explain xkcd - User contributions [en]

2904: Physics vs. Magic

2024-03-09T19:43:24Z

Jmatxx: /* minor correct of two typos */

{{comic
| number = 2904
| date = March 8, 2024
| title = Physics vs. Magic
| image = physics_vs_magic_2x.png
| imagesize = 740x294px
| noexpand = true
| titletext = 'At the stroke of midnight, your brother will be hurtling sideways at an altitude of 150 meters' is a regular physics prediction about your nonmagical trebuchet, whereas 'you are cursed to build a brother-launching trebuchet' falls out of the Lagrangian.
}}

==Explanation==
{{incomplete|Created by THE ILVERMORNY PROFESSOR OF THERMODYNAMICS- Please change this comment when editing this page. Do NOT delete this tag too soon.}}

This is a comic about the differences between magic and physics. [[Miss Lenhart]], a school teacher, says that {{w|physics}} is applying forces to objects continuously over time, while magic tells you the outcome, but not how it'll get there. She gives an example of a magical curse that causes the recipient to slay their brother by midnight; it's not science because it doesn't say what will cause them to take this action. She then states that the {{w|laws of thermodynamics}} and other laws are also magic, with {{w|Lagrangian (physics)|Lagrangians}} being deep magic.

The joke is that these basic physical laws have been discovered empirically, but we don't know ''why'' they're true. So by the logic in the second panel, they're essentially like magic, since they specify a result without explaining how we get there. It may be possible to derive some of them from the others, but eventually we hit bottom and we have to say "because it just is", and that's like magic.

The second panel alludes to Newtonian mechanics, which is formalized mathematically as an initial value problem; that is to say, the initial conditions of a system are known, and the rules relating the current condition of a system to the evolution of that system over time are specified. As humans, we are used to thinking of the present being a known state and the immediate future depending only on the present, so the Newtonian formalism makes intuitive sense as a picture of the world. The last panel contrasts this humorously with a series of physics ideas which violate this basic assumption in increasingly unsettling ways.

Thermodynamics, in particular equilibrium thermodynamics, the most studied branch and that most familiar to physics students, frames its questions in terms of the most likely state for a system to evolve to eventually. In this sense, the predictions of thermodynamics do not depend on the present state of the system, and do not help predict its intermediate behaviour. They only predict what the state of the system will be after a long enough time has elapsed for the system to have stopped evolving; in other words, to have reached equilibrium. Looked at in this way, Thermodynamics seems to violate the principle outlined in the first panel; however, most people will be intuitively comfortable with the idea that one can ask sensible questions about long term stability without considering the details of how the system gets there.

Conservation laws arise naturally from Newtonian physics, but it is not necessarily clear intuitively how. Low level explanations tend to take the form of an understandable but fairly un-illuminating derivation from calculus and elementary algebra, while at a more advanced level they are shown to relate to symmetries of a physical system in a way which is very general and powerful, but nonetheless extremely abstract and mysterious. Either way, the end result- a conservation law- is a statement about how a system will be for ever, regardless of its evolution. This also violates the principle stated in the first panel, and it violates it in a way which seems intuitively stranger than thermodynamics.

Lagrangian mechanics is a reformulation of classical physics. It is exactly equivalent to Newton's laws. However, while Newtonian Mechanics is formulated in terms of specific forces acting on an initial state, and allows one to predict the final state by evolving the system forwards in time, Lagrangian mechanics instead takes the initial and final states of a system as inputs, and gives a rule which states which trajectories between those states are physically allowed. This is apparently a direct contravention of the principle in the first panel. In fact, it much more closely resembles the definition of magic given; one of the most surprising and counter-intuitive facts in physics is that the intuitive Newtonian worldview is exactly mathematically equivalent to the magical-seeming Lagrangian and closely related Hamiltonian pictures. For this reason the comic refers to Lagrangians (the central tool of lagrangian mechanics which serves as a description of the system dynamics) as 'Deep Magic', as it is really the ultimate expression of the 'magical' side of Physics.

{{w|Teleology}} is a branch of causality often associated with religion or magical thinking, that argues from the end result, instead of the cause of things.
In this sense, the comic may also be alluding to disputes about possible teleological aspects of the {{w|stationary-action principle}}, that can be used to derive Newtonian, Lagrangian and Hamiltonian equations of motion, and even general relativity, as well as classical electrodynamics and quantum field theory.
For simple classical systems it can usually be stated as follows:"Given that the particle begins at position x1 at time t1 and ends at position x2 at time t2, the physical trajectory that connects these two endpoints is an extremum of the action integral." The Wikipedia article goes on to state: "By specifying some but not all aspects of both the initial and final conditions (the positions but not the velocities) we are making some inferences about the initial conditions from the final conditions, and it is this 'backward' inference that can be seen as a teleological explanation."
However, since the principle can be used to derive both integral laws (that appear to be arguing from the result) and the usual differential laws (that appear to be arguing from the cause), one can argue that these seemingly contradictory forms of causality are in fact not contradicting each other, since they are mathematically equivalent.

The title text seems to be mixing the diagram shown on the whiteboard with the curse of the comic. The first prediction is (according to Miss Lenhart) a physics prediction about a nonmagical {{w|trebuchet}}, whereas the second prediction would be something from deep magic.

==Transcript==
:[Miss Lenhart is standing in front of a whiteboard and pointing to it with a stick. The whiteboard contains two lines of scribbles at the top, two drawings below them featuring a curve on the left and a circle on the right, and below them four additional lines of scribbles with smallest line of scribbles in the lower left corner.]
:Miss Lenhart: '''''Physics''''' and '''''magic''''' are different in a very deep way.

:[Close-up of Miss Lenhart pointing the stick to the left to a depiction of a projectile's motion due to gravity. The path of movement is shown as a dashed line that first heads directly to the right but starts increasingly curving downward. There are five small circles at different points within the path. There are labels "V0" for an arrow pointing right on the left side of the leftmost circle, "F" for an arrow pointing downward below the leftmost circle, and "T0" to "T4" for the five individual circles from left to right.]
:Miss Lenhart: '''''Physics''''' works by describing the forces that act on a system.
:Miss Lenhart: To predict outcomes, we progressively apply those forces over time.

:[Miss Lenhart is holding the stick down and standing in front of Jill and Hairy sitting at their desks. Jill has her hands on her desk while Hairy has his hands on his lap.]
:Miss Lenhart: '''''Magic''''' specifies the outcome, but not the intermediate events.
:Miss Lenhart: '' "Ere the clock strikes twelve, you are cursed to slay your brother" '' is magic, not science.

:[Same setting as in the third panel, except Miss Lenhart is holding the stick slightly lower and Jill has her other hand on her lap.]
:Miss Lenhart: ... And that's how we know thermodynamics is magic.
:Miss Lenhart: Conservation laws are, too.
:Hairy: What about Lagrangians?
:Miss Lenhart: '''''Deep''''' magic. Speak not of them here.

{{comic discussion}}

[[Category:Comics featuring Miss Lenhart]]
[[Category:Comics featuring Jill]]
[[Category:Comics featuring Hairy]]
[[Category:Physics]]
[[Category:Trebuchet]]

899: Number Line

2023-12-01T16:49:59Z

Jmatxx: Fixed typo

{{comic
| number = 899
| date = May 16, 2011
| title = Number Line
| image = number line.png
| titletext = The Wikipedia page List of Numbers opens with "This list is incomplete; you can help by expanding it."
}}

== Explanation ==

Once again, [[Randall]] seems to be just messing around, this time with a number line.

*'''Negative numbers''' have the same magnitude as positive numbers but can only be used to represent the removal of that same magnitude (hence the term "difference" being used for subtraction).

*'''0.99'''.... is {{w|0.999...|equal to 1}} because if you subtract any number from one, however small, you will get a number that is less than 0.99. 1 − '''0.0000000372''' is 1 bit less than the {{w|IEEE_floating_point|IEEE 754 32-bit floating-point representation}} of 1.

*The '''{{w|golden ratio}}''' or '''ϕ''' (phi) is the number <math>\tfrac{1+\sqrt{5}}{2}</math>, about 1.61803. It has many interesting mathematical properties, mostly relating to geometry, and has occasional appearances in nature, such as spirals formed by the seeds in sunflowers. It is also subject to many less credible claims, such as the belief that phi appears in {{w|Parthenon}} (a well-disputed claim) or that rectangles proportioned after phi are more aesthetically pleasing. The speaker seems to drive off his listeners as soon as he brings it up; the golden ratio is infamous for being brought up by know-it-alls, which Randall has mocked in other comics.

