Talk:2825: Autumn and Fall

2023-09-08T04:00:16Z

162.158.155.160: Replies and calendar nerdiness.

:Who calls it the "fall equinox"? I thought the equinoctes were always described as "vernal" and "autumnal"? [[User:Mathmannix|Mathmannix]] ([[User talk:Mathmannix|talk]]) 19:11, 6 September 2023 (UTC)

:: Americans sometimes call it the fall equinox casually [[Special:Contributions/172.71.158.100|172.71.158.100]] 19:56, 6 September 2023 (UTC)

:: In American English, "fall equinox" contrasts with "spring equinox" in the same way "summer solstice" contrasts with "winter solstice." The Latinate names are "autumnal equinox," "hibernal solstice," "vernal equinox," and "estival solstice," but since British English lost its non-Latinate name for the fall, the term "autumnal equinox" has to do double duty. The Latinate names are rather more common for equinoxes than solstices, but all four names are used. Also used are "September equinox," "December solstice," "March equinox," and "June solstice" if the context doesn't let you commit to one hemisphere or the other. [[Special:Contributions/108.162.216.74|108.162.216.74]] 09:20, 7 September 2023 (UTC)

:: Most people? It is the equinox that falls in Fall. So the Fall equinox. Like the summer and winter solstice. Which also invalidates anybody claiming the summer soltice being the last day of spring.[[Special:Contributions/172.69.150.102|172.69.150.102]] 16:08, 7 September 2023 (UTC)

:WRT the alt text, perhaps this is a woosh moment, but "fall" isn't at all common in British parlance. We know it, but only as an Americanism of what we would just call "Autumn". [[Special:Contributions/172.68.19.103|172.68.19.103]] 20:55, 6 September 2023 (UTC)
:: That's the joke. Just as Americans don't typically use "autumn", the UK does not use "fall". [[Special:Contributions/172.69.34.12|172.69.34.12]] 21:45, 6 September 2023 (UTC)

What "type of five-season system shown in the comic"? The comic doesn't show five-season system. It shows EIGHT season system. We just only know names of five of them. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 23:17, 6 September 2023 (UTC)

: That's the point, though: if the English language had an 8-season system, we'd have 8 names for them — but we only have 5. [[Special:Contributions/162.158.110.225|162.158.110.225]] 07:05, 7 September 2023 (UTC)

: Canada has 11 seasons with names for all of them: https://twitter.com/mathewi/status/1234532208423178241?lang=en (one of many variations on this meme, but rings very true if you live up north)

I think the statement "nowhere uses the type of five-season system shown in the comic." deserves an actual "citation needed" and not the joke one. Personally I didn't know about the six season thing in South Asia so it's not obvious that noone uses 5 seasons. [[User:Bischoff|Bischoff]] ([[User talk:Bischoff|talk]]) 11:07, 7 September 2023 (UTC)
::I definitely agree. I was going to comment the same thing.[[Special:Contributions/172.70.178.11|172.70.178.11]] 12:51, 7 September 2023 (UTC)
::The Hebrew bible, in the Book of Genesis (Gen. 8:22), establishes six seasons (consistent with the west-Asian origin story of the progenitors of the Hebrew race) of Sowing, Reaping, Cold, Heat, Summer, and Winter.

Can you believe it guys? First day of fall. Just a week away! First day of fall is in a week! Woohoo! I am so happy about this information. first day of fall, just a week away. Oh wow. Can you believe it? First day of fall! Just in a week! It got here so fast. First day of fall! [[Special:Contributions/172.71.22.39|172.71.22.39]] 11:51, 7 September 2023 (UTC)Bumpf

I'm surprised he didn't find a way to work in the "unofficial" seasons, which are based on holidays that straddle the periods of summer weather. In the US, Memorial Day is the unofficial start of summer, and Labor Day the unofficial end. They also coincide approximately with school summer breaks. [[User:Barmar|Barmar]] ([[User talk:Barmar|talk]]) 14:20, 7 September 2023 (UTC)
: I just saw this comment, but that's exactly what I just added. :-) [[Special:Contributions/162.158.79.161|162.158.79.161]] 23:40, 7 September 2023 (UTC)

