explain xkcd - User contributions [en]

2731: K-Means Clustering

2023-01-30T19:11:29Z

172.70.134.95: /* Explanation */ n isnt referenced anywhere else, its like creating a new variable and never assigning anything to it, or using it at all. Bruh. ~~~~Bumpf

{{comic
| number = 2731
| date = January 30, 2023
| title = K-Means Clustering
| image = k_means_clustering_2x.png
| imagesize = 320x385px
| noexpand = true
| titletext = According to my especially unsupervised K-means clustering algorithm, there are currently about 8 billion types of people in the world.
}}

==Explanation==
{{incomplete|Created by EITHER 8 BILLION OR 3 TYPES OF BOTS - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

{{w|K-means_clustering|''k''-means clustering}} is a method of categorising vectors into ''k'' clusters. For example, we might categorise a population by two metrics, and want to best categorise this scatter graph into the distinct populations, algorithmically drawing {{w|Voronoi cell}}s to decide the within-cluster variances.

Ponytail's determination that there are three clusters is unsurprising if she herself falls into the category of those who use K=3 as a fixed value, which will inevitably result in three data clusters regardless of actual distribution. The qualitative interpretation of the other two categories — that is, what placement in the other two categories means — is unclear as Ponytail's analysis is either using a binary criterion (whether or not one sorts data into three groups) as the basis for sorting people into three categories, or is a black box using unknown criteria and she has only been able to determine that her own group shares the tendency to group things into threes.

The title text refers to a K-means algorithm with the opposite problem, with no reduction of K value to converge any two human beings into a common cluster based on shared traits. This is humorous because it would make such a clustering useless for the purposes for which a K-Means Clustering is typically used, such as of making insurance risk pools or targets of advertisement campaigns.

Interestingly, by including the entire human population, the algorithm should be immune to bias in creating its input data. However, since every human is unique,{{cn}} the only way to have the clusters converge is to "throw out" some traits of humans as unimportant. This may be objectionable to humans who disagree with that assessment. In contrast, in a supervised algorithm, the training data is tagged with traits that the trainers seek. These traits could be applied in a manner that is socially unacceptable, and lead to AI behavior that reflects the biases of the trainers.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:Ponytail is presenting on a stage, pointing a screen with a stick. The writings and possible figures on the screen are illegible.

:Ponytail: Our analysis shows that there are three kinds of people in the world: Those who use ''k''-means clustering with ''k''=3, and two other types whose qualitative interpretation is unclear.

{{comic discussion}}
[[Category:Comics featuring Ponytail]]
[[Category:Math]]
[[Category:Statistics]]

2723: Outdated Periodic Table

2023-01-11T15:33:14Z

172.70.134.95: /* Explanation */

{{comic
| number = 2723
| date = January 11, 2023
| title = Outdated Periodic Table
| image = outdated_periodic_table_2x.png
| imagesize = 360x350px
| noexpand = true
| titletext = Researchers claim to have synthesized six additional elements in the second row, temporarily named 'pentium' through 'unnilium'.
}}

==Explanation==
{{incomplete|Created HALF AN HOUR AFTER THE CREATION OF EXPLAINXKCD - Please change this comment when editing this page. Do NOT delete this tag too soon.}}
Some elements do not occur naturally on earth and have to be synthesized. Those elements are excluded from the periodic table until they have been synthesized and are no longer theoretical. At the beginning of the universe, the temperature, and thus the kinetic energy, was too high for matter to form big nuclei. It took some time before parts of the universe had cooled down sufficiently for further elements to form naturally. In the first minutes after the big bang only hydrogen, deuterium, helium and lithium nuclei were present. If an imaginary scientific textbook were somehow written back then (note: neither paper nor living organisms existed), it would be able to describe only a very few elements based on observations.

The title text refers to how yet-undiscovered elements are given a [https://en.wikipedia.org/wiki/Systematic_element_name temporary name according to how many protons they have]. Here the numbers are very low ("pentium" being based on "pent" which means "five") because only four elements had been discovered at the time of publication.

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:Figure 6.14
:The periodic table of the elements
:Hydrogen
:Helium
:Lithium
:Beryllium
:You can spot an outdated science textbook by checking the bottom of the periodic table for missing elements. For example, mine was published half an hour after the Big Bang.

{{comic discussion}}

2712: Gravity

2022-12-20T23:57:07Z

172.70.134.95: /* Celestial Bodies */

{{comic
| number = 2712
| date = December 16, 2022
| title = Gravity
| image = gravity_2x.png
| titletext = It's a long way down.
}}

*To experience the interactivity, visit the [http://xkcd.com/2712/ original comic].
==Explanation==
{{incomplete|Created by THE UNIVERSE FROM A PIECE OF FAIRY CAKE- Please continue expanding and describing the various bodies. Do NOT delete this tag too soon.}}
In this interactive comic, the viewer pilots a small spaceship throughout a vast area in space. The viewer is capable of exploring various bodies and planets within the play area, many containing easter eggs alluding to the book What If? 2 and previous xkcd comics. The flight mechanics are largely, if not entirely, Newtonian, so the vessel is capable of using the gravity of planets to alter its trajectory or even enter orbit. The spaceship has indicator circles around it which appear when a gravitational body comes into range, showing the direction towards their center of gravity and the size of the body. A circle also appears around the spaceship whenever it collides with a gravitational body, acting as a shield. The shield remains until the player orients the spaceship upright so its landing gear can deploy.

With a keyboard the arrow keys rotate the spaceship and accelerate it forward and backward. You can also use the standard first person shooter keys 'w', 'a', 's' and 'd', and the standard vi text editor navigation keys 'h', 'j', 'k', and 'l' to control the spaceship. Despite some ships having no unique backward texture, all ships can reverse. On mobile the comic will full screen, pressing either side of the center rotates the spaceship, and pressing in the center accelerates it forward.

