PhysLean/docs/CuratedNotes/PerturbationTheory.html

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<!-- Note header (title, curators, notice etc.). -->
<center><h1 style="font-size: 50px;">{{ site.data.perturbationTheory.title }}</h1></center>
<center><h2 style="font-size: 20px;">Note Authors: {{ site.data.perturbationTheory.curators }}</h2></center>
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<div style="border: 1px solid black; padding: 10px;">
  <p>
  These notes are created using an interactive theorem
  prover called <a href="https://lean-lang.org">Lean</a>.
  Lean formally checks definitions, theorems and proofs for correctness.
  These notes are part of a much larger project called
  <a href="https://github.com/HEPLean/HepLean">HepLean</a>, which aims to digitalize
  high energy physics into Lean. Please consider contributing to this project.
  <br><br>
  Please provide feedback or suggestions for improvements by creating a GitHub issue
  <a href="https://github.com/HEPLean/HepLean/issues">here</a>.
  </p>
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