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T3-4-formal: 量子隐形传态定理的形式化证明

机器验证元数据

type: theorem  
verification: machine_ready
dependencies: ["D1-4-formal.md", "T3-1-formal.md", "T3-2-formal.md", "T3-3-formal.md"]
verification_points:
- initial_state_construction
- bell_measurement_protocol
- classical_information_transmission
- unitary_correction_application
- teleportation_fidelity_verification

核心定理

定理 T3-4(量子隐形传态的必然实现)

QuantumTeleportationRealization : Prop ≡
∀ψ : StateVector . ∀siteA, siteB, siteC : Location .
SeparatedSites(siteA, siteC) ∧ EntangledResource(siteB, siteC) →
∃protocol : TeleportationProtocol .
TransferState(ψ, siteA, siteC, protocol) ∧
Fidelity(ψ, protocol) = 1

where
SeparatedSites : No direct quantum channel between sites
EntangledResource : Pre-shared entangled state |Φ+⟩BC
TransferState : Perfect state transfer achieved
Fidelity : Overlap between original and final states

初始态的张量积构造

引理 T3-4.1(三粒子复合态构造)

ThreeParticleCompositeState : Prop ≡
∀ψ : StateVector . ∀entangledPair : BellState .
ψ = α|0⟩ + β|1⟩ ∧ entangledPair = (|00⟩ + |11⟩)/√2 →
CompositeState(ψ, entangledPair) =
(α|0⟩A + β|1⟩A) ⊗ (|00⟩BC + |11⟩BC)/√2

where
CompositeState : Three-particle state |ψ⟩A ⊗ |Φ+⟩BC
A, B, C : Particle labels (Alice, Bob, Charlie)

证明

Proof of composite state construction:
1. Unknown state: |ψ⟩A = α|0⟩A + β|1⟩A
2. Entangled resource: |Φ+⟩BC = (|00⟩BC + |11⟩BC)/√2
3. Tensor product: |Ψ⟩ABC = |ψ⟩A ⊗ |Φ+⟩BC
4. Expansion: |Ψ⟩ABC = (α|0⟩A + β|1⟩A) ⊗ (|00⟩BC + |11⟩BC)/√2
5. Full form: |Ψ⟩ABC = (α|000⟩ + α|011⟩ + β|100⟩ + β|111⟩)/√2
6. This state contains correlations enabling teleportation ∎

Bell基测量的协议

引理 T3-4.2(Bell基测量分解)

BellBasisMeasurementDecomposition : Prop ≡
∀stateABC : CompositeState .
BellMeasurement(stateABC, sitesAB) →
stateABC = ∑k pk|Φk⟩AB ⊗ |ψk⟩C

where
BellMeasurement : Measurement in Bell basis {|Φ±⟩, |Ψ±⟩}
|Φk⟩AB : Bell state measured at sites A,B
|ψk⟩C : Corresponding state at site C
pk : Probability of measuring k-th Bell state (pk = 1/4)

证明

Proof of Bell measurement decomposition:
1. Initial state: |Ψ⟩ABC = (α|000⟩ + α|011⟩ + β|100⟩ + β|111⟩)/√2

2. Rewrite in Bell basis for AB:
|00⟩AB = (|Φ+⟩AB + |Φ-⟩AB)/√2
|01⟩AB = (|Ψ+⟩AB + |Ψ-⟩AB)/√2
|10⟩AB = (|Ψ+⟩AB - |Ψ-⟩AB)/√2
|11⟩AB = (|Φ+⟩AB - |Φ-⟩AB)/√2

3. Substitution yields:
|Ψ⟩ABC = (1/2)[|Φ+⟩AB ⊗ (α|0⟩C + β|1⟩C) +
|Φ-⟩AB ⊗ (α|0⟩C - β|1⟩C) +
|Ψ+⟩AB ⊗ (α|1⟩C + β|0⟩C) +
|Ψ-⟩AB ⊗ (α|1⟩C - β|0⟩C)]

4. Each Bell measurement outcome occurs with probability 1/4
5. Charlie's state depends on Alice's measurement result ∎

经典信息传输约束

引理 T3-4.3(经典通信时间延迟)

ClassicalCommunicationDelay : Prop ≡
∀measurementResult : ClassicalBits . ∀siteA, siteC : Location .
Distance(siteA, siteC) = d →
TransmissionTime(measurementResult, siteA, siteC) ≥ d/c

where
ClassicalBits : 2-bit measurement outcome encoding Bell state
Distance : Spatial separation between sites
c : Speed of light (maximum information transmission speed)
TransmissionTime : Time required for classical information transfer

