45: Schrodinger

Explain xkcd: It's 'cause you're dumb.
(Redirected from 45)
Jump to: navigation, search
There was no alt-text until you moused over
Title text: There was no alt-text until you moused over

[edit] Explanation

This comic is a joke creating a humorously false synthesis, combining the principals of quantum superposition and the effects of reading a comic one panel at a time.

Schrödinger's cat is a thought experiment that illuminates the notion that a particle only resolves itself to its state upon observation, and until this observation it is in all of its possible states simultaneously. In the thought experiment a cat is both dead and alive until observation, likewise in this comic the comic is both funny and unfunny until the comic is observed (or read).

Black Hat and Cueball are likening the last panel to the box with the cat: until you read it, it is in a mixed state (a superposition) of both funny and unfunny. In the last panel Black Hat says "Shit."

The joke is that after reading the last panel the comic is both funny (as it is unexpected) and not funny (as the last line was a non sequitur and therefore there is no climax) at the same time, thus proving Black Hat and Cueball wrong, hence them expressing discontent with the word shit.

The title text, which Randall here calls the alt-text, suggests that the alt text did not exist until the mouse over action occured.

[edit] Schrödinger's cat

Schrödinger's cat is a famous thought experiment proposed by Erwin Schrödinger to question the Copenhagen interpretation of quantum mechanics.

Under the Copenhagen interpretation, any particle is described by a wave function that allows one to calculate the probability that it is any given state. A radioactive nucleus with a half-life of one hour, for instance, would have a wave-function that would split, showing two distinct states (decayed, undecayed) that change over time until some "observation" forced the wave-function into one state or another (called "collapsing the wave-function"). Before the wave-function is collapsed, it is incorrect to say that the atom has decayed or has not decayed; it is in a "superposition" of states, effectively half-decayed and half-undecayed.

Schrödinger thought the Copenhagen interpretation was absurd, and devised the below thought experiment to show this. The experiment goes as follows: Put a cat in a box, he said, with a device triggered by the decay of an atom with a half-life of one hour that would release a poisonous gas if triggered. Then, after waiting an hour, the Copenhagen interpretation would say that the atom is in a superposition of decayed and undecayed states, and thus, by extension, the cat would be in a superposition of alive and dead states. Only when the box is opened would the wave-function for the cat collapse into either alive or dead states. This thought experiment is not meant to be taken literally as every interaction of a particle with another constitutes a observation, and many particles must interact for a cat to die, but still his argument was that since it is absurd for a cat to be both alive and dead, it is absurd for an atom to be both decayed and undecayed.

If this experiment were to be performed the cat would not be both dead and alive.

[edit] Transcript

[Black Hat and Cueball are standing next to each other. Above them the text is written in a box with shades around it.]
Schrödinger's Comic
[Black Hat and Cueball are still standing next to each other, but Cueball has lifted his arms above his head. The text is again written in a box with shades around it.]
The last panel of this comic is both funny and not funny at the same time.
[Black Hat and Cueball are still standing next to each other, Cueball arms are down again. The text is again written in a box with shades around it.]
Until you read it, there's no way to tell which it will end up being.
[Black Hat and Cueball are still standing next to each other. Cueball has become smaller and smaller through the three frames after the first. Quite clearly here in the last panel. The text is again written in a box with shades around it.]

[edit] Trivia

  • This was the 42nd comic originally posted to LiveJournal.
  • There had been a break of almost a month between this and the previous comic.
    • This time was probably used to prepare the launch of the new xkcd site.
  • Original title: "Drawing: Schrodinger"
    • For the first time in eight comics, and only the second time since after the first day on LiveJournal, is the weekday not part of the title on LiveJournal.
    • But apart from in the very next comic, the extra word "Drawing" was still added to the title for this and the four comics after the next, in spite of the simultaneous release on xkcd.
  • There were no original Randall quote for this comic.
  • This was the first comic to be posted simultaneous (i.e. on the same day) on both LiveJournal and the new xkcd site.
  • This comic was thus one of the last 11 comics posted on LiveJournal.
  • The Schrödinger equation was enhanced by Paul Dirac only three years later in 1928: Dirac equation. It did combine the Schrödinger world with Einstein, e.g. relativity.
  • Black Hat's hat is beginning to shorten from its top-hat look, although its height varies between panels. (As does Cueballs height compared to Black Hat.)

comment.png add a comment! ⋅ Icons-mini-action refresh blue.gif refresh comments!


There were no comments until you scrolled down. 20:21, 1 December 2014 (UTC)

There were two comments before you scrolled down. 12:02, 17 October 2015 (UTC)
Personal tools


It seems you are using noscript, which is stopping our project wonderful ads from working. Explain xkcd uses ads to pay for bandwidth, and we manually approve all our advertisers, and our ads are restricted to unobtrusive images and slow animated GIFs. If you found this site helpful, please consider whitelisting us.

Want to advertise with us, or donate to us with Paypal?