It is fairly easy to fly between planets as long as you pay attention to orbital mechanics; don't just floor the accelerator. The background stars show your velocity and orientation relative to the nearest gravity well. If you are having difficulties navigating space, point towards a gravity orb and accelerate for only a few seconds. Wait until the background stars spin wildly, and then reduce your velocity to 0 before gently accelerating towards the object.

'''Playing on mobile:''' Various additional glitches may occur. Having a starting position slightly below the take-off pad means you're already 'glitched' inside the planet from the off. Escaping the planet may need inverted 'accelerating' (turning perpendicular to the local vertical, and thrusting ''backwards'' until you can glitch back out into more open space. You may also be trapped within the cannonball 'orbit', with seemingly inconsistent collision-detection, such that you can be sat ''with landing gear extended'' upon features (projectile tracks, etc) that seem not to count as solid for most other purposes.

There is no "universal" point of view — the bottom of the window, "down", is oriented towards the object exerting the most gravity upon the player. Multiple things found in this comic draw attention to this, such as how on Earth Ponytail says to White Hat, "I checked downforeveryoneorjustme.com and it says just me", and he replies "Yeah, I guess down isn't down for everyone."

Throughout the play area are coins that change the spaceship into different rockets and non-space based vehicles, including humans.

The comic promotes Randall's new book [https://xkcd.com/what-if-2/ What If? 2], which was released in September and is available for purchase. Many of the planets contain references to various What If? articles.

The comic is similar to [[1608: Hoverboard]], which celebrated Thing Explainer instead.

===Celestial Bodies===

The following is an incomplete table of features:

{|class="wikitable sortable"
!
!
!
!
! colspan="4"|References
!
|-
! ID
! Description
! Transcript
! Tiles (X, Y)
! What If
! XKCD
! Movies
! Other
! Explanation
|-
|<code>origin</code>
|'''Starting planet'''
|
Cueball: "To celebrate the world of ''What If? 2'', here is your very own tiny planet to explore!

Megan: "Welcome!"

Ground caption: "Give someone the science question-and-answer book ''What If? 2'' for the Holidays: xkcd.com/whatif2"

Cueball feeding T-Rex: "Burger?"

Isaac Newton: "Robert Hooke must be down there ''somewhere!''"

Megan to Cueball: "If you ever get lost in space, just fly down. That's where the ground is."

Beret Guy to squirrel: "Hi!"
|(0, 0)
|Y
|
|
|Y
|The starting planet. The player begins on the launch pad in a landed position. Collecting the orbiting cannonball will transform you into a different rocket, although it does not improve your abilities.

Cueball feeding the T-Rex is possibly a reference to What If #78: {{what if|78|T-rex Calories}}.

{{w|Isaac Newton}} is referencing the {{w|Newton's cannonball}} thought experiment, where a cannon is fired at greater and greater speeds until the cannonball goes into orbit. Newton's comment suggests that instead of demonstrating orbits, he is firing repeatedly to hit his rival, {{w|Robert Hooke}}.
|-
|<code>earth</code>
|'''Earth'''
|
"How am I supposed to cause the extinction of the dinosaurs if they keep moving out from under my comet?"

"Unusually high-speed squirrels."

"Jump in! The water's fine!"

"Ugh, the frame rate is really bad out today."

"I don't know why people complain about going down rabbit holes. These lil guys are adorable!"

"Ahh, the mysterious natural wonders of sailing stones"

"I'm Bananas Georg.
Every year our company publishes global per capita banana consumption numbers, so to make the printing easier, I eat enough bananas of December 31st to make sure it's a round number."

"Weird, I feel ''heavier''."

"Hey"

"I checked downforeveryoneorjustme.com and it says just me"
"Yeah, I guess down isn't down for everyone"
|(27867,-35648)
|Y
|Y
|
|Y
|A planet with among other things:
* A [https://what-if.xkcd.com/162/ crane dropping a comet] onto a dinosaur,
* Unusually high speed squirrels (creating a sonic boom)
* Megan inviting Cueball into a pool
* A region where the frame rate is intentionally limited
* A flagpole
* A literal {{w|burrow|rabbithole}} referencing the figuratively speaking [[wikt:rabbit hole|rabbit hole]]
* Someone aiming at a satellite with an arrow
* A lake with an eel
* The [https://what-if.xkcd.com/157/ earth-moon firepole]
* A "doot cone," a reference to [[Volcano Types]]
* Two figures being attacked by a third with a sword
* Two kids playing soccer (Catching the ball will turn the ship into a soccer ball)
* A farmer on a tractor being stuck in gooey candy
* A banana pile being consumed by "Bananas Georg" to make the per capita annual banana count round, referencing the "[https://reallyreallyreallytrying.tumblr.com/post/40033025233/average-person-eats-3-spiders-a-year-factoid Spiders Georg]" meme.
* Megan and Cueball digging a hole (in the center of this planet is the "earth's core", referenced below)
* The [https://what-if.xkcd.com/147/ Niagara Falls water being redirected into the LHC] (Large Hadron Collider)
* Japan(?) leaving earth
* A tube to the bottom of the ocean
* Ponytail and White Hat making a reference to [downforeveryoneorjustme.com]
* Two mini asteroid moons: A tiny version of B612 with Little Prince and the rose, plus one with just Cueball standing on it. They can be found by flying straight up from the Super Mario flagpole.
|-
|
|Earth's core
|
| (28850, -28570)
|
|
|
|
|[[Cueball]] and [[Megan]] floating in a small space in the center of the planet in inverted rotations. Can be legally accessed using a high velocity collision onto the surface of the planet, although requires tapping the up arrow afterwards many, many times.
|-
|<code>europa</code>
|'''Europa'''
|
|(13180, -2540)
|Y
|
|
|Y
|Europa, one of Jupiter's many moons (in real life). A broken, icy crust has a single path into its core.
|-
|
|Europa's crust
|
"It's so unfair we don't get to compete in EuroVision."

