[FOM] Question about theoretical physics

[Arnold Neumaier]

On 03/01/2013 07:22 AM, Joe Shipman wrote:
> My concern is simpler than this. I just want to know where there exists a computer program which takes as inputs the fine-structure constant and a desired output precision and returns a prediction of the magnetic moment of the electron to the requested precision, whether or not the program has good convergence properties.

No. There is no program where you could specify a desired accuracy in 
advance. Quantum field theory is too difficult a subject to allow that 
at the present time.

Nobody has written any code for getting higher than alpha^6 
approximations for QED (and far less for other quantum field theories), 
and even the alpha^6 term is currently incomplete  (and gives a result 
of unknown accuracy), as for tractability only the contributions deemed 
most relevant are included.


> I want a pointer to a reference work

The pointers that exist (and are given in my FAQ entry mentioned before) 
point to far less, but point to what is common practice in reporting 
high precision physics calculations.


Arnold