Lets take a leap of faith and assume you actually did want to learn something and actually took the time to read something you could do worse than start with this.

http://www.aei.mpg.de/~schutz/download/lectures/AzoresCosmology/Schutz.AzoresLecture1.pdf

You may want to really carefully read the section "Energy and Gravitational Radiation" and that section is not technically hard to understand and explains the problem with energy and gravity waves and directly the problem with your example above and why its all about the tensor metric.

Last edited by Orac; 04/11/15 07:01 PM.
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.