Why In 4D, the four-divergence of the four-curl is not zero, for ∂νGμν

  • Thread starter Thread starter physicsgirl07
  • Start date Start date
  • Tags Tags
    4d Zero
physicsgirl07
Messages
2
Reaction score
0
1. prove in the 4-dimensional Riemannian space, the 4-divergence of the 4-curl is not zero that is
where is the 2d’Alembertian operator




2.∂νGμν = ∂μ∂νaν(xκ)−2aμ(xκ) = 0
 
Physics news on Phys.org
So you're asked to prove that in 4D Riemann space (no torsion, connection is symmetric and metric compatible)

\nabla_{\mu}\left(\nabla^{\mu}T^{\nu} -\nabla^{\nu}T^{\mu}\right) \neq 0

Do you know which formulas you need to use ?
 
yes iknow ∇· [∇×a(x)] = ∂i[∇×a(x)]i = i jk∂i∂jak(x)

but i want to prove it in 4-d

becouse in 3-d equal to zero

see this link

http://www.scribd.com/doc/19388495/152/The-curl

see the page that have title curl
becouse i don't know how to wright the formula

thanx
 
Ok, I would choose a free component (let's say in my notation \nu) and make the additions involved. What would you get, if you did the same ?
 
Hello everyone, I’m considering a point charge q that oscillates harmonically about the origin along the z-axis, e.g. $$z_{q}(t)= A\sin(wt)$$ In a strongly simplified / quasi-instantaneous approximation I ignore retardation and take the electric field at the position ##r=(x,y,z)## simply to be the “Coulomb field at the charge’s instantaneous position”: $$E(r,t)=\frac{q}{4\pi\varepsilon_{0}}\frac{r-r_{q}(t)}{||r-r_{q}(t)||^{3}}$$ with $$r_{q}(t)=(0,0,z_{q}(t))$$ (I’m aware this isn’t...
Hi, I had an exam and I completely messed up a problem. Especially one part which was necessary for the rest of the problem. Basically, I have a wormhole metric: $$(ds)^2 = -(dt)^2 + (dr)^2 + (r^2 + b^2)( (d\theta)^2 + sin^2 \theta (d\phi)^2 )$$ Where ##b=1## with an orbit only in the equatorial plane. We also know from the question that the orbit must satisfy this relationship: $$\varepsilon = \frac{1}{2} (\frac{dr}{d\tau})^2 + V_{eff}(r)$$ Ultimately, I was tasked to find the initial...
Back
Top