"The region of the solar system where liquid water can exist on the surface is the habitable zone, and the region where it can exist beneath the surface of moons is the Eurozone."

"WHIRRRR"
|
|Y
|
|
|
|Europa's crust, with a single entrance into the core demarcated by an octopus leaving a hole.
Cueball states that Europa is in the Eurozone, a pun on the ''other'' Eurozone, with liquid underneath its surface.

A roomba whirs across the icy crust.

Cueball has a hairdryer and is melting the surface of the crust. A direct reference to [https://what-if.xkcd.com/35/ What If's Hairdryer].
|-
|
|Europa's core
|"We've always used neutrinos for astronomy, but if we place my 'optical telescope' in orbit above the kryosphere, we could potentially observe the universe using electromagnetic waves. Who knows what else there is out there besides stars! There could be other worlds!"

"Hi, I'm Annie. Welcome to the depths of Europa. There's some weird stuff down here."

"We were caught in a powerful November gale on the Great Lakes outside Whitefish Bay. Our ship foundered and sank here." "This is Jupiter's moon Europa." "It was a REALLY powerful gale."

"Does our book club really need this much secrecy?" "That sounds like a question a SPY would ask."
|
|
|
|
|
|A watery ocean with octopi looking out into the great unknown using telescopes. This is a reference to octopus's intelligence here on earth! It may also be a reference to (Spoilers!) a certain 2013 science-fiction film featuring Europa, if not a 1987 book. There's also a secret path leading to a book club, through the wreck of the Edmund Fitzgerald.

The woman presenting herself as Annie is a reference to Annie Rauwerda, the creator of the popular social media accounts [https://en.wikipedia.org/wiki/Depths_of_Wikipedia Depths of Wikipedia].
|-
|<code>b612</code>
|'''B-612'''
|
Probe: "Asteroid deflection mission to earth. The package is delivered. Commencing planetary threat neutralization."

Sign: "Welcome to B-612"
|(2610,3700)
|y
|Y
|
|Y
|A reference to [[618: Asteroid|Asteroid]]. In a tragic turn of events, the Earth-bound asteroid being blown up is the home of [https://en.wikipedia.org/wiki/The_Little_Prince the little prince].
|-
|<code>dogplanet</code>
|'''Dog park planet'''
|
[Dog Park]

"I want more dogs!"

"Ball! Again!"

"I hope it lands soon."

"English adjective order means that you're "Clifford the Red Big Dog" but not "Clifford the Red Big Dog""[sic]

"You can't have too many dogs!"

|(1240, 11230)
|y
|
|
|
|A planet covered in dogs, along with dog walkers, some fences, and a sign that reads "Dog Park". Two dogs watch a ball which is traveling in what appears to be a circular orbit around the planet. One dog is much larger than anything else on the planet. A hole is being dug by two dogs. Visible at the bottom, there is an empty space in the center of the planet in the shape of a dog bone.
|-
| <code>goodhart</code>
|'''What If? 2 scenario planet'''
|
Cueball to White Hat: "The tower over there is the Vehicle Assembly Building, and then behind it is the Vehicle Disassembly Building."

Ponytail to Cueball: "You know how tires pollute the environment with rubber particles? Well, I've developed a solution."

"MMM SPIDERS HOMF HOMF"

Shooting star caption: "THE MORE YOU KNOW"
Sauropod: "Oh no!"

Person on uncontrolled helicopter: "AAAAAA"

Geyser: "Fwoosh!"
Cueball and Megan: "Oooh!"

Giant phone crushing city: "ALERT" "Giant phone crushing city" "Dismiss" "More"

Cueball with jetpack: "Wheeeee!"

Cueball to Megan: "Do you ever look up at the night sky and think, "Wow, I bet those little white dots taste ''delicious!''"

Neighbor: "Why is my house on fire ''again?!''
Cueball: "Dunno"
Laser captioned: "Laser"

Person with Washington Monument: "Okay, let it drop!"
|(-13300,-3260)
|y
|y
|
| Y
| In aerospace, a Vehicle Assembly Building is where spacecraft are constructed. Randall Munroe whimsically refers to the launchpad as the Vehicle Disassembly Building.

Contains a figure in a cave saying "MMM SPIDERS HOMF NOMF", which refers to [[1268: Alternate Universe|Alternate Universe]] and may also be a reference to the [https://reallyreallyreallytrying.tumblr.com/post/40033025233/average-person-eats-3-spiders-a-year-factoid Spiders Georg] meme.

Collecting the small dot above the mountain peak will turn your ship into a flying person figure.
|-
|<code>sun</code>
|'''The Sun'''
| "The sun is governed by magnetohydrodynamics, or 'Magic' for short"

"My countertop!"

"This will make a good soup base"

"Can I touch it yet?" "No, be patient. It's still too hot. Give it another 20 or 30 billion years."

"It's okay. I'm wearing five layers of sunscreen."

TV Anchor: "The forecast for today is lots of sun"

