def testSingletBetweenAlice1AndBobAndLocalOtherwiseIsNotInPolytope(self): scenario = SequentialBellScenario([[2, 2], [2, 2]], [2, 2]) alice1blochVectors = [[1, 0, 0], [0, 1, 0]] alice1Observables = list( map(lambda bloch: createQubitObservable(bloch), alice1blochVectors)) alice1Krauss = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), alice1Observables)) bobUnBlochVectors = [[-1, -1, 0], [-1, 1, 0]] bobObservables = list( map(lambda bloch: createQubitObservable(bloch), bobUnBlochVectors)) bobEffects = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), bobObservables)) psi = createMaxEntState(2) expectedCorrelations = {((x1, x2), y, (a1, a2), b): int( (a2 == 0)) * ((qt.tensor(alice1Krauss[x1][a1], bobEffects[y][b]) * psi * psi.dag()).tr()) for ((x1, x2), y, (a1, a2), b) in scenario.getTuplesOfEvents()} expectedBehaviour = Behaviour(scenario, expectedCorrelations) poly = SequentialBellPolytope(scenario) self.assertFalse(poly.contains(expectedBehaviour.getProbabilityList()))
def testRandProjMeasBetweenAlice1andBob(self): scenario = SequentialBellScenario([[2, 2], [2, 2]], [2, 2]) alice1blochVectors = [[1, 0, 0], [0, 1, 0]] alice1Observables = list( map(lambda bloch: createQubitObservable(bloch), alice1blochVectors)) alice1Krauss = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), alice1Observables)) phases = [ np.random.uniform(-np.pi / 2, np.pi / 2), np.random.uniform(-np.pi / 2, np.pi / 2) ] alice2blochVectors = [[np.sin(theta), 0, np.cos(theta)] for theta in phases] alice2Observables = list( map(lambda bloch: createQubitObservable(bloch), alice2blochVectors)) alice2Effects = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), alice2Observables)) phasesBob = [ np.random.uniform(-np.pi / 2, np.pi / 2), np.random.uniform(-np.pi / 2, np.pi / 2) ] bobVectors = [[np.sin(theta), 0, np.cos(theta)] for theta in phasesBob] bobObservables = list( map(lambda bloch: createQubitObservable(bloch), bobVectors)) bobEffects = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), bobObservables)) aux = alice1Krauss alice1Krauss = alice2Effects alice2Effects = aux psi = createMaxEntState(2) rho = psi * psi.dag() expectedCorrelations = {} for x1 in range(2): for a1 in range(2): postMeasrmntState = qt.tensor( alice1Krauss[x1][a1], qt.qeye(2)) * rho * (qt.tensor( alice1Krauss[x1][a1], qt.qeye(2))).dag() for x2, y, a2, b in product(range(2), repeat=4): expectedCorrelations[(x1, x2), y, (a1, a2), b] = ( qt.tensor(alice2Effects[x2][a2], bobEffects[y][b]) * postMeasrmntState).tr().real expectedBehaviour = Behaviour(scenario, expectedCorrelations) poly = BellPolytopeWithOneWayCommunication( SequentialBellPolytope(scenario)) self.assertTrue(poly.contains(expectedBehaviour.getProbabilityList()), 'phases:' + str(phases[0]) + ', ' + str(phases[1]))
def testCHSHBetweenAlice1AndBobAndIdentityInAlice2IsInPolytope(self): scenario = SequentialBellScenario([[2, 2], [2, 2]], [2, 2]) alice1blochVectors = [[1, 0, 0], [0, 1, 0]] alice1Observables = list( map(lambda bloch: createQubitObservable(bloch), alice1blochVectors)) alice1Krauss = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), alice1Observables)) alice2Effects = [[qt.qeye(2), 0 * qt.qeye(2)], [qt.qeye(2), 0 * qt.qeye(2)]] bobUnBlochVectors = [[-1, -1, 0], [-1, 1, 0]] bobObservables = list( map(lambda bloch: createQubitObservable(bloch), bobUnBlochVectors)) bobEffects = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), bobObservables)) psi = createMaxEntState(2) rho = psi * psi.dag() expectedCorrelations = {} for x1 in range(2): for a1 in range(2): postMeasrmntState = qt.tensor( alice1Krauss[x1][a1], qt.qeye(2)) * rho * (qt.tensor( alice1Krauss[x1][a1], qt.qeye(2))).dag() for x2, y, a2, b in product(range(2), repeat=4): expectedCorrelations[(x1, x2), y, (a1, a2), b] = ( qt.tensor(alice2Effects[x2][a2], bobEffects[y][b]) * postMeasrmntState).tr().real expectedBehaviour = Behaviour(scenario, expectedCorrelations) poly = BellPolytopeWithOneWayCommunication( SequentialBellPolytope(scenario)) self.assertTrue(poly.contains(expectedBehaviour.getProbabilityList()))
alice1outputs = [2, 2] alice2outputs = [2, 2, 3] bobOutputs = [2, 2] scenario = SequentialBellScenario([alice1outputs, alice2outputs], bobOutputs) epsilon = np.pi / 4 - 0.1 plus = 1 / np.sqrt(2) * (qt.basis(2, 0) + qt.basis(2, 1)) minus = 1 / np.sqrt(2) * (qt.basis(2, 0) - qt.basis(2, 1)) Kplus = np.cos(epsilon) * plus * plus.dag() + np.sin( epsilon) * minus * minus.dag() Kminus = -np.cos(epsilon) * minus * minus.dag() + np.sin( epsilon) * plus * plus.dag() alice1Krauss = [ projectorsForQubitObservable(createQubitObservable([0, 0, 1])), [Kplus, Kminus] ] alice2blochVectors = [[0, 0, 1], [1, 0, 0]] alice2Observables = list( map(lambda bloch: createQubitObservable(bloch), alice2blochVectors)) alice2Effects = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), alice2Observables)) trineAlice2 = [[0, 0, 1], [np.sin(2 * np.pi / 3), 0, np.cos(2 * np.pi / 3)], [np.sin(4 * np.pi / 3), 0, np.cos(4 * np.pi / 3)]]
def testMeasurementsOverSeparableStateAreLocal(self): alice1outputs = [2, 2] alice2outputs = [2, 3] bobOutputs = [2, 2] scenario = SequentialBellScenario([alice1outputs, alice2outputs], bobOutputs) epsilon = 0 plus = 1 / np.sqrt(2) * (qt.basis(2, 0) + qt.basis(2, 1)) minus = 1 / np.sqrt(2) * (qt.basis(2, 0) - qt.basis(2, 1)) Kplus = np.cos(epsilon) * plus * plus.dag() + np.sin( epsilon) * minus * minus.dag() Kminus = -np.cos(epsilon) * minus * minus.dag() + np.sin( epsilon) * plus * plus.dag() alice1Krauss = [ projectorsForQubitObservable(createQubitObservable([0, 0, 1])), [Kplus, Kminus] ] alice2blochVectors = [[0, 0, 1]] alice2Observables = list( map(lambda bloch: createQubitObservable(bloch), alice2blochVectors)) alice2Effects = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), alice2Observables)) trineAlice2 = [[0, 0, 1], [np.sin(2 * np.pi / 3), 0, np.cos(2 * np.pi / 3)], [np.sin(4 * np.pi / 3), 0, np.cos(4 * np.pi / 3)]] paulies = [qt.sigmax(), qt.sigmay(), qt.sigmaz()] alice2Effects.append( list( map( lambda bloch: effectForQubitPovm( 1 / 3, sum([paulies[i] * bloch[i] for i in range(3)])), trineAlice2))) mu = np.arctan(np.sin(2 * epsilon)) bobUnBlochVectors = [[np.sin(mu), 0, np.cos(mu)], [-np.sin(mu), 0, np.cos(mu)]] bobObservables = list( map(lambda bloch: createQubitObservable(bloch), bobUnBlochVectors)) bobEffects = list( map( lambda qubitObservable: projectorsForQubitObservable( qubitObservable), bobObservables)) psi = qt.tensor(qt.basis(2, 0), qt.basis(2, 0)) rho = psi * psi.dag() expectedCorrelations = {} for x1, x2, y in product(range(len(alