explain xkcd - User contributions [en]

2853: Redshift

2023-11-10T21:36:17Z

172.70.86.73: /* Explanation */

{{comic
| number = 2853
| date = November 10, 2023
| title = Redshift
| image = redshift_2x.png
| imagesize = 223x264px
| noexpand = true
| titletext = So do you have any plans for z=-0.000000000000045?
}}

==Explanation==
{{incomplete|Created by a SHIFTY RED MATTER BALL - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

In cosmology, redshift refers to the way that light from distant objects in the universe is stretched out, making it appear more red than it would otherwise. This occurs because the universe is expanding, and as a result, light waves are stretched as they travel through space. The "z" value is a dimensionless measure of the redshift. A higher "z" value, or redshift, corresponds to earlier times in the history of the universe. This is because as the universe expands, light from distant galaxies is stretched to longer, redder wavelengths as it travels towards us. The further away a galaxy is, the longer its light has been traveling, and thus the more the universe has expanded since that light began its journey. Therefore, a higher redshift indicates a galaxy that is further away and that the light we see from it left when the universe was younger. Conversely, a lower redshift means the light has traveled a shorter distance and time, indicating a more recent epoch in the history of the universe. Negative values of "z" indicate a blueshift, which indicate objects that are approaching the observer, generally used in cosmological work to calculate rotation speeds of nearby objects.

The joke here is that Cueball is asking another when they became interested in cosmology, and instead of giving a time like "in college" or "as a kid," they respond with a very precise redshift value "z=0.00000000038." This absurdly precise number is due to a highly recent event compared to the start of the universe, within the cosmologist's lifetime. The negative blueshift question in the title text is a playful way of asking about a future event, as it is approaching the speakers. Specifically it is a closer event to present day to when the cosmologist became interested in her field of study as the absolute value of z is 10^4 smaller and indicates a closer albeit future event.

Assuming a particular cosmology, and in particular values for the Hubble constant (H₀) and the curvature of the universe, it is possible to specify a particular look-back time. For z = 0.00000000038, and a flat Lambda CDM cosmology, with H₀ = 69.32 km / (Mpc s), a value of Ω₀ of 0.2865, a cosmic background temperature of 2.725 K, the look-back time is of around 1960 days, or five and a half years, which could suggest that the person started studying cosmology as part of a Ph.D. program.

Negative numbers of z would indicate a "look-forward" time, or a time in the future, and the same model indicates that z = -0.000000000000045 corresponds to about 5.5 hours in the future.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:Ponytail and Cueball are sitting at a table, eating dinner.
:Cueball: So, when did you first get interested in early universe cosmology?
:Ponytail: Sometime around Z = 0.00000000038

{{comic discussion}}

Talk:2229: Rey and Kylo

2023-07-31T03:52:34Z

172.70.86.73:

There should be discussion / analysis around the choice of "pandering" to cosmologists in this comic, as there has been a lot of outrage around the last few star wars movies that they are "pandering" to identities and diversity. [[Special:Contributions/172.68.174.112|172.68.174.112]] 22:34, 15 November 2019 (UTC)

Of course the Star Wars environs tend to be seen with the hue of conflict and not of peace. Our information derived from that long ago and that far away is going to be greatly red-shifted! [[Special:Contributions/162.158.154.199|162.158.154.199]] 00:36, 16 November 2019 (UTC)

Is ''The Force Awakens'' really the one that people accuse of pandering? If anything, I would think it's ''The Last Jedi.'' It not only had more progressive elements, it also heavy-handedly sold the "even you can be a Jedi" message to kids. --[[Special:Contributions/172.69.142.22|172.69.142.22]] 04:20, 16 November 2019 (UTC)
: Agreed, I have yet to see The Last Jedi (I tend to be very late, only catching movies when a TV channel airs them. I only just saw Rogue One), and I know I haven't seen the controversial one. The controversy I heard about centred around casting an Asian woman - who I think I've seen in some comedy videos so I expect to spot and recognize her - which casting lured all the racists out into the open (I still dunno why they thought she was a wrong choice, Star Wars has always had a huge variety of races both real and implied, I'm hoping that when I see the movie I'll find out). Then again, the Black Stormtrooper choice in Force Awakens seemed unquestionably pandering, they already established that all stormtroopers are clones of Jango Fett (and indirectly Boba Fett). Recruiting from a clearly non-sympathetic populace makes no sense, raising kidnapped babies (as I recall the explanation here) necessitates pure expense (housing, clothing, feeding, without any payback until they're old enough to fight) and training them themselves, and the problems with both is perfectly encapsulated in The Force Awakens, which is why they went with cloning an elite warrior in the first place, in the hopes of resulting in blindly loyal pre-trained soldiers. Feels like a blatant attempt to add a black character - which is extra stupid since as I recall the Fetts aren't even white anyway! LOL! (I have the exact same objection to making what's-her-face Brienne from Game Of Thrones the Silver Stormtrooper commander - despite that I loved her inclusion - but I haven't heard any complaints about her, probably because we never see her face in that movie) :) [[User:NiceGuy1|NiceGuy1]] ([[User talk:NiceGuy1|talk]]) 05:18, 16 November 2019 (UTC)