"This should be enough sunscreen"
|(-14950, 12080)
|y
|
|
|
|Difficult to escape from if you hit the core.
|-
|
|Sun's core
| Cueball: "The core of the sun may seem hot, but it only produces about as much energy per volume as a lizard" Megan: "Wow. So how many lizards are there?" Cueball: "No-one knows."
|
|Y
|
|
|
|Difficult to escape from. Can be escaped by rotating around the sun until an escape-like velocity could be reached.
|-
|<code>soupiter</code>
|'''Soupiter'''
|"I think it's chicken noodle? Hard to tell."
|(-800, -9040)
|Y
|
|
|
|A model of the solar system filled with soup out to the orbit of Jupiter. As commented by Cueball, noodle soup.
|-
|<code>nojapan</code>
|'''Earth without Japan'''
|"Something is missing."
|(-7680, -5850)
|Y
|
|
|
|Earth, except it's missing japan.
|-
|<code>japanmoon</code>
|'''Just Japan'''
|
|(-5930, -5800)
|Y
|
|
|
|A moon with water surrounding... just Japan.
|-
|<code>pigeons</code>
|'''A blob labeled "Pigeons"'''
|
|(-9020, -2490)
|Y
|
|
|
|A reference to Chapter 6 of What If? 2, where it would take 1.6 x 10^25 pigeons to lift you and a chair up to the halfway point of Australia's Q1 skyscraper.
|-
|<code>enterprise</code>
|'''Starship Enterprise'''
|
|(2389, -60879)
|Y
|
|
|
|Star Trek reference: The Enterprise-C, yes 2344,commanded by Captain Garrett's. While defending a Klingon outpost, the weapons discharges resulted in the creation of a temporal rift, through which the badly damaged Enterprise drifted. In the comic, there is a large, invisible gravity distortion near the Enterprise-C
|-
|<code>qwantz</code>
|'''Dinosaur planet'''
|"Welcome... to Jurassic Park."
| (20403,-49559)
|
|
|Y
|
|An homage to [https://www.qwantz.com/ Dinosaur Comics], a webcomic Randall has mentioned several times before. All the dinosaurs on the planet are black-and-white versions of the clip art dinosaurs in that comic. Also references the Jurassic Park movies, with CEO John Hammond welcoming paleontologists Dr. Sattler and Dr. Grant to the planet. The long grass depicted is a plot point in later films.<br><br>It seems like crashing into this planet hard enough will let you dive into the core, but that only lets you out on the other side. Then the system seems to glitch and have the ship phase into and out of the planet.
|-
|
|'''What If? 1 scenario planet'''
|
|
|
|
|
|
|
|-
|<code>roads</code>
|'''Cat blocking traffic flowing through portals'''
|
|
|
|
|
|
|
|-
|<code>outside</code>
|'''Edge of the Universe'''
|"Welcome, traveler!" (found inside the edge of the bubble universe)
| ( 6081, 26138 )
|
|
|
|
|It looks like a planet labeled "edge of the universe". Outside the universe, so inside the "edge of the universe" planet, is another universe, the bubble universe, whose outside is labeled "edge of the bubble universe". Hidden entrance is between 10 and 11 'o clock. It is a reference to [[Bubble Universes]].
|-
|<code>roads</code>
|'''A tree larger than the planet it's growing on'''
|
|
|
|Y
|
|
|May be a reference to [[2: Petit Trees (sketch)|Petit Trees]]. More probably, a reference to ''The Little Prince'', a French children's novel about a traveler from a distant asteroid. In the novel, baobab trees are a serious threat to the Prince's home asteroid, as they are so large that their roots would engulf the asteroid entirely. Randall has alluded to The Little Prince numerous times before, especially in what-if articles.
|-
|<code>outside</code>
|'''Milliways'''
|
| in code: <code>[0,-14500]</code><br>in game: <code>[0,29000]</code>
|
|
|Y
|Y
|A reference to Milliways, the Restaurant at the End of the Universe from ''The Hitchhiker's Guide to the Galaxy''. On one side of the planet, Ponytail, Cueball, Megan, and other characters gather on the patio of the Milliways restaurant; on the other side, the Sojourner rover examines a rock.
|-
|<code>greatattractor</code>
|'''The Great Attractor'''
|
|(-596048, 247952)
|
|Y
|
|
|Beret Guy stands on the surface of a large ball labeled "The Great Attractor". The gravity is extremely strong (over 200 times that of the black holes), leading to various bugs and collision issues. It's a reference to [[Great Attractor]], in which Beret Guy is gravitationally attracted to the Great Attractor more strongly than usual.
|-
|<code>present</code>
|'''Present'''
|
"I didn't do any of my Christmas shopping yet because I was too busy drawing tiny planets."

"I'm done with my shopping! I got everyone What if? 2"

"...You got me my own book?"

"Yeah! I figured that since you wrote it, it must be right up your alley."

"It does make a good gift, though. You can get it at xkcd.com/whatif2"

"I got you this present!"

"Is it an angry bobcat?"

"It might not be."
|in code: <code>[22820,-18920]</code><br>in game: <code>[45640,37840]</code>
|
|Y
|
|
|The XKCD cast react to giving each other What if 2? as a present. Black Hat gives Cueball a "gift" which he claims "might not be a bobcat", a reference to [[A-Minus-Minus]] A quarter of the planet was missing on the release day, but it's fixed now.
|-
|<code>maw1</code>, <code>maw2</code>, ... <code>maw14</code>
|'''Black hole cluster'''
|
|
|
|
|
|
|A cluster of black holes with extremely high gravitational strength, set to the maximum of 2048. Not particularly easy to land on with multiple conflicting gravitational fields, but once landed on, rather difficult to escape. Likely a reference to the [https://starwars.fandom.com/wiki/Maw_Cluster Maw Cluster] in Star Wars.
|-
|<code>remnant</code>
|'''Remnant'''
|"All right, that's close enough"
"Oh no"

{{w|Walkin' on the Sun|"So don't delay, act now, supplies are running out"}}

"In 5 billion years, the Sun will run out of fuel and suffer gigennial burnout."

"The immense gravity of the sun's remnant means that this is the tallest possible skyscraper."
|(19620, 3800)
|
|
|
|
|A stellar remnant, with high gravity (making it difficult to escape, although it's possible to achieve escape velocity by flying sideways). Has various small landmarks, including a "skyscraper" and suspension bridge. There is a set of images of a rocket descending towards the planet, falling and then trying to escape by sledding.
|-
|<code>steerswoman</code>
|'''Steerswoman Planet'''
|"As a Steerswoman, I have to answer any question anyone asks me, or I'm expelled from the order."
"What's one question that you would be unwilling to answer?"
"Oh no."

