@@ -173,11 +173,11 @@ particular, the quantum dimensions ``d_a`` and Frobenius-Schur phase ``χ_a`` an
173173(only if `` a == \overline{a} `` ) are encoded in the F-symbol. They are obtained as
174174[ ` dim(a) ` ] ( @ref ) , [ ` frobenius_schur_phase(a) ` ] ( @ref ) and
175175[ ` frobenius_schur_indicator(a) ` ] ( @ref ) . These functions have default definitions which
176- compute the requested data from ` Fsymbol(a, conj(a), a, a, one (a), one (a)) ` , but they can be
177- overloaded in case the value can be computed more efficiently. The same holds for related
176+ compute the requested data from ` Fsymbol(a, conj(a), a, a, unit (a), unit (a)) ` , but they can
177+ be overloaded in case the value can be computed more efficiently. The same holds for related
178178fusion manipulations such as the B-symbol, which is obtained as [ ` Bsymbol(a, b, c) ` ] ( @ref ) .
179179Finally, the twist associated with a sector ` a ` is obtained as [ ` twist(a) ` ] ( @ref ) , which
180- also has a default implementation in terms of the R-symbol. In addition, tThe function
180+ also has a default implementation in terms of the R-symbol. In addition, the function
181181` isunit ` is provided to facilitate checking whether a sector is a unit sector, in particular
182182for the non-trivial case of the multi-fusion category case, which we do not discuss here.
183183
@@ -374,7 +374,7 @@ Irrep[U₁](0.5)
374374U1Irrep(0.4)
375375U1Irrep(1) ⊗ Irrep[U₁](1//2)
376376u = first(U1Irrep(1) ⊗ Irrep[U₁](1//2))
377- Nsymbol(u, conj (u), one (u))
377+ Nsymbol(u, dual (u), unit (u))
378378```
379379
380380We similarly implement the irreps of the finite cyclic groups `` \mathbb{Z}_N `` , where we
@@ -505,7 +505,7 @@ explicitly restricted the scalar type of `SU2Irrep` to `Float64` for efficiency.
505505The following example illustrates the usage of ` SU2Irrep `
506506``` @repl sectors
507507s = SU2Irrep(3//2)
508- conj (s)
508+ dual (s)
509509dim(s)
510510collect(s ⊗ s)
511511for s2 in s ⊗ s
@@ -516,17 +516,19 @@ end
516516```
517517
518518Other non-abelian groups for which the irreps are implemented are the dihedral groups
519- `` \mathsf{D}_N `` , and the semidirect product `` \mathsf{U}₁ ⋉ ℤ_2 `` . In the context of
520- quantum systems, the latter occurs in the case of systems with particle hole symmetry and
521- the non-trivial element of `` ℤ_2 `` acts as charge conjugation `` C `` . It has the effect of
522- interchaning `` \mathsf{U}_1 `` irreps `` n `` and `` -n `` , and turns them together in a joint
523- 2-dimensional index, except for the case `` n=0 `` . Irreps are therefore labeled by integers
524- `` n ≧ 0 `` , however for `` n=0 `` the `` ℤ₂ `` symmetry can be realized trivially or
525- non-trivially, resulting in an even and odd one-dimensional irrep with `` \mathsf{U})_1 ``
526- charge `` 0 `` . Given `` \mathsf{U}_1 ≂ \mathsf{SO}_2 `` , this group is also simply known as
527- `` \mathsf{O}_2 `` , and the two representations with `` n = 0 `` are the scalar and
528- pseudo-scalar, respectively. However, because we also allow for half integer
529- representations, we refer to it as ` Irrep[CU₁] ` or ` CU1Irrep ` in full.
519+ `` \mathsf{D}_N `` , the alternating group of order four `` mathsf{A}_4 `` and the semidirect
520+ product `` \mathsf{U}₁ ⋉ ℤ_2 `` . In the context of quantum systems, the latter occurs in the
521+ case of systems with particle hole symmetry and the non-trivial element of `` ℤ_2 `` acts as
522+ charge conjugation `` C `` . It has the effect of interchanging `` \mathsf{U}_1 `` irreps `` n ``
523+ and `` -n `` , and turns them together in a joint two-dimensional index, except for the case
524+ `` n=0 `` . Irreps are therefore labeled by integers `` n ≧ 0 `` , however for `` n=0 `` the `` ℤ₂ ``
525+ symmetry can be realized trivially or non-trivially, resulting in an even and odd
526+ one-dimensional irrep with `` \mathsf{U}_1 `` charge `` 0 `` . Given
527+ `` \mathsf{U}_1 ≂ \mathsf{SO}_2 `` , this group is also simply known as `` \mathsf{O}_2 `` , and
528+ the two representations with `` n = 0 `` are the scalar and pseudo-scalar, respectively.
529+ However, because we also allow for half integer representations, we refer to it as
530+ ` Irrep[CU₁] ` or ` CU1Irrep ` in full.
