Green's function can be utilized to calculate the charge density of states, as indicated by Nieminen's work in Phys. Rev. B. The relationship is expressed as rho = -1/pi Im(G°) and delta rho = -2/pi I am (int (delta G dE)). These equations suggest a method for deriving the density of states using Green's functions. The discussion highlights the need for clearer examples and derivations to understand this application better. Overall, Green's functions serve as a critical tool in theoretical physics for analyzing charge densities.
#1
Tanja
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Does anybody know how Green's function can be used to calculate the charge density of state?
Thanks
Tanja
In Phys. Rev. B, 66, 165421 (2002) by Nieminen
they state that rho = - 1/pi Im(G°), without explanation and in
Phys. Rev. B 60, Number 4 (1999) also by Nieminen:
delta rho = -2/pi I am (int (delta G dE))
There must be a way to derive the density of state by Green's functions.
Imagine a charged sphere at the origin connected through an open switch to a vertical grounded wire.
We wish to find an expression for the horizontal component of the electric field at a distance ##\mathbf{r}## from the sphere as it discharges.
By using the Lorenz gauge condition:
$$\nabla \cdot \mathbf{A} + \frac{1}{c^2}\frac{\partial \phi}{\partial t}=0\tag{1}$$
we find the following retarded solutions to the Maxwell equations
If we assume that...
Maxwell’s equations imply the following wave equation for the electric field
$$\nabla^2\mathbf{E}-\frac{1}{c^2}\frac{\partial^2\mathbf{E}}{\partial t^2}
= \frac{1}{\varepsilon_0}\nabla\rho+\mu_0\frac{\partial\mathbf J}{\partial t}.\tag{1}$$
I wonder if eqn.##(1)## can be split into the following transverse part
$$\nabla^2\mathbf{E}_T-\frac{1}{c^2}\frac{\partial^2\mathbf{E}_T}{\partial t^2}
= \mu_0\frac{\partial\mathbf{J}_T}{\partial t}\tag{2}$$
and longitudinal part...
Is it true that in any mechanical set-up, it is possible to predict the nature of Normal Reaction ( magnitude, direction, etc. ) without solving through the dynamical equations of motion and constraints for the set-up as Normal Reaction is completely unknown? I mean is it true that we can explain NR intuitively beforehand?