* The approximate range from 2.1 to 2.3 is marked as '''The Forbidden Region'''. Why Randall marked this range as forbidden is really anyone's guess; it seems to be an entirely arbitrary designation.

*'''{{w|e (mathematical constant)|e}}''' (Euler's number) is 2.71828... and '''π''' (pi) is 3.14159265...

*'''2.9299372''' is probably a {{w|President's Day}} reference. It is the average of e and π just as the American Presidents' Day is always observed on the 3rd Monday of February (between {{w|George Washington}} and {{w|Abraham Lincoln}}'s birthdays). Washington and Lincoln were the 1st and 16th Presidents of the USA, respectively. Each has a celebrated place in American history.

*'''{{w|Gird}}''', '''ᛟ''' is a purely fictional number. (The glyph that Randall uses seems to resemble an older shape of the digit 4, such as seen on [http://www.bl.uk/learning/images/mappinghist/large2296.html archaic maps].). Canon and orthodox could mean "accepted as the offical story" and "most science-based followers", but they could also reference to organised religions. Gird could be a reference to any or all of:
**[http://strangehorizons.com/fiction/the-secret-number/ Bleem] - a fictional integer between 3 and 4
**iCarly's [http://icarly.wikia.com/wiki/Derf Derf] - a fictional integer between 5 and 6
**George Carlin's [http://www.urbandictionary.com/define.php?term=bleen Bleen] - a fictional integer between 6 and 7
**[https://scp-wiki.wikidot.com/scp-033 SCP-033] - a fictional "missed number" that causes mathematical systems to break down when it is introduced to them (manifesting as the physical destruction of the objects the mathematical formuli are contained in, such as paper and computers)
**Saturday Morning Breakfast Cereal's [http://www.smbc-comics.com/index.php?id=3913 Sorf] - a fictional integer between 2 and 3 

*'''Site of Battle of 4.108''' is another map joke, implying that 4.108 is an actual location, where an eponymous battle was previously fought. It may be a reference (or homage) to the {{w|Battle of Wolf 359}}, a famous military conflict in the fictional universe of Star Trek. 4.108 was also referenced in [[2861: X Value]], though with an added 3 in the ten-thousandths place.

*An '''Unexplored''' region obscures the line approximately ranging all values from 4.5 to 6.7. In the days when the Earth was still being mapped out, territories that had yet to be properly explored and charted were labelled in a similar manner. The placement of the '''Unexplored''' region on the number line indicates that all numbers in that range, including the integers 5 and 6, are completely unknown. This is, of course, patently ridiculous, and the humor seems to derive solely from how nonsensical and unbelievable it is. Correspondingly, the digits 5 and 6 cannot be found in the comic.

*It is often the case in the media that "It has been 7 years..." or "In the last 7 years..." etc. It is made to seem like a believable statistic but cannot always be true. Alternatively, it is intended as an absurd joke that the number 7 is just "not to be believed".

*'''8''' is not the largest even {{w|prime number}}, nor is it a prime at all. The largest (and only) even prime is 2. A joke intended for those who clearly know that the claim is false.

*The last entry seems to be a reference to certain fields of {{w|pure mathematics}}, which focus less on performing calculations with numbers and more on understanding structures that may be described using logic. It finishes off the tone of the comic that seems to be shaping the number line terms of what is commonly useful to certain areas of applied mathematics, rather than a complete, accurate version of the number line.

The title text is a literalism joke; at the time the comic was published, all Wikipedia articles with incomplete lists began with the message template "This list is incomplete; you can help by expanding it." In the case of the {{w|List of numbers}} page, one could infer the absurd notion that Wikipedia wanted to have the list include every number from negative infinity to infinity. But because all Wikipedia articles are necessarily finite, such a list would always be incomplete, no matter how much it was expanded. It may also be referencing his previous statements about Wikipedia being the home of compulsive list-makers, who make the most astonishingly complete lists imaginable.

As of 2022, Wikipedia's List of numbers page, as well as all pages including lists that cannot ever reach a state of completion, are headed by the message template "This is a dynamic list and may never be able to satisfy particular standards for completeness. You can help by adding missing items with reliable sources."

== Transcript ==
:[Number line ranging from −1 to 10.]
:[Arrow pointing left, towards negative numbers] Negative "imitator" numbers (do not use)
:[Line right before the number one] 0.99... (actually 0.0000000372 less than 1)
:[Line at the golden ratio.] Φ Parthenon; sunflowers; golden ratio; wait, come back, I have facts!
:[Line at a region between two and 2.2] forbidden region
:[Line at Euler's number.] e
:[Line a bit before 3] 2.9299372 (e and pi, observed)
:[Line at π.] π
:[Line at 3.5 with ᛟ as the numeral] Gird – accepted as canon by orthodox mathematicians
:[Line a bit after 4.] site of battle of 4.108
:[Blob between 4.5 and 6.5 labeled unexplored.]
:[Line at seven.] Number indicating a factoid is made up ("every 7 years...", "science says there are 7...", etc)
:[Line at eight.] Largest even prime
:[Line at 8.75.] If you encounter a number higher than this, you're not doing real math

== Trivia ==

* As for the "Gird" between 3 and 4, one might argue that the arithmetic square root of 11 may have some "integer" properties, because there exists an integer-to-integer (citation needed) function f(x) such that f(f(x))=11x. (details needed)
* The "unexplored" area is actually famous for some numbers such as "Twice Euler's constant" (also known as Tau, approximately 6.283185).

{{comic discussion}}
[[Category:Math]]
[[Category:Wikipedia]]

2795: Glass-Topped Table

2023-06-29T16:10:41Z

Jmatxx: /* grammar */

{{comic
| number = 2795
| date = June 28, 2023
| title = Glass-Topped Table
| image = glass_topped_table.png
| titletext = You can pour a drink into it while hosting a party, although it's a real pain to fit in the dishwasher afterward.
}}

==Explanation==
{{incomplete|Created by a pair of GLASSES.}}
A play on the common term for a table, such as a dining or coffee table, that has a glass surface. "Glass-topped table" usually means the table top is made of glass, but in this comic the phrase represents, instead, a table with a glass surface where surface has been "topped" with a drinking glass. Notably, the glass is part of the table top, merged with the regular glass surface so that the glass can not be lifted off of the table. This would thus require the use of a straw to drink from it.

Furthermore, the otherwise normal-looking drinking glass looks like it has been placed over the edge of the table and is about to fall off. This could make anyone unfamiliar with the table likely to automatically reach out for the glass to prevent what appears to be an imminent disaster. This could potentially have unfortunate consequences, since the glass is not independently movable without shifting the entire table. Assuming the person does not hurt their hand or arm from the unexpected load as they take the strain through sheer reflex, they may successfully move the glass ''and entire table'' to cause other things on/adjacent to the table to be toppled/struck sideways.

It is not certain if the advertisement for this item makes this configuration clear. By its name alone, buyers might expect to get an ordinary table with a glass surface, but few of them would be interested in buying one when they discover the extra glass attached and the caption says this is the least popular item in their furniture store. At first glance, in a store, most people would be drawn to 'prevent the imminent accident' and end up thwarted or creating other problems. In a web-page/catalogue picture, the glass would just look like part of the scenic depiction presentation of the table, albeit a weird one. It is not unusual that a table in a commercial would feature glasses, or other accessories artfully placed upon it, to give it a sense of scale and contextual use, but the dissonance of the 'carelessly' positioned glass would work against the usual advertising pressures employed. Anyone who still ordered the table, without establishing the true nature of its permanent feature, is also then likely to complain and negotiate a refund/replacement (negating whatever sales were actually made) and write bad reviews (discouraging others from even looking at the product).

The title text adds to this by saying it would be difficult to put the glass in a dishwasher, since you would need to bring the table with it. There are dishwashers [https://www.thekbzine.com/pages/13317/worlds_largest_dishwasher_unveiled/#:~:text=Bosch%20unveiled%20the%20world's%20largest,water%20and%20stay%20perfectly%20dry big enough] to fit tables, but they are not for regular households.{{cn}} And that won't make moving the table any easier. Cleaning the glass after a drink would thus have to be done by hand, and the water in the glass has to be sucked out, mopped up or drained by inverting the whole table (or entire top, if detachable) in a non-damaging way.

==Transcript==
:[The comic shows a square table with a glass surface. The glass surface is not clear enough to see through. A drinking glass stands nearly half-way over the right edge of the table, so it looks like it is in 'danger' of falling. Apparently, however, is seems that this glass is merged with the glass surface of table, thus it cannot fall off. There is a caption below the panel:]
:The least popular item at my furniture store is probably the table with a decorative drinking glass built into the edge of the glass top.

