Disallow dual physical spaces for symmetries with non-trivial braiding (#284)

* Disallow dual physical spaces for symmetries with non-trivial braiding

* Update error message for iPEPO

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Co-authored-by: Yue Zhengyuan <yuezy1997@icloud.com>

Author: leburgel

src/operators/infinitepepo.jl

@@ -12,7 +12,10 @@ struct InfinitePEPO{T <: PEPOTensor}
     InfinitePEPO{T}(A::Array{T, 3}) where {T} = new{T}(A)
     function InfinitePEPO(A::Array{T, 3}) where {T <: PEPOTensor}
         # space checks
+        bosonic_braiding = BraidingStyle(sectortype(T)) === Bosonic()
         for (d, w, h) in Tuple.(CartesianIndices(A))
+            (bosonic_braiding || (!isdual(domain_physicalspace(A[d, w, h])) && !isdual(codomain_physicalspace(A[d, w, h])))) ||
+                throw(ArgumentError("Dual physical spaces for symmetry sectors with non-trivial twists are not allowed (for now)."))
             codomain_physicalspace(A[d, w, h]) == domain_physicalspace(A[d, w, _next(h, end)]) ||
                 throw(SpaceMismatch("Physical space at site $((d, w, h)) does not match."))
             north_virtualspace(A[d, w, h]) == south_virtualspace(A[_prev(d, end), w, h])' ||

src/states/infinitepeps.jl

@@ -11,7 +11,10 @@ struct InfinitePEPS{T <: PEPSTensor}
     A::Matrix{T}
     InfinitePEPS{T}(A::Matrix{T}) where {T <: PEPSTensor} = new{T}(A)
     function InfinitePEPS(A::Array{T, 2}) where {T <: PEPSTensor}
+        bosonic_braiding = BraidingStyle(sectortype(T)) === Bosonic()
         for (d, w) in Tuple.(CartesianIndices(A))
+            (bosonic_braiding || !isdual(physicalspace(A[d, w]))) ||
+                throw(ArgumentError("Dual physical spaces for symmetry sectors with non-trivial twists are not allowed (for now)."))
             north_virtualspace(A[d, w]) == south_virtualspace(A[_prev(d, end), w])' ||
                 throw(
                 SpaceMismatch("North virtual space at site $((d, w)) does not match.")