### Why divide h by 4pi?

Posted:

**Wed Oct 16, 2019 1:55 am**What's the purpose of dividing planck's constant by 4pi? What does this tell us?

Created by Dr. Laurence Lavelle

https://lavelle.chem.ucla.edu/forum/

https://lavelle.chem.ucla.edu/forum/viewtopic.php?f=19&t=47682

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Posted: **Wed Oct 16, 2019 1:55 am**

What's the purpose of dividing planck's constant by 4pi? What does this tell us?

Posted: **Wed Oct 16, 2019 9:05 am**

Through experimentation, scientists determined that the minimum uncertainty of knowing both a particles momentum and position simultaneously is this value: h/4pi.

Posted: **Wed Oct 16, 2019 8:19 pm**

Also I think there is a derivation for the equation that would explain why h/4pi is there, but Dr. Lavelle said it was too complicated for us to work through the whole derivation because it uses things we haven't learned yet.

Posted: **Thu Oct 17, 2019 8:41 pm**

The only real way to see why h is divided by 4pi is to prove the entire equation, which is a very long and arduous process. However, if you are interested in it, here is a helpful link showing the proof.

https://www.quora.com/Why-is-h-divided- ... -principle

https://www.quora.com/Why-is-h-divided- ... -principle

Posted: **Fri Oct 18, 2019 11:17 am**

Scientists found out that 4pi is a constant that is consistent whenever using the formula. If you want a more specific answer, Dr. Lavelle said that to discover this we have to fully understand the derivation of the equation which is a long and tedious process since most of the information we haven't learned yet.

Posted: **Fri Oct 18, 2019 11:30 am**

Though I'm not sure about the derivation of this equation/inequality, the essence of what it is trying to convey is that the more we know about momentum, the less we know about position and vice versa. In other words, we must sacrifice one or the other to obtain accuracy in one. Hope this helps!