{{comic discussion}}


[[Category:Food]]
[[Category:Puns]]

2790: Heat Pump

2023-06-17T16:15:57Z

Jmatxx: /* Grammar */

{{comic
| number = 2790
| date = June 16, 2023
| title = Heat Pump
| image = heat_pump_2x.png
| imagesize = 740x400px
| noexpand = true
| titletext = If I'm not going to upgrade to a powered one, I should at LEAST stop leaving the door open so often.
}}

==Explanation==
{{incomplete|Created by a BIG CHUNGUS HEAT PUMPER. Do NOT delete this tag too soon.}}

This comic appearing on 16 June, 2023 could be in reference to the conversation in German media and politics about a [https://www.theguardian.com/world/2023/jun/14/germany-coalition-staves-off-implosion-with-11th-hour-heating-law-amendment controversially drafted law] to regulate heating systems in homes and buildings.

A {{w|heat pump}} is a system which applies the {{w|ideal gas law}} to transfer heat from a relatively cold area to a relatively hot area, i.e. to heat an insufficiently warm room/building or to cool an insufficiently chilled room/building, even if the outside air is at the opposite heat-gradient for the purpose. The extra energy used to achieve this prevents the {{w|second law of thermodynamics}} from being violated, and is usually assumed to be added to the warmer side of the system. This is why the back of a refrigerator will feel hot, as it maintains the cooler internal temperature (and why leaving its door open does not cool down the room that it is in, just heats it up as it fruitlessly attempts to both heat and cool the same air-mass).

In this comic, [[Cueball]] has a ''manual'' heat pump, and he is manually heating an area by walking from the warm area (colored in ''red'') to a colder area (colored in ''blue''), and "drawing" residual heat into the "bellows" (accordion-shaped device) by expanding them to cool them below the outside air temperature (more intense blue). He then returns back to the warm area and compresses the bellows to concentrate heat above the sustained room-temperature (more intense red), then letting it radiate away and increasing room temperature before going back outside to repeat the process of drawing heat out of the cooler air. As expected, this is a laborious process, as captioned in the text below the panel. Manual heat pumps of this kind do not exist in real life{{cn}}, but are partly emulated by devices such as {{w|fire piston}}s. The {{w|air source heat pump}} effectively does the same thing as this comic, but by using components installed across a wall (letting fluids/vapors flow between the two sides) rather than moving physical components through doors.

The title text refers to the problem of having to open the door to carry the device in and out. This would let the warmed air flow out, and cool air flow in, to undo some of the effort used to attempt to increase the difference. In lieu of some device that does not require the door to be opened at all, he should at least promptly close it between each passage through it.

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

:[Cueball indoors (light red background) holding a (matchingly light red) accordion-shaped device in his hands and walking towards an open door.]

:[Cueball outdoors (light blue background) with the door closed, the device is still light red.]

:[Cueball extends the device and it turns blue.]
:''Release''

:[Cueball looks behind while the device has turned light blue to match the area it is in.]

:[Cueball walking back inside through an open door, the device is still light blue.]

:[Cueball indoors with the door closed. He squeezes the device and it turns red.]
:''Squeeze''

:[Cueball looks at the door while the device is glowing in bright red.]
:''Radiate''

:[Cueball is leaving the indoors area (now having a slightly more intense red background, to closely match the now less bright red of the device) through an open door.]

:[Caption below the panel:]
:Manual heat pumps are such a pain.

{{comic discussion}}
[[Category:Comics featuring Cueball]]
[[Category:Comics with color]]
[[Category:Physics]]

2673: Cursed mRNA Cocktail

2022-09-17T18:25:16Z

Jmatxx: /* added info about the CDC and Dr. Fauci */

{{comic
| number = 2673
| date = September 16, 2022
| title = Cursed mRNA Cocktail
| image = cursed_mrna_cocktail_2x.png
| imagesize = 331x513px
| noexpand = true
| titletext = Serve one each to guests whose last cursed cocktail was more than 2 months ago.
}}

==Explanation==
{{incomplete|Created by a VACCINE DRINKER. Do NOT drink the mRNA Cocktail. Do NOT delete this tag too soon.}}

Approximately two dozenth in [[:Category:Comics featuring cursed items|the "cursed" series]], this comic describes a process to approximate the molecular composition of certain {{w|mRNA}}-based vaccines in drinkable form. It contains the variety and relative concentrations of the simple molecular constituents found within the injectable mixture. i.e. mostly water, some sugar, lipids, proteins and either an {{w|Glutamic acid|amino acid}} salt ''or'' biological and genetic material, and the other constituents of {{w|mayonnaise}}.

Like much of what we eat or drink, the stomach and intestines will neutralise much of the complexity of either the vaccines or this ersatz replica of them, reducing them to simpler proteins of some slight nutritional value. For the vaccine to work, it has been designed to be injected into the body e.g. {{w|intramuscular}}ly to bypass the hostile environment of the human digestive system. While there are similar vaccines administered as a nasal spray, the fragility of mRNA in the human digestive system has curtailed the search for ingestible analogs. [[Randall]]'s replacement mixture '''might provoke generally unwise physiological reactions.''' While very few people would find such a mixture palatable, it is likely nontoxic, and contains water, proteins and calories, all important if elementary nutritional components. Because it doesn't contain a complete spectrum of essential amino acids, vitamins, and minerals,{{Actual citation needed}} you can't live on it alone.

The instruction to serve in {{w|shot glasses}} is a play on words as "shot" can mean {{w|Injection (medicine)|injection}} in medicine. (U.K.: {{wiktionary|jab#Noun|jab}}; Scotland: {{wiktionary|jag#Noun|jag}}). One {{w|Jigger (bartending)|jigger}} is only 0.19 of a cup, so the recipe serves up to five. This comic coincided with the widespread availability of the bivalent COVID [https://www.fda.gov/news-events/press-announcements/coronavirus-covid-19-update-fda-authorizes-moderna-pfizer-biontech-bivalent-covid-19-vaccines-use vaccines in the US.]

The CDC (Centers for Disease Control and Prevention) is the national public health agency of the US government. They make recommendations about vaccine use. Dr. Anthony Fauci has been the chief medical advisor to numerous US Presidents and has often been interviewed on television regarding the COVID-19 vaccines.

The title text suggests the mixture can be served as a "booster" to a prior dose or serving after an initial treatment. There is much study of vaccine efficacy relative to the timing of subsequent doses. Too little time between makes the new dose not necessarily cause the immune system to react in the way that it should; however most pairs of distinct vaccines work well if delivered on the same day.{{Actual citation needed}} The comic recommends not redosing within two months of the last attempt.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:Ever wondered what it would be like to drink the new COVID booster?
:This recipe approximately recreates the taste and nutritional profile!
:''(Note: does not protect against COVID.)''

:[The following two testimonies are displayed in spiky bubbles.]
:"...What? Eww." -CDC spokesperson
:"Please stop." -Dr. Anthony Fauci

:Ingredients
:2 cups water
:3 tbsp mayonnaise
:¼ tsp MSG or nutritional yeast
:1 tbsp sugar

:Directions
:Pour 1 cup of water into a blender. Add the mayonnaise and MSG. Blend until smooth.
:Pour the other cup of water into a glass. Add the sugar and 1 tsp of the mixture from the blender. Stir well.
:Serve in shot glasses.

{{comic discussion}}
[[Category:COVID-19]]
[[Category:Biology]]
[[Category:Comics featuring cursed items]]
[[Category:Comics featuring real people]]
[[Category:Food]]

2625: Field Topology

2022-05-27T19:21:48Z

Jmatxx: /* removal of unnecessary words */

{{comic
| number = 2625
| date = May 27, 2022
| title = Field Topology
| image = field_topology.png
| titletext = The combination croquet set/10-lane pool can also be used for some varieties of foosball and Skee-Ball.
}}

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

This comic strip depicts a logical extreme of multi-use athletic facilities, in which sports are grouped by the topological equivalence of their fields (not to be confused with {{w|Field (mathematics)|mathematical fields}}, or the {{w|Fields Medal}} prize -- although successfully {{w|Straightedge and compass construction|constructing}} these fields might lead to medals of one kind or another being granted).