"Handle this artifact with great care. It contains a magical wizard's potion which the ancients called 'trinitrotoluene'"
|(-35070,-2500)
|
|
|
|Y
|A reference to the Steerswoman series of books by Rosemary Kirstein. Includes a number of references to the series, including a group of people observing a small object orbiting the planet.

Trinitrotoluene is better known as {{w|TNT}}, a powerful explosive.
|-
|<code>peeler</code>
|'''Peeler'''
|
|(-9270, 620)
|Y
|
|
|
|A reference to the question posed by "What If 2: Lose Weight the Slow and Incredibly Difficult Way". A large potato peeler is seen removing the earth's crust.
|}

===Ships===
{|class="wikitable sortable"
|-
! Name
! Description
! Location
! Filename
! Image
|-
|Default
|The starting ship.
|It is possible to change back to this ship by collecting a dot located within the Black Hole cluster
|ship2
|
|-
| Tintin
| Ship in the shape of the [https://en.wikipedia.org/wiki/Destination_Moon_(comics) moon rocket from Tintin]
| On the starting planet; can be obtained by collecting the cannonball in orbit
| ship-tintin
|
|-
| Figure
|Stick figure
|On Goodhart, atop the mountain up which Sisyphus is pushing his boulder.
|ship-figure
|
|-
| Soccer ball
| Soccer ball shaped ship
| On Earth, between two figures playing ball
|ship-soccer
|
|-
|Alternative Ship
|Slightly thicker version of default ship
|Only available by using console to change Comic.ship
|ship1
|}

==Data and Maps==

View the data that is embedded in the comic on [[2712: Gravity/Data|this page]].

Maps created by the Community:
*https://bacontime.github.io/xkcd2712 | A zoomable map of the universe with markers for all planets, coins and with the option to highlight secret passages
*https://www.reddit.com/r/xkcd/comments/zpe7bz/i_rendered_the_entire_what_if_2_universe_as_a/ | The whole universe rendered as one big image

==Hacks==
Various modes and hacks have been found or developed by the community, and can be activated by opening the Javascript Console (F12 [Or Command-Alt-I in most browsers under Mac OS X] to open Developer Tools, then Console tab) and writing corresponding commands.<br>
'''Click to expand:'''<br>

<div class="mw-collapsible mw-collapsed leftAlign" style="width:100%">
<br>
*'''Speedhack:''' <code>ship.engines = "warp"</code> - Speed hacking, sets speed to 1.4x. set to "standard" to reset to normal speed
*'''Teleport to planet:''' <code>[Comic.voyager.pos.x, Comic.voyager.pos.y] = Comic.planetRects.'''''origin'''''.slice(0,2)</code> - teleport near a planet, in this example near earth. You'll still have to fly a bit towards the nearest planet to reach it. Replace '''''origin''''' with the ID of the planet you want to go to, from the table above.
*'''Teleport to coordinate:''' <code>[Comic.voyager.pos.x, Comic.voyager.pos.y] = '''''[0, -2000]'''''</code> - teleport to an exact coordinate. <code>[0, -2000]</code> happens to take you to the starting area.
*'''Improved radar:''' <code>Comic.wayfinderFarDistance = Infinity</code> - make the direction of all objects visible. This can be hard to understand though.
*'''Chaos Mode:''' <code>ship.engines="infinite improbability drive"</code> - Seems to randomly teleports the ship. A reference to its namesake in Hitchhiker's Guide to the Galaxy.
*'''Insta Death:''' <code>ship.shields = false</code> - Kill the player if they land on a planet, the code never sets it to false, so it seems to be always true.
*'''No Clip:''' <code>noclip = true</code> - Enables noclip. Also disables gravity.
*'''Select ship:''' <code>Comic.ship = "ship-tintin"</code> - Select ship (use filename from list of ships)
*'''Autorotate:''' <code>Comic.cameraRotation = false</code> - View does not rotate with ship
*'''Goggles:''' <code>ze.goggles()</code> - returns a warning: "they do nothing!". This is a reference to Hoverboard, where ''ze.goggles()'' would give you the ability to see false walls. Which itself is most likely a reference to the Simpsons where Radioactive man complains that his safety goggles do nothing against a deluge of acid.
*'''Python:''' <code>python("import antigravity")</code> - reverses gravity, so the ship falls away from planets. A reference to [[353: Python|Python]]. Reset with <code>Comic.gravityConstant = 100</code>. Also a reference to 353: Python.
*'''Light Mode''' <code>("Comic.lightMode = true")</code> - inverts the color of the comic. reset with <code>("Comic.lightMode = false")</code>
</div>
<br>

==Trivia==
The objects in the mini-universe of this browser game are all at fixed positions and do not interact through gravity, however, the ship controlled by the player is affected by gravity. While this makes it technically a relatively easy integration problem (of the position of the player ship forward in time), the integrator used seems to be a relatively simple one - and certainly not a symplectic one, because it does not conserve angular momentum. This can be seen when one manages to get into orbit around some object, e.g. the core of the sun. The orbit slowly decays over time.

The logic for extending the landing legs and landing is rather simple. A ship can (normally) land if it is facing away from the surface it collides with, and if its momentum is more-or-less directed towards the surface. Once landing is triggered, the ship will rotate to face directly away from the celestial body it is on, regardless of how sloped the surface is. The only way to get into space again is to accelerate forwards, as neither turning nor accelerating backwards cancels the landed state. All of this can be abused to land on almost everything. To land on the underside of an object, simply point your ship away from the object and slowly accelerate backwards to counteract the force of gravity. Landing on the side of an object is more difficult, as ships cannot accelerate sideways. The first method is to accelerate backwards to launch yourself upwards and towards the object so that at the top of your arc you will collide with the object. Then, rotate your ship accordingly to land. Method two is to just repeatedly slam your back of your ship into the object until you land. Note that with any of these weird landing methods, your ship will turn to face away from the source of gravity and can clip into objects.

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

Welcome!

To celebrate the world of what if? 2, here is your very own planet to explore!