证明

Proof of communication delay constraint:
1. By D1-4: Time metric requires causal ordering
2. Alice's measurement yields 2 classical bits: (i,j) ∈ {0,1}²
3. Information cannot travel faster than light: v ≤ c
4. Minimum transmission time: Δt = d/c
5. Charlie cannot apply correction before receiving information
6. This delay ensures no faster-than-light communication ∎

幺正修正操作的应用

引理 T3-4.4(状态修正映射)

UnitaryCorrection : Prop ≡
∀measurementOutcome : BellBasisResult . ∀stateC : StateVector .
CorrectionOperation(measurementOutcome) =
match measurementOutcome with
| |Φ+⟩ → I (identity)
| |Φ-⟩ → σz (Pauli-Z)
| |Ψ+⟩ → σx (Pauli-X)
| |Ψ-⟩ → σy (Pauli-Y)

where
CorrectionOperation : Unitary operation applied to site C
I, σx, σy, σz : Pauli operators and identity

证明

Proof of correction operation mapping:
1. From Bell measurement decomposition:
- |Φ+⟩AB measurement → |ψ⟩C = α|0⟩ + β|1⟩ (no correction needed)
- |Φ-⟩AB measurement → |ψ⟩C = α|0⟩ - β|1⟩ (phase flip: σz)
- |Ψ+⟩AB measurement → |ψ⟩C = α|1⟩ + β|0⟩ (bit flip: σx)
- |Ψ-⟩AB measurement → |ψ⟩C = α|1⟩ - β|0⟩ (bit+phase flip: σy)

2. Verification of corrections:
- σz(α|0⟩ - β|1⟩) = α|0⟩ + β|1⟩ = |ψ⟩original
- σx(α|1⟩ + β|0⟩) = α|0⟩ + β|1⟩ = |ψ⟩original
- σy(α|1⟩ - β|0⟩) = -i(α(-i|0⟩) - β(i|1⟩)) = α|0⟩ + β|1⟩

3. All corrections restore original state perfectly ∎

传输保真度验证

引理 T3-4.5(完美传输保真度)

PerfectTeleportationFidelity : Prop ≡
∀ψoriginal : StateVector . ∀ψfinal : StateVector .
TeleportationProtocol(ψoriginal) = ψfinal →
Fidelity(ψoriginal, ψfinal) = |⟨ψoriginal|ψfinal⟩|² = 1

where
TeleportationProtocol : Complete teleportation process
Fidelity : Quantum state overlap measure

证明

Proof of perfect fidelity:
1. Original state: |ψ⟩original = α|0⟩ + β|1⟩
2. After teleportation: |ψ⟩final = α|0⟩ + β|1⟩ (after correction)
3. Inner product: ⟨ψoriginal|ψfinal⟩ = |α|² + |β|² = 1
4. Fidelity: F = |⟨ψoriginal|ψfinal⟩|² = 1² = 1
5. Perfect fidelity achieved in ideal conditions
6. Original state at site A is destroyed (no-cloning) ∎

主定理证明

定理:量子隐形传态实现

MainTheorem : Prop ≡
QuantumTeleportationRealization

证明

Proof of quantum teleportation realization:
Given: Unknown quantum state |ψ⟩A and entangled resource |Φ+⟩BC

1. By Lemma T3-4.1: Construct composite state |Ψ⟩ABC
2. By Lemma T3-4.2: Alice measures AB in Bell basis
3. By Lemma T3-4.3: Classical result transmitted to Charlie
4. By Lemma T3-4.4: Charlie applies appropriate correction
5. By Lemma T3-4.5: Perfect fidelity achieved

Teleportation sequence:
a) Preparation: |ψ⟩A ⊗ |Φ+⟩BC
b) Bell measurement: projects onto |Φk⟩AB ⊗ |ψk⟩C
c) Classical communication: 2 bits from A to C
d) Unitary correction: U_k|ψk⟩C = |ψ⟩C
e) Result: Perfect transfer |ψ⟩A → |ψ⟩C

Therefore: Quantum teleportation is necessarily realizable in self-referential systems ∎

机器验证检查点

检查点1:初始态构造验证

def verify_initial_state_construction():
"""验证初始态构造"""
import numpy as np

# 未知态
alpha, beta = 0.6, 0.8
psi_unknown = np.array([alpha, beta])

# 纠缠资源
bell_state = np.array([1, 0, 0, 1]) / np.sqrt(2) # |Φ+⟩ = (|00⟩ + |11⟩)/√2

# 构造三粒子复合态
# |ψ⟩A ⊗ |Φ+⟩BC
composite_state = np.kron(psi_unknown, bell_state)

# 验证维度
assert composite_state.shape[0] == 8, "Composite state should be 8-dimensional"

# 验证归一化
norm = np.vdot(composite_state, composite_state).real
assert abs(norm - 1.0) < 1e-10, "Composite state should be normalized"

