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Fix CTMRG contraction inconsistencies #327

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Merged
Yue-Zhengyuan merged 12 commits into from
Jan 30, 2026
Merged

Fix CTMRG contraction inconsistencies #327

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c98c29c
Fix fullinf_env
pbrehmer Jan 29, 2026
bf1117a
Fix gaugefix
pbrehmer Jan 29, 2026
3fa9074
Fix halfinf_env
pbrehmer Jan 29, 2026
a05563f
Fix projector
pbrehmer Jan 29, 2026
0adae13
Fix renormalizations
pbrehmer Jan 29, 2026
239e669
Fix renormalization part II
pbrehmer Jan 29, 2026
2e28a6b
Add in and out labels
pbrehmer Jan 29, 2026
b2094ac
Rename bottom and top corner contractions to southwest and northwest
pbrehmer Jan 29, 2026
da03aaf
Actually replace bottom/top corner with southwest/northwest
pbrehmer Jan 29, 2026
d1540ad
Fix gaugefix test
pbrehmer Jan 29, 2026
d20969d
Apply rest of suggestions
pbrehmer Jan 29, 2026
d1b8d69
Merge branch 'fix-contraction-inconsistencies' of github.com:quantumg…
pbrehmer Jan 29, 2026
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36 changes: 14 additions & 22 deletions src/algorithms/contractions/ctmrg/enlarge_corner.jl
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Original file line number Diff line number Diff line change
Expand Up @@ -25,10 +25,11 @@ Contract the enlarged northwest corner of the CTMRG environment, either by speci
coordinates, environments and network, or by directly providing the tensors.

```
C_northwest -- E_north --
C_northwest -- E_north --in
| |
E_west -- A --
| |
out
```
"""
function enlarge_northwest_corner(
Expand All @@ -37,13 +38,10 @@ function enlarge_northwest_corner(
)
return @tensor begin
EC[χS DWt DWb; χ2] := E_west[χS DWt DWb; χ1] * C_northwest[χ1; χ2]

# already putting χE in front here to make next permute cheaper
ECE[χS χE DWb DNb; DWt DNt] := EC[χS DWt DWb; χ2] * E_north[χ2 DNt DNb; χE]

ECEket[χS χE DEt DSt; DWb DNb d] :=
ECE[χS χE DWb DNb; DWt DNt] * ket(A)[d; DNt DEt DSt DWt]

corner[χS DSt DSb; χE DEt DEb] :=
ECEket[χS χE DEt DSt; DWb DNb d] * conj(bra(A)[d; DNb DEb DSb DWb])
end
Expand Down Expand Up @@ -94,10 +92,11 @@ Contract the enlarged northeast corner of the CTMRG environment, either by speci
coordinates, environments and network, or by directly providing the tensors.

```
-- E_north -- C_northeast
| |
-- A -- E_east
| |
out-- E_north -- C_northeast
| |
-- A -- E_east
| |
in
```
"""
function enlarge_northeast_corner(
Expand All @@ -106,13 +105,10 @@ function enlarge_northeast_corner(
)
return @tensor begin
EC[χW DNt DNb; χ2] := E_north[χW DNt DNb; χ1] * C_northeast[χ1; χ2]

# already putting χE in front here to make next permute cheaper
ECE[χW χS DNb DEb; DNt DEt] := EC[χW DNt DNb; χ2] * E_east[χ2 DEt DEb; χS]

ECEket[χW χS DSt DWt; DNb DEb d] :=
ECE[χW χS DNb DEb; DNt DEt] * ket(A)[d; DNt DEt DSt DWt]

corner[χW DWt DWb; χS DSt DSb] :=
ECEket[χW χS DSt DWt; DNb DEb d] * conj(bra(A)[d; DNb DEb DSb DWb])
end
Expand Down Expand Up @@ -163,10 +159,11 @@ Contract the enlarged southeast corner of the CTMRG environment, either by speci
coordinates, environments and network, or by directly providing the tensors.

```
| |
-- A -- E_east
| |
-- E_south -- C_southeast
out
| |
-- A -- E_east
| |
in-- E_south -- C_southeast
```
"""
function enlarge_southeast_corner(
Expand All @@ -175,13 +172,10 @@ function enlarge_southeast_corner(
)
return @tensor begin
EC[χN DEt DEb; χ2] := E_east[χN DEt DEb; χ1] * C_southeast[χ1; χ2]