Give someone the science question-and-answer book what if? 2 for Christmas:
xkcd.com/whatif2

{{comic discussion}}
[[Category:Space]]
[[Category:Book promotion]]
[[Category:Interactive comics]]
[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Megan]]
[[Category:Comics featuring Black Hat]]
[[Category:Bobcats]]

2667: First Internet Interaction

2022-09-03T20:12:55Z

172.70.134.95: /* Explanation */ This doesn't make any sense. It's almost certainly not what Randall was going for, and the last sentence spells out why it doesn't work in context at all. Just because his sentence is cut off doesn't mean that autocorrect is relevant

{{comic
| number = 2667
| date = September 2, 2022
| title = First Internet Interaction
| image = first_internet_interaction.png
| titletext = To that stranger on the KOOL Tree House chat room, I gotta hand it to you: You were, ultimately, not wrong.
}}

==Explanation==
{{incomplete|Created by AN AMERICAN IDIOT - Please change this comment when editing this page. Do NOT delete this tag too soon.}}

In this comic, [[Cueball]], very likely as an autobiographical representation of [[Randall]], describes to [[Megan]] the first time he interacted with a group of people unknown to him over the internet; in an {{w|AOL|AOL}} chat room for children called the "KOOL Tree House chat room" in 1993, when Randall was about nine years old. He read a discussion about {{w|Green Day}}, asked who they are, and was told that not knowing was a serious problem. As Megan says, judging people for lack of pop culture knowledge has remained typical online behavior.

Green Day is an American rock band formed in the East Bay of California in 1987. In 1993, they were still known merely as an independent punk band, and a year away from releasing their major-label debut album ''{{w|Dookie}}'', their first mainstream success. Anyone, especially a nine year-old, not recognizing the band in 1993 would be perfectly normal. After 1993, Green Day would go on to be a widely popular and influential rock band with many acclaimed albums.

This initial online social interaction was a significant formative experience for Cueball, molding his online behavior ever since, in that it still causes him to consider his correspondents' perspectives when communicating. The social dynamics at play are reminiscent of the mathematics of others' perspectives described in [[1053: Ten Thousand]]. Relating the personal experience of an oversized effect from a casual insult is humorous, because the extent to which early experiences affect people can be both ironic and profound.

The title text indicates Randall agrees with the reply to the question, suggesting he believes the band is important culturally. Randall probably subsequently became a Green Day fan, or at least acquired more than a passing knowledge of their {{w|œuvre}}, recently mentioning their song "{{w|American Idiot (song)|American Idiot}}" in [[2665: America Songs]].

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
:[Four panels depicting a conversation between Megan and Cueball]

:[First panel, Megan and Cueball talking]
:Cueball: You know,
:Cueball: I remember the first thing anybody ever said to me on the internet.
:Megan: Yeah?

:[Second panel, part-height to accomodate Cueball's narration above and the memory of a scene below that features 'Young Cueball', with a mop-head of hair, knelt atop a chair to use a computer with CRT and keyboard on the desk, cabled down into a floor-standing minitower case below]
:Cueball (narrative): I was in an AOL Kids chat room in 1993.
:Cueball (narrative): People there kept using a name I didn't recognise.
:Cueball (narrative): After a while I asked what it was.
:Young Cueball (via the use of the keyboard): W... H... O...  I... S...  G... R...

:[Third panel, close-up of Cueball's adult head, continuing the framing conversation]
:Cueball: Someone replied.
:Cueball: "If you don't know who Green Day is, you have a serious problem."
:Cueball: And that was it. My first virtual interaction.

:[Fourth panel, continuing the conversation, Megan and Cueball now seen walking rightwards as they speak]
:Megan: In some ways, the Internet has changed surprisingly little in the last 30 years.
:Cueball: Every time I reply to someone, I think
:Cueball: What if this is their Green Day moment?

{{comic discussion}}
[[Category:Comics featuring Cueball]] 


[[Category:Comics featuring Megan]]

Talk:2666: Universe Price Tiers

2022-09-01T15:59:08Z

172.70.134.95:

We seem to be in Universe Standard, based on the cosmic speed limit
[[User:Victor|Victor]] ([[User talk:Victor|talk]]) 22:03, 31 August 2022 (UTC)

Is the price per user (human)? Or payed by the "god" who runs the universe?
The interpretation would change quite a bit. If per user, some could travel fast while others would not see ads and could even be immortal.
If per universe, would the concept of ads disappear?
[[User:Victor|Victor]] ([[User talk:Victor|talk]]) 22:25, 31 August 2022 (UTC)

General comment, I think each line of the table should have a separate one-line or one-paragraph explanation, rather than squishing it into one column of a table which mostly reproduces the comic text. i.e. we don't need the table in the explanation, although it works fine in the transcript imo. [[Special:Contributions/172.69.62.71|172.69.62.71]] 23:40, 31 August 2022 (UTC)edit: a word

"Yes, and he cheats" may be a reference to a quote from ''Sid Meier's Alpha Centauri''.
::I fully expected something like ''"Most gods throw dice, but Fate plays chess, and you don't find out 'til too late that he's been playing with two queens all along."'' (from ''Interesting Times'' by Terry Pratchett) [[User:RAGBRAIvet|RAGBRAIvet]] ([[User talk:RAGBRAIvet|talk]]) 01:47, 1 September 2022 (UTC)
::The SMAC quote is "Einstein would turn over in his grave. Not only does God play dice, the dice are loaded. - Chairman Sheng-ji Yang", from the Probability Mechanics tech. Also, the "God does not play dice" quote is stated during the Supercollider secret project movie. I doubt the comic is referencing any particular media here, though. [[Special:Contributions/172.69.22.5|172.69.22.5]] 02:40, 1 September 2022 (UTC)

Under ''Number of angels that can dance on the head of a pin'', '64' is 2⁵ and may be making reference to the Nintendo 64 game system. [[User:RAGBRAIvet|RAGBRAIvet]] ([[User talk:RAGBRAIvet|talk]]) 01:54, 1 September 2022 (UTC)
::And just for the record, 4096 is 2¹². [[User:RAGBRAIvet|RAGBRAIvet]] ([[User talk:RAGBRAIvet|talk]])
Who is paying our subscription? How do we ensure we don't get demoted to lite?

