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0110dee | 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 | β Quantum Error Correction: APL Code Generator
β Systematic exploration of stabilizer codes
β Generates candidate codes and tests properties
β result β GenerateStabilizerCode n k;S;i;j;pauli
β Generate random stabilizer code [[n,k,d]]
β n: physical qubits, k: logical qubits
β Need n-k stabilizer generators
S β β¬
:For i :In β³(n-k)
β Random Pauli string (I,X,Y,Z = 0,1,2,3)
pauli β ?(nβ΄4)
S β S,βpauli
:EndFor
β Verify commutativity (all stabilizers must commute)
:If ~VerifyCommutativity S
result β β¬ β Invalid code
β0
:EndIf
β Compute distance (simplified)
d β ComputeDistance S n
result β (n k d S)
β
β valid β VerifyCommutativity stabilizers;s1;s2
β Check if all stabilizers commute
valid β 1
:For s1 :In stabilizers
:For s2 :In stabilizers
:If ~Commute s1 s2
valid β 0
β0
:EndIf
:EndFor
:EndFor
β
β commutes β Commute p1 p2;pauli_product
β Check if two Pauli strings commute
β Pauli strings commute if they differ in even number of positions
β where both are non-identity and different
pauli_product β +/((p1β 0)β§(p2β 0)β§(p1β p2))
commutes β ~2|pauli_product β Even number of anti-commuting pairs
β
β d β ComputeDistance stabilizers n;min_weight;weight;error
β Compute code distance (minimum weight logical operator)
β Simplified: search for low-weight errors
min_weight β n β Start with maximum
β Search for errors of weight 1, 2, 3, ...
:For weight :In β³3
:For each error of weight weight
β Check if error commutes with all stabilizers
β but is not in stabilizer group
:If (CommutesWithAll error stabilizers) β§ (~InStabilizerGroup error stabilizers)
min_weight β β/min_weight weight
:EndIf
:EndFor
:EndFor
d β min_weight
β
β result β SearchCodeSpace n_min n_max;best_code;best_score;code;score
β Systematic search over code parameters
best_code β β¬
best_score β 0
:For n :In β³(n_max-n_min+1)+n_min-1
:For k :In β³n-1
code β GenerateStabilizerCode n k
:If code β’ β¬ β Valid code
β Score: balance rate, distance, and threshold
rate β kΓ·n
score β rate Γ code[3] Γ 0.01 β Simplified threshold
:If score > best_score
best_score β score
best_code β code
ββ'Found: [[',n,',',k,',',code[3],']] rate=',rate
:EndIf
:EndIf
:EndFor
:EndFor
result β (best_code best_score)
β
β sealed β SealToWORM code;hash;timestamp
β Seal discovered code to WORM ledger
hash β SHA256 βcode
timestamp β ββTS
sealed β 'qec-',hash,'-',timestamp
β Append to ledger
'qec_worm.jsonl' AppendToFile sealed,'|',βcode
β
β Known codes for comparison
β codes β KnownCodes
β Return list of known quantum codes
codes β β
(5,1,3) β Perfect code
(7,1,3) β Steane code
(9,1,3) β Shor code
(23,1,7) β Golay-based code
β
β Surface code benchmark
β surface β SurfaceCode d
β Surface code with distance d
β Uses 2dΒ²-1 physical qubits, encodes 1 logical qubit
surface β (2Γd*2)-1
surface β (surface,1,d)
β
β Example usage:
β result β SearchCodeSpace 5 15
β best_code β result[1]
β best_score β result[2]
β SealToWORM best_code
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