where i’ve let ħ, c =1

1
) ( 2 1 2 r L t i k t i k r k i e d e d e k d r 2 ) 2 ( ) ( 3 3 where I’ve let ħ,c=1. Recalling that is a function of k, 2 2 m k k it should be primed when k is. Again, I’ve adopted the ħ,c = t i k t i k r k i e d e d e k d i r 2 ) 2 ( ) ( 3 3 i ) ( ) ( ), ( 3 r r i r r write the left-hand side of ) ( 3 3 3 3 2 ) 2 ( 2 ) 2 ( , r k r k i e k d k d i r r ll need to take the Fourier transform of both sides: ) ( 2 ) 2 ( 2 ) 2 ( 3 3 3 3 3 r r e e k d k d i r k i r k i d 3 re iK·r e ik·r d 3 re iK·r I’ve already cancelle 1/(2) 3 from both side over d 3 r introduces a delta function that simplifies the integrati ext do yet ANOTHER Fourier transform: ) ( 2 3 3 3 r r e r d e k d i r i r i K K d 3 r'e iK'·r' e ik·r d 3 r'e iK'·r' Again already cancelin 1/(2) 3 from both side Problem 5-3b Hint You should be able to take it from here, completing the arguments to show ) ( , 3 k k d d k k

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Problem 5-3b Hint. where I’ve let ħ, c =1. †. †. . i. Recalling that  is a function of k ,. it should be primed when k is. Again, I’ve adopted the ħ , c = 1. You should be able to rewrite the left-hand side of in the form:. - PowerPoint PPT Presentation

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Page 1: where I’ve let  ħ, c =1

)(2

1 2 r

L

tik

tik

rki ededekd

r

2)2()(

3

3

where I’ve let ħ,c=1.

Recalling that is a function of k, 22mkk

it should be primed when k is. Again, I’ve adopted the ħ,c = 1.

tik

tik

rki ededekd

ir

2)2()(

3

3†

i

)()(),( 3 rrirr You should be able to rewrite the left-hand side of in the form:

)(3

3

3

3

2)2(2)2(, rkrkie

kdkdirr

You will need to take the Fourier transform of both sides:

)(2)2(2)2(

3

3

3

3

3

rreekdkd

i rkirki

d3reiK·r eik·r d3reiK·r

I’ve already cancelled1/(2)3 from both sides

Integrating over d3r introduces a delta function that simplifies the integration over d3k

Next do yet ANOTHER Fourier transform:

)(2

333

rrerdekd

i riri

KK d3r'eiK'·r' eik·r d3r'eiK'·r'

Again already canceling1/(2)3 from both sides

Problem 5-3b Hint

You should be able to take it from here, completing the arguments to show

)(, 3 kk dd kk