In topology, shapes which can be smoothly changed into one another, without making or closing cuts or holes, are equivalent. {{w|Baseball}}, {{w|soccer}}, and {{w|tetherball}} are played on fields with no obstructions, so they are grouped ({{w|Group (mathematics)|heh!}}) into one continuous field without holes. The goals on a soccer field do not create holes; because the goalposts are connected to the field with a net, the goals and field are topologically equivalent to a plane. The same is true of ice hockey, as well.

{{w|Volleyball}} and {{w|badminton}} are played on a field split in two by a net, and the {{w|high jump}} has a bar that contestants jump over. The space bounded by the bottom of the net (or bar), the supporting poles, and the ground can be considered to be a hole, so their fields all have one "hole".

A basketball court has two holes, the nets. Parallel bars can be thought of as two rectangles and thus as two topographical "holes". A football field is a special case. Commonly, an American football field uses a "Y" shaped upright, making the field topologically equivalent to a plane. However, at lower levels of play (primary and secondary schools), sometimes an "H" shaped upright is used, which creates a topological hole under the crossbar at both ends of the field. The comic might instead refer to Gaelic football or Rugby, both of which use "H" shaped goals and are called "football" in certain contexts.

The lane dividers in swimming create bounded holes on the 'playing surface' equivalent to the number of lanes minus one. And each hoop in croquet is a hole with one edge bounded by the playing surface.

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

Four indistinct shapes with various numbers of holes in, with signs next to them

zero holes: "Baseball. Soccer. Tetherball."

one hole: "Volleyball. Badminton. High jump."

two holes: Basketball. Football. Parallel bars."

nine holes: "Olympic swimming. Croquet."

Image caption: "No one ever wants to use the topology department's athletic fields."

{{comic discussion}}

2575: What If? 2

2022-01-31T18:23:17Z

Jmatxx: /* fixed five or six typos. */

{{comic
| number = 2575
| date = January 31, 2022
| title = What If? 2
| image = what_if_2.png
| titletext = CLARIFICATION: By 9/13, I mean September 13th, not the 9th day of Jancember, the cursed 13th month that exists between December and January in the transdimensional temporal plane.
}}

*This comic came out just a few minutes after the [[Countdown in header text]] finished. The countdown was to the revelation in this comic!
==Explanation==
{{incomplete|Created by a RESIDENT OF JANCEMBER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic is [[Randall]]'s way of announcing and [[:Category:Book promotion|promoting]] his new book, ''what If? 2'', based on his [[what if?]] blog and following his first what if book.

The entire comic as well as the new [[xkcd Header text]] is a link to a [https://xkcd.com/what-if-2/ what if? 2: the book] page on {{xkcd}}.

Randall ensured the maximum possible attention to his announcement by placing a [[Countdown in header text|countdown]] in the [[xkcd_Header_text#2022-01-10_-_Standard_text_with_countdown|header]] about three weeks prior to the announcement. This has caused a lot of speculation as to what would be revealed on the day of this comic's release 2022-01-31. The timer was inside a panel at the top right of the xkcd Header text together with the standard header text: ''xkcd updates every Monday, Wednesday, and Friday''. Inside the panel a picture began emerging after the first day, but the picture only changed approximately once every four hours. After a few weeks was it certain that it was a plane that was being revealed. And on the second to last day, around twenty days onwards, it was clear that it featured a dinosaur standing on top of the plane and it might have been possible to guess the relation to the "what if?" canon. On or prior to the day before the announcement on xkcd, however, Amazon made visible a preorder page for the book, so the answer was made clear about a day before Randall had intended.

Until then, however, there were numerous [[Countdown_in_header_text#Theories|theories]] about the [[Countdown_in_header_text#Countdown|countdown]] and what the [[Countdown_in_header_text#The_picture|image would reveal]], as the image gradually changed throughout the eventual [[Countdown_in_header_text/images|135 frames]].

In the title text Randall feels that he must clarify the release day, since he has often joked about the way different countries (and people) write dates - he did not use the one version he himself had promoted in earlier comics. He does however give two different versions of the release date: the first is "9/13" in the first panel, which is at least (usually - see below) only readable one way; harder to misinterpret is the more expansive "Sep 13, 2022" in the final panel. What he should have written was, "the book is released on 2022-09-13," using the international standard as defined in the {{W|ISO 8601}} standard and used in [[1340: Unique Date]].

The clarification reads: By 9/13, I mean September 13th, not the 9th day of Jancember, the cursed 13th month that exists between December and January in the transdimensional temporal plane.

Since there are only 12 months in the year 2022,{{citation needed}} then 9/13 actually cannot be mistaken, while 9/12 might be. So there was really no need for this clarification, especially with the last text in the last panel. So this is of course just a title text joke, where he can manage to make a [[:Category:Portmanteau|portmanteau]] of January and December, Jancember, and then then call this a cursed month, since it would be the 13th month, if it came before New Year. This comic came out at the end of January, so it could have been at the end of Jancember instead. The number thirteen is seen by many as an unlucky number, so a thirteenth month would be considered cursed by some, or at least unlucky.

==Transcript==
:[Randall, drawn as Cueball, is throwing his arms out as he stands next to a big red book with white drawings on the cover. The cover shows a large passenger plane that has just taken off, as can be seen since the landing gear still has the wheels extended (only one wheel is visible at the middle part and then the one in the front). A Tyrannosaurus Rex has jumped on to the plane and it is biting down on the ceiling of the plane a bit in front of the wings, as if on the back of a prey. The dinosaur has already broken through the ceiling. Below is a jagged landscape with small mountain like peaks in the background. Megan and Cueball are standing on the top of the second of two raised plateaus, looking up at the plane and dinosaur. There is unreadable white text above the plane, then a title beneath the plane, and the authors name below the landscape, and more unreadable text beneath that, all in white. Below the book, there is a small arrow pointing to the right bottom of the book, with a label beneath.]
:Randall: '''Announcement:''' I’m publishing a ''what if?'' sequel!
:Book cover: what if? 2
:Book cover: Randall Munroe
:In stores 9/13, available for preorder now: xkcd.com/whatif2

:[Randall is shown holding up his smart phone in one hand. The screen lights up as indicated with small lines at the top. These point up to at least six SMS texts, each with two lines of text. They are shown in speech bobbles with a small arrow in the bobbles lower left corner. All six are covered partly by either the other five, or by Randall’s head, and none of them can be read in any meaningful way; only parts of sentences or words are clearly visible. The bobbles and the text in them are all drawn in gray. Randall is narrating (not speaking) in this panel, both above the SMS texts, and below.]
:Randall narrating: Ever since I wrote '''''what if?''''', I’ve been flooded with questions.
:Randall narrating: And not just from readers- My friends and family stated texting them to me, too.
:Text 1: Hey could s.. ele
:Text 2: Hypothe…
:Text 3: If you s… Jupiter…
:Text 4: Could my c… or…
:Text 5: Do you… my car…
:Text 6: If I trie… The Sun…
:Randall narrating Honestly, I love it.

:[Randall is again standing next to his red book talking. There is also a second version of the book lying to the right of the closed book, and this has been opened up to reveal two pages. The text is unreadable and the images are very hard to see, but it seems that two people are standing next to each other on the right page. The image at the top of the left page has been enlarged and shown to the right of the open book. It is an image of the Earth that is being peeled by a potato peeler, which takes off a large peel from the north part of Scandinavia and then goes via Russia into Asia. The title and author name can still just be read on the book,but maybe only because they are already known...]
:Randall: The questions are so good. People have asked about touching exotic materials, traveling across space and time, eating things they shouldn’t, and smashing large objects into the Earth. There are questions about lasers, explosions, swingsets, candy, and soup. Several planets are destroyed-one of them by the soup.
:Book cover: what if? 2
:Book cover: Randall Munroe

:[Zoom in on the top part of Randall speaking on.]
:Randall: Like the first book, '''''what if? 2''''' also features collections of short answers, new lists of weird and worrying questions, and some of my favorite answers from the What if site.

:[Only the closed red book are shown in this panel, in an even larger version than in any of the previous panels. But it is still only the title and the author name that can be read, but in this version these can also be read on the spine of the book. Randall is narrating again, and there are text both above and below the book.]
:Randall narrating: If you want to get it when it’s released, you can preorder a copy at xkcd.com/whatif2
:Book spine: what if? 2 Randall Munroe
:Book cover: what if? 2
:Book cover: Randall Munroe
:Randall narrating: Available Sep 13, 2022

{{comic discussion}}

[[Category:Comics with color]]
[[Category:Comics featuring Randall Munroe]]
[[Category:What If?]]
[[Category:Book promotion]]
[[Category:Portmanteau]] 
[[Category:Calendar]] 
[[Category:Dinosaurs]]

2570: Captain Picard Tea Order

2022-01-20T18:47:06Z

Jmatxx: /* Typo */

{{comic
| number = 2570
| date = January 19, 2022
| title = Captain Picard Tea Order
| image = captain_picard_tea_order.png
| titletext = We can ask the Earl for his order once he's fully extruded from the dispenser.
}}
*This was the fifth comic to come out after the [[Countdown in header text]] started.

