Summary: different methods give different results. They are not consistent.
Summary: different methods give different results. They are not consistent.
I use two different methods to detect whether a matrix is singular. The result of calculating the determinant of a 9-order square matrix is...
I am reading GEOMETRY, TOPOLOGY AND PHYSICS written by MIKIO NAKAHARA (second edition). I have a problem on page 400.
I wonder why the sign is minus in Eq. (10.85).
And the same problem appears on page 405 in Eq.(10.108). I think it should be minus one half.
Thank you fzero! Could you please give me some detail? How to get
$$ \partial_i\partial_j \hat{h}^r_{ij} + 2 \partial^4 \epsilon = 2 \partial^2\alpha.$$
from
$$\delta\hat{h}^r_{ii} + 2 \partial^2 \epsilon = 6 \alpha,$$
And how to get the frist line of (A.5). Actually, I do not understand the...
Is there anyone can give me a hand?
http://arxiv.org/abs/astro-ph/0210603
When I read this paper I can not get Eq.(A.5) from (A.4). Why it is ##4\alpha##? If we take the trace of Eq.(A.4), why not it give us ##6\alpha##?
Eq. (A.3):
[Edited by a mentor to fix a small problem in the Latex...
Homework Statement
δ (∂x'^μ/∂x^β)=0
This equation is on my textbook. I don't quite understand. Where x'^μ is coordinate component.
Homework Equations
The Attempt at a Solution
Could you please explain it in detail? Why I run into problems?
What is field strength? In my opinion, it is a parameter to describe a property of the field. The property is belong to the field, it is the nature feature of the field.
dF/dQ is determined by the EM filed itself and has nothing...