:: For me the problem is not the pandering to progressives. The problem is that it made "The Last Jedi" a bad movie, and a very, very bad Star Wars movie (like very out-of-character behavior of Luke, etc.). --[[User:JakubNarebski|JakubNarebski]] ([[User talk:JakubNarebski|talk]]) 10:51, 16 November 2019 (UTC)
:: Niceguy: while Star Wars did always have many ''alien'' races, and had Lando as significant (not comic, not first to die, not the usual kind of stereotype) character, there basically ''was'' only Lando as a notable (human) ethnic minority.
:: For my part (white anglo-scottish male, with all the boons and baggage that implies) I have absolutely no problem with the increase in screen-diversity (including the implication that all the Clone Troopers were all basically ethnicly Pacific/New Zealandesque, though by the time of the Original Trilogy it is canon that the Clone Troopers are phased out/supplemented by a regular mix of conscripts/volunteers. Thus, in the OT context, "white guys" as far as we can guess within their armour, as diverse as the rest of the background cast of humans in every aspect but for being very much all male.
:: Then in Force Awakens we find that the Empire's continuity organisation is now definitely more equal-opportunities employer/conscripter/shanghaier (revealed by Finn, and you've got Captain Phasma too though she may not have been through the ranks) though it seems more through necessity rather than a more 'woke' HR policy (in-universe!).
:: But I can take it all as it comes. The imminent one may mess with my headcan(n)on, or fancanon in general, but that remains to be seen. I can probably take it seriously (FCVO...), though I can't take seriously the typical people who use the term Social Justice Warriors - and especially its initialisation - in all seriousness (I don't think Jakub or anyone else here did that, in the way I mean) to define either Them or Us in the kind of arguments that some of the grungier corners of the internet tend to host.
:: Anyway, that's my thoughts on the matter, with all due apologies. [[Special:Contributions/162.158.154.199|162.158.154.199]] 17:12, 16 November 2019 (UTC)

I have to say I'm disappointed that Randall didn't mention the obvious problems. "A long time ago" - how long? "A galaxy far, far away" - how far? Which galaxy? Without these figures, any intergalactic attempt to pin down the variability of universal constants is doomed to failure. And let's be honest, if we DID have these figures, Kylo and Ren's efforts would likely be superfluous, as we can estimate things like the fine-structure constant through observations of lightsaber physics, Big G from the strength of the Force, and the curvature of spacetime by analyzing hyperspace travel. [[User:Cosmogoblin|Cosmogoblin]] ([[User talk:Cosmogoblin|talk]]) 08:46, 16 November 2019 (UTC)
:And something something something (darkside?) by knowing the optimal Mean Free Path in the Kessel Cluster has an upper limit of around 12pc [[Special:Contributions/162.158.155.200|162.158.155.200]] 15:05, 17 November 2019 (UTC)

The article says, " ... some movies and TV shows have spurred scientific innovations due to their subject matter (see below)." Then, nothing at all is said about the topic below. [[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 19:38, 30 July 2023 (UTC)
:It looks like the bulk of [https://www.explainxkcd.com/wiki/index.php?title=2229:_Rey_and_Kylo&diff=prev&oldid=183039 this edit] ([[User:NotaBene]], 17/Nov/2019) was removed at [https://www.explainxkcd.com/wiki/index.php?title=2229:_Rey_and_Kylo&diff=prev&oldid=183770 this point] (an IP editor, 27/Nov/2019).
:Personally, I'd prefer that section there for interest (and I can think of some other things we could add), but if that section is truly not supposed to be there then the 'orphan intro-reference' the IP neglected to remove can probably be deleted as well.
:You do a lot of fine-editing (which I ''mostly'' agree with/don't argue about) so I'll let you consider the question. Unless someone else jumps in before you... ;) [[Special:Contributions/172.70.162.183|172.70.162.183]] 20:42, 30 July 2023 (UTC)
::Yeah, my point was to ask other editors which was better, remove the reference or restore the material. [[User:Nitpicking|Nitpicking]] ([[User talk:Nitpicking|talk]]) 02:31, 31 July 2023 (UTC)
:::Sorry, I didn't see mention of how you'd tracked down the discrepancy. I thought you were actually looking for the reason. (My vote would be restore the purpose, BTW, as mentioned. But as I'm not an 'official' editor, I'm probably no more than cancelling out the whim of the no-username who originally decided it should be removed. It's probably necessary to have you/another opine to tip the balance over into actual action, fully resolving either way.) [[Special:Contributions/172.70.86.73|172.70.86.73]] 03:52, 31 July 2023 (UTC)

Talk:1774: Adjective Foods

2023-07-21T00:17:56Z

172.70.86.73:

Nobody has edited since I started this? Wow. I must have been ''early''. [[User:Jacky720|That's right, Jacky720 just signed this]] ([[User talk:Jacky720|talk]] | [[Special:Contributions/Jacky720|contribs]]) 15:23, 19 December 2016 (UTC)
:Nice to see somebody helping out! Thanks! [[User:Jacky720|That's right, Jacky720 just signed this]] ([[User talk:Jacky720|talk]] | [[Special:Contributions/Jacky720|contribs]]) 15:41, 19 December 2016 (UTC)

This looks just like all the food in my supermarket. I'm not even sure if I'm buying food or the best adjectives sometimes XD [[User:Fox Holmes|While most people have mass on Saturday, I have mine relative to my inertia]] ([[User talk:Fox Holmes|talk]]) 15:59, 19 December 2016 (UTC)

The can of Lite is a real thing, of course, and trademarked, which is why other beers can call themselves "light" but not "Lite". [https://www.beeradvocate.com/mag/2627/lite-beer-vs-light-beer/ This article has more on that.] [[Special:Contributions/162.158.75.4|162.158.75.4]] 16:05, 19 December 2016 (UTC)
I thought Lite could be a name for a drink itself, and then i found you. Cool.

Italics is totally fine, and Glazed and Lite ''are'' in white. [[User:Jacky720|That's right, Jacky720 just signed this]] ([[User talk:Jacky720|talk]] | [[Special:Contributions/Jacky720|contribs]]) 16:13, 19 December 2016 (UTC)
:First off, I would like to apologize, my reason for changing the text to normal could be seen as inflammatory, and that was not my intention. As for my actual reason, it's that while you may be able to read it fine, many people can't read text like that. In the comic, it's large and capital letters, but the wiki has small text. Adding all that guff makes it hard to read. For example, my mom has awful eyes, and text like that would be virtually unreadable to her. It was not for my sake, but rather for the sake of others. [[User:Fox Holmes|While most people have mass on Saturday, I have mine relative to my inertia]] ([[User talk:Fox Holmes|talk]]) 16:18, 19 December 2016 (UTC)
::It's not hard to increase the font size on a computer -- just ctrl and + (or ctrl and =). ctrl and - to turn it back down. The transcript is mainly there for search engines anyway, I imagine; after all, the comic is directly above it on the same page.[[Special:Contributions/108.162.237.178|108.162.237.178]] 17:29, 19 December 2016 (UTC)
:::it isn't hard to increase font size, but that's not what I'm talking about. I'm talking about how busy the text is. There is no reason for it to have that much. It distracts from the real purpose and decreases readability. Also, they want it edited as well. Note the box above the transcript about format. This is not about you. It needs to change for other people who cannot read this stuff as well. What makes you think everyone knows how to increase font size? I honestly didn't until now. You need to do something about it, I'll do it for you, which you may not like.[[User:Fox Holmes|While most people have mass on Saturday, I have mine relative to my inertia]] ([[User talk:Fox Holmes|talk]]) 17:48, 19 December 2016 (UTC)

Is "artisenal" even a word? Is that a purposeful misspelling of "artisanal"? (Like "lite" is a purposeful misspelling of "light".) [[User:Imperpay|Imperpay]] ([[User talk:Imperpay|talk]]) 16:42, 19 December 2016 (UTC)

The "artisenal" error has now been fixed in the updated comic. [http://xkcd.com/1774/]. --[[User:Esterhazy|Esterhazy]] ([[User talk:Esterhazy|talk]]) 17:42, 19 December 2016 (UTC)

The 'p' by a "kosher mark" indicates that it is kosher for Passover. It will say 'pareve' outright if the food is pareve. --Hamotron[[Special:Contributions/172.68.54.28|172.68.54.28]] 18:24, 19 December 2016 (UTC)

