Polarization characterizes the oscillations in time the electromagnetic field is doing in the plane perpendicular to the propagation direction of a wave

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Difference in perception of unpolarized and polarized light

What is the difference in perception of polarized light and unpolarized light? What difference does polarized light cause to our eyes?
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306 views

How many photons does it take to measure a linear polarization?

A star emits perfectly (100%) linearly polarized light at an arbitrary angle. How many photons must you detect to measure this angle to a precision of n binary digits? (with greater than 50% ...
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152 views

Polarization of Light

How do materials polarize light? I know that they polarize light in the same plane, but light has two perpendicular directions with the two fields, so which direction is reflected and why? And if ...
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548 views

Electromagnetic field of unpolarized light

I need help in finding an expression for the instantaneous electric and magnetic field of unpolarized light in order to write down and evaluate the time-averaged norm of the Poynting vector (i.e. the ...
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409 views

Why photon only have helicity other than spin? [duplicate]

When learning angular momentum in quantum mechanics, a spin 1 particle have 3 states. Then I saw from sakurai's modern quantum mechanics that photon's two polarization are just like spins, but with ...
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Three polarizers, 45° apart

If light is passed through two polarizing filters before arriving at a target, and both of the filters are oriented at 90° to each other, then no light will be received at the target. If a third ...
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145 views

Are gravitational waves transverse or longitudinal waves, or do they have unique/unknown properties? [duplicate]

Gravitational waves propagate through a medium of space-time. Are they traverse waves or longitudinal waves? Or do they propagate without oscillating?
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90 views

Spatial and polarizing beam splitters in a graphical calculus

Suppose I have four wires, and I tensor product them together $A \otimes B \otimes C \otimes D$ I pass $A \otimes B$ through a spatial beam splitter $Spl: A \otimes B \rightarrow A^\prime \otimes ...
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581 views

Polarization rotation: Jones Matrix that maps Horizontal to right circular

I am looking at the Poincaré sphere and I am trying to compute a Jones matrix for a particular rotation. Specifically, I would like it to perform the following maps: $O :|H \rangle \rightarrow |R ...
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180 views

Reflected optical rotation of polarised light

Assume polarised light travels through an optically active medium (e.g. water with lots of sugar) with the specific angle $\alpha_s$ of depth $d$ at which end it is reflected (so in total it travels ...
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101 views

What causes these rainbow effects using a polarizing filter on an airplane?

I know that light reflected from a surface at 45° is polarized and that for a similar reason skylight arriving from a direction orthogonal to the sun is polarized too. Photographers make use of this ...
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462 views

light linear polarization and photon spin

After reading about light polarization I understood, that if light is polarized: circularly left then the spin of each photon is parallel to the velocity circularly right then the spin of each ...
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177 views

Polarization vectors in scattering amplitudes

The annihilation ($e^+ e^-\rightarrow 2\gamma$) diagrams are I'm just wondering if the amplitudes should be $$(-ie)^2\left[\bar v(p_2)\gamma^b\epsilon_b^*\frac{-i(-(\gamma^\mu p_{1\mu}-\gamma^\nu ...
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640 views

Monochromatic wave

If we have an EM wave like this one: $$E=\begin{pmatrix}1\\i\\0\end{pmatrix}e^{-i(\omega t-kz)}$$ The wave has clearly only one frequency $\omega$, but is it monochromatic? My doubt is that it's ...
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248 views

Filter out polarized light

Unpolarized light enters the polarizer and gets polarized at one certain angle. If we place an analyzer behind the polarizer and align them, we observe that all light is transmitted. If we rotate the ...
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59 views

Charge in a layered ball

A ball (radius $R$) has three layers. For $0<r<a$ it is a conductor with free charge $+Q$. For $a<r<b$ it is a linear dielectric $\epsilon$ with free charge embedded in it with density ...
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307 views

double slit experiment with two opposite quarter waveplates

Consider the usual double slit experiment involving laser and a double slit and a screen. Now place in front of the left slit a quarter waveplate (let's call it QWP1) that changes a certain linear ...
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3D glasses and reflection/polarisation [duplicate]