==Explanation==
{{incomplete|Created by EXTRUDED EARL GREY- Please change this comment when editing this page. There would be way too many additional [[285: Wikipedian Protester|citations needed]] for it to work here. Do NOT delete this tag too soon.}}

Captain {{w|Jean-Luc Picard}} is a primary character in the in the science fiction TV series ''{{w|Star Trek: The Next Generation}}'', which is focused on the crew of a starship. The ship is equipped with {{w|Replicator (Star Trek)|replicators}}, which can create virtually any object or material requested, including food and drink, and which responds to verbal commands.

In the show, Picard's beverage of choice is {{w|Earl Grey tea}}. His habitual method for ordering is to first specify what he wants (tea, in this case), then specify a particular type (Earl Grey), and then give specific instructions for how it is to be served (hot, as opposed to {{w|iced tea}}). Because this is his favored drink, he repeatedly places the exact order "[https://www.youtube.com/watch?v=iaAT6-dY1QI Tea. Earl Grey. Hot.]" The first picture in the strip implies that the display shows each part of the order, and provides a list of options for the next step.

[[Randall]] parodies this repeated order by suggesting [[#Other Words|other words]] that could follow "Tea. Earl Grey.", starting from ones considered "normal" moving to those presumed increasingly "less normal" down a long and winding arrow.

The results of two examples from the normal/less-normal scale are also illustrated: Sticky tea and loud tea. Sticky is kind of obvious, though perhaps not immediately understandable, but the loud version is a tea that screams "Teeee..." The vibrating and screeching teacup may be a reference to the various ''Star Trek'' episodes about {{w|tribble}}s, which behave in a similar way in the presence of Klingons.

The very last qualifying addition, the least normal is not a single word but "Tea for him, too." This reinterprets the meaning of the standard introductory words, suggesting that "tea", and "Earl Grey" are separate orders, which implies that he wants the replicator to produce tea, then produce Earl Grey (either one of the {{w|Earl Grey}}s or a person named Grey with the given title of Earl), then a second tea to serve to this newly created person.

In contrast to the often trivial use of a replicator as merely a potentially infinitely versatile vending machine, the comic sets up a number of quite esoteric options, culminating in Earl Gray himself potentially drinking (generic) tea, after both the tea and he have been replicated into existence by Picard.

In the title text, someone tells Picard that they should wait until the Earl has been fully extruded from the dispenser, and ''then'' ascertain what he would actually wish to drink. The presumption is that it could take some time to get a full living person out of the replicator.

In the various versions of ''{{w|Star Trek}}'', it's established that {{w|Replicator_(Star_Trek)#Origins_and_limitations|replicators aren't capable of producing living things}}, so this version of the order would not be canonically possible.

===Other Words===
{| border =1 width=100% cellpadding=1 class="wikitable"
! Word !! Explanation
|-
| Hot
| A fairly normal word to be used when ordering tea. Although that it even needs specifying is itself a clue that other variations (such as "Iced", below) are available. This is the chosen word of the five visible words Picard is potentially presented with in the first drawing. The act of requesting this is thus illustrated, though not of the appearance of the tea itself.
|-
| Iced
| {{w|Iced Tea}} is a 'normal' variation of tea.
|-
| Decaf
| Traditional teas (from {{w|Camellia sinensis}}) tend to have caffeine in them. Asking for {{w|Decaffeination|decaffeinated}} tea is not particularly uncommon if the drinker requires it. In the series ''Picard'', set several decades after ''The Next Generation'', Picard does actually order "Tea, Earl Grey, decaf" in [https://tvline.com/2020/01/26/star-trek-picard-premiere-easter-eggs-earl-grey-decaf/ one scene].
|-
| Good
| A normal, subjective term. Most people drinking tea would want it to be good, but to specify it like this would perhaps be strange. This is one of the words in the first drawing, as a listed alternative to Hot.
|-
| Lukewarm
| While this is a temperature that tea can be at, most people do not want their teas to be lukewarm.
|-
| Tasty
| Similar to good, most people would want their tea to be tasty, or at least flavorsome.
|-
| Boiled
| Boiling the water used to make the tea is a common and normal way to increase the flavor and nutrients extracted from the tea leaves, though it is suggested that the actual ideal temperature of hot water is 75-98°C (167-210°F), according to whether it is a light tea or a dark one, and that perhaps it should be sipped at around 65°C/150°F-ish if desired 'hot'.
Having made a tea and ''then'' bringing it back to the boil (especially after adding milk/etc.) may destroy some of the desirable qualities previously imbued.
|-
| Watery
| Tea is a drink that often involves water, but this perhaps suggests over dilution or under infusion in some way.
|-
| Sour
| Many people do not enjoy a sour taste, which can accompany rot and is a strange thing to specify when ordering Earl Grey tea. Although lemon juice is often an additive used in the same way (but as a complete alternative) to milk.
|-
| Meaty
| Most teas are plant-based.
|-
| Solid
| Tea is usually drunk as a liquid. It would be strange to ask for solid tea.
|-
| Dry
| Tea is a liquid typically made with water and may have milk. A dry version might be either unmade (e.g. tea leaves in their un-infused form) or freeze-dried back into a dehydrated form.
"Dry" can also be used to describe {{w|Dryness (taste)|a "mouth feel"}} in a [https://www.reddit.com/r/explainlikeimfive/comments/2f1gxx/eli5_how_can_a_drink_taste_dry/ variety of drinks] ''or'' {{w|Prohibition|enforced alcohol-free scenarios}}. For the latter option, it can assume a default serving with an {{w|Hot_toddy#Variations|alcoholic component}}, or an entirely {{w|Long Island iced tea|alternate basis}} for the beverage, which the request needs to be specify it is not.
This is one of the five words Picard was seen presented with in the first drawing.
|-
| Raw
| This describes tea that has not been "cooked", so it would just be tea made with room-temperature water. This is {{w|Iced_tea#Sun_tea|possible}} but generally takes many hours.
|-
| Deep-fried
| Tea is not usually deep-fried. But you'll probably {{w|Deep-fried Mars bar|find someone}} who has tried it, [https://www.pitco.com/blog/deep-fried-liquids-trend one way or another].
|-
| Sticky
| Perhaps significantly dehydrated, or thickened with enough of a hydrophilic substance, this would produce something very unlike most teas that would usually be requested.
This scenario is illustrated to show a clearly messy product that awkwardly sticks to and drips from the replicator as well as Picard.
|-
| Grilled
| Tea is not usually grilled.
|-
| Fossilized
| Since tea is a liquid, it would be tricky to figure out how to fossilize it.
|-
| Magnetic
| Tea is not magnetic. Magnetic metals would have to be added to the tea, which would not be pleasant to drink.
|-
| Ballistic
| Usually, the replicated beverage is deposited in a stationary cup, but Picard could ask for it to be dropped or thrown out instead.
|-
| Unstable
| This word is often used to refer to radioactive or explosive materials, which hopefully is not a property that would apply to something meant to be ingested. Alternatively, this could imply that the receptacle into which the tea is delivered should be unstable - being unbalanced, or lacking a flat bottom. This is likely to lead to the tea being spilled.
|-
| Blessed
| Tea is a beverage, and it may be strange to ask a machine to create 'blessed' tea. However, if the machine were to use holy water, already blessed by a human, it is [https://www.quora.com/When-does-Holy-water-lose-its-Holiness-If-its-boiled-is-the-resulting-water-vapor-still-considered-Holy-Does-it-lose-its-Holy-property-when-it-transfers-into-a-gas-Is-it-still-Holy-when-it%E2%80%99s-frozen#:~:text=In%20other%20words%2C%20as%20long,else%2C%20it%20remains%20holy%20water.&text=a%20simple%20change-,Never.,He%20is%20faithful possible] for it to remain "blessed" after the water is used to make tea. It is also possible that this is a reference to tea which could be used in [http://www.archbishoplefebvre.com/blog/baptism-can-i-use-any-liquid baptism].
In role-playing games, items can be Blessed, i.e. having greater positive or lesser negative effects. This includes potions, a class of drinks that do not usually include any teas but could contain the "potion of water", which may also, therefore, be the basis of this blessed brew.
|-
| Blurry
| Being blurry is not a normal state for tea to have. Cloudy, on the other hand, is quite normal for certain brews.
|-
| Loud
| While molecules in tea (especially hot tea, and vitally so in an {{w|The Hitchhiker's Guide to the Galaxy (novel)|Infinite Improbability Drive}}) do move vigorously, this does not usually result in distinct audible effects.
However, as illustrated, it seems the requested cup of tea is produced capable of emitting a high-pitched, high-volume whining sound that entirely dominates the vicinity. It actually appears to somewhat vocalize what it is, Teeeee...
|-
| Virtual
| Virtual tea cannot be produced physically, so asking a physical tea machine for it would be very strange. However, it might be useful on the holodeck.
|-
| Intravenous
| This means the tea would be injected directly into the customer's veins, likely a very painful experience if the tea comes out boiling. Instrument of choice would probably be a {{w|Infuser|''tea infuser''}}.
|-
| Expanding
| In a sense, most hot tea is expanding: as the water in the tea evaporates, it becomes much less dense, increasing in "size".
But most people would probably argue that the evaporated water is no longer part of the tea. Water, like most materials, usually expands as it increases in temperature—except between freezing and about 4° C, where it has the unusual property of {{w|Water_%28molecule%29#Density_of_water_and_ice|''contracting slightly''}} as temperature increases. If tea behaves similarly despite the extra dissolved compounds, then "expanding tea" would describe any tea between 4° C and boiling point. Possibly beyond, and explosively so, if {{w|Superheating|superheated}} and then nucleating points are introduced.
On the other hand, this tea may simply be tea spilled on the floor, which could then spread out as it evaporated.
|-
| Ironic
| How tea could be ironic is a mystery.
|-
| Segmented
| Tea is usually served in a cup. It tends to stick together and form one liquid. Separating the tea into segments would not be possible without some form of an emulsifying gel.
|-
| Verbose
| This describes using lots of words and language, and would not likely be used for tea, because it cannot speak. Command-line computer programs often run in a 'silent' mode without displaying every step of what happens on the screen. Such programs may have a {{w|Verbose mode|''-verbose'' parameter}} that disables the silent mode. As the replicator is run by a computer, the verbose parameter could be applied to the process of tea-making, with the replicator providing an info-dump on the molecular arrangement of the tea, together with the cup of liquid.
|-
| Cursed
| As with "Blessed", above, items can be Cursed in role-playing games, i.e. having greater negative or lesser positive effects; while there are strategic uses for Cursed items, generally the player would prefer uncursed ones (neutral or blessed). Amongst the curseable items are potions, a class of consumables that do not usually include any teas but does contain the "potion of water", which may therefore be the cause of this cursed cuppa.
Cursed items have featured in xkcd previously: [[2332: Cursed Chair]], [[2376: Curbside]], and [[:Category:Cursed Connectors]].