# already putting χE in front here to make next permute cheaper
ECE[χN χW DEb DSb; DEt DSt] := EC[χN DEt DEb; χ2] * E_south[χ2 DSt DSb; χW]

ECEket[χN χW DNt DWt; DEb DSb d] :=
ECE[χN χW DEb DSb; DEt DSt] * ket(A)[d; DNt DEt DSt DWt]

corner[χN DNt DNb; χW DWt DWb] :=
ECEket[χN χW DNt DWt; DEb DSb d] * conj(bra(A)[d; DNb DEb DSb DWb])
end
Expand Down Expand Up @@ -232,10 +226,11 @@ Contract the enlarged southwest corner of the CTMRG environment, either by speci
coordinates, environments and network, or by directly providing the tensors.

```
in
| |
E_west -- A --
| |
C_southwest -- E_south --
C_southwest -- E_south --out
```
"""
function enlarge_southwest_corner(
Expand All @@ -244,13 +239,10 @@ function enlarge_southwest_corner(
)
return @tensor begin
EC[χE DSt DSb; χ2] := E_south[χE DSt DSb; χ1] * C_southwest[χ1; χ2]

# already putting χE in front here to make next permute cheaper
ECE[χE χN DSb DWb; DSt DWt] := EC[χE DSt DSb; χ2] * E_west[χ2 DWt DWb; χN]

ECEket[χE χN DNt DEt; DSb DWb d] :=
ECE[χE χN DSb DWb; DSt DWt] * ket(A)[d; DNt DEt DSt DWt]