Who cares what foods ''might'' be in each of the packages? It has nothing to do with the comic and are generally speculation anyway. I'd disagree with most of what's written, but it doesn't matter. I would argue for removing the entire table/section. [[User:SeanAhern|SeanAhern]] ([[User talk:SeanAhern|talk]]) 18:58, 19 December 2016 (UTC)
:I'd generally agree. If we are to list them, the 'sack' should probably designate it as 'Flour or meal,' as cereals are sometimes steel-cut, but not usually stone-ground, and stone-ground wheat is flour. Also, while there are lots of kosher foods here, I've never seen kosher eggs. Rule seems to be it must come from a live kosher chicken, but I think all chickens are kosher while they are alive, & 'kosher chicken' refers to the manner of their slaughter. [[User:Miamiclay|Miamiclay]] ([[User talk:Miamiclay|talk]]) 23:07, 19 December 2016 (UTC)
:I don't think you are meant to be able to tell what is in the package as some of it makes no sense. Why would "cage free" be applied to flour or wheat? That is typically applied to chickens and their eggs to indicate the chicken/hen isn't trapped in a cage. But I have never heard of someone grinding a chicken. The only thing I can think of all those adjectives actually referring to would be ground up chicken such as for fertilisers. I think it is just a collection of adjectives which make no sense.[[Special:Contributions/108.162.249.160|108.162.249.160]] 00:00, 20 December 2016 (UTC)
::I do agree that there is no sense speculating about the contents of the packages with regard to the comic, but as an aside, I just have to comment that I routinely grind chickens to feed my cats! [[User:L-Space Traveler|L-Space Traveler]] ([[User talk:L-Space Traveler|talk]]) 23:41, 20 July 2023 (UTC)
Hear, hear; in fact I think the explanation should note that part of the joke is that no product could be described as cage free and stone-ground. similarly, fire-roasted and flambé are inconsistent. Also, smoked, sun-dried, <em>and</em> barrel-aged are very nearly mutually inconsistent. [[Special:Contributions/162.158.79.29|162.158.79.29]] 01:41, 20 December 2016 (UTC)
:: Disagree, fois gras could be made from cage free ducks and then ground with stone implements. [[Special:Contributions/108.162.221.64|108.162.221.64]] 14:36, 20 December 2016 (UTC)
:: It could refer to some baked good that uses stone-ground flour and eggs from cage-free chickens.[[Special:Contributions/172.68.46.5|172.68.46.5]] 17:05, 20 December 2016 (UTC)
`

This is the opposite of 993: Brand Identity. {{unsigned ip|162.158.62.75}}

"Stune-ground" might reffer to a "Ground stone" so its probably Flour. (PS hope i edit this correctly) {{unsigned ip|172.68.34.106}}

;Lite

The contents of the Lite can could also be soda, as it's well possible to produce a lite soda (though I don't think anyone has). {{unsigned ip|172.68.34.106}}
:Coca Cola has a Lite variety, so it certainly could be. [[Special:Contributions/141.101.104.219|141.101.104.219]] 14:10, 20 December 2016 (UTC)

;Original flavor

'Original flavor' actually isn't a noun phrase (in context). It's an adjectival phrase, which is why Randall has used it as he has. I'd suggest deleting this sentence in the explanation. {{unsigned ip|141.101.98.162}}

;Trivia
The link in the trivia section seems to point to the current comic image, not the older version.---- {{unsigned ip|108.162.219.100}}

Is it just me or is "original flavor" not an adjective? It seems to act as a noun, "flavor", being modified by an adjective "original", not as a phrase.
[[Special:Contributions/108.162.215.88|108.162.215.88]] 21:18, 22 December 2016 (UTC)

It's hard to read it as a noun phrase in context. In another context it could be, for example if a soda-can were a likely container for flavoring. Here it reads most naturally as an adjectival phrase: imagine 'Original flavor Coca Cola'. [[Special:Contributions/141.101.107.126|141.101.107.126]] 05:47, 23 December 2016 (UTC)Adam

Randall has been partially successful. I can walk into my local grocery and purchase packages of "loaf" and "spread", and bottles of "drink" [[User:These Are Not The Comments You Are Looking For|These Are Not The Comments You Are Looking For]] ([[User talk:These Are Not The Comments You Are Looking For|talk]])

;OSASCOMP
At first glance not all of these adjective orderings look natural. Has anyone checked? Opinion, size, age, shape, color, origin, material, purpose. ''— [[User:Tbc|tbc]] ([[User talk:Tbc|talk]]) 15:09, 23 December 2016 (UTC)''

I’m disappointed in myself. I thought the product was called bespoke.... [[User:Netherin5|Netherin5]] ([[User talk:Netherin5|talk]]) 14:02, 21 March 2019 (UTC)

;Authentic
I fairly regularly pass a road-side advert for something like "Authentic New York-style bagels" (though admittedly not regularly enough to be totally sure it's actually bagels, rather than pizza/whatever). I'm not anywhere near New York (much, much closer to the old York!), but the "-style" does so easily allow the "Authentic" to swap its actual meaning from something like "genuine" (which may be desirable, but also would mean correct usage being enforcable) to "copy" (which renders it meaningless either as an attraction or as regulator-bait that might provoke advertising standards prosecutions). So, without actually telling lies, they're attempting to evoke some mythical/illusiary status. Though I've no real idea what makes a bagel(/whatever) New York-style, anyway, so I really don't think I'd be able to identify 'inauthentic' ones either, except maybe containing less weasel... [[Special:Contributions/172.70.86.73|172.70.86.73]] 00:17, 21 July 2023 (UTC)

2800: Down

2023-07-11T11:49:49Z

172.70.86.73: /* Explanation */

{{comic
| number = 2800
| date = July 10, 2023
| title = Down
| image = down_2x.png
| imagesize = 611x290px
| noexpand = true
| titletext = It's just that I get nervous about heights.
}}

==Explanation==
{{incomplete|Created by a SOLAR COORDINATE SYSTEM. Do NOT delete this tag too soon.}}

The direction that we call "down" is usually defined as the direction in which objects on Earth fall, which, for all intents and purposes, is the same as the direction that points toward the center of the Earth. This direction is therefore relative, as it depends on where you are located in relation to Earth's center, and is different for people in different locations. For example, from an outside viewpoint, the direction of "down" for people in {{w|Madrid}}, Spain is the opposite of the direction of "down" for people in {{w|Weber, New Zealand}}, as these two places are located at {{w|antipodes|antipodal points}} on Earth.