Hi all, Tonight I'm going to see a 3D film so I thought I'd check whether I had any old 3D glasses around the house. Found a pair of "RealD" glasses. Anyhow, I assume that the glasses use some ...
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How does one calculate the quantum propagator for a massless photon

So I want to calculate the quantum massless photon propagator. To do this, I write $$ A_\mu(x) = \sum\limits_{i=1}^2 \int \frac{d^3p}{(2\pi)^3} \frac{1}{\sqrt{2\omega_p}} \left( \epsilon_\mu^i (p) ...
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Polarization of sound

Sound can't be polarized because the vibration of such type can't be polarized i.e, it can't be limited or controlled by any barriers and so polarization is not possible in them. This is what my ...
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When polarized light hits a polarizer, what happens to the polarization which is not transmitted?

It is typically said that in polarization of light only those waves can pass through a polaroid which has a plane of vibration parallel to the axis of polaroid. My question is: what happens to the ...
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129 views

How come these 3d glasses don't show a difference between horizontal and vertical?

I thought that modern 3d glasses work by having one lens filter horizontally polarized light, and the other filter vertically polarized light. However, I found this pair of 3d glasses at my parents' ...
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Counting degrees of freedom of gauge bosons

Gauge bosons are represented by $A_{\mu}$, where $\mu = 0,1,2,3$. So in general there are 4 degrees of freedom. But in reality, a photon (gauge boson) has two degrees of freedom (two polarization ...
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85 views

Can polarization effect the coherence length?

I'm taking an optics lab in which I'm required to construct an interferometer, and measure the wavelength of a laser, and the coherence length of the light emitted from a candle fire. Now, I've been ...
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439 views

How does the Ocean polarize light?

I know that the light gets polarized in the plane of the ocean, but why is that? It seems to me that the molecules are free to be in any position or location, so why is it that the 'vertical' ...
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417 views

Doubts concerning Wigner's classification

Wigner classified particles in function of the eigenvalues of $P_\mu P^\mu$ and $W_\mu W^\mu$. Then, it can be proved that for massless particles spin values can be only $\pm s_{max}$. But for a ...
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689 views

Why do polarized sunglasses remove (most) reflections on car windows?

Why do polarized sunglasses remove (most) reflections on car windows? I know that both lenses of polarized sunglasses are polarized in the same direction and I can see that reflections in my own ...
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What are the polarization states of the photons in a polarized and unpolarized light?

The photons are completely polarized, i.e their polarization states can be expressed as $a|R\rangle+b|L\rangle$, where $|R\rangle$ and $|L\rangle$ are two helicity eigenstates of the photon. For ...
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What is the effect of polarization on diffraction by a narrow slit?

Consider the well known demonstration of diffraction by a narrowing slit. (See for example the demonstration at the 30 minute mark of this lecture at MIT by Walter Lewin) It is my (possibly mistaken) ...
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118 views

How to count the number of modes/polarizations of a Gaussian field theory?

A Gaussian (free) field theory is described by a quadratic action of the field, e.g. $S=\int\psi^\dagger K\psi$ (or $S=\frac{1}{2}\int\phi^\intercal K\phi$ for real fields). Usually one just need to ...
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219 views

Why is there sometimes an additional term in the orthogonality relations for the polarization vectors?

When considering the polarization vectors of a massive spin-1 field, like an $A_\mu$ with Lagrangian density $$ \tag{A} \mathscr{L} = - \frac{1}{4}F_{\mu\nu}F^{\mu\nu} + \frac{1}{2}M^2 A_\mu A^\mu,$$ ...
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128 views

Polarisation of light is a wave concept or applicable to photons as well?

