Where Can I Find Hamiltonians of the Standard Model in QFT?

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SUMMARY

The discussion centers on the challenge of finding Hamiltonians corresponding to the Lagrangians of the Standard Model in Quantum Field Theory (QFT). Participants highlight the complexities involved in the Hamiltonian formulation, including the loss of manifest Poincare covariance and the hidden gauge symmetries. Key references provided include a lecture from the University of Graz and a CERN document, which may assist in understanding these Hamiltonians. The conversation also touches on the relevance of eigenvalue equations in QFT.

PREREQUISITES
  • Understanding of Quantum Field Theory (QFT)
  • Familiarity with the Standard Model of particle physics
  • Knowledge of Hamiltonian mechanics
  • Experience with gauge symmetries and their implications
NEXT STEPS
  • Study the Hamiltonian formulation of Quantum Chromodynamics (QCD)
  • Review the provided references for detailed treatments of Hamiltonians in QFT
  • Learn about the role of eigenvalue equations in Quantum Field Theory
  • Explore regularization techniques in the Hamiltonian approach
USEFUL FOR

Physicists, particularly those specializing in Quantum Field Theory, theoretical physicists, and students seeking to deepen their understanding of the Hamiltonian formulation of the Standard Model.

metroplex021
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Hi all - as everyone knows, the fundamental laws of the Standard Model are almost always presented in Lagrangian form. Can anyone tell me of anywhere (such as a textbook) that I might find the Hamiltonians corresponding to these Lagrangians written out? (I'm confused on a couple of points and am having loads of trouble working it out myself.) Any tips received with gratitude!
 
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The Hamiltonian formulation is usually rather ugly due to several reasons:

Manifest Poincare covariance is lost b/c time t and the Hamiltonian H are singled out. Whereas in the Lagrangian the symmetry is explicitly visible, in the Hamiltonian (and all other generators of the Poincare algebra) the symmetry is hidden and has to be checked explicitly.

Something similar happens with the gauge symmetries. They are explicitly visible in te Lagrangian but "fixed" in the Hamiltonian. This can be achieved in various different ways, e.g. via eliminating unphysical degrees of freedom which means reducing 4 to 2 gauge degrees of freedom (the transversal polarization states). Doing this results in physical degrees of freedom but unfortunately generates rather complicated interaction terms which in some cases can not be written down explicitly.

In addition in order to construct the Hamiltonian you have to construct the (physical) Hilbert space with an inner product AND you have to regularize all expressions. You have to regularize in the Lagrangian (or path integral) approach as well, but there you can do it on the level of Greens functions or matrix elements, so in a sense one step later. Therefore the Lagrangian itself still looks nice whereas the complexity is present in the matrix elements. In the Hamiltonian approach things are more intertwined and already the Hamiltonian gets more complicated.

To cut a long story short: I do not know about a standard textbook treatment of QCD, but I can give you some references where you can check the details.

http://physik.uni-graz.at/itp/oberw/oberw08/Vortraege/reinhardt_oberwoelz08.pdf
http://cdsweb.cern.ch/record/292166/files/9511450.pdf
http://www.adsabs.harvard.edu/abs/1994AnPhy.233..317L
 
Thank you *very* much for that - awesome of you Part of what I was wondering was whether anyone has any use for eigenvalue equations in QFT. Now it seems that they do. Thanks mate.
 

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