Here, the sound of one hand clapping is pretty much "toop." Put your hand out flat fingers together, and no thumb involved, quickly make a fist. Toop. [[Special:Contributions/172.70.134.95|172.70.134.95]] 15:59, 1 September 2022 (UTC)

2666: Universe Price Tiers

2022-09-01T12:41:52Z

172.70.134.95: /* Explanation */

{{comic
| number = 2666
| date = August 31, 2022
| title = Universe Price Tiers
| image = universe_price_tiers.png
| titletext = In Universe Pro®™ the laws of physics remain unchanged under time reversal, to maintain backward compatibility.
}}

==Explanation==
{{incomplete|Created by a SOWN WIND - Explained the main point, more details needed. Please change this comment when editing the page . Do NOT delete this tag too soon.}}
Philosophers have posed many questions in trying to understand the nature of the universe. Some of these have become well-known in popular culture; while some are deliberately open-ended, several others are presented as a choice between two or more options, and are assumed to have a single answer, the debate being about which is correct. In this comic, Randall proposes that the answers to these questions are instead not fixed, but vary according to a tiered {{w|subscription business model}}, as seen in many business pricing schemes, particularly in software. In this model, the no-cost tier gets you a universe experience of a lower quality, while at higher tiers better options are available for a cost - for example in the highest tier the processes of aging and death are "Opt-in" rather than "Mandatory". It is not clear from the comic who is supposed to be paying these subscription fees, or whose experience of the universe is supposed to be affected.

The universe does not have a subscription model,{{citation needed}} but on the chart some of the categories that refer to observable properties such as the speed limit or existence of the {{w|Uncertainty Principle}} indicate ours is the Universe Standard® subscription, but other specifications may not entirely match our user experience.

The title text refers to the concept of {{w|T-symmetry}} in physical laws. Most properties of our universe are asymmetric, meaning that the property changes if time is reversed (e.g. the entropy of the universe decreases as time flows backwards). Randall again makes a reference to software subscription models in a play on words as the Universe Pro®™ sub appears to have laws that maintain "backwards compatibility".

{| class="wikitable"
|-
! !! Universe Lite™ !! Universe Standard® !! Universe Pro®™!!Explanation
|-
! Price
| Free || $14.95/month || $49.95/month || Indicative of a typical Freemium product, the versions released include what is effectively an 'unlimited trial' version, but lacking some potentially desired features, and then extra tiers with increased functionality so that you can "get what you pay for".
|-
! Ads
| Yes || Yes || No || There are indeed ads in our own universe, but whether they are an intrinsic property of the universe or not is an open question.
|-
! Number of angels that can dance on the head of a pin
| 4 || 64 || 4,096 || "{{w|How many angels can dance on the head of a pin?}}" is a question used to poke fun at medieval angelology and medieval scholasticism in general by claiming discussions in its fields revolve around meaningless questions. It is also used as a metaphor for wasting time debating useless questions, as it is generally accepted that we can have no definititive answer. Here, the question is given concrete answers that are powers of 2 often seen when using binary representation. It may also be a reference to [[485: Depth]].
|-
! Free will or determinism
| Determinism || Free will || Free will || Another predominantly philosophical issue, although physics (both Newtonian and Quantum) has not shied away from trying to answer this (see Does God Play Dice? below). It is interesting that the paid versions of the universe are the only ones to include free will, implying that either such a quality is inherently desirable or it is a necessary condition of some other feature in the paid plan (such as, for instance, the aforementioned dice-playing).
|-
! Cosmic speed limit
| 65 mph || 300,000 km/s || Unlimited || The Cosmic speed limit refers to the {{w|speed of light}}, which rounds to 300,000 kilometers per second in our particular universe, one of the few definite clues as to which tier we might exist in. Living in a universe with such a low speed limit would render many aspects of experience unrecognizable from our own; assuming the speed of light and thus all relativistic effects were similarly scaled, the act of driving at highway speeds would result in [http://gamelab.mit.edu/games/a-slower-speed-of-light/ human-observable] time dilation and apparent spatial distortion. The idea of having a speed cap is reminiscent of computer simulations and game engines, which often prevent agents from accelerating beyond a certain point to prevent unintended behavior.
|-
! If a tree falls in a forest and there's no one there to hear...
| No sound || Simple beep || Full sound || {{w|If a tree falls in a forest}} is a popular philosophical question whose answer depends largely on one's philosophical belief system and the interpretation of the question itself. Here it's suggested that there is a definite answer which differs depending on the quality of the universe subscription. On the assumption that "our" universe is on the Standard Plan, this table implies that all trees falling outside of the auditory range of anyone or anything capable of noticing it emit a simplified "beep" sound, rather than the complex crashing one would expect. Given loose enough assumptions, we cannot "prove" in a classical sense that this is not the case, and this may contribute to the humor of this entry.
|-
! Meaning of Life
| Unknowable || Uncertain || Clearly explained || All we can know is that we (currently) don't know, which makes our universe one almost certainly either with an unknowable or uncertain state of affairs.{{Actual citation needed}}
|-
! Sound of one hand clapping
| [None] || [None] || ''Kazzap!'' || A {{w|Koan}} from Buddhism. Koans deliberately have no answer — one hand cannot clap, as the sound of two hands clapping relies upon there being two hands percussing and displacing/resonating air. The "Kazzap" referenced is humorous because it provides an answer to something with no answer, in the form of a nonsense onomatopoeia. To members of our universe, this is absurd. The implication is that those in the Pro version of the universe have access to this seemingly impossible feat.
|-
! Aging and death
| Mandatory || Mandatory || Opt-in || If this is a mere option, we clearly haven't read (or understood) the online manual or perhaps read the tool-tips.
|-
! Does god play dice with the universe?
| Yes, and he cheats || Yes || No || A reference to a phrase famously ascribed to Einstein (in opposition to the concept of quantum uncertainty) that "God does not play dice with the universe." This option and the Determinism/Free Will choice, above, are interestingly linked but not necessarily in a way we can comprehend.
|-
! Bad things...
| Happen to good people only || Happen to good and bad people || Don't happen || Relates to whether there is justice, compassion or fairness in the universe, or perhaps if there specifically is not. In theological arguments, this debate is intimately connected with theodicy (the "problem of evil"), but like the existence of free will it is hotly debated in non-theological contexts as well.
|-
! What happens to those who sow the wind
| Reap the whirlwind || Reap the whirlwind || Lots of crops everywhere ||  This is a reference to the famous phrase "sow the wind, reap the whirlwind", taken from Hosea 8:7. The phrase means that those who do evil without thought to the consequences will receive punishment. However, in Universe Pro®™, where nothing bad happens to anyone, acting rashly results in a tremendous crop yield.
|}

==Transcript==
{{incomplete transcript|Do NOT delete this tag too soon.}}
{| class="wikitable"
|-
! !! Universe Lite™ !! Universe Standard® !! Universe Pro®™
|-
! Price
| Free || $14.95/month || $49.95/month
|-
! Ads
| Yes || Yes || No
|-
! Number of angels that can dance on the head of a pin
| 4 || 64 || 4,096
|-
! Free will or determinism
| Determinism || Free will || Free will
|-
! Cosmic speed limit
| 65mph || 300,000 km/s || Unlimited
|-
! If a tree falls in a forest and there's no one there to hear...
| No sound || Simple beep || Full sound
|-
! Meaning of Life
| Unknowable || Uncertain || Clearly explained
|-
! Sound of one hand clapping
| [None] || [None] || ''Kazzap!''
|-
! Aging and death
| Mandatory || Mandatory || Opt-in
|-
! Does god play dice with the universe?
| Yes, and he cheats || Yes || No
|-
! Bad things...
| Happen to good people only || Happen to good and bad people || Don't happen
|-
! What happens to those who sow the wind
| Reap the whirlwind || Reap the whirlwind || Lots of crops everywhere
|}
{{comic discussion}}
[[Category: Philosophy]]
[[Category: Religion]]

Talk:2628: Motion Blur

2022-06-04T20:00:55Z

172.70.134.95:

Personally, I'm animated on twos but make up for it with good smear frames. [[Special:Contributions/172.70.135.98|172.70.135.98]] 14:07, 4 June 2022 (UTC)

== Randall has got this issue backwards: ==
Too *low* a framerate causes choppiness when panning (or on objects in motion). ''Too low'' a framerate causes the human eye to perceive multiple images of a mouse cursor; a higher framerate can exceed the perceptual latency of human vision, causing the moving cursor to be perceived as a continuous blur, whereas a lower framerate merely exacerbates the issue of seeing the cursor jump from position to position.

To that point, the current explanation exemplifies this confusion, also getting it backward: ''"If the shutter speed is too high, this blurring will not occur, and the motion will look unnaturally crisp – if something is too small and/or too quick, the illusion of motion may disappear altogether; the object instead will appear as a brief flash of multiple objects standing still,"~'' '''This is incorrect.''' Human visual blur is ''not'' dependent on the displayed frames being blurred: With panning in high framerate video, unblurred footage ''appears blurred'' to the human eye, due to persistence of vision; whereas with low framerate video we may ''not'' perceive blurred motion & instead view each frame individually & perceive it as choppy.

Point being, you need a framerate ''at least as high as 60 FPS'' to avoid choppy appearance when panning, & for some people's vision the minimum framerate to ensure motion blur is 100 FPS. 24 FPS is used in cinema ''to preserve the choppy look of old 24 FPS film projection'', as an aesthetic choice.

Higher framerates look ''less'' choppy. ''Low'' framerates are what appears choppy when viewed.
[[User:ProphetZarquon|ProphetZarquon]] ([[User talk:ProphetZarquon|talk]]) 14:10, 4 June 2022 (UTC)

:Yes, at high framerates, ''when the subject is perfectly sharp'', the blurring is done by human vision. At lower framerates, this natural blurring is mostly lost, and this effect must be counteracted by correspondingly lower shutter speeds so that motion appears blurry again. That's the whole point of the comic. [[User:Kapostamas|Kapostamas]] ([[User talk:Kapostamas|talk]]) 14:30, 4 June 2022 (UTC)

:: Exactly. Film typically has 24 FPS, animation is typically produced at 12 FPS, and 8 FPS is common in anime, and to make up for it by introducing the illusion of motion in other ways. With physical cameras that usually means low(ish) shutter speed to creating in-camera motion blur. [[Special:Contributions/172.70.134.95|172.70.134.95]] 20:00, 4 June 2022 (UTC)

In order to explain this, and prove that the explanation is correct (or prove that Randall is either correct or incorrect), there needs to be a link to two videos showing the error and the corrected version without the error. In other words, citation needed. [[Special:Contributions/172.70.126.65|172.70.126.65]] 15:35, 4 June 2022 (UTC)

:How's this: [https://youtu.be/i9bv00ZA-ao]? [[User:Kapostamas|Kapostamas]] ([[User talk:Kapostamas|talk]]) 16:47, 4 June 2022 (UTC)

Talk:2627: Types of Scopes

2022-06-01T17:23:30Z

172.70.134.95: /* What's with all the vandalism‽ */ :/

== What's with all the vandalism‽ ==

I get this is the internet and therefore there will be some vandalism, but YIKES! What happened to this post? Why does it have so much more vandalism than usual‽ {{unsigned|SqueakSquawk4}}