"Cursed items" are more vaguely defined in real life, making "cursed tea" something rare. However, it is possible for a drink to be [https://www.quora.com/How-do-I-know-if-my-drink-had-a-witchs-hex-potion hexed].
|-
| Unexpected
| By definition, Picard is asking for tea, expecting it promptly. Perhaps the request for it to be "unexpected" would cause it to be delivered at an unknown time in the future, or to have some alteration.
|-
| Bipedal
| Tea does not walk. This would be a very strange term to use when describing tea.
|-
| Afraid
| Tea does not have feelings. Although water {{w|Water memory|may remember things}} (at least pseudo-scientifically) or [https://www.quotes.net/mquote/901305 consider some things to be unpleasant].
|-
| Infinite
| The scope of this request is unclear. It could mean endless production (a steady stream of tea, without obvious limits so long as servicing the request remains practical), an instantaneous production of an infinite volume of tea (possibly more immediately shown to be flawed in its method of execution), or tea which will exceed the heat death of the universe. Either could result in an infinitely ''dense'' tea (eventually?), but this may no longer be {{w|No-hair theorem|identifiable as tea}} so might be one of the less practical options, even amongst those on this list.
Indeed, Randall ranks it as the least 'normal', except for just ''one'' further named order.
|-
| Tea for him, too
| {{w|Earl Grey tea|Earl Grey}} is a tea blend.
Taken along with the title text, this Replicator order is for "Tea" (not otherwise qualified), a replicated version ''of'' the Earl Grey (one or other of those {{w|Earl Grey|of that name}}, possibly the {{w|Charles Grey, 2nd Earl Grey|2nd Earl}} for whom the tea blend was supposedly named) and a second such beverage for him to later drink. See more in the [[#Explanation|explanation]] above regarding the title text
|-
! colspan="2" | Words Picard could have seen in the first drawing, but which were not included as labels on the line
|-
| Cold
| Like Iced tea, asking for cold tea is a relatively normal request.
|-
| Pink
| Earl grey is usually an orange-brown color, not pink. There are, however, a wide variety of [https://www.adagio.com/search/index.html?query=rose teas which come from pink leaves] or [https://www.flourandspiceblog.com/karachi-style-kashmiri-chai-pink-tea/ whose color is "pinkish"].
|}

==Transcript==
:[At the top of the panel, there is a large caption covering two lines with a sub-caption below in a normal-sized font:]
:<big>Other words Captain Picard tried at the end of his tea order before settling on "hot"</big>
:From most normal to least

:[Bellow this we see Picard, drawn bald except for a bit of hair near his ears and behind his head. He stands next to a machine, which is a standing rectangle of the same dimensions as Picard. In the front, there is an opening around the middle, a dispenser from where the ordered items can be retrieved. There is a label at the top of the machine. Picard is giving a command to the machine. His first three words are clearly spoken out as they stand, but then at the end of the sentence, instead of just adding one more word, there is a list of five words in a column between two gray lines. Five words are visible, but the top and bottom words are fading out, presumably other words are above and below, but no longer visible. All except the middle are gray. The middle word is placed as the direct follow up to the first three words in the sentence Picard speaks out, and this word is black like the previous three words. So this middle word is clearly the one he actually speaks out. The others were options, presumably on his mind.]
:Label: Replicator
:Picard:
Good.
Cold.
Tea. Earl Grey. Hot.
Dry.
Pink.

:[To the left of the machine, a long arrow begins snaking its way towards the bottom, where it ends in an arrow pointing down towards the bottom of the panel. At the top, there is a broad and thick bar from which it starts. Beneath this there are several ticks, the first three are close together and on a part of the arrow that goes almost straight down. But then the arrow curves in under the drawing of Picard, and goes over another drawing of him, placed in a captioned frame. The arrow goes around this and up on the other side, where it goes around another drawing of Picard in a similarly captioned frame. After having gone around this frame it goes a bit up before turning almost straight down before the final arrowhead that points down. In total there are 36 labeled ticks on the arrow, see labels below. The ticks have very varying distances between them. There are especially long between them around the first panels with Picard, but closer together at the start and towards the very end. Above the top bar from where the arrow starts there is also a label and just below this and to the left of the long arrow is a smaller arrow pointing down in the direction of the long arrow. This small arrow has a label at its starting point.]
:Bar label: Normal
:Small arrow label: Less normal

:[The second drawing of Picard, shows him standing next to the labeled machine. Picard is this time holding a cup, with sticky lines connecting his hands and the machine to the cup. He clearly looks down at the cup rather than on the machine, as the hair behind his ear is turned differently than the first drawing, where he looks straight towards the machine. Above is a label inside a frame overlaid on the top line of the panel, with what Picard ordered:]
:"Tea. Earl Grey. Sticky."
:Label: Replicator

:[The third drawing of Picard, only displays him and not the machine. He is holding a vibrating cup in both hands and has now turned the other way, away from where the machine was in the previous drawings (again clearly seen by his hair). Very large letters are displayed in three lines behind him to the exclusion of all else. Four of the 15 letters are partly hidden behind the panel's frame, and seven of them are partly covered by Picard. Above is a label inside a frame overlaid on the top line of the panel, with what Picard ordered:]
:"Tea. Earl Grey. Loud."
:Teacup: <big>'''Teeeeeeeeeeeeee'''</big>

:[Words on the arrow from start to finish:]
:Hot
:Iced
:Decaf
:Good
:Lukewarm
:Tasty
:Boiled
:Watery
:Sour
:Meaty
:Solid
:Dry
:Raw
:Deep-fried
:Sticky
:Grilled
:Fossilized
:Magnetic
:Ballistic
:Unstable
:Blessed
:Blurry
:Loud
:Virtual
:Intravenous
:Expanding
:Ironic
:Segmented
:Verbose
:Cursed
:Unexpected
:Bipedal
:Afraid
:Infinite
:Tea for him, too

{{comic discussion}}

[[Category:Star Trek]]
[[Category:Food]]

2552: The Last Molecule

2021-12-09T19:41:46Z

Jmatxx: /* many readers won't understand the original phrase */

{{comic
| number = 2552
| date = December 8, 2021
| title = The Last Molecule
| image = the_last_molecule.png
| titletext = Biology is really struggling; they're barely at 93% and they keep finding more ants.
}}

==Explanation==
{{incomplete|Created by a CONFUSED PARTIAL BIOCHEMIST - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic jokingly proposes a situation in which chemists have discovered and catalogued every single possible molecule. Thus they declare they have "completed chemistry."

