35 lines
1.2 KiB
Text
35 lines
1.2 KiB
Text
/-
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Copyright (c) 2024 Joseph Tooby-Smith. All rights reserved.
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Released under Apache 2.0 license as described in the file LICENSE.
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Authors: Joseph Tooby-Smith
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-/
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import HepLean.PertubationTheory.Wick.Contract
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/-!
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# Wick contraction in momentum space
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Every complete Wick contraction leads to a function on momenta, following
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the Feynman rules.
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-/
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namespace Wick
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informal_definition toMomentumTensorTree where
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math :≈ "A function which takes a Wick contraction,
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and corresponding momenta, and outputs the corresponding
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tensor tree associated with that contraction. The rules for how this is done
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is given by the `Feynman rules`.
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The appropriate ring to consider here is a ring permitting the abstract notion of a
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Dirac delta function. "
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ref :≈ "
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Some references for Feynman rules are:
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- QED Feynman rules: http://hitoshi.berkeley.edu/public_html/129A/point.pdf,
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- Weyl Fermions: http://scipp.ucsc.edu/~haber/susybook/feyn115.pdf."
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informal_definition toMomentumTensor where
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math :≈ "The tensor associated to `toMomentumTensorTree` associated with a Wick contraction,
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and corresponding internal momenta, and external momenta."
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deps :≈ [``toMomentumTensorTree]
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end Wick
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