# 验证分量结构
expected = np.array([
alpha/np.sqrt(2), # α|000⟩
0, # |001⟩
0, # |010⟩
alpha/np.sqrt(2), # α|011⟩
beta/np.sqrt(2), # β|100⟩
0, # |101⟩
0, # |110⟩
beta/np.sqrt(2) # β|111⟩
])

assert np.allclose(composite_state, expected), "Composite state components should match expected values"

return True

检查点2:Bell测量协议验证

def verify_bell_measurement_protocol():
"""验证Bell基测量协议"""
import numpy as np

def bell_basis():
"""构造Bell基"""
phi_plus = np.array([1, 0, 0, 1]) / np.sqrt(2) # |Φ+⟩
phi_minus = np.array([1, 0, 0, -1]) / np.sqrt(2) # |Φ-⟩
psi_plus = np.array([0, 1, 1, 0]) / np.sqrt(2) # |Ψ+⟩
psi_minus = np.array([0, 1, -1, 0]) / np.sqrt(2) # |Ψ-⟩
return [phi_plus, phi_minus, psi_plus, psi_minus]

def decompose_in_bell_basis(composite_state):
"""将复合态分解到Bell基"""
bell_states = bell_basis()
coefficients = []
charlie_states = []

# 提取AB子系统和C子系统的对应关系
# 这里简化为直接验证测量概率
for i, bell_state in enumerate(bell_states):
# 构造对应的投影算符 (在AB空间)
projector_AB = np.kron(np.outer(bell_state, bell_state.conj()), np.eye(2))

# 计算投影概率
prob = np.vdot(composite_state, projector_AB @ composite_state).real
coefficients.append(prob)

return coefficients

# 测试态
alpha, beta = 0.6, 0.8
psi_unknown = np.array([alpha, beta])
bell_resource = np.array([1, 0, 0, 1]) / np.sqrt(2)
composite_state = np.kron(psi_unknown, bell_resource)

# 分解到Bell基
probabilities = decompose_in_bell_basis(composite_state)

# 验证概率和为1
total_prob = sum(probabilities)
assert abs(total_prob - 1.0) < 1e-10, "Bell measurement probabilities should sum to 1"

# 验证各概率相等(对称性)
for prob in probabilities:
assert abs(prob - 0.25) < 1e-10, "Each Bell measurement outcome should have probability 1/4"

return True

检查点3:经典信息传输验证

def verify_classical_information_transmission():
"""验证经典信息传输"""
import numpy as np

def encode_measurement_result(bell_state_index):
"""编码测量结果为经典比特"""
# Bell态索引到经典比特的映射
encoding_map = {
0: (0, 0), # |Φ+⟩ → 00
1: (0, 1), # |Φ-⟩ → 01
2: (1, 0), # |Ψ+⟩ → 10
3: (1, 1) # |Ψ-⟩ → 11
}
return encoding_map[bell_state_index]

def transmission_delay(distance, speed_of_light=1.0):
"""计算传输延迟"""
return distance / speed_of_light

# 测试所有可能的测量结果
for bell_index in range(4):
classical_bits = encode_measurement_result(bell_index)

# 验证编码
assert len(classical_bits) == 2, "Should encode to 2 classical bits"
assert all(bit in [0, 1] for bit in classical_bits), "Bits should be 0 or 1"

# 验证传输延迟
distances = [1.0, 10.0, 100.0]
for d in distances:
delay = transmission_delay(d)
assert delay >= 0, "Transmission delay should be non-negative"
assert delay >= d, "Delay should respect speed limit"

# 验证信息容量
total_outcomes = 4 # 4个可能的Bell态
information_content = np.log2(total_outcomes)
assert abs(information_content - 2.0) < 1e-10, "Should carry exactly 2 bits of information"

return True

检查点4:幺正修正操作验证

def verify_unitary_correction_application():
"""验证幺正修正操作"""
import numpy as np

# Pauli算符
I = np.eye(2)
sigma_x = np.array([[0, 1], [1, 0]])
sigma_y = np.array([[0, -1j], [1j, 0]])
sigma_z = np.array([[1, 0], [0, -1]])

def get_correction_operator(bell_outcome):
"""根据Bell测量结果获取修正算符"""
corrections = {
0: I, # |Φ+⟩ → I
1: sigma_z, # |Φ-⟩ → σz
2: sigma_x, # |Ψ+⟩ → σx
3: sigma_y # |Ψ-⟩ → σy
}
return corrections[bell_outcome]

def get_charlie_state_after_measurement(bell_outcome, alpha, beta):
"""获取测量后Charlie的状态"""
states = {
0: np.array([alpha, beta]), # α|0⟩ + β|1⟩
1: np.array([alpha, -beta]), # α|0⟩ - β|1⟩
2: np.array([beta, alpha]), # α|1⟩ + β|0⟩ → β|0⟩ + α|1⟩
3: np.array([beta, -alpha]) # α|1⟩ - β|0⟩ → β|0⟩ - α|1⟩
}
return states[bell_outcome]