It is possible to redefine "down" by choosing a different point of reference, such as the center of a ''different'' planet, which is the situation shown in this comic. We see [[Megan]] seated at a desk, which would be perfectly normal if not for the fact that the scene is shown at a completely unnatural, almost upside-down angle. Megan explains to [[Cueball]] that the direction of "down" was redefined to be relative to {{w|Mars}} instead of Earth. Since Mars is located in space many millions of miles away, this means that "down" could potentially be in almost any direction.

Redefining down to be relative to Mars would be impractical for people on Earth, as Mars is constantly moving with respect to Earth; this means that the direction of down will drift over time. Additionally, as Earth rotates once per day, the direction of down would also experience a 24-hour periodic wobble. It would be very difficult to keep track of this constantly-changing direction. Setting down relative to Earth's center avoids these problems (at least for beings on Earth!), as the Earth's center is static in relation to the motion and rotation of Earth.

Megan does not explain who exactly redefined down, or why they have the authority to do so, but it is most likely some scientific body such as the {{w|International Astronomical Union}}, which has the power to make such decisions - for example, the IAU demoted {{w|Pluto}} from a true planet to a {{w|dwarf planet}} in 2006. In reality, there is no governing body which determines the direction of down, nor periodically changes it. Nonetheless, in the world shown in this comic, it appears to happen frequently enough for Cueball to be frustrated by it.

It should also be noted that redefining down does not automatically alter the direction of gravity, which will still act in the same direction it did before. Therefore, it is unclear how Megan or Cueball are even aware of the change in definition, unless they are somehow {{tvtropes|MediumAwareness|aware of the comic they are in}} and "know" that they are oriented at a strange angle.

Cueball mentions that the redefinition of down is a side effect of redefining the origin of their coordinate system. A {{w|coordinate system}} is a way of representing locations in space using a set of numbers, where each number (called a coordinate) measures a distance travelled in one of the spatial dimensions. In order for these numbers to be meaningful, it is always necessary to define a single point as the origin, where all coordinates have the value 0. Locations can then be measured relative to the origin.

For example, a commonly-used coordinate system for Earth is the {{w|Earth-centered, Earth-fixed coordinate system}}, which defines the origin to be Earth's center of mass, and uses three pairs of points on the Earth's surface to define the directions of the three spatial dimensions; this allows any point relative to Earth to be specified as a triplet of three coordinates. Presumably, the coordinate system now used in the comic is a "Mars-centered, Mars-fixed" coordinate system, which would be good for things like launching satellites from Mars, but otherwise not very useful for most Earthly situations.

In the title text, Cueball states that he gets nervous about heights. Height is the distance between two points at different elevations, and elevation depends on which way "down" is - therefore, redefining down also redefines the concept of height. Since down now points toward Mars, and Mars is millions of miles away (about 34,000,000 mi or 55,000,000 km at closest approach), this means that Cueball - and indeed, everyone on Earth - is now standing at a height of about 34 million miles above Mars. However, it doesn't really make sense for Cueball to have such an anxiety in this instance - usually, when people are afraid of heights, it's because they are afraid of falling. However, gravity still points toward the center of the Earth, so Cueball is in no danger of falling to Mars.

The comic could also be a reference to the novel ''Ender's Game'' by Orson Scott Card, in which the protagonist, Ender, helps his team to orient themselves in a zero-gravity battle by noting that the directions "up" and "down" are arbitrary in space; he summarizes this with the mantra "The enemy's gate is down". This insight gives his team an anchoring point of reference which makes it easier for them to function in the gravity-less arena. This aspect of ''Ender's Game'' was previously referenced in [[241: Battle Room]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

:: [Megan is seated at a desk, in front of a laptop. The scene is rotated by 150° clockwise, so she appears to be upside down and angled.]

:: [Cueball enters the scene from the right side, behind Megan. He has three question marks below his head, oriented upright in frame.]

:: Megan: They announced that "down" is relative to Mars today.
:: Cueball: Ugh, I hate when they make another planet the coordinate system origin.

{{comic discussion}}

[[Category:Comics featuring Megan]]
[[Category:Comics featuring Cueball]]
[[Category:Physics]]
[[Category:Astronomy]]

2798: Room Temperature

2023-07-06T08:35:50Z

172.70.86.73: /* Explanation */

{{comic
| number = 2798
| date = July 5, 2023
| title = Room Temperature
| image = room_temperature_2x.png
| imagesize = 299x352px
| noexpand = true
| titletext = They're also refusing to fund my device that demonstrates uncontrolled hot fusion.
}}

==Explanation==
{{incomplete|Created by a LUKEWARM FUSION REACTOR - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

In this comic, Cueball presents a room-temperature [[wikipedia:Semiconductor|semiconductor]], consisting of layered silicon crystals. He enthusiastically describes the properties of his "discovery", namely that it can be tweaked to amplify or switch the flow of electric currents, but his audience is not impressed. This might be because silicon crystal semiconductors are already widely in use as a [[wikipedia:Semiconductor_device|key component of electronic systems]].

