feat: Add defn of Wick Species

HepLean/FeynmanDiagrams/Wick/Algebra.lean

@@ -3,8 +3,7 @@ Copyright (c) 2024 Joseph Tooby-Smith. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Joseph Tooby-Smith
 -/
-import HepLean.FeynmanDiagrams.Basic
-import HepLean.Meta.Informal
+import HepLean.FeynmanDiagrams.Wick.Species
 /-!
 
 # Operator algebra
@@ -24,7 +23,7 @@ We will formally define the operator ring, in terms of the fields present in the
   https://physics.stackexchange.com/q/461929
 -/
 
-namespace TwoComplexScalar
+namespace Wick
 open CategoryTheory
 open FeynmanDiagram
 open PreFeynmanRule
@@ -102,4 +101,4 @@ informal_lemma timeOrder_pair where
 
 /-! TODO: Need to set up data and structure for vaccum expectation values. -/
 
-end TwoComplexScalar
+end Wick

HepLean/FeynmanDiagrams/Wick/Species.lean

@@ -3,7 +3,8 @@ Copyright (c) 2024 Joseph Tooby-Smith. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Joseph Tooby-Smith
 -/
-import HepLean.FeynmanDiagrams.Wick.String
+import HepLean.FeynmanDiagrams.Basic
+import HepLean.Meta.Informal
 /-!
 
 # Wick Species
@@ -18,5 +19,20 @@ for a theory, and calculate their corresponding Feynman diagrams.
 /-! TODO: There should be some sort of notion of a group action on a Wick Species. -/
 namespace Wick
 
+/-- The basic structure needed to write down Wick contractions for a theory and
+  calculate the corresponding Feynman diagrams.
+
+  WARNING: This definition is not yet complete. -/
+structure Species where
+  /-- The color of Field operators which appear in a theory. -/
+  𝓕 : Type
+  /-- The map taking a field operator to its dual operator. -/
+  ξ : 𝓕 → 𝓕
+  /-- The condition that `ξ` is an involution. -/
+  ξ_involutive : Function.Involutive ξ
+  /-- The color of vertices which appear in a theory. -/
+  𝓥 : Type
+  /-- The number of edges each vertex corresponds to. -/
+  𝓥Fields : 𝓥 → Σ n, Fin n → 𝓕
 
 end Wick

HepLean/FeynmanDiagrams/Wick/String.lean

@@ -3,8 +3,7 @@ Copyright (c) 2024 Joseph Tooby-Smith. All rights reserved.
 Released under Apache 2.0 license as described in the file LICENSE.
 Authors: Joseph Tooby-Smith
 -/
-import HepLean.FeynmanDiagrams.Basic
-import HepLean.Meta.Informal
+import HepLean.FeynmanDiagrams.Wick.Species
 /-!
 # Wick strings