In real life the number of ways to arrange atoms into molecules grows combinatorially with the number of atoms in a molecule. Since molecules can be arbitrarily large, the number of possible combinations is much much larger than the number of particles in the observable universe, making the full cataloging of all molecules impossible. Thus, a "final molecule" cannot be reached. In addition, chemistry is the study of the interaction and changing states of atoms and molecules, not simply the cataloging of all specimens of molecule. Even if we did have a list of every molecule, there are a far greater number of ways to continue studying them, so the field would still be nowhere near completed.

This is reminiscent of biology's focus in previous centuries on simply cataloging the species on Earth.

Further, the goal of science is not to "complete" a field, but to understand it better and better. No scientific field is considered fully understood. As readers are aware of this, part of the humor comes from the very high percentages given to the different fields. The title text in particular makes fun of Biology lagging behind due to the inherent difficulty of cataloging all species, when there's no way to know how many new ones remain to be found.

Putting Biology at 93% and Physics at 98% is patently absurd. If biology ''were'' simply a matter of cataloging species, we might be at 10%. As mentioned in the comic, we don't even know how many kinds of ants there are, let alone microscopic organisms. When J.B.S Haldane, founder of the field of population genetics, was asked what could be inferred about the creator from the creation, he reportedly said, "He has an inordinate fondness for beetles". Insects aside, fundamental and important problems such as what genes promote which traits, the nature of cognition, and the mechanism behind several diseases remain complete mysteries. We know less about our own ocean floor than we do about the surface of Mars. Needless to say, Biology is nowhere close to 93% solved. As for Physics, cataloging all particles has been completed with the detection of the {{w|Higgs Boson}} completing the Standard Model. But questions such as "what is dark matter?" and "how do we unify the four fundamental forces?" and "how do we make nuclear fusion possible on earth?" and "how many dimensions does the universe have?" make it clear that the field still has a long, long way to go.

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

:[Ponytail is presenting on a stage. To the top-center of the slide which Ponytail is pointing to, there is a circled "100% complete" under "Chemistry", then to the left is "Biology" which is at "93% complete" and to the right is "Physics" which is at "98% complete". The bottom of the slide shows the [[wikipedia:structural formula|structural formula]] of a molecule which is captioned "The Last One", along with a few smaller captions around it drawn as squiggles.]

:Ponytail: With the discovery of the last molecule, I'm pleased to announce that chemistry is finally complete.
:Ponytail: Best of luck to our competitors in their race for second place.

{{comic discussion}}
[[Category:Comics featuring Ponytail]]
[[Category:Biology]]
[[Category:Chemistry]]
[[Category:Physics]]

2539: Flinch

2021-11-10T19:37:18Z

Jmatxx: /* energy loss -- does not matter that it's "big" */

{{comic
| number = 2539
| date = November 8, 2021
| title = Flinch
| image = flinch.png
| titletext = Premed: "Does this count for a physics credit? Can we shorten the string so I can get it done faster? And can we do one where it hits me in the face? I gotta do a thing for first aid training right after."
}}

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

[[Cueball]] is performing [https://youtu.be/4a0FbQdH3dY?t=1518 a common physics demonstration] in which a heavy ball is hung from a rope or cable. The demonstrator, or a volunteer, pulls the ball back until it's close to their face (possibly even touching it), then releases it, allowing it to swing, and then return. Due to conservation of energy, the ball cannot return any further than its original release point, making it impossible for the person to be struck by it. Because a heavy pendulum will tend to lose little energy on each swing (relative to its overall energy), it will come back very close to its original point, so the experiment creates a conflict between the instinctive desire to escape a heavy object flying at your face, and the theoretical knowledge that it won't harm you.

[[Megan]] is a physicist, who understands the principles of the experiment and claims she won't flinch, confident that it can't harm her.

[[Hairy]] is a biologist, and implies that he has no intention of avoiding the flinch reflex, as he trusts the {{w|Reflex|automatic reflexes}} that the human body has evolved more than he trusts the premise of the experiment. In both [[755: Interdisciplinary]] and [[1670: Laws of Physics]], the same experiment is referenced. In the title text of the latter [[Randall]] makes a very similar argument as the biologist does here.

[[Ponytail]], an engineer, replies that she doesn't trust Cueball to have hung the pendulum correctly. Engineers are trained in science, but work with practical applications, and tend to be very aware that practice is rarely as simple as scientific theories might imply. Even if the physical laws are constant, the experiment might not go according to plan. For example, if the cable were to snap or come loose while swinging toward the subject, the ball could strike them in the body, or land on their feet. If the cable is more elastic than anticipated, it could stretch unpredictably, once again striking someone. If the anchor point is not stable, it could shift during the experiment, once again causing harm. Also if the ball is not released but pushed, or if the one releasing it leans forward after release they might get hit in the face.

The punch line basically makes the point that failure to trust the safety of an experiment doesn't necessarily imply a lack of scientific knowledge. If you lack confidence in the design of an experiment, then it's not safe to assume that the laws of physics will protect you.

The title text shows a pre-med student's response. {{w|Pre-medical}} university courses have a reputation for being more intense and demanding than other undergraduate degrees, so the student is portrayed as being very stressed and time-conscious; showing little interest in the experiment itself, only in how it impacts their degree.

The student first asks if participating in the demonstration will count for a physics credit, implying that they're not willing to spend time on it unless it contributes to their academic requirements. They then ask if they can shorten the string to make the demonstration go faster. Shortening a pendulum does, indeed, cause it to swing faster, but the time saved would be less than the time necessary to make the modification, so the demonstration would not end sooner. Finally, they ask to do a variant where they ''deliberately'' get struck in the face, because they have a "thing for first aid training" immediately after. This would likely injure them, but the student is apparently willing to sacrifice their own safety and well-being in service to their academic career. It's not clear how this would help, although it could potentially help ''others'' learn first aid by having them practice on the new injury.

==Transcript==
:[Cueball holds a bowling ball in both hands. It is attached to a string that goes behind him and up disappearing off panel around double his height. He is talking to Megan, Hairy, and Ponytail who is looking at him. Between Cueball and the other three is a cross in a dotted circle on the floor.]
:Cueball: If you stand with the bowling ball in front of your face and let go, will you flinch when it swings back?

:[Zoom in on Megan in a slim panel. There is a caption in a frame above her.]
:Caption: Physicist
:Megan: I won't flinch.
:Megan: I trust conservation of energy.

:[Zoom in on Hairy, in a wide panel. He has lifted arm holding his hand palm up toward Cueball (who is off-panel). There is a caption in a frame above him.]
:Caption: Biologist
:Hairy: I trust my flinch reflex, which was honed by millions of years of evolution to protect my delicate face. I'm not messing with it.