It appears that Cueball has confused semiconductors with [[wikipedia:Superconductivity|superconductors]] - materials that have an electrical resistance of absolute zero, meaning the flow of electrons is not slowed down at all (resistance can be thought of as the electrical equivalence of friction). Superconducting properties are extremely desirable since they allow for the lossless flow of electric current, as opposed to regular conductors like copper which have a low but non-zero resistance so the electric current decreases over time and distance. However, the known superconductors only work at extremely low temperatures close to 0 K, so their practical use is very limited. The discovery of superconductors that work above the boiling point of nitrogen (77 K or -196 °C) was a big deal because it meant that relatively cheap liquid nitrogen could be used as coolant rather than liquid helium. The discovery of a superconductor that works at room temperature (293 K) would be a much bigger deal and would likely earn the discovering scientist(s) a Nobel prize.

In the title text, Cueball talks about a device that produces “uncontrolled [[wikipedia:Nuclear_fusion|hot fusion]]” which is also not met with enthusiasm. Again, this is likely due to the fact that it has already been discovered and used - in the form of [[wikipedia:Thermonuclear weapon| hydrogen bombs]]. ''Controlled'' hot fusion could be useful as an [[wikipedia:Fusion_power|alternative power source]] for nuclear reactors (which currently use nuclear ''fission''); however, [[wikipedia:Tokamak|current implementations]] still require more energy than they create. Cueball probably confused this with [[wikipedia:Cold_fusion|''cold'' fusion]] which is a purely hypothetical nuclear reaction that would take place at room temperature. If real, this process could provide large amounts of cheap energy, but so far all experiments that were claimed to have achieved cold fusion were found to be severely flawed and the results could not be replicated.

It should be noted that both "discoveries" presented in the comic were in fact very big and important discoveries back in their day. The proposal that nuclear fusion is what powers stars earned [[wikipedia:Hans_Bethe|Hans Bethe]] the Nobel price in Physics, and semiconductors are what allow modern electronic devices to be so small, as their properties make it possible to selectively steer the flow of electrical current, [[wikipedia:Integrated_circuit|even over an extremely small area]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[A single frame with a table in the middle. To the left of the table stands a Cueball, and to the right of the table stands Megan and another Cueball.]

:Cueball: My layered silicon crystals can amplify or switch current while sitting right here on the table!
:Ponytail: Uh huh.
:Another Cueball: I see.

:Caption: No one is impressed by my discovery of room-temperature semiconductors.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Multiple Cueballs]]
[[Category:Physics]]

2798: Room Temperature

2023-07-06T08:34:24Z

172.70.86.73: /* Explanation */

{{comic
| number = 2798
| date = July 5, 2023
| title = Room Temperature
| image = room_temperature_2x.png
| imagesize = 299x352px
| noexpand = true
| titletext = They're also refusing to fund my device that demonstrates uncontrolled hot fusion.
}}

==Explanation==
{{incomplete|Created by a LUKEWARM FUSION REACTOR - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

In this comic, Cueball presents a room-temperature [[wikipedia:Semiconductor|semiconductor]], consisting of layered silicon crystals. He enthusiastically describes the properties of his "discovery", namely that it can be tweaked to amplify or switch the flow of electric currents, but his audience is not impressed. This might be because silicon crystal semiconductors are already widely in use as a [[wikipedia:Semiconductor_device|key component of electronic systems]].

It appears that Cueball has confused semiconductors with [[wikipedia:Superconductivity|superconductors]] - materials that have an electrical resistance of absolute zero, meaning the flow of electrons is not slowed down at all (resistance can be thought of as the electrical equivalence of friction). Superconducting properties are extremely desirable since they allow for the lossless flow of electric current, as opposed to regular conductors like copper which have a low but non-zero resistance so the electric current decreases over time and distance. However, the known superconductors only work at extremely low temperatures close to 0 K, so their practical use is very limited. The discovery of superconductors that work above the boiling point of nitrogen (77 K or -196 °C) was a big deal because it meant that relatively cheap liquid nitrogen could be used as coolant rather than liquid helium. The discovery of a superconductor that works at room temperature (293 K) would be a much bigger deal and would likely earn the discovering scientist(s) a Nobel prize.

