Physics Help Forum equation

 Atomic and Solid State Physics Atomic and Solid State Physics Help Forum

Nov 1st 2018, 03:04 PM   #1
Junior Member

Join Date: Feb 2018
Posts: 6
equation

in attachment
Attached Files
 ea1.doc (37.0 KB, 3 views)

Nov 1st 2018, 06:42 PM   #2

Join Date: Apr 2008
Location: On the dance floor, baby!
Posts: 2,653
 Originally Posted by gab36 in attachment
Just so we don't all have to download the file the question is

If
$\displaystyle \psi (x) = \sum_{q}a_q e^{i q x}$

Then does the Schrodinger equation become:
$\displaystyle \sum_{q'} \left ( \dfrac{\hbar ^2 q'^2}{2m} e^{i q' x} + U e^{i (q' + g) x} + U e^{i (q' - g) x} \right ) a_{q'} = E \sum_{q} a_{q'} e^{i q' x}$

A few points. Why are you using q' instead of just q? Where did the g come from? And finally I'm presuming your potential energy function is U(x) but I can't see how you would have got that form. It should be
$\displaystyle U \psi = U ~ \sum_{q'} a_{q'} e^{i q' x}$

-Dan
__________________
Do not meddle in the affairs of dragons for you are crunchy and taste good with ketchup.

See the forum rules here.

 Nov 2nd 2018, 03:00 AM #3 Senior Member   Join Date: Oct 2017 Location: Glasgow Posts: 362 I think it's just a case of substituting the wave function and processing it with the operators. Have you given it a go?

 Tags equation

 Thread Tools Display Modes Linear Mode

 Similar Physics Forum Discussions Thread Thread Starter Forum Replies Last Post Nforce Quantum Physics 12 Nov 2nd 2018 10:25 AM alexandros87 Thermodynamics and Fluid Mechanics 10 Nov 22nd 2015 03:56 PM pinkprincess08 Thermodynamics and Fluid Mechanics 2 Feb 19th 2014 12:15 PM petdem Thermodynamics and Fluid Mechanics 8 Feb 15th 2010 05:51 AM AAKhan07 Quantum Physics 1 May 28th 2008 02:27 PM