# Tag Info

## New answers tagged polarization

3

Polarized, partially polarized, and unpolarized light are a phenomenon of classical optics known for a long time. The first successful theory dates back to 1809, and a complete theoretical description was given by Stokes in 1852, though without reference to the electromagnetic field. The correct way to model classical unpolarized light using electromagnetic ...

0

So my question is, what would electric field of unpolarized EM wave look like when measured (assuming low enough frequencies to be measurable)? To create an unpolarized signal we can start by creating some random noise, allowing it to constructively and destructively interfere with itself. The following is some Mathematica code but written in TeX for ...

3

The following diagram may be helpful: If you have an incident ray that is polarized with the E field up and down (in the plane containing the incident ray and the normal to the surface), then when that ray is refracted, it contains a component of electric field that is perpendicular to the refracted ray (and still in the same plane). The reflection is ...

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The words ultimately refer to the same "objects" but they describe different aspects of them. "Permanent magnets" are objects and they're defined by the external property (what they look like from outside) that the magnetic field remains nonzero around these objects without any activity. On the other hand, "ferromagnets" are materials and the focus is on ...

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I will try to answer this question in two parts: firstly I disagree with the answer in the question you linked. There is "classical unpolarized light" (in some sense) and it is instructive to look at it. Then I will show how this relates to the quantum version. Classical unpolarized light: classically, all the information about the wavefield is contained in ...

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In classical physics, a system can be described by a set of numbers whose values can all be measured using a single instance of that system. In quantum mechanics, a system is characterised by the values of observables where those values are represented by Hermitian matrices. To describe how information is transferred between quantum systems you have to ...

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Fermi transport will be the equations that describe how each polarisation component changes direction, as the ray passes through the gravitational field (or rather, curved spacetime). So for circular polarisation to become eliptical, you need to check whether othogonal components cease to be orthogonal (when Fermi-Walker transported along an arbitrary ...

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Spin is determined from the representation of the Lorentz group the quantum field transforms in. The projective finite-dimensional representations of the Lorentz group are labeled by two half-integers $(s_1,s_2)$. The spin of a field is the sum $s = s_1+s_2$. For example, a scalar transforms in $(0,0)$, a vector field in $(\frac{1}{2},\frac{1}{2})$, a Dirac ...

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When trying to understand light, there are two components to consider: the amplitude, and the polarization, and you can assign both these properties to all points in space. This is very difficult to visualize, so most of these images trying to visualize light are bound to be inaccurate. The first image you show in your post is accurate in showing how the ...

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Any electromagnetic radiation - and in special case light as a small and visible for us part of EM radiation - is composed of photons. This is right for the process of emission as well as for the absorption of EM radiation. Any photon has a electric E and a magnetic B field component, both perpendicular to each other and to the direction of propagation v ...

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Light waves are emitted spherically, however electromagnetic waves nevertheless have polarization. The Maxwell equations that the electromagnetic field satisfies are \begin{array}{rlcrl} \nabla\cdot \vec E ~=& c\rho &~~& \nabla\times \vec E ~=& -\dot {\vec B}\\ \nabla\cdot \vec B ~=& 0 &~~& \nabla\times \vec B ~=& \vec J + ...

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Substantial difference between light and sound is: light is transverse wave and can be polarised; sound wave in gas is longitudal wave and cannot be polarised.

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It all depends on definitions used of course, but overwhelmingly I have found that when people talk about "unpolarized" or "depolarized" they mean a classical mixture of pure quantum states. So they definitely do not mean a superposition state. Another way to understand that a superposition is not "unpolarized", or at least that this is not a good ...

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Let us try to clear up what light means and what a photon means. Light is a solution of classical Maxwell's equations , an electromagnetic wave. As a wave it can have ploarizations that go through filters etc. A photon is an elementary particle which has as energy h*nu, nu the frequency of an electromagnetic wave solution, and is described by a wave ...

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First, you are right about the unpolarized light. Second, whether a photon will be absorbed or not is according to the so-called selection rule which is determined by the conservation law (In this case it is the conservation of angular momentum). Thus you may think that the polaroid is "trying to" absorb each photon. However, the possibility for the ...

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A travelling wave in the direction of the picture(or whatever direction) can have two polarizations, each perpendicular to its direction of propagation. Now, in the black body radiation derivation, we usually use a box as a black body and inside the box standing waves are formed. But standing waves are nothing more(mathematically as well as physically) ...

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On the face of it, the answer is "nothing will happen". However, if you bring the surfaces close enough together, you may find that electron affinity between the two is different, in which case electrons may move by a very small amount - in the same way that when atoms react, the resulting molecule may have a dipole moment. The effect would be restricted to ...

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As others have noted, the stereopsis cues to depth would indicate that objects appearing on the same point on the screen for both eyes would be perceived as being at the screen. While points being farther appart in the direction of the eye(left eye image moved further to the left, right eye image further to the right) appear to be further away than the ...

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The others have already provided good explanations, but since it sounded like an interesting question and I already sketched up a diagram, I thought I would show it, too. As already mentioned, if you have an object that is to be shown as the exact same distance as the distance between you and the screen, it's very easy to represent that: It's just a single ...

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If the text appeared to be at about the position/distance of the actual screen in the theater and if the stars appeared to be much further behind the screen, then what you observed with the glasses off was exactly correct. To focus on the screen, which is not at "infinity", your eyes have to cross slightly. In that case, the stars that are intended to be ...

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That's a very good observation! The screen is at a finite distance. If you want to show something at the distance of the screen, then, obviously (?) the two images would be in the exact same location on the plane of the screen. That's the text. Now imagine something way, way behind the screen (stars are at infinity). Draw an imaginary line from each star to ...

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