Equal Integration on Real and Rotated Axes: Why the Difference at +pi/4?

[naima]

bonjour,

on http://galileo.phys.virginia.edu/cla...atPhase101.htm
we have the same value on the real axe and on rotated one by-pi/4?
<Note that the result of integration is different wit a rotation of +pi/a (infinity)
regards

 

[HallsofIvy]

Sorry I can't open that page.

 

[naima]

sorry the link is:
http://galileo.phys.virginia.edu/classes/752.mf1i.spring03/StatPhase101.htm
if any prolem you find it on google with the key words: a toy model stationary phase

 

[naima]

of course the question is: why is there an equality when integrating on these axes(real and -pi/4) and why ist it different an the +pi/4 axe?
thanks