# What is the answer to this question in quantum physics? **URL:** \ **Category:** Factual Questions\ **Created:** [October 5, 2015, 4:46pm UTC](https://boards.straightdope.com/t/what-is-the-answer-to-this-question-in-quantum-physics/733624 "2015-10-05T16:46:25Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [October 5, 2015, 4:46pm UTC](https://boards.straightdope.com/t/what-is-the-answer-to-this-question-in-quantum-physics/733624/1 "2015-10-05T16:46:25Z")
See [subject](https://thechive.files.wordpress.com/2015/10/funny-haircuts-barber-say-no-more-5.jpg?quality=100&strip=info&w=1198). How would that be diagrammed by a physicist, as opposed to a barber? ---
**Author:** ![dracoi](https://avatars.discourse-cdn.com/v4/letter/d/90db22/32.png) [@dracoi](https://boards.straightdope.com/u/dracoi)\ **Post date:** [October 5, 2015, 5:24pm UTC](https://boards.straightdope.com/t/what-is-the-answer-to-this-question-in-quantum-physics/733624/2 "2015-10-05T17:24:06Z")
I don’t know about quantum physics, but as a former chemistry major, I think this is the diagram you want: [https://en.wikipedia.org/wiki/Cocaine#/media/File:Kokain\_-\_Cocaine.svg](https://en.wikipedia.org/wiki/Cocaine#/media/File:Kokain_-_Cocaine.svg) ---
**Author:** ![leahcim](https://avatars.discourse-cdn.com/v4/letter/l/b4bc9f/32.png) [@leahcim](https://boards.straightdope.com/u/leahcim)\ **Post date:** [October 5, 2015, 5:50pm UTC](https://boards.straightdope.com/t/what-is-the-answer-to-this-question-in-quantum-physics/733624/3 "2015-10-05T17:50:57Z")
e[sup]i(kx - ωt)[/sup] is the wavefunction of a non-relativistic free particle confined to one spacial dimension. In general, a wavefunction is only determined up to a scalar coefficient, so φ(x,t) and A\*φ(x,t) both represent the same physical system. For bound states, it is conventional to normalize the wavefunction by picking a coefficient such that ∫|φ(x,t)|[sup]2[/sup]dx = 1, which allows with |φ(x,t)|[sup]2[/sup] to be interpreted as the probability of finding the particle at position x at time t. For unbound states (like the one in consideration here), this normalization is impossible, because |φ(x,t)|[sup]2[/sup] is 1 everywhere, which makes ∫|φ(x,t)|[sup]2[/sup]dx = ∫dx infinite, and you can never pick a coefficient to make that zero, so the dude’s request to his barber can’t be fulfilled. The dude’s hair kind of looks like the level curves an unnormalized wavefunction of that form, though. If you squint and take the right projection. ---
**Author:** ![Leo\_Bloom](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/leo_bloom/32/10377_2.png) [@Leo\_Bloom](https://boards.straightdope.com/u/Leo_Bloom)\ **Post date:** [October 5, 2015, 5:57pm UTC](https://boards.straightdope.com/t/what-is-the-answer-to-this-question-in-quantum-physics/733624/4 "2015-10-05T17:57:14Z")
So it’s a trick question! That’s cold. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [October 5, 2015, 6:05pm UTC](https://boards.straightdope.com/t/what-is-the-answer-to-this-question-in-quantum-physics/733624/5 "2015-10-05T18:05:49Z")
> [@Leo\_Bloom](#): > > So it’s a trick question! That’s cold. No, it’s just an problem from the Common Core standardized math exam. ---
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [October 5, 2015, 6:15pm UTC](https://boards.straightdope.com/t/what-is-the-answer-to-this-question-in-quantum-physics/733624/6 "2015-10-05T18:15:35Z")
Common Core doesn’t have standardized math exams. And “an” is used before vowel sounds. You’d probably know that if you paid attention to the Common Core English writing standards. 🙂