# Tag Info

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As mentioned by Ruslan , precisely speaking, what one should do to simulate the unpolarized light is to take an average of the intensity of all the orthogonal polarized light other than just 2 of them. Plane source is a special case because its z-polarized component is quite weak so it won't hurt even if only an average of x and y-polarized component is ...

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linearly - then there's exactly the same number of both spins. This is incorrect. If you have a collection of photons in which half are left hand circularly polarized ($L$) and half are right ($R$), then you have unpolarized light (not linearly polarized). If you have linear polarized light, then each photon is in a (quantum) superposition of R and L at ...

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electromagnetism is not a handed force. So i don't think you even need to use vectors that are transverse. I recently, learned about a mathematical object called a differential form. a dx+dy is like the k unit vector and dx-dy is like -k. So spin can be described in a more natural way that does not resort to a perpendicular direction. Definetly, more than ...

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light rays are not one dimensional objects. True, in the figures that directed segments are shown. Mathematically, you can think of sort of an infinitesimal vector showing that direction. it can be made infinitely small. is that 0 dimensional small, i don't know. I don't think it is. It would have the dimension of dx.

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You are right that the oscillations of the electromagnetic field need not have any spatial extent. The oscillations, as you point out, are in the strength of the electric and magnetic fields. If I understand your question correctly, you are asking why then can some objects distinguish between the two different polarizations of light. This is because ...

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If instead of the string Light were to be used then it will pass through both of the slits S1 and S2. The book is using this analogy to explain the concept of polaroids. The whole string-slit system that your book quotes is analogus to the above shown light-polaroid system. Light will not pass through the second polaroid. I am not explaining how polaroid ...

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Just to add to Anna v's answer and Aanel's answer which are both admirably pithy and correct. Polarisers making use of the Brewster angle deflect the light of the "blocked" polarisation, rather than absorbing it. The "blocked" light actually passes into a refracting, the unblocked light is reflected off and redirected to the output. Polarising beamsplitters ...

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Light that is not transmitted is either absorbed or reflected. Wire grid polarizers tend to reflect. Polarization beam splitters separate the two polarizations in different directions. Polymer based ones absorb it i believe...

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In general light that does not pass a barrier, a wall for example, is absorbed.The energy is turned mainly into heat and also chemical bond breaking etc. The part of the light beam that does not have the correct polarization for the polaroid will be absorbed in the same way.

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As Ruslan said, your error lies in the fact that you used z-polarized light. There is no such thing as z-polarized light (it doesn't exist).

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Assuming 3D RealD glasses - uses circular polarized light to cancel images. To understand better, ask yourself why do I see my eyes when both eyes are opened? The answer is that your brain mixes two reflected images: one image contains your left lens blacked the other image contains the right lens blacked When you close an eye, you cancel one image. ...

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The axes definitely matter. If you put light through a linearly polarized glass pane, the output light will be entirely polarized along the polarization axis of that pane. The intensity of the output light will be $$I_{\textrm{out}} = I_{\textrm{in}}\cos(\theta)^2$$ where $\theta$ is the angle between the polarizations of the ingoing light and the pane, ...

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Alan Guth summed it up nicely (emphasis mine): Measuring the amplitude, or strength, of the primordial B modes at different angular scales tells you how the inflationary expansion rate changed with time during the period of inflation. Understanding the extent to which it varies is an important clue to determining details of what drove the inflation. ...

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It's the same $\ell$ that indexes the spherical harmonics $Y_{\ell m}$ (or $Y_\ell^m$ if you prefer). We can decompose functions defined on the sphere (like anything defined on the sky) into a countably infinite sum of appropriately weighted spherical harmonics. $\ell$ counts the number of nodes, while different values of $m$, \$0 \leq \lvert m \rvert \leq ...

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Perhaps this defintion? The electric (E) and magnetic (B) modes are distinguished by their behavior under a parity transformation n → -n. E modes have (-1)l parity and B modes have (-1)l+1, here (l=2, m=0), even and odd respectively. The local distinction between the two is that the polarization direction is aligned with the principal axes of the ...

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The confusion probably comes from the fact that E-fields and E-modes are entirely different (but are etymologically similar). A photon carries an intrinsic polarization. In classical E&M, we think of a single light wave as an oscillation of electric and magnetic fields. In vacuum, things are nice and simple, and the propagation direction, the electric ...

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Generally in Nd:YAG harmonic generation using KTP, Type-II collinear phase-matching is used, which means that both ordinary and extraordinary polarizations are mixed to form an extraordinary polarized doubled beam. In essence, both polarizations of light in the unpolarized beam are combined to form a polarized beam. This means that while unpolarized light ...

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