一个中年男人口述：患上抑郁症我把初恋女友看成魔鬼
百度 （黄建忠）(责编：刘天宇（实习生）、张雨)
Propagating solutions to Maxwell’s equations in classical electromagnetism and real photons in quantum electrodynamics. A superset of thermal-radiation.
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How does a self-sustaining electromagnetic wave originate from an oscillating charge?
I'm a beginner trying to understand electromagnetic waves conceptually, without heavy mathematics.
I recently watched an animation where an oscillating charge produces an oscillating electric field ...
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Dispersion: Denser to rarer medium
We have studied dispersion of a ray of white light when it goes from denser to rare medium (from air to glass). But when the ray of light comes out on the other side, do the various light rays get ...
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Why do we name and separate invisible bands even though the whole EM spectrum is continuous?
I know that the electromagnetic spectrum is fundamentally continuous—ranging from radio waves and microwaves, through infrared, visible light, ultraviolet, X?rays, to gamma rays—without sharp ...
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Can a few photons travel in a medium faster than the classical limit?
The best explanation for light having slower speed in a medium involves the electrons in the medium oscillating in the optical field and the re-emitted radiation having slight phase (time) delay
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Do window screens block WiFi? [closed]
I'm thinking of putting a wifi satellite on a screened in porch outside, to cover my yard. The Internet seems to think that wire screens don't block wifi, but wifi has a wavelength of 2 inches or more,...
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Why doesn't Ampere's Law violate Special Relativity?
Ampere's Law states $$ \oint \vec{B}\cdot \ \vec{d\ell} = \mu_o \left( I + \epsilon_0 \frac {\partial \Phi_E}{\partial t} \right).$$
Special Relativity states that no event can be detected outside of ...
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How much faster does quartz glass cool via radiation compared to opaque substances?
Throw a piece of quartz glass (or any other transparent object with a high melting point) into space and uniformly heat it up to a certain temperature, say 1500 K. At this temperature, quartz glass is ...
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Can we derive laws of reflection by treating reflection as a form of wave scattering theory?
My professor once told me that reflection of light is fundamentally a form of the scattering of (electromagnetic) waves. When I asked him to explain it a bit his response was the following. When light ...
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Mechanism of Energy Conservation if Two Phase-Offset Photons Sum to Zero-Amplitude [closed]
EDIT: I somehow didn’t notice a cross product sign error, that’s the actual answer to my question. If the two wavefronts have opposing propagation direction and electric field vectors at the time of “...
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What is my geiger counter picking up from this neon discharge lamp?
This is just a mini tesla coil exciting an Eisco neon discharge lamp. The detector is a MightyOhm geiger ++ which detects beta and gamma radiation. I'm recording 30-60 CPM just with background ...
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Is there a graph of various attenuation processes across all energy regimes for any material?
I have been trying to find the absorption cross-section of extreme ultraviolet radiation for various atmospheric molecules, but most papers and graphs I've seen don't map that region, almost always ...
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Are there are general bounds on how the radiated powers for two source configurations can combine?
Suppose you have some electric source configuration $(\rho_1({\bf x}, t), {\bf J}_1({\bf x}, t))$ (satisfying the continuity equation) that produces a total (time-averaged and angle-summed) radiated ...
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Transversality of electromagnetic waves
What is the simpliest way to prove the transversality of electromagnetic waves propagating in vacuum in absence of sources?
I can easily find the proof for the transversality of electromagnetic plane ...
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Can a uniformly accelerating charge radiate in all reference frames?
In an inertial frame, an accelerating charge emits radiation. But what happens in a co-accelerating frame? Does radiation still exist, or is it frame-dependent? And what does this imply about energy ...
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What actually oscillates in quantum entities and the wavefunction associated to them ? (grade 12) [duplicate]
I am in class 12 and studied bit of quantum mechanics and have few doubts:
For particles what is actually oscillating or waving?
I have known that wavefunction associated to them oscillates but in ...
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