I have a very fundamental question. We explain polarisation of light assuming wave nature of light. Is it still valid if we assume light as photons? Or in other words, polarisation is a wave concept ...
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89 views

Can unpolarized light be created from polarized light?

I have a question regarding this topic. According Stokes Parameters theory, unpolarized light could be described as a superposition of two independent beams of equal intensity and orthogonal ...
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155 views

How does one calculate the polarization state of random light after total internal reflection

How does one calculate the polarization state of random light after having been totally reflected by a single dielectric interface? Please consider pure specular reflexions from a plane interface ...
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410 views

electric field of unpolarized light after reflect?

Reflection and transmission (Fresnel equation) of polarized light are treated in many optics or electromagnetism books. If $E_s$ and $E_p$ is incident electric field with s-polarization and ...
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192 views

How can a Jones vector give linear polarization along an axis?

If we represent a Jones vector by two complex-valued exponentials, $J_1 = e^{i \phi_1}$ and $J_2 = e^{i \phi_2}$, how can this ever give a polarization along the x-axis? We write such a polarization ...
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383 views

What is a photon's speed inside a dieletric?

We know that EM waves are slowed down in a dielectric. But at what speed does the photons that make up the wave travel? Do they always travel at the speed $c$, but colliding/being absorbed and ...
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505 views

Is there a simple model explaining Faraday effect?

I find magneto-optical effects fascinating, and especially the Faraday effect. But most sources only give a phenomenological description, while I want a deeper explanation of its mechanism. Is there a ...
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264 views

Intrigued about a polarizer effect

This comes from one of my physics course at university (many years ago!), I hope I recall it right. We were studying optics, and were given some polarizer filters to experiment. They were disc- ...
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Optics - Faraday Rotator using waveplates

I'm trying to replicate the effect of a 45° Faraday rotator using a series of waveplates instead. I've encountered some difficulties using the jones matrix notation, the main book I'm using is: ...
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About partially polarized light and the degree of polariztion

When I was taking Optics course, I found there were several questions about polarization of light. I use the textbook of Hecht. It seems that the definition of degree of polarization may be not so ...
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235 views

How would one generate Brownian light? What would it look like?

When light is an equal mix of all visible frequencies, we call it white light. By analogy, sound that is a mix of all audible frequencies is called white noise. For sound, there is an additional ...
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Decoherence of a Coherent Beam

If retarding films (i.e. wave plates) can retard the electric components of light (based on the films thickness) without affecting it's direction, couldn't I use a retarding film of randomly varying ...
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30 views

Polarisation by Reflection - oscillation direction

I'm currently studying polarisation by reflection, and have come across two pieces of information from the same source, which I can't seem to understand on how they differ. The oscillation direction ...
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114 views

Polarization in Lasers and Liquid Crystal Displays

When we talk about Polarization in Lasers we mean placement of the crystal at Brewster angle to block the s-polarization and only the p-polarization will survive. How do we compare the term ...
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3D movie optics mathematics

I get the idea that we use two polarized light sources and a parallax rendered film such that the objects seem to resemble true parallax in our eyes once it passes through the polarized glasses, but ...
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113 views

What is fundamentally happening that causes light to change its orientation when repeatedly polarized? (edited)

When light is passed through two polarizers successively, its intensity and orientation afterwards depends on the angle between the polarizers and the orientation of the most recent polarizer, ...
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51 views

What sort of polarisation causes this effect

By some chance I acquired a pair of specialized '3d' glasses to be used in conjunction with a poster, such that when viewing the poster (which was a map of australia) the contours popped in and out of ...
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Detecting Polarization States of Quantum Field

(Background) In the scenario where a gauge symmetry is spontaneously broken and the gauge field eats the Goldstone boson to acquire a mass, the massive gauge field acquires a longitudinal ...
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Superposition principle and polarization

I am reading an optics book (Physics of Light and Optics by Peatross and Ware) that asserts this: A beam of light can always be considered as an intensity sum of completely unpolarized light and ...