>sci cant even integrate this

it says it right there fucking idiot
>(70.2)

>>8913728
What is this from?

>>8913730
>we must find an theta to satisfy
>an theta

> put it into wolfram
Yes, seems straightforward.

>>8913728

I can't because I can't read this shitty quality image.

File: Capture.png (29KB, 215x247px) Image search: [Google]

29KB, 215x247px

whats this four doing in here?

File: C_3aUG8UIAMQtl6.jpg (158KB, 600x826px) Image search: [Google]

158KB, 600x826px

>>8913766
It looks like the integral over the two-point correlator in quantum field theory. The delta function selects the on shell subspace of non-virtual particles, G is the Green function (correlator), and then there's a wavefunction and its complex conjugate, and an integration measure with physical units.

>>8913728
god bless old timey monographs

>>8913789
Ok, and how would they go about integrating this back before wolfram existed? Would anyone even bother?

>>8913835
>Would anyone even bother?
Calculate scattering amplitudes, decay rates, etc.

>>8913835
First I'd have to see what G was but then I'd probably just use a Gaussian integral table.

>>8913835

Before personal computers you had to buy books with endless tables of approximations.

>>8913766
>>8913789

Feynman's thesis, The Principle of Least Action in Quantum Mechanics

>>8914393
cool

>>8913728
I can't even fucking read it so obviously I can't integrate it. That handwriting is brutal.

>>8913730
lol

>>8913728
anon, no one can even read what the integrand is

>>8913767
Who the hell writes theta like that? I thought it was an g
>an g