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| Beamsplitters |
 Title text: Under quantum tax law, photons sent through a beamsplitter don't actually choose which path they took, or incur a tax burden, until their wavefunction collapses when the power is sold. |
Explanation
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This explanation may be incomplete or incorrect: Created by a SOLAR PANEL HIDDEN DEEP IN MEDIAWIKI'S HQ - More on title text and the colapse of wavefunction correlation with to whom and when tax should be paid. Do NOT delete this tag too soon. |
A beamsplitter is a device, usually made from a pair of prisms or a half-silvered mirror, that splits a beam of light into two beams going in different directions. Beamsplitters are used in numerous scientific instruments such as microscopes and (here) telescopes. In a microscope, a beamsplitter may be used to direct the imaging beam to the user's eyes, or to a recording device such as a camera, or to both at once so as to allow visual aiming at specific targets at the same time as conducting scientific measurements upon them. Beam-splitting in order to simultaneously analyse a single 'ray' of light with two or more different types of detectors is also scientifically useful.
In this comic, a beamsplitter is being used in a large-scale telescope to "steal" part of the incident light beam and direct it to a photovoltaic cell. The power generated is then sold on the local grid. The situation may be taken as a darkly humorous implication that surreptitious and legally/ethically questionable strategies are needed to fund scientists and their projects, or it could just be for individualistic gain. The comic pushes the point by supposing that the practice had become so commonplace that the International Astronomical Union (IAU) got wind of it, and has acted to ban the practice.
Most optical instruments, even large telescopes, are unlikely to capture enough light during regular operations to make the "banned" strategy feasible. Moreover, the ban is ham-fisted, as it makes legitimate scientific operation of telescopes profoundly more difficult. For the sake of the joke, both of these issues are ignored.
The telescope shown, without the beam splitter, is a reflecting telescope of the general form of a Gregorian telescope, or a derivative, while the sending of (a fraction of) the light out the side is implemented in the manner of a Nasmyth telescope.
The title text humorously conflates financial tax laws, applicable to the sale of the "stolen" electricity, with the laws of quantum physics, governing the behavior of the photons that are generating the electricity.
Transcript
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This transcript is incomplete. Please help editing it! Thanks. |
- [Cross section of a telescope with some parts of the image darkened to represent the path of light, with portions where the light would be more concentrated being darker]
- [Labels with arrows as they appear left to right, top to bottom:]
- Incoming Light
- Primary Mirror
- Secondary Mirror
- Beamsplitter
- Sensor
- Secret Solar Panel
- Power Sold To Grid
- [Caption below the panel:]
- Astronomy News: The International Astronomical Union has finally banned beamsplitters, optical devices used by scientists to embezzle light from their instruments.
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