In the title text, Cueball talks about a device that produces “uncontrolled [[wikipedia:Nuclear_fusion|hot fusion]]” which is also not met with enthusiasm. Again, this is likely due to the fact that it has already been discovered and used - in the form of [[wikipedia:Thermonuclear weapon| hydrogen bombs]]. ''Controlled'' hot fusion could be useful as an [[wikipedia:Fusion_power|alternative power source]] for nuclear reactors (which currently use nuclear ''fission''); however, [[wikipedia:Tokamak|current implementations]] still require more energy than they create. Cueball probably confused this with [[wikipedia:Cold_fusion|''cold'' fusion]] which is a purely hypothetical nuclear reaction that would take place at room temperature. If real, this process could provide large amounts of cheap energy, but so far all experiments that were claimed to have achieved cold fusion were found to be severely flawed and the results could not be replicated.

It should be noted that both "discoveries" presented in the comic were in fact very big and important discoveries back in their day. The proposal that nuclear fusion is what powers stars earned [[wikipedia:Hans_Bethe|Hans Bethe]] the Nobel price in Physics, and semiconductors are what allows modern electronic devices to be so small as their properties make it possible to selectively steer the flow of electrical current [[wikipedia:Integrated_circuit|even over an extremely small area]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}

[A single frame with a table in the middle. To the left of the table stands a Cueball, and to the right of the table stands Megan and another Cueball.]

:Cueball: My layered silicon crystals can amplify or switch current while sitting right here on the table!
:Ponytail: Uh huh.
:Another Cueball: I see.

:Caption: No one is impressed by my discovery of room-temperature semiconductors.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Ponytail]]
[[Category:Multiple Cueballs]]
[[Category:Physics]]

Talk:2797: Actual Progress

2023-07-04T07:12:26Z

172.70.86.73:

So true! If the outliers look weird, it's often because you've misunderstood something about the whole set.
[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 17:11, 3 July 2023 (UTC)

It may be good to start to ask whether your nice obedient little line is just a coincidence in your testing data. [[Special:Contributions/172.71.26.159|172.71.26.159]] 17:22, 3 July 2023 (UTC)
:By the time you've happily worked out why the strange exceptions aren't actually strange/exceptions, you realise that there's no real underlying reason that carefully regiments the 'clearly patterned' bits and that's just a pure artefact of data... [[Special:Contributions/172.70.86.132|172.70.86.132]] 18:24, 3 July 2023 (UTC)
:Related: You have two numbers which are supposed to be same but differs. Sure there is small bug in computing one of them ... and sure you find it, fix it ... and the difference became about twice as big. -- [[User:Hkmaly|Hkmaly]] ([[User talk:Hkmaly|talk]]) 20:10, 3 July 2023 (UTC)

When I read it, helped also by the title, I thought at scientific research more than software engineering. So I felt the explanation slightly off - not sure if I am alone. [[User:Vdm|Vdm]] ([[User talk:Vdm|talk]]) 22:12, 3 July 2023 (UTC)
:For me it reminded me of something I was doing recently. Boiling down some text, within which were numeric values (allied to descriptors that related to what those numeric values were). Dealt with the the distinction between floating point and (intentionally, not just coincidentally) integer numbers in various places, but then had to deal with various other notations. The first surprise was negative small values (should have been ~0, perhaps, for 0<=x<MAX, but smudged and badly re-normalised before getting into my hands), then there was exponential notations (multiple types), and then there was a set like 4.30k, 8.05M, 5.46T, 8.12Qu, 3.67Qi (had to presume {{w|Long and short scales|Short Scale}} was in use, despite being the more illogical version) which I only discovered by checking for word-boundary exceptions for values when checking there weren't any currency or unit-of-measure aspects I needed to be aware of. When I process what I've extracted a bit more, no doubt I'll find other things to add to my edge-condition checklist. But it's already been 'fun' getting past the hurdles I know about!
:Now, this isn't really what I think the comic is about (at its core, even if closely related), and I think the Explanation is a little too bloated/all-over-the-place at the momemt already so I won't try to add anything from this experience in there as well. Just recording my own prosaic tale of recent experience, which probably says more about my bad choice of source data than anything else... [[Special:Contributions/172.70.86.73|172.70.86.73]] 07:12, 4 July 2023 (UTC)

2791: Bookshelf Sorting

2023-06-20T14:50:26Z

172.70.86.73: /* Explanation */

{{comic
| number = 2791
| date = June 19, 2023
| title = Bookshelf Sorting
| image = bookshelf_sorting_2x.png
| imagesize = 425x255px
| noexpand = true
| titletext = Of course, I sort all my bookshelves the normal way, alphabetically (by first sentence).
}}

==Explanation==
{{incomplete|Created by a BOOKSHELF SORTED THE NORMAL WAY. Do NOT delete this tag too soon.}}

Some people like to sort their bookshelves by the visible color of the book's spine, for example by hue to create a rainbow effect. This is pleasing to the eye, but unhelpful when [https://www.youtube.com/watch?v=AYxmPHLU9oA trying to find a specific book]. For literary enthusiasts (AKA "Book People"), this arrangement could be seen as annoying, as they would like to be able to find specific books when they need them, and would more likely sort them by the author's last name, or by a more rigorous organizational scheme such as the {{w|Dewey Decimal Classification}}.