# 测试所有修正操作
alpha, beta = 0.6, 0.8
target_state = np.array([alpha, beta])

for bell_outcome in range(4):
# 获取测量后的状态
charlie_state = get_charlie_state_after_measurement(bell_outcome, alpha, beta)

# 应用修正操作
correction = get_correction_operator(bell_outcome)
corrected_state = correction @ charlie_state

# 验证修正后状态等于目标状态
assert np.allclose(corrected_state, target_state), \
f"Correction for outcome {bell_outcome} should restore target state"

# 验证修正算符的幺正性
assert np.allclose(correction @ correction.conj().T, I), \
f"Correction operator {bell_outcome} should be unitary"

# 验证修正算符的Hermitian性(对于Pauli算符)
assert np.allclose(correction, correction.conj().T), \
f"Pauli operator {bell_outcome} should be Hermitian"

return True

检查点5:隐形传态保真度验证

def verify_teleportation_fidelity():
"""验证隐形传态保真度"""
import numpy as np

def teleportation_fidelity(original_state, final_state):
"""计算传输保真度"""
overlap = np.vdot(original_state, final_state)
return abs(overlap)**2

def simulate_teleportation(original_state):
"""模拟完整的隐形传态过程"""
# 假设所有测量结果等概率出现
bell_outcomes = [0, 1, 2, 3]
corrections = [
np.eye(2), # I
np.array([[1, 0], [0, -1]]), # σz
np.array([[0, 1], [1, 0]]), # σx
np.array([[0, -1j], [1j, 0]]) # σy
]

# 模拟每种可能的测量结果
fidelities = []
for outcome in bell_outcomes:
# 根据Bell测量结果确定Charlie的初始状态
alpha, beta = original_state[0], original_state[1]
if outcome == 0:
charlie_state = np.array([alpha, beta])
elif outcome == 1:
charlie_state = np.array([alpha, -beta])
elif outcome == 2:
charlie_state = np.array([beta, alpha])
else: # outcome == 3
charlie_state = np.array([beta, -alpha])

# 应用修正操作
final_state = corrections[outcome] @ charlie_state

# 计算保真度
fidelity = teleportation_fidelity(original_state, final_state)
fidelities.append(fidelity)

return fidelities

# 测试不同的输入态
test_states = [
np.array([1, 0]), # |0⟩
np.array([0, 1]), # |1⟩
np.array([1, 1])/np.sqrt(2), # |+⟩
np.array([1, -1])/np.sqrt(2), # |-⟩
np.array([0.6, 0.8]) # 一般态
]

for original_state in test_states:
fidelities = simulate_teleportation(original_state)

# 验证每种情况都达到完美保真度
for i, fidelity in enumerate(fidelities):
assert abs(fidelity - 1.0) < 1e-10, \
f"Teleportation fidelity should be 1.0 for outcome {i}, got {fidelity}"

# 验证平均保真度
avg_fidelity = np.mean(fidelities)
assert abs(avg_fidelity - 1.0) < 1e-10, \
"Average teleportation fidelity should be 1.0"

# 验证no-cloning:原态被破坏
# 这通过Bell测量的投影性质自动保证

return True

自指完备性的体现

推论 T3-4.1(信息传输的自指约束)

SelfReferentialTeleportationConstraint : Prop ≡
QuantumTeleportationRealization →
∀ψ : StateVector .
InformationContent(ψ) = InformationContent(TeleportedState(ψ)) ∧
NoCloning(ψ) ∧ ClassicalChannelRequired(ψ)

where
InformationContent : Quantum information measure
NoCloning : Original state destroyed during process
ClassicalChannelRequired : 2 classical bits must be transmitted

证明

Proof of self-referential constraints:
1. Information conservation: Quantum information perfectly preserved
2. No-cloning enforcement: Bell measurement destroys original
3. Classical communication: Required to complete protocol
4. Causal structure: Respects relativistic constraints
5. Self-reference maintained: System describes its own information transfer ∎

形式化验证状态

  • 定理语法正确
  • 初始态构造完整
  • Bell测量协议形式化
  • 经典信息传输约束
  • 幺正修正操作验证
  • 传输保真度证明
  • 最小完备