I Toy problem to motivate the idea of advanced Green's functions

Swamp Thing
Insights Author
Messages
1,035
Reaction score
771
The Wikipedia article on Green's functions says,
the solution provided by the use of the advanced Green's function depends only on the future sources and is acausal. In these problems, it is often the case that the causal solution is the physically important one. The use of advanced and retarded Green's function is especially common for the analysis of solutions of the inhomogeneous electromagnetic wave equation.

What would be a really simple physical toy problem that would motivate and explain the concept of advanced Green's functions?
 
Last edited:

Thread 'A question about variables of integration'

I have the equation ##F^x=m\frac {d}{dt}(\gamma v^x)##, where ##\gamma## is the Lorentz factor, and ##x## is a superscript, not an exponent. In my textbook the solution is given as ##\frac {F^x}{m}t=\frac {v^x}{\sqrt {1-v^{x^2}/c^2}}##. What bothers me is, when I separate the variables I get ##\frac {F^x}{m}dt=d(\gamma v^x)##. Can I simply consider ##d(\gamma v^x)## the variable of integration without any further considerations? Can I simply make the substitution ##\gamma v^x = u## and then...
View full post »

Similar threads

I Green's function for the wave equation
  • · Replies 4 ·
Replies
4
Views
3K
I A somewhat conceptual question about Green's functions
  • · Replies 6 ·
Replies
6
Views
2K
I Confused about Finding the Green Function
  • · Replies 6 ·
Replies
6
Views
2K
Solve second order ode with Green function
  • · Replies 2 ·
Replies
2
Views
2K
I A question about boundary conditions in Green's functions
  • · Replies 1 ·
Replies
1
Views
2K
I Complex representation of wave function
  • · Replies 2 ·
Replies
2
Views
2K
Green's function in electrostatics
  • · Replies 6 ·
Replies
6
Views
3K
I Help me understand convolutions and Green's functions
  • · Replies 10 ·
Replies
10
Views
3K
Greens functions inspection method
  • · Replies 2 ·
Replies
2
Views
3K
A Green function issue: can bound. cond. be applied mode-wise?
  • · Replies 1 ·
Replies
1
Views
1K