Unfortunately, [[Randall]] has found a ''much'' worse method of book organization - instead of sorting the books as discrete units, he has sorted their individual ''pages'' by number. This would require physically dissecting each book into its individual pages, and then organizing them into groups by page number. This organization method has a number of significant drawbacks. Firstly, it would be rather time-consuming to take each book apart. Adding a book to the shelf would also be extremely inefficient, as Randall would have to locate the correct group to insert each page into. Since books can be hundreds of pages long, there could easily be hundreds of page groups on the shelf. The reverse operation - taking a book from the shelf - would also now be significantly more difficult since one would have to locate all of the book's individual pages - if the pages have no identifying marker to indicate which book they originally came from, it may even be impossible, especially since no secondary sorting has been specified, so, for example page 1 of a book could appear early in the group of page 1s, while page 2 of the same book could appear towards the end of the group of page 2s. In practice, though, Randall appears to have sorted secondarily by length of book, from longest to shortest (which accounts for the repeating patterns seen in the size of the pages).

Taking books apart also effectively destroys the book, losing all of the physical benefits of having pages bound as a single unit, such as portability and durability. Without their protective cover, the pages would be more susceptible to damage, loss, or disruptions such as drafts. It would also reduce the resale value of the book.

It should be noted that the term "page" has an ambiguous meaning when referring to physical pages - "page" can refer both to the numbered page, and to the sheet of paper that the page is printed on. For books, this distinction is important as most books print on both sides of the paper - thus, a single sheet actually comprises ''two'' numbered pages. Randall's system appears to work by absolute physical page count, including the front and rear covers as 'pages', so that the front cover is the first 'page'. All the front covers are on the left side, then the first internal leaf of each book (counted as the second page), then the second internal leaf, etcetera. This produces repeating patterns of taller and shorter loose-leaf pages, echoing the proportions of each cover, having gathered together each a page of the same position in each different book. The back covers are mixed in to whatever group falls after the last internal leaf from the same book, and so are intermixed with pages from longer books. At the end, there are only the last pages of the longest book left, now all uniform in size, and its rear cover.

Sorting by color has no practical use (beyond possibly that of making an aesthetic appearance), but this distribution of books, makes them useless in all situations and makes for an erratic display, potentially susceptible to disordering knocks and drafts.

The caption claims that this is a way of sorting that "book people" hate, even more so than sorting by color of the cover/spine. It is not clear if the spine part is thrown away or just not visible, maybe being sorted towards the wall. This would make it a sort of antithesis to color sorting, not only is it not sorted by color, but the spines that usually define the color sorting are either to the back or fully removed. It might be the intent to have "the absolute opposite" of color sorting and follow this idea ad absurdum.

In the title text Randall begins by saying that he of course sorts his bookshelf alphabetically, like book people, but then he states that he sorts books by first '''sentence''' instead of the book author or book title. This is somewhat impractical for many purposes of finding, as people then cannot find a book they haven't read (and remembered the first sentence). But at least it doesn't destroy the books and can also be accomplished by a quick glance inside each book (which bibliophiles should certainly enjoy, if it does not distract them from the task at hand) rather than having to pay much attention to exactly how you shuffle and collate many loose-leafs. You can use something like a simple {{w|merge sort}} to arrange the shelf from scratch, or do a {{w|binary search algorithm|binary search}} to find where to insert individual new books.

In addition, some books have very well-known first lines, such as "It was the best of times, it was the worst of times" ({{w|A Tale of Two Cities}}) and "It is a truth universally acknowledged, that a single man in possession of a good fortune, must be in want of a wife" ({{w|Pride and Prejudice}}). So, sorting by first line would not only be practical in some cases, but it could used to demonstrate a level of literary sophistication on the part of the bookshelf owner.

==Transcript==
:[A bookshelf hanging on a wall is shown. It is covered almost from left to right but not with ordinary books. To the left there are 11 covers next to each other without any paper between them. They have different heights and shades of gray. After the last of these there follows many leaves of paper of differing heights similarly to that of the covers. The top of the papers thus form a wave shape with more than twenty peaks before they reach another cover. After that there follows similar patterns with paper in different height and then a cover in between more papers. But there is a much shorter distance between the first and second cover than before the first cover, after the initial 11 covers. The next two covers are close to the first, then there is a longer stretch of paper to the fourth, much less to the fifth, and then the next three covers comes very close. There is again quite long distance to the ninth and tenth cover, and here the number of different heights for the paper are clearly less than the previous paper stretches. Finally before the last and 11th cover all the paper, not much of it though, are of the same height, and just a bit lower than the final cover. The 11 covers at the start matches the 11 covers later and they comes in reverse order throughout the paper stretches as they are sorted to begin with, so the first and last cover matches, as does number 2 and the second last etc. There is a caption beneath the panel:]
:Book people hate seeing books sorted by colors, but it turns out they get ''way'' more angry if you sort the pages by number.

{{comic discussion}}