Tech & Science dictionary

Schrödinger’s cat

or Schrodinger's cat [shroh-ding-erz kat]

What does Schrödinger's cat mean?

Schrödinger’s cat is a famous physics thought experiment, which presents a paradox in which a cat in a box is somehow simultaneously both alive and dead.

Related words

🐈 - cat emoji , cat tax, cat lady, Grumpy Cat, Nyan Cat, flux capacitor

Where does Schrödinger’s cat come from?

Chris Winsor / Getty Images

Austrian physicist Erwin Schrödinger won the 1933 Nobel Prize in Physics for his work in quantum mechanics, a branch of physics that studies the nature and behavior of subatomic particles. In 1935 Schrödinger came up with a famous thought experiment, now referred to as Schrödinger’s cat, as a criticism of the Copenhagen interpretation of quantum mechanics. The Copenhagen theory stated, essentially, we can’t know what state or place an atomic particle is in until it’s observed, and so that particle could hypothetically be in all possible states or places until then.

Schrödinger found this theory flawed, and to demonstrate why, he asked his colleagues to imagine a “ridiculous case” where a cat, a tiny bit of radioactive material, a Geiger counter, a hammer, and a glass vial of poison were all locked inside a single box. The hammer, the scenario continues, is programmed to smash open the vial of poison—and thus, kill the cat with its fumes—if the Geiger counter detects the radioactive material over the course of the hour. But, the amount of radioactivity is tiny enough that there is a chance the Geiger counter will not pick up on it before the hour is up.

Dhatfield / Wikipedia

Now, if we scale up the Copenhagen theory from the quantum level all the way up Schrödinger’s scenario, then all outcomes simultaneously exist in all possible configurations until one opens the box, which, according to the complex mathematics of quantum mechanics, forces only one outcome: The cat is either alive or dead. The problem is that this would mean that until the very last moment before someone opens the box, the cat is somehow both alive and dead at the same time.

Obviously, a cat can’t be both alive and dead—vampire cats excluded—which was exactly Schrödinger’s point. The Copenhagen theory is a paradox. At what precise moment do the mathematical probabilities give over to physical reality?

Complex scientific theories don’t tend to become online memes, but Schrödinger’s cat is an exception, perhaps due to its rather visceral nature. References to Schrödinger’s cat have been featured in webcomics, images, YouTube videos, in poems, and t-shirts saying that “Schrödinger’s cat is dead” (as some physicists like to joke). The popularity of the LOLcats meme, which depicts house cats in various cute or amusing poses, has also inspired into humorous depictions of Schrödinger’s cat, with many images of cats in cardboard boxes serving as a chance to reference the famous theory. For example, there is an image of a cat angrily clawing its way out of a cardboard box, with the caption “Schrödinger’s cat is alive… and very pissed off.”

On August 12, 2013, which would have marked Erwin Schrödinger’s 126th birthday, Google celebrated by marking its homepage with a cat-themed doodle.

Examples of Schrödinger’s cat

#Physics #Cat will not / Stoop to #Schrodinger's cat jokes / Unless desperate
@quantum_doxie, April 2017
I will save you and the laws of quantum physics all that trouble, and simply show you the Top 12 Schrödinger’s Cat memes.
Jeanne Devon, The Mudflats, August 2013
Neglected friendships are like Schrodinger’s cat: until you check in, they exist as both dead and alive.
Caitlin Welsh, Junkee, April 2017

Who uses Schrödinger’s cat?

While the thought experiment itself is still discussed and taught in schools today, online references to Schrödinger’s cat are often more for the amusement of those who know and appreciate the thought experiment. Often these take the form of cats clawing their way out of cardboard boxes with various allusive captions, but Schrödinger’s cat has also made a lot of appearances in webcomics, which often riff on the complicated nature of quantum theory and its tendencies towards simplification and misinterpretation.

Sometimes, Schrödinger’s cat, or even simply Schrödinger, is used as a way to reference something as a paradox, unfeasible, or working against itself. For example, when India started issuing all its citizens unique 12-digit identity numbers known as Aadhaar, a meme circulated referring to the situation as Schrödinger’s Aadhaar, because the ID system was confusingly presented as both optional and mandatory at the same time.

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