Propagating solutions to Maxwell’s equations in classical electromagnetism and real photons in quantum electrodynamics. A superset of thermal-radiation.

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### Polarization of electric field and its effect on the Poynting vector

To preface, I've little experience with optics. This is a very use-case specific project I'm undertaking. So, if there are any improvements in my method, I'd appreciate it! I'm working with the vector ...
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### How does an electromagnetic wave behave when it enters a medium with refractive index less than unity?

From what I am able to find, the phase velosity of the wave exceeds c, but the group velosity remains less than c. However, why does the wave form wavepackets after entering a medium with refractive ...
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### Can light propagate in the absence of electric and magnetic fields?

It has been established that light or other forms of electromagnetic radiation needs electric and magnetic fields in order to propagate. What would happen if it were possible to shield an area from ...
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### Physics behind Lambertian reflectors

Most ordinary surfaces are near Lambertian diffuse reflector, i.e. a small local radiates most strongly at norm then attenuates by cosine law when one gets to the tangentials. However this seems hard ...
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### "Residence time" of a photon?

E.g. CO2 absorbs and emits electromagnetic radiation at some frequencies. If the CO2 molecule is in a continuous electromagentic field, it will absorb and emit. What is the time between absorption and ...
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### How did Fermi arrive at this particular expression of canonical conjugate?

Fermi (Quantum Theory of Radiation 1932), using the electromagnetic energy expression $W_e$, a new variable $v_s$ is derived in equation: $$v_s=\frac{\partial W_e}{\partial \dot{u}_s}$$ which is ...
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### How exactly classical electrodynamics fails to explain the Compton effect?

EDIT: This is a more precise version of an old post Classical Theory explanation of Compton Effect by someone else. Standard textbooks explain the Compton effect using the notion of photon. It is ...
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### Understanding radiation mechanism of inset fed microstrip antenna

I have designed a simple inset-fed microstrip antenna, resonating at 2.45 GHz. The transmission line model of the antenna reduces it to two radiating slots separated by a microstrip line, and it's ...
1 vote
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### Why do light bulbs don't produce coherent waves? [duplicate]

My textbook says that light ways produced by light bulbs are not coherent but it doesn't describe the reason. I was wondering how could two waves not be coherent regardless of the source they are ...
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### Does gravitational lensing bend light of all wavelengths by the same amount?

Basically I am asking if gravitional lensing is bending or refracting light.
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### Why does white light appear white?

When I think of white light, I'm imagining a combination of all 7 colors of light but I believe that since light has wave nature I can say that at some point that the probability density of red light ...
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### On a tinted (reflective) window, why do I need to look from up close to see inside?

I've noticed that on a really tinted window, when looking from farther (and even pretty close just not touching the window), you cannot look inside, but when you put your head so close to the window, ...
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### Effective aperture as a function of Azimuth and Elevation Angle

Wikipedia says The effective aperture of an antenna is given by $$A_{\mathrm{e}}(\theta, \phi)=\eta A \cos \theta \cos \phi ,$$ where, $(\theta, \phi)$ are the azimuth and elevation angles relative to ...
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### Mach Zehnder Do-it-yourself

I have a red laser and BS. Can I make MZI at the lab? I heard that is very difficult to achieve the calibration. What is expected to be seen after BS2? A dark spot at centre with fringes around? I ...
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### Emission of a single photon

When a single photon is emitted as a result of an electronic transition, it will have a defined energy and wavelength. However, its amplitude is not constant over infinite space and time; instead, it ...
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### Paradox in the observation of ripple

What I am going to speak about may not be a paradox but i see a contradiction here so I used used the word "paradox". To begin with, let there be 2 charges A and B which are stationary with ...
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### Track an object velocity in a 2D plane

I would like to track the motion (actually, I am more interested in the velocity) of an object in a 2D plane (typically 4m x 4m). The object speed is typically 10cm/s, but the mouvement may be chaotic ...
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### Why aren‘t other metals colored?

From an online lecture, I heard that $d$ orbitals cause metals to have a peak in their reflectivity curve at some wavelength. This is generally the case for most metals. However, the peak lies mostly ...
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### The speed of light in medium with different frequency

We know that the speed of light in vaccuum can be expressed as $c=\frac{1}{\sqrt{\mu_0\epsilon_0}}$ and thus the speed of light in vaccuum is thus v=\frac{1}{\sqrt{\mu\epsilon}}=\frac{c}{\sqrt{\...
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### Does infrared radiation emitted by an object happen only from its surface, or is emission also from the centre of the object?

Textbook answer of how radiation is emitted is from the surface. Does the inside of a object also emit infrared?
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### Can an electromagnetic wave be polarised in the direction it propagates?

Can the electric field vector of an EM wave oscillate in the propagation direction? In text books the polarisation is always orthogonal to the propagation direction. I'm wondering specifically ...
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### Is heat basically infrared?

Particularly given the fact that heat can propagate through a vacuum in the form of infrared radiation. But is the modern theory of heat based on the notion that heat in the matter(regardless of its ...
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### How big is light pressure as a fraction of light energy?

Light hitting a surface impart a force on the surface, often called "radiation pressure". My question is, given a perfectly reflective surface, if light hits it at 90° to return in the ...
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### Huygens Light Theory using Spheres and Miller's recent discovery?

Huygens writes in "Treatise on Light" a theory that propagation of light through the aether can be explained using Spherical waves emanating from every point and they interfere. Miller ...
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### Solving Maxwell Equations when a charge is put inside a generic conductor

A net point-charge density $\rho_0$ is impressed without speed (no impressed current density) at position r0 at time $t_0$. Relaxation analysis tells us the charge density will decrease exponentially ...
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### What is the difference between photons and electromagnetic waves?

Electromagnetic waves are generated by accelerating electric charges. Photons on the other hand, tend to describe something different, specifically the particle nature of electromagnetic waves as ...
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### What is the significance of "oscillating" electromagnetic waves as compared to other disturbances?

When we speak of electromagnetic waves, we think of oscillating waves. But all disturbances need not be oscillating at a frequency. For example, if I take water, I could just lower the bottom plate ...
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### What is the origin of energy emitted as radiation by an electrically charged object stationary around a massive object?

Einstein's special relativity tells us that laws of physics are the same in all intertial frames. General relativity futher extends this by stating that reference frames that are in free fall around ...
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