corner[χE DEt DEb; χN DNt DNb] :=
ECEket[χE χN DNt DEt; DSb DWb d] * conj(bra(A)[d; DNb DEb DSb DWb])
end
Expand Down
39 changes: 23 additions & 16 deletions src/algorithms/contractions/ctmrg/fullinf_env.jl
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -12,7 +12,9 @@ Contract four quadrants (enlarged corners) to form a full-infinite environment.
|quadrant1| |quadrant2|
|~~~~~~~~~| -- |~~~~~~~~~|
| | | |
out | |
| |
in | |
| | | |
|~~~~~~~~~| -- |~~~~~~~~~|
|quadrant4| |quadrant3|
Expand All @@ -26,7 +28,9 @@ In the same manner two halfs can be used to contract the full-infinite environme
| half1 |
|~~~~~~~~~~~~~~~~~~~~~~~~|
| | | |
out | |
| |
in | |
| | | |
|~~~~~~~~~~~~~~~~~~~~~~~~|
| half2 |
Expand All @@ -40,7 +44,9 @@ The environment can also be contracted directly from all its constituent tensors
| | | |
E_1 -- A_1 -- A_2 -- E_4
| | | |
out | |
| |
in | | |
| | | |
E_8 -- A_4 -- A_3 -- E_5
| | | |
Expand All @@ -54,6 +60,7 @@ Alternatively, contract the environment with a vector `x` acting on it
| | | |
E_1 -- A_1 -- A_2 -- E_4
| | | |
out | |
| |
[~~~~x~~~] | |
| | | |
Expand Down Expand Up @@ -112,25 +119,25 @@ function full_infinite_environment(
E_1, E_2, E_3, E_4, E_5, E_6, E_7, E_8,
A_1::P, A_2::P, A_3::P, A_4::P,
) where {P <: PEPSSandwich}
return @autoopt @tensor env[χ_in D_inabove D_inbelow; χ_out D_outabove D_outbelow] :=
E_1[χ_in D1 D2; χ1] * C_1[χ1; χ2] * E_2[χ2 D3 D4; χ3] *
ket(A_1)[d1; D3 D11 D_inabove D1] * conj(bra(A_1)[d1; D4 D12 D_inbelow D2]) *
return @autoopt @tensor env[χ_out D_outabove D_outbelow; χ_in D_inabove D_inbelow] :=
E_1[χ_out D1 D2; χ1] * C_1[χ1; χ2] * E_2[χ2 D3 D4; χ3] *
ket(A_1)[d1; D3 D11 D_outabove D1] * conj(bra(A_1)[d1; D4 D12 D_outbelow D2]) *
ket(A_2)[d2; D5 D7 D9 D11] * conj(bra(A_2)[d2; D6 D8 D10 D12]) *
E_3[χ3 D5 D6; χ4] * C_2[χ4; χ5] * E_4[χ5 D7 D8; χ6] *
E_5[χ6 D13 D14; χ7] * C_3[χ7; χ8] * E_6[χ8 D15 D16; χ9] *
ket(A_3)[d3; D9 D13 D15 D17] * conj(bra(A_3)[d3; D10 D14 D16 D18]) *
ket(A_4)[d4; D_outabove D17 D19 D21] * conj(bra(A_4)[d4; D_outbelow D18 D20 D22]) *
E_7[χ9 D19 D20; χ10] * C_4[χ10; χ11] * E_8[χ11 D21 D22; χ_out]
ket(A_4)[d4; D_inabove D17 D19 D21] * conj(bra(A_4)[d4; D_inbelow D18 D20 D22]) *
E_7[χ9 D19 D20; χ10] * C_4[χ10; χ11] * E_8[χ11 D21 D22; χ_in]
end
function full_infinite_environment(
C_1, C_2, C_3, C_4,
E_1, E_2, E_3, E_4, E_5, E_6, E_7, E_8,
x::AbstractTensor{T, S, 3},
A_1::P, A_2::P, A_3::P, A_4::P,
) where {T, S, P <: PEPSSandwich}
return @autoopt @tensor env_x[χ_in D_inabove D_inbelow] :=
E_1[χ_in D1 D2; χ1] * C_1[χ1; χ2] * E_2[χ2 D3 D4; χ3] *
ket(A_1)[d1; D3 D11 D_inabove D1] * conj(bra(A_1)[d1; D4 D12 D_inbelow D2]) *
return @autoopt @tensor env_x[χ_out D_outabove D_outbelow] :=
E_1[χ_out D1 D2; χ1] * C_1[χ1; χ2] * E_2[χ2 D3 D4; χ3] *
ket(A_1)[d1; D3 D11 D_outabove D1] * conj(bra(A_1)[d1; D4 D12 D_outbelow D2]) *
ket(A_2)[d2; D5 D7 D9 D11] * conj(bra(A_2)[d2; D6 D8 D10 D12]) *
E_3[χ3 D5 D6; χ4] * C_2[χ4; χ5] * E_4[χ5 D7 D8; χ6] *
E_5[χ6 D13 D14; χ7] * C_3[χ7; χ8] * E_6[χ8 D15 D16; χ9] *
Expand Down Expand Up @@ -161,25 +168,25 @@ function full_infinite_environment(
E_1, E_2, E_3, E_4, E_5, E_6, E_7, E_8,
A_1::P, A_2::P, A_3::P, A_4::P,
) where {P <: PFTensor}
return @autoopt @tensor env[χ_in D_in; χ_out D_out] :=
E_1[χ_in D1; χ1] * C_1[χ1; χ2] * E_2[χ2 D3; χ3] *
A_1[D1 D_in; D3 D11] *
return @autoopt @tensor env[χ_out D_out; χ_in D_in] :=
E_1[χ_out D1; χ1] * C_1[χ1; χ2] * E_2[χ2 D3; χ3] *
A_1[D1 D_out; D3 D11] *
A_2[D11 D9; D5 D7] *
E_3[χ3 D5; χ4] * C_2[χ4; χ5] * E_4[χ5 D7; χ6] *
E_5[χ6 D13; χ7] * C_3[χ7; χ8] * E_6[χ8 D15; χ9] *
A_3[D17 D15; D9 D13] *
A_4[D21 D19; D_out D17] *
E_7[χ9 D19; χ10] * C_4[χ10; χ11] * E_8[χ11 D21; χ_out]
A_4[D21 D19; D_in D17] *
E_7[χ9 D19; χ10] * C_4[χ10; χ11] * E_8[χ11 D21; χ_in]
end
function full_infinite_environment(
C_1, C_2, C_3, C_4,
E_1, E_2, E_3, E_4, E_5, E_6, E_7, E_8,
x::AbstractTensor{T, S, 2},
A_1::P, A_2::P, A_3::P, A_4::P,
) where {T, S, P <: PFTensor}
return @autoopt @tensor env_x[χ_in D_in] :=
E_1[χ_in D1; χ1] * C_1[χ1; χ2] * E_2[χ2 D3; χ3] *
A_1[D1 D_in; D3 D11] *
return @autoopt @tensor env_x[χ_out D_out] :=
E_1[χ_out D1; χ1] * C_1[χ1; χ2] * E_2[χ2 D3; χ3] *
A_1[D1 D_out; D3 D11] *
A_2[D11 D9; D5 D7] *
E_3[χ3 D5; χ4] * C_2[χ4; χ5] * E_4[χ5 D7; χ6] *
E_5[χ6 D13; χ7] * C_3[χ7; χ8] * E_6[χ8 D15; χ9] *
Expand Down
26 changes: 14 additions & 12 deletions src/algorithms/contractions/ctmrg/gaugefix.jl
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Original file line number Diff line number Diff line change
Expand Up @@ -9,17 +9,18 @@ $(SIGNATURES)
Multiply corner tensor with incoming and outgoing gauge signs.

```
corner -- σ_out --
corner -- σ_in --in
|
σ_in
σ_out
|
out
```
"""
function fix_gauge_corner(
corner::CTMRGCornerTensor, σ_in::CTMRGCornerTensor, σ_out::CTMRGCornerTensor
corner::CTMRGCornerTensor, σ_out::CTMRGCornerTensor, σ_in::CTMRGCornerTensor
)
return @autoopt @tensor corner_fix[χ_in; χ_out] :=
σ_in[χ_in; χ1] * corner[χ1; χ2] * conj(σ_out[χ_out; χ2])
return @autoopt @tensor corner_fix[χ_out; χ_in] :=
σ_out[χ_out; χ1] * corner[χ1; χ2] * conj(σ_in[χ_in; χ2])
end

