Editing 2614: 2

<div style="display: none">crap</div><noinclude>:''This page refers to the comic named "2". For comic #2, see [[2: Petit Trees (sketch)]].''</noinclude>
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{{comic
| number    = 2614
| date      = May 2, 2022
| title     = 2
| image     = 2.png
| titletext = It's like sigma summation notation, except instead of summing the argument over all values of i, you 2 the argument over all values of 2.
}}

==Explanation==
{{incomplete|Created by  A VERY JEALOUS NUMBER ₃½ⁿ₇₇₇ⅥⅣ₆⁸⁴⁴½⅔⅜ↆ↉↉∂, WHO DEMANDS TO HAVE THEIR OWN WEBCOMIC NEXT - Please change this comment when editing this page. The titletext needs to be worked in there, but I think I got everything else in some sort of order, pending general improvements. Do NOT delete this tag too soon.}}

This demonstrates the different ways in which the number 2 can be typeset in various scientific fields.  Whilst these typefaces are used with any number, using the number 2 in this instance provides a clear illustration of where adding numbers can signify either a feature of a concept (such as the number of electrons in an atom) or a mathematical operation on it (such as raising a value to it's second power).

The dotted box represents any character (presumably a letter or bigram of letters). All the other notation consists only of the digit 2, in various fashions with occasional additional punctuation, and labelled as to what the 'purpose' might normally be of any particular element(s) as indicated, with respect to the general term, in the following fashions:
;Regular Math
:Precedes the term. "2x" indicates two times the value of ''x'' in normal {{w|algebra|algebraic}} use that should be familiar for many people. {{Citation needed}}
;Physics
:A preceding superscript. "<sup>2</sup>H" would indicate the particular {{w|isotope}} of Hydrogen with the atomic weight of two, i.e. deuterium, which is most often encountered when working with the atomic level of matter where the total number of neutrons and protons in the atom is important. It can also represent tetration, which is iterated exponentiation.
;Chemical Physics
:A preceding subscript, "<sub>2</sub>He" indicates the atomic number of an atom, which is the number of protons it contains, and thus a guide to the number of electrons its unionised form usually has and hence meaningful in its potential chemical interactions with other atoms. This should be invariant for any particular named element, but is usually given simultaneously with the presuperscripted mass number where it can be indicative of the applicable nuclear physics. {{w|Chemical Physics}} is a subdiscipline of physics and chemistry and **must never** be confused with {{w|Physical Chemistry}}. It can also represent pentation, which is iterated tetration.
;Regular Math or Footnotes
:A trailing superscript is typical of a {{w|Exponentiation|power value}}, in this case "x²" would be ''x'' multiplied by a second copy of itself, and a fairly typical mathematical standard.
:Additionally, superscripted numbers are one common way to mark words in a line of text in a way to refer to a {{w|Note (typography)|footnote}}, typically placed at the bottom of the page, with additional information that would not be appropriate or easily comprehendable to edit into the main text itself. The ambiguity between footnotes and exponents was used in [[1184: Circumference Formula]]
;Chemistry
:A trailing subscript is used in chemistry to indicate a multiple of the element (or group of elements, in brackets) in a {{w|chemical formula}}. "H<sub>2</sub>O" indicates two hydrogen atoms bond with a single oxygen atom in a molecule of water. 
;Matrices! ("2,2")
:Extending the trailing subscript with a comma-separated value usually indicates a multidimensional array (e.g. establishing a 2-by-2 square of numbers, or this particular position in such an array), which is in the realms of {{w|Matrix (mathematics)|matrix mathematics}}. This is a little bit beyond 'everyday algebra' for many people, as seemingly indicated by the exclamation of the mere mention of matrices!
;The Physicists Are At It Again ("2;2")
:This label encompasses a mark that turns the prior comma into a semicolon, as part of the trailing subscript. This is a common notation for the {{w|Covariant derivative}} of a tensor field, which is commonly used in the mathematics of general relativity.
;Either High School Math Function or Incomprehensible Group Theory
:The number 2 in parentheses that follow a term would normally be the argument to a {{w|Function (mathematics)|function}}, e.g. "f(2)", which means that you should take the value (in this case 2) and find the result if manipulated by the predefined function ''f''. It is generally taught as part of algebraic mathematics already described, i.e. at {{w|Secondary school|High School}}.
:In {{w|group theory}}, however, the number 2 in parentheses could indicate a cyclic subgroup or ideal generated by two or a special case of cycle notation for elements of symmetry groups used to mean an element that keeps 2 fixed. This may be somewhat beyond high-school level.{{citation needed}}
;Oh no. Whatever this is, it's cursed.
:A symbol centered underneath another symbol is normally reserved for doing summations, where the big symbol is &Sigma;, or some other operation applied to a sequence of numbers.
:It does not make sense to have a single number there, as indicated in the alt text. As with [[2529: Unsolved Math Problems|other things]] in Randall's comic universe, the explanation for this particular anomaly is that it is 'Cursed'. The usage mentioned in the alt text is an operation (&Sigma;, summation) over a variable usually indicated by a letter such as i, where the operation is performed over all values of the variable, i.e. you &Sigma; the argument over all values of i. In the "2" case, the alt text says you "you 2 the argument over all values of 2", i.e. the &Sigma; operation has been replaced by the "2" operation and the i variable has been replaced by the "2" variable. 2 is usually not an operation, though the definition of 2 under {{w|Church_encoding#Church_numerals|church encoding}} is a function that takes in and produces functions. However, 2 is not a variable (and definitely not both at the same time).
:: Things being cursed is a common trope within recent XKCD comics which have mentioned items including [[2332:_Cursed_Chair|Cursed chairs]] and [[Category:Cursed_Connectors]].  This notation is one of the few occasions where the supernatural have demonstrable implications on science and mathematics for those foolhardy enough to use it.

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

:[An apparent generalisation of a scientific expression consisting of a dotted rectangular 'box' outline, left empty, and various commonly-themed symbology around it:]

:[as normal text, to the left of all the rest:] 2
:[superscript to the immediate left of the box:] 2
:[subscript also to the immediate left of the box:] 2
:[superscript to the immediate right of the box:] 2
:[subscript also to the immediate right of the box:] 2;2 [i.e. separated by a semicolon]
:[as normal text, to the right of almost all the rest:] (2) [i.e. enclosed in standard parentheses]
:[smaller subscript, centered immediately beneath the 2 within the parentheses:] 2


:[Further details are drawn in grey tone, around or near various of the elements of the expression:] 
;[Captions above the numbers]
:[with an arrow pointing to the leftmost 2:] Regular Math
:[with an arrow pointing to the leftwards superscript 2:] Physics
:[with an arrow pointing to the rightwards superscript 2:] Regular math or footnotes
:[with an arrow pointing to the parenthetical 2 at the right:] Either high school math functions or incomprehensible group theory

;[Captions below the numbers]
:[with an arrow pointing to the leftwards subscript 2:] Chemical Physics
:[with an arrow pointing to just the rightwards subscript 2:] Chemistry
:[with an arrow pointing to a distorted grey ring snaking around only the comma of the semicolon and the following 2 of the rightmost subscript:] Matrices!
:[with an arrow pointing to a larger grey ring that passes fully around the whole semicolon and final 2 of the rightmost subscript:] The physicists are at it again
:[with an arrow pointing to the small 2 placed below the parenthetical 2:] Oh no. Whatever this is, it's cursed.

{{comic discussion}}
[[Category:Math]]
[[Category:Physics]]
[[Category:Chemistry]]
[[Category:Comics featuring Cursed Items]]