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Typos and small updates to docs
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lkdvos committed Nov 1, 2023
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2 changes: 1 addition & 1 deletion docs/src/man/sectors.md
Original file line number Diff line number Diff line change
Expand Up @@ -238,7 +238,7 @@ struct Fermionic <: SymmetricBraiding end
struct Anyonic <: BraidingStyle end
```
New sector types `I<:Sector` should then indicate which fusion style they have by defining
`BraidingStyle(::Type{})`. Note that `Bosonic()` braiding does not mean that all
`BraidingStyle(::Type{I})`. Note that `Bosonic()` braiding does not mean that all
permutations are trivial and ``R^{ab}_c = 1``, but that ``R^{ab}_c R^{ba}_c = 1``. For
example, for the irreps of ``\mathsf{SU}_2``, the R-symbol associated with the fusion of
two spin-1/2 particles to spin zero is ``-1``, i.e. the singlet of two spin-1/2 particles
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42 changes: 21 additions & 21 deletions docs/src/man/tutorial.md
Original file line number Diff line number Diff line change
Expand Up @@ -260,7 +260,7 @@ dim(V2)
A = Tensor(randn, V1*V1*V2')
convert(Array, A)
```
Here, we create a space 5-dimensional space `V1`, which has a three-dimensional subspace
Here, we create a 5-dimensional space `V1`, which has a three-dimensional subspace
associated with charge 0 (the trivial irrep of ``ℤ₂``) and a two-dimensional subspace with
charge 1 (the non-trivial irrep). Similar for `V2`, where both subspaces are one-
dimensional. Representing the tensor as a dense `Array`, we see that it is zero in those
Expand Down Expand Up @@ -288,21 +288,22 @@ A = TensorMap(randn, V*V, V)
dim(A)
convert(Array, A)
V = GradedSpace[Irrep[U₁×ℤ₂]]((0,0)=>2,(1,1)=>1,(-1,0)=>1)
V = Rep[U₁×ℤ₂]((0, 0) => 2, (1, 1) => 1, (-1, 0) => 1)
dim(V)
A = TensorMap(randn, V*V, V)
dim(A)
convert(Array, A)
```
Here, the `dim` of a `TensorMap` returns the number of linearly independent components,
i.e. the number of non-zero entries in the case of an abelian symmetry. Also note that we
can use `×` (obtained as `\times+TAB`) to combine different symmetries. The general space
associated with symmetries is a `GradedSpace`. Although this is actually an
abstract type, it is the access point for users to construct spaces with arbitrary
symmetries, and `ℤ₂Space` (also `Z2Space` as non-Unicode alternative) and `U₁Space` (or
`U1Space`) are just convenient synonyms, e.g.
Here, the `dim` of a `TensorMap` returns the number of linearly independent components, i.e.
the number of non-zero entries in the case of an abelian symmetry. Also note that we can use
`×` (obtained as `\times+TAB`) to combine different symmetry groups. The general space
associated with symmetries is a `GradedSpace`, which is parametrized to the type of
symmetry. For a group `G`, the fully specified type can be obtained as `Rep[G]`, while for
more general sectortypes `I` it can be constructed as `Vect[I]`. Furthermore, `ℤ₂Space`
(also `Z2Space` as non-Unicode alternative) and `U₁Space` (or `U1Space`) are just convenient
synonyms, e.g.
```@repl tutorial
GradedSpace[Irrep[U₁]](0=>3,1=>2,-1=>1) == U1Space(-1=>1,1=>2,0=>3)
Rep[U₁](0=>3,1=>2,-1=>1) == U1Space(-1=>1,1=>2,0=>3)
V = U₁Space(1=>2,0=>3,-1=>1)
for s in sectors(V)
@show s, dim(V, s)
Expand All @@ -316,23 +317,22 @@ also supports a grading that is derived from the fusion ring of a (unitary) pre-
category. Also note that the order in which the charges and their corresponding subspace
dimensionality are specified is irrelevant, and that the charges, henceforth called sectors
(which is a more general name for charges or quantum numbers) are of a specific type, in
this case `Irrep[U₁] == U1Irrep`. However, the `GradedSpace[I]` constructor automatically
converts the keys in the list of `Pair`s it receives to the correct type. Alternatively, we
can directly create the sectors of the correct type and use the generic `GradedSpace`

constructor. We can probe the subspace dimension of a certain sector `s` in a space `V`
with `dim(V, s)`. Finally, note that `GradedSpace` is also a subtype of
`EuclideanSpace{ℂ}`, which implies that it still has the standard Euclidean inner product
and we assume all representations to be unitary.
this case `Irrep[U₁] == U1Irrep`. However, the `Vect[I]` constructor automatically converts
the keys in the list of `Pair`s it receives to the correct type. Alternatively, we can
directly create the sectors of the correct type and use the generic `GradedSpace`
constructor. We can probe the subspace dimension of a certain sector `s` in a space `V` with
`dim(V, s)`. Finally, note that `GradedSpace` is also a subtype of `EuclideanSpace`, which
implies that it still has the standard Euclidean inner product and we assume all
representations to be unitary.

TensorKit.jl also allows for non-abelian symmetries such as `SU₂`. In this case, the vector
space is characterized via the spin quantum number (i.e. the irrep label of `SU₂`) for each
of its subspaces, and is created using `SU₂Space` (or `SU2Space` or
`GradedSpace[Irrep[SU₂]]`)
of its subspaces, and is created using `SU₂Space` (or `SU2Space` or `Rep[SU₂]` or
`Vect[Irrep[SU₂]]`)
```@repl tutorial
V = SU₂Space(0=>2,1/2=>1,1=>1)
dim(V)
V == GradedSpace[Irrep[SU₂]](0=>2, 1=>1, 1//2=>1)
V == Vect[Irrep[SU₂]](0=>2, 1=>1, 1//2=>1)
```
Note that now `V` has a two-dimensional subspace with spin zero, and two one-dimensional
subspaces with spin 1/2 and spin 1. However, a subspace with spin `j` has an additional
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