Tagged Questions
1
vote
1answer
88 views
Killing vector argument gone awry?
What has gone wrong with this argument?!
The original question
A space-time such that $$ds^2=-dt^2+t^2dx^2$$
has Killing vectors $(0,1),(-\exp(x),\frac{\exp(x)}{t}), ...
0
votes
1answer
76 views
Spacetime and Timelike Intervals
The difference between a “timelike” spacetime interval and a “spacelike” spacetime interval can be understood in the following way: If the spacetime interval between two events is timelike, there ...
0
votes
1answer
55 views
How much energy is needed to curve the space so the Sun will come 1 meter closer to our planet? [closed]
How much energy/work will it take if our planet is:
5.9736×1024 kg
or
3.0×10−6 Suns
to move Sun and Earth 1 meter closer ...
0
votes
0answers
85 views
Sequence of events in special relativity [closed]
I am taking a general education course on special relativity, and get quite confused by problems asking about which event happens first according to different observers. Is there an effective way to ...
1
vote
1answer
218 views
What is the general relativistic calculation of travel time to Proxima Centauri?
It has already been asked here how fast a probe would have to travel to reach Alpha Centauri within 60 years. NASA has done some research into a probe that would take 100 years to make the trip. But ...