Ok, thank you.
In fact they do not know anything in this field, except dividing by infinite quantities (^^ just kidding), thanks guys for your replies 👍
Thanks Renormalize ;) (it is a good name to speak about QED).
1) Good hint with the specific condition, but very very specific (since we have to use an oscillatory Green function to solve it... but ok with that).
2) Thank you. I read the wiki article on off shell particles, so as I understood...
Thanks Pasmith, I Know. Any function ## f(x \pm c t) ## fits the wave equation ;). But do you have any idea if this kind of solution ## e^{-k(x+ c t)} ## or even (why not) ## e^{- k^2 (x \pm c t)^2} ## can be found in physics (even for mechanical perturbations)? Like for virtual particle ? I am...
Hello everyone. The 1D wave equation is written:
$$ \left( \partial_t^2/c^2 - \partial_x^2 \right) \Psi = 0$$
An electromagnetic wave or matter wave, like free electron (unnormalized here), can be written with the following wave function ##\Psi_m## of energy ## \hbar k c ##:
$$ \Psi_m \propto...
And to go into further details for several species ##i## we have:
$$n^2 = 1 + \sum_i N_i(z) \alpha_i $$
with ##z## altitude, ##\alpha## polarizability, ##N## molecule density, then the surface irradiance become (we can deal also with volumic one):
$$ L = \frac{2 \pi h \nu^3}{c^2}...
Ok guys apologize for the aggressive behavior but I don't like condescending and superiority attitude, just saying, I talked to moderator also to explain.
That being said, I found the solution in wikipedia :bow: (and thks to another forum with this article but the people did not fully...
We don't care an atmosphere layer is isothermal in case of average of day/night and convections phenomena.
Emissivity for a planet ? We have the one of its surface, that's it.
Guys, you know that with heat equation and electromagnetic propagation we can STILL compute in principle the earth...
The thing is I don't accept graphics, I accept equations and definitions.
My question is: How do you define air emissivity ?
Since we are defining emissivity to differenciate how radiates finite surface bodies at the same temperature but different composition, how can I define the emissivity...
No i don't miss the point of integral calculus, I did some vector spherical harmonics analysis during my Phd in light scattering so don't worry about that ;) (by the way this is not what I prefer to do to be honest). You can easily do the computation of absorption of infrared spectra of earth...
Hello guys :)In the frame of finding a physical model for the temperature of Earth's surface, talking about the very "idealized" two-layers model of atmosphere, I ask you now the question to the other physicists or engineers: does it make sens to associate an emissivity to a layer of air (+ some...
Hi Bvu and thank you for the welcome sign and your answer!
You catch the point right... that being said why not in fact? A perfect isolated greenhouse (no air leak), should experience a higher temperature inside because the soil does not radiate out as you just said. This taking the energy of...
Hello everyone, since several weeks, no response from the other forums, I tried to compute a simple model for a greenhouse in a garden. First idea was to compute mass transfer, Navier-Stokes and heat equation all together but in my knowledge no analytical solution exists.I need to build a simple...