky is blue during the day, red during sunrise/set and black during the night?