"""
Expand Down Expand Up @@ -82,25 +83,26 @@ $(SIGNATURES)
Multiply edge tensor with incoming and outgoing gauge signs.

```
-- σ_in -- edge -- σ_out --
out-- σ_out -- edge -- σ_in --in
|
```
"""
@generated function fix_gauge_edge(
edge::CTMRGEdgeTensor{T, S, N}, σ_in::CTMRGCornerTensor, σ_out::CTMRGCornerTensor
edge::CTMRGEdgeTensor{T, S, N}, σ_out::CTMRGCornerTensor, σ_in::CTMRGCornerTensor
) where {T, S, N}
edge_fix_e = tensorexpr(
:edge_fix,
(envlabel(:in), ntuple(i -> virtuallabel(i), N - 1)...),
(envlabel(:out),),
(envlabel(:out), ntuple(i -> virtuallabel(i), N - 1)...),
(envlabel(:in),),
)
edge_e = tensorexpr(
:edge, (envlabel(1), ntuple(i -> virtuallabel(i), N - 1)...), (envlabel(2),)
)
σ_in_e = tensorexpr(:σ_in, (envlabel(:in),), (envlabel(1),))
σ_out_e = tensorexpr(:σ_out, (envlabel(:out),), (envlabel(2),))
σ_out_e = tensorexpr(:σ_out, (envlabel(:out),), (envlabel(1),))
σ_in_e = tensorexpr(:σ_in, (envlabel(:in),), (envlabel(2),))
return macroexpand(
@__MODULE__,
:(return @autoopt @tensor $edge_fix_e := $σ_in_e * $edge_e * conj($σ_out_e)),
:(return @autoopt @tensor $edge_fix_e := $σ_out_e * $edge_e * conj($σ_in_e)),
)
end

Expand Down
34 changes: 18 additions & 16 deletions src/algorithms/contractions/ctmrg/halfinf_env.jl
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Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -11,6 +11,7 @@ Contract two quadrants (enlarged corners) to form a half-infinite environment.
|quadrant1| |quadrant2|
|~~~~~~~~~| -- |~~~~~~~~~|
| | | |
out in
```

The environment can also be contracted directly from all its constituent tensors.
Expand All @@ -20,6 +21,7 @@ The environment can also be contracted directly from all its constituent tensors
| | | |
E_1 -- A_1 -- A_2 -- E_4
| | | |
out in
```