I'm just unreasonably pleased that someone of note is acknowledging that calling the equinoxes & solstices, the "start" of a season, is absurd from the standpoint of tracking the weather: The shortest day, occurring near the meteorological ''middle'' of winter even in the most delayed climates, is ''obviously not'' the "start" of winter, & likewise the weather shifts noticeably about a month before the vernal & autumnal equinoxes. The seemingly obligatory "first day of summer!" proclamations in the middle of June feel ''really'' disingenuous & annoying when much of the continent has already been seeing 90°F\32°C for weeks. '''By what means can we collectively petition to abolish this obviously incorrect practice''' & start ''properly'' referring to the solstices & equinoxes as the ''middle'' of their respective seasons, instead?
[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 16:30, 7 September 2023 (UTC)
:As a science teacher, I feel this a lot.
::By the way, if you take a look at the difference between Gregorian and Julian calendars, the Gregorian calendar was designed to correct for the 0.25% imprecision of the Julian calendar, so Julian dates for the equinoxes and solstices are actually ~16 days later than Gregorian dates for the same. Hence why Orthodox religions observe different dates for Xmas and Easter. (Interestingly, the Jewish calendar was codified before the Gregorian calendar was proposed, and the Jewish calendar tries to unite lunar and solar cycles [according to the 19-year Metonic cycle], so Jewish dates having to do with the solar revolution are only accurate in the Julian calendar.)
:It's actually a classic trick question, "Do days get longer or shorter in winter?". Days are shorter (than in summer), yes, but given that winter quite famously can be said to {{w|Winter#Astronomical and other calendar-based reckoning|start on the shortest day}}, means that the answer is actually "longer", as the season heads towards the equinox and nights shorten from their maximum. (Either that or "neither, they're ''all'' 24 hours long" ...well, give or take the occasional leap second...)
:So, anyway, it's astronomical seasons. [[Special:Contributions/172.70.85.230|172.70.85.230]] 17:06, 7 September 2023 (UTC)

2817: Electron Holes

2023-08-21T00:45:32Z

162.158.155.160:

{{comic
| number = 2817
| date = August 18, 2023
| title = Electron Holes
| image = electron_holes_2x.png
| imagesize = 295x331px
| noexpand = true
| titletext = They tried to report me to the authorities, but because I had the device they couldn't charge me.
}}

==Explanation==
{{incomplete|Created by a BEAM OF EXCITONS - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
An {{w|electron hole}} is a quasiparticle denoting a ''lack'' of an electron. These are fundamental in the theory and design of semiconductors and discussed in many educational tracks regarding electronics engineering. Creating a beam that is made out of a lack of a thing is not possible{{citation needed}}, otherwise we'd have "dark beams". It should be noted however, that a hole in the QED vacuum is a real particle, known as the positron. See the {{w|Dirac sea}}.

Wikipedia gives a good basic explanation of the concept of the "electron hole":

<blockquote>[A]n electron hole (often simply called a hole) is a quasiparticle denoting the lack of an electron at a position where one could exist in an atom or atomic lattice. Since in a normal atom or crystal lattice the negative charge of the electrons is balanced by the positive charge of the atomic nuclei, the absence of an electron leaves a net positive charge at the hole's location.

Holes in a metal or semiconductor crystal lattice can move through the lattice as electrons can, and act similarly to positively-charged particles. They play an important role in the operation of semiconductor devices such as transistors, diodes (including light-emitting diodes) and integrated circuits. If an electron is excited into a higher state it leaves a hole in its old state. . . .

In solid-state physics, an electron hole (usually referred to simply as a hole) is the absence of an electron from a full valence band. A hole is essentially a way to conceptualize the interactions of the electrons within a nearly full valence band of a crystal lattice, which is missing a small fraction of its electrons. In some ways, the behavior of a hole within a semiconductor crystal lattice is comparable to that of the bubble in a full bottle of water.</blockquote>

In this cartoon, the physicist is upset that the idea of the electron hole beam doesn't "make sense" - because a beam consisting purely of things that are "missing" doesn't seem possible; electron holes only exist in the context of a background field of electrons in which just a few are missing - yet the beam is still working to destroy her belongings (or at least create dramatic visual effects) and eventually she resorts to exclaiming simply "Stop it!"

The caption below the comic states that physicist''s'', plural, were angry about this device, implying that this is not the first physicist whose lab he has interfered with. It also implies that the off-screen character—likely [[Beret Guy]], considering his history of seemingly impossible feats and powers—is not a physicist, notably separating them from {{w|Randall Munroe}}, who is. The physicists are also likely angry that they themselves could not come up with such a device, as well as that something as groundbreaking and innovative (as well as seemingly impossible) is being used solely for the purpose of creating chaos.

The title text plays on a double meaning of "charge". When the word is used with "authorities", it's an accusation. However it can also refer to an electric charge. The implication is that the authorities are trying to charge him with electrons (which carry a negative electric charge), but due to the device he can {{w|Carrier generation and recombination|recombine}} the electrons with his electron holes, thus making the authorities unable to "charge" him.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Ponytail, who has her fists clenched and a squiggle above her head, is standing in front of a desk, a beam of electron holes is being fired at a printer on the desk; the beam is shown reacting to the printer, dispersing lightning bolts and 'particles' but causing no obvious damage. There are little '+' signs distributed along the beam and in the circles around the printer, though they're much easier to see in the higher-resolution version of the strip that's displayed if one zooms in on the original comic page.]
:Ponytail: This doesn't even make sense! They're quasiparticles, not real-
:Off-panel voice: ''Pew pew pew''
:Ponytail: ''Stop it!''

:[Caption below the panel:]
:Physicists got ''really'' mad about my device that fires a beam of electron holes.

{{comic discussion}}

[[Category:Science]]
[[Category:Comics featuring Ponytail]]
[[Category:Physics]]

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Talk:2825: Autumn and Fall

2817: Electron Holes