Difference between revisions of "Talk:2817: Electron Holes"

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(p-type semiconductor physics joke)
(Who is firing the beam?)
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A contributor wrote, "Here, the electron hole gun might refer to the anode ray tubes." An anode ray is a beam of positive ions; these are actual particles and not "quasiparticles", and therefore the comic does not refer to them. [[Special:Contributions/162.158.86.243|162.158.86.243]] 07:05, 20 August 2023 (UTC)
 
A contributor wrote, "Here, the electron hole gun might refer to the anode ray tubes." An anode ray is a beam of positive ions; these are actual particles and not "quasiparticles", and therefore the comic does not refer to them. [[Special:Contributions/162.158.86.243|162.158.86.243]] 07:05, 20 August 2023 (UTC)
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== Who is firing the beam? ==
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Are we so sure it's Beret Guy? Depending on how dangerous or destructive it is, it could be Black Hat? And is using the first person in the title text ("my") for a character like Beret Guy, instead of for a fictionalized Randall Monroe with weird hobbies, a departure from usual norms?

Revision as of 20:49, 20 August 2023


I must admit... I'm not entirely convinced that one _couldn't_ build an electron hole beam. It would probably be called a quasibeam, but I think it could be done. 162.158.175.61 05:11, 19 August 2023 (UTC)

Would an electron "vacuum" be an electron hole gun? Barmar (talk) 05:30, 19 August 2023 (UTC)

Is it worth mentioning that "pewpewpew" was one of the incorrect pronunciations of Perseids in 2814? Barmar (talk) 05:34, 19 August 2023 (UTC)

Foreshadowing! Note it there? 162.158.86.182 08:11, 19 August 2023 (UTC)

Objection, Your Honor! Don't know if electron quasibeams (see comment above) can be done, but the "a beam consisting of a lack of something is not possible" in the current explanation is too wide. Think of antisound devices! I think a "vacuum beam" going through normal gas pressure is very possible. And what about the Meissner effect, which could be seen as a beam of absence of a magnetic field? 198.41.242.211 07:25, 19 August 2023 (UTC)

Anti-sound just exactly(/sufficiently) compliments the sound you're trying to 'remove'. On its own, it is sound in its own right.
Projecting a vacuum (which would, incidentally, quash sound except for that which travels round it or is caused by its creation/collapse) sounds like it needs a whole army of Maxwell's demons carrying their own 'portable hatches' to allow air molecules to leave the volume of the beam whilst batting away any that threaten to move into it. (That might be interesting to see, if noisy.)
The Meissner Effect is an interesting (practical) version of this. Upon decreasing the possibility of an interior field, an identical increase is detetected immediately outside of it (conserving flux across the whole system, or so it seems to be/makes most sense).
Which is not to say that there's no such thing as "a nothing", in the whole weird world of science, or variously vagues analogues to it (if you don't dig too deep, maybe). Some might suggest quantum vacuum decay might be the ultimate substantial 'nothing', but not that we know how to study it... let alone harness it. Yet! 172.71.242.5 10:23, 19 August 2023 (UTC)
Those aren't "beams of nothing" but rather "beams of things that cause another thing to be suppressed/expelled/cancelled" 172.69.247.43 14:49, 20 August 2023 (UTC)

When the positron was first predicted it was modeled as an electron hole, a gap in the hypothetical "sea" of negative-energy electrons filling all space. Sadly, AFAIK modern quantum field theory has done away with that idea, so while a gun that shoots a positron beam is theoretically possible, it probably wouldn't qualify as an electron hole beam. Hmj (talk) 08:03, 19 August 2023 (UTC)

I (separately) mentioned positrons in an edit summary just now. Of course, adding the two concepts together makes for an even more ridiculous thing... A 'positron hole beam'. You know all those positrons we (don't, in general terms) have floating around us? This now projects a concentrated lack of them! 172.71.242.5 10:23, 19 August 2023 (UTC)

I firmly believe the printer deserved it. It knows what it did. 162.158.19.95

Electrical current was defined as the flow of positive charge carriers before it was understood that the negative charge carriers (electrons) were what was moving. When talking about semiconductor physics, this became a problem because we’re very concerned about what particles are actually moving around, so the mathematical fiction of “hole flow” was invented so we wouldn’t have to use negative signs everywhere in the math. An electron hole is a property of p-type semiconductors, a place where electrons can move into, which can also be described as the nonsensical but more mathematically convenient flow of holes in the opposite direction. By analogy, if you had a children’s shape-sorting box, you could build a catapult that threw around the blocks, but you couldn’t build something that threw around the holes in the lid that the blocks fit into.

Anode ray

A contributor wrote, "Here, the electron hole gun might refer to the anode ray tubes." An anode ray is a beam of positive ions; these are actual particles and not "quasiparticles", and therefore the comic does not refer to them. 162.158.86.243 07:05, 20 August 2023 (UTC)

Who is firing the beam?

Are we so sure it's Beret Guy? Depending on how dangerous or destructive it is, it could be Black Hat? And is using the first person in the title text ("my") for a character like Beret Guy, instead of for a fictionalized Randall Monroe with weird hobbies, a departure from usual norms?