Alternatively, contract the environment with a vector `x` acting on it
Expand All @@ -29,7 +31,7 @@ Alternatively, contract the environment with a vector `x` acting on it
| | | |
E_1 -- A_1 -- A_2 -- E_4
| | | |
[~~~x~~~~]
out [~~~x~~~~]
```

or contract the adjoint environment with `x`, e.g. as needed for iterative solvers.
Expand All @@ -43,18 +45,18 @@ end
function half_infinite_environment(
C_1, C_2, E_1, E_2, E_3, E_4, A_1::P, A_2::P
) where {P <: PEPSSandwich}
return @autoopt @tensor env[χ_in D_inabove D_inbelow; χ_out D_outabove D_outbelow] :=
E_1[χ_in D1 D2; χ1] * C_1[χ1; χ2] * E_2[χ2 D3 D4; χ3] *
ket(A_1)[d1; D3 D9 D_inabove D1] * conj(bra(A_1)[d1; D4 D10 D_inbelow D2]) *
ket(A_2)[d2; D5 D7 D_outabove D9] * conj(bra(A_2)[d2; D6 D8 D_outbelow D10]) *
return @autoopt @tensor env[χ_out D_outabove D_outbelow; χ_in D_inabove D_inbelow] :=
E_1[χ_out D1 D2; χ1] * C_1[χ1; χ2] * E_2[χ2 D3 D4; χ3] *
ket(A_1)[d1; D3 D9 D_outabove D1] * conj(bra(A_1)[d1; D4 D10 D_outbelow D2]) *
ket(A_2)[d2; D5 D7 D_inabove D9] * conj(bra(A_2)[d2; D6 D8 D_inbelow D10]) *
E_3[χ3 D5 D6; χ4] * C_2[χ4; χ5] * E_4[χ5 D7 D8; χ_out]
end
function half_infinite_environment(
C_1, C_2, E_1, E_2, E_3, E_4, x::AbstractTensor{T, S, 3}, A_1::P, A_2::P
) where {T, S, P <: PEPSSandwich}
return @autoopt @tensor env_x[χ_in D_inabove D_inbelow] :=
E_1[χ_in D1 D2; χ1] * C_1[χ1; χ2] * E_2[χ2 D3 D4; χ3] *
ket(A_1)[d1; D3 D9 D_inabove D1] * conj(bra(A_1)[d1; D4 D10 D_inbelow D2]) *
return @autoopt @tensor env_x[χ_out D_outabove D_outbelow] :=
E_1[χ_out D1 D2; χ1] * C_1[χ1; χ2] * E_2[χ2 D3 D4; χ3] *
ket(A_1)[d1; D3 D9 D_outabove D1] * conj(bra(A_1)[d1; D4 D10 D_outbelow D2]) *
ket(A_2)[d2; D5 D7 D11 D9] * conj(bra(A_2)[d2; D6 D8 D12 D10]) *
E_3[χ3 D5 D6; χ4] * C_2[χ4; χ5] * E_4[χ5 D7 D8; χ6] *
x[χ6 D11 D12]
Expand All @@ -72,18 +74,18 @@ end
function half_infinite_environment(
C_1, C_2, E_1, E_2, E_3, E_4, A_1::P, A_2::P
) where {P <: PFTensor}
return @autoopt @tensor env[χ_in D_in; χ_out D_out] :=
E_1[χ_in D1; χ1] * C_1[χ1; χ2] * E_2[χ2 D3; χ3] *
A_1[D1 D_in; D3 D9] *
A_2[D9 D_out; D5 D7] *
E_3[χ3 D5; χ4] * C_2[χ4; χ5] * E_4[χ5 D7; χ_out]
return @autoopt @tensor env[χ_out D_out; χ_in D_in] :=
E_1[χ_out D1; χ1] * C_1[χ1; χ2] * E_2[χ2 D3; χ3] *
A_1[D1 D_out; D3 D9] *
A_2[D9 D_in; D5 D7] *
E_3[χ3 D5; χ4] * C_2[χ4; χ5] * E_4[χ5 D7; χ_in]
end
function half_infinite_environment(
C_1, C_2, E_1, E_2, E_3, E_4, x::AbstractTensor{T, S, 2}, A_1::P, A::P
) where {T, S, P <: PFTensor}
return @autoopt @tensor env_x[χ_in D_in] :=
E_1[χ_in D1; χ1] * C_1[χ1; χ2] * E_2[χ2 D3; χ3] *
A_1[D1 D_in; D3 D9] *
return @autoopt @tensor env_x[χ_out D_out] :=
E_1[χ_out D1; χ1] * C_1[χ1; χ2] * E_2[χ2 D3; χ3] *
A_1[D1 D_out; D3 D9] *
A_2[D9 D11; D5 D7] *
E_3[χ3 D5; χ4] * C_2[χ4; χ5] * E_4[χ5 D7; χ6] *
x[χ6 D11]
Expand Down
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