531+
530532``` julia
531533struct CU1Irrep <: AbstractIrrep{CU₁}
532534 j:: HalfInt # value of the U1 charge
@@ -556,8 +558,8 @@ the different cases for the arguments of `Fsymbol`. For the dihedrial groups
556558the representation theory is obtained quite similarly, and is implmented as the type
557559[ ` DNIrrep{N} ` ] ( @ref ) .
558560
559- By default, none of the groups mentioned above have a reprenenstation theory for which
560- ` FusionStyle(I) == GenericFusion() ` , i.e. where fusion mulitplicities are required. An
561+ Of the aforementioned groups, only `` mathsf{A}_4 `` has a representation theory for which
562+ ` FusionStyle(I) == GenericFusion() ` , i.e. where fusion mulitplicities are required. Another
561563example where this does appear is for the irreps of ` SU{N} ` for ` N>2 ` . Such sectors are
562564supported through
563565[ SUNRepresentations.jl] ( https://github.com/QuantumKitHub/SUNRepresentations.jl ) , which
@@ -575,22 +577,22 @@ examples
575577``` @repl sectors
576578a = Z3Irrep(1) ⊠ Irrep[U₁](1)
577579typeof(a)
578- conj (a)
579- one (a)
580+ dual (a)
581+ unit (a)
580582dim(a)
581583collect(a ⊗ a)
582584FusionStyle(a)
583585b = Irrep[ℤ₃](1) ⊠ Irrep[SU₂](3//2)
584586typeof(b)
585- conj (b)
586- one (b)
587+ dual (b)
588+ unit (b)
587589dim(b)
588590collect(b ⊗ b)
589591FusionStyle(b)
590592c = Irrep[SU₂](1) ⊠ SU2Irrep(3//2)
591593typeof(c)
592- conj (c)
593- one (c)
594+ dual (c)
595+ unit (c)
594596dim(c)
595597collect(c ⊗ c)
596598FusionStyle(c)
@@ -608,7 +610,7 @@ used to create `ProductSector{Tuple{Irrep[ℤ₃], Irrep[CU₁]}}`. Instances of
608610constructed by giving a number of arguments, where the first argument is used to construct
609611the first sector, and so forth. Furthermore, for representations of groups, we also enabled
610612the notation ` Irrep[ℤ₃ × CU₁] ` , with ` × ` obtained using ` \times+TAB ` . However, this is
611- merely for convience , as ` Irrep[ℤ₃] ⊠ Irrep[CU₁] ` is not a subtype of the abstract type
613+ merely for convenience , as ` Irrep[ℤ₃] ⊠ Irrep[CU₁] ` is not a subtype of the abstract type
612614` AbstractIrrep{ℤ₃ × CU₁} ` . As is often the case with the Julia type system, the purpose of
613615subtyping ` AbstractIrrep ` was to share common functionality and thereby simplify the
614616implementation of irreps of the different groups discussed above, but not to express a
@@ -831,13 +833,13 @@ Finally, as mentioned above, a recent extension prepares TensorKitSectors.jl to
831833multi-fusion categories, where the sectors (simple objects) are organized in a matrix-like
832834structure and thus have an additional row and column index. Fusion between sectors is only
833835possible when the row and column indices match appropriately; otherwise the fusion product
834- is empty. In this structure, the different groups of " diagonal" sectors define separate
835- fusion categories, whereas the off-diagonal sectors define bimodule categories between these
836- fusion categories. Every diagonal group has its own unit sector, which also acts as the left
837- / right unit for other sectors in the same column / row. The global unit object is not
838- simple, but rather given by the direct sum of all diagonal unit sectors. We do not document
839- or illustrate this structure here, but refer to the relevant functions [ ` leftunit ` ] ( @ref ) ,
840- [ ` rightunit ` ] ( @ref ) , [ ` allunits ` ] ( @ref ) and [ ` UnitStyle ` ] ( @ref ) for more information.
841- Furthermore, we refer to
836+ is empty. In this structure, the different * diagonal* sectors define separate fusion
837+ categories, whereas the * off-diagonal* sectors define bimodule categories between these
838+ fusion categories. Every diagonal set of sectors has its own unit sector, which also acts as
839+ the left / right unit for other sectors in the same column / row. The global unit object is
840+ not simple, but rather given by the direct sum of all diagonal unit sectors. We do not
841+ document or illustrate this structure here, but refer to the relevant functions
842+ [ ` leftunit ` ] ( @ref ) , [ ` rightunit ` ] ( @ref ) , [ ` allunits ` ] ( @ref ) and [ ` UnitStyle ` ] ( @ref ) for more
843+ information. Furthermore, we refer to
842844[ MultiTensorKit.jl] ( https://github.com/QuantumKitHub/MultiTensorKit.jl ) for examples and
843- ongoing development work on using multi-fusion categories.
845+ ongoing development work on using multi-fusion categories.
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