:[Zoom in on Ponytail in a slim panel. There is a caption in a frame above her.]
:Caption: Engineer
:Ponytail: I don't trust that you hung that thing up correctly.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Hairy]]
[[Category:Comics featuring Ponytail]]
[[Category:Physics]]
[[Category:Biology]]

2525: Air Travel Packing List

2021-10-07T17:39:50Z

Jmatxx: Fixed grammar and typos

{{comic
| number = 2525
| date = October 6, 2021
| title = Air Travel Packing List
| image = air_travel_packing_list.png
| titletext = I know the etiquette is controversial, but I think it's rude when the person in front of me reclines their seat into the bell of my trumpet.
}}

==Explanation==
{{incomplete|Created by an TRUMPETBORNE PARACHUTER - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
This comic is about a proposed air-travel packing list, and the humor is that many people who have not been flying during Covid might have forgotten what to pack. Most of the items are already found on the plane, SOUND like they would be useful on a plane, or could be useful in (the unlikely event of) a plane crash. Here is a quick summary of each:

{| class="wikitable"
! Item
! Explanation
|-
|Seat cushion
|This can be used as a flotation device in a crash and is provided by the airline. Some people may also bring their own cushions for comfort.
|-
|{{w|Parachute}}
|Parachutes are normally used to slow down your falling out of the sky to a relatively safe speed in case of a severe problem with your aircraft, and are routinely used as a safety device by (para)glider pilots, test pilots, military aircraft crew and in similar situations when being unable to land safely is a significant concern. A parachute won't be very useful in a typical passenger airplane (even a small one) as there is no way to safely exit such a plane in-flight. Even the airplanes used to voluntarily exit from while they're perfectly good (as some crazy people do) need to be specifically designed or modified for the purpose such as having wide sliding doors that are unaffected by airflow. However, there were single cases of people being ejected or sucked out of a passenger airplane; in such case a parachute could by arguably useful. Famously, [[:Category:Comics featuring D. B. Cooper|D.B. Cooper]] jumped from an airplane in-flight with a parachute.
|-
|Wing glue
|Probably to repair wings in the event of damage, potentially in a crash. Would be tricky (but not necessarily impossible) to apply mid-flight. This the first of several items that are potentially useful to the flight crew or maintenance teams, but would not be useful or appropriate for passengers to bring aboard.
|-
|{{w|Air horn}}
|An air horn uses compressed air to make a very loud noise very easily. This may be important for drawing attention to yourself in the event of a crash. Typically, emergency lifejackets on a plane are provided with a light and whistle for this purpose. The noise of an air horn might prove more effective for this purpose than a whistle, but it would become useless as soon as the compressed air ran out. Its inclusion is probably meant to suggest that the word 'air' in its name indicates that it's designed for use in an aircraft. Using one in a non-emergency situation would infuriate everyone else on the plane.
|-
|{{w|Sextant}}
|In combination with star charts, a sextant can be used to determine your position based on the location of stars in the night sky. Alternately, in combination with an accurate clock, a sextant can be used to determine the position of the sun relative to the aircraft to determine the vehicle's position. In a crash, you could use this to find your way to a safe place, but sextants are rarely used, and most people not trained on how to operate one. GPS will also allow you to find your position, is built into many phones, and is faster and easier to use than a sextant. If you've got a homing beacon, it probably makes more sense to just activate that and wait for help to arrive. Until the early 1980s, long-range airplanes had a {{w|Air_navigation#Flight_navigator|flight navigator}} who used sextants and {{w|celestial navigation}} to determine the position of the airplane.

Until the early 1980s, long-range airplanes had a {{w|Air_navigation#Flight_navigator|flight navigator}} who used sextants and {{w|celestial navigation}} to determine the position of the airplane. Interestingly, it was much more accurate than early {{w|inertial navigation systems}}, and the accuracy of celestial navigation is still useful today. What made the sextant redundant was the INS' lower workload - the error accumulated by the INS during a long oceanic flight could always and easily be mitigated by other means, for example with {{w|VHF omnidirectional range|VOR}}/{{w|Non-directional beacon|NDB}} radio beacons.
|-
|Nose plugs and goggles for pressure
|Nose plugs and goggles are commonly used in swimming but would be useless for dealing with cabin pressurization or depressurization. Since your mouth and nose are interconnected, nose plugs would be useless on their own. Trying to hold your breath in a sudden depressurization event will cause lung damage, so nose plugs wouldn't be a good thing, even if you could also seal off your mouth. Goggles would also not be useful. During depressurization, the air would just seep out. During pressurization, they would just become uncomfortable and difficult to remove.
|-
|Airplane shoes
|Airlines typically don't require use of special footwear for passengers, nor do they provide special shoes. Before emergency egress, certain shoes (like high heels) must be discarded, though. Air crew are also prohibited from wearing such shoes.
|-
|Navigation crystal
|Mystical form of navigation, presumably either to help with navigating airplane or to help you get home after a crash.
Crystals that polarize light can be used as a compass [http://www.polarization.com/viking/viking.html].
|-
|Spare batteries in case the plane runs out
|Airplanes will generally use more power than any battery small enough to be easily packed in a bag can provide. They will generally use either 115V AC at 400Hz or 28V DC, both of which are very uncommon outside of aviation. The plane will almost never use its own batteries in-flight anyway, getting its electric power from the main engines, the APU, or, in emergencies, the ram air turbine or similar generating device. The batteries are generally only used on the ground when the engines are not running.
|-
|{{w|Birdseed}}
|So one can attract birds. In practice, this wouldn't work for multiple reasons (high speed, altitude and windows being sealed being among most obvious ones) and would pose a significant hazard of birds getting stuck in an engine if it did. On the other hand, spreading birdseed before boarding would be seen as misconduct by airport authorities, as it may pose a danger to aircraft by attracting birds. Alternatively, birdseed can be used to attract birds after surviving a crash, e.g. to catch them for food.
|-
|{{w|Homing beacon}}
|Once activated, a homing beacon will send out a continuous radio signal so that rescuers can find your location. These can be very useful in a plane crash, but airplanes already carry them ({{w|Emergency position-indicating radiobeacon}}s), so you don't need to pack one yourself. Incidentally, the {{w|COSPAS-SARSAT}} system for locating distressed airplanes and ships was a cooperation started by the United States and the Soviet Union, and it was an elegant and simple solution that uses the {{w|Doppler effect}} of radio signals for accurate location - long before the {{w|Global Positioning System}}.
|-
|Meteorite antidote
|Meteorites are pieces of space rocks that make it all the way to the ground. They can cause injury but they aren't poisonous{{Citation needed}}, so an antidote would not help.
|-
|USB wing connector
|This is a just a wire connector, but because it has wing in the name is on the list. Alternatively, the plane wings connect by USB, and this can be used to reattach wings. Airplanes rather use the {{W|ARINC 429}} protocol instead of USB protocols to facilitate electronic communication between flight computers and the engines, for example.
|-
|Emergency siren
|USE IN CASE OF EMERGENCY
|-
|Spare flaps
|Flaps can be moved to adjust the lift/drag ratio of a wing, generally during takeoff and landing. Flaps are very large and mounted on the wing, outside the passenger compartment, so bringing spares would be very difficult and completely useless. Flaps failing to come down can also usually be remedied by just landing at a longer runway.
|-
|{{w|Mouthpiece (brass)|Mouthpiece}} (pandemic restriction; airlines still provide the trumpet)
|A part of a brass instrument like a trumpet. Randall jokes that trumpets are provided on airplanes (which would be very obnoxious to other passengers), but due to the pandemic you cannot use a shared mouthpiece.
|-
|Luggage ballast
|Likely to make plane more balanced. While balancing weight in a plane is indeed a real problem, it's solved by rearranging luggage and adjusting engine power slightly. Introducing ballast would mean additional weight for no real reason.
|-
|Flag (international flights)
|To identify your country of origin. Other flags are also used to communicate between boats without electricity, in the event the boats are in distress, so they could be used in the event of a crash.
|-
|Decoy tickets
|Maybe these would used as a distraction so you can sneak onto the plane without paying.
|-
|Keys to the plane
|Though some pushed for it after a plane was stolen in the {{w|2018 Horizon Air Q400 incident}}, planes do not require keys to activate like a car does. Likewise, plane doors are not locked with a key. Instead, they are rather sealed - if a seal is broken, the plane is thoroughly checked for any wrongdoing.
|}

The title text reference a common debate regarding reclining in airplanes. About half of the people think that reclining is rude as it takes up the space of the person behind. The other half think that seats recline for a reason and the person in a seat has the rights to the space behind them. That has resulted in actual physical fights. Here Randall sides with the anti-recliners, presumably because it would prevent him from playing the trumpet, the person in front will certainly argue that playing the trumpet is annoying, to which Randall could reply that because the trumpet is provided by the airline, he has the right to play it, adding a new layer to the debate.

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

<big>Air Travel Packing List</big>

If you haven't flown in a while, you might not remember what you need to bring. Use this handy checklist to pack!

[Two columns of lists of items. Each item is preceded by a checkbox.]
*Seat cushion
*Parachute
*Wing glue
*Air horn
*Sextant
*Nose plugs and goggles for pressure
*Airplane shoes
*Navigation crystal
*Spare batteries in case the plane runs out
*Birdseed
*Homing beacon
*Meteorite antidote
*USB wing connector
*Emergency siren
*Spare flaps
*Mouthpiece (pandemic restriction; airlines still provide the trumpet)
*Luggage ballast
*Flag (international flights)
*Decoy tickets
*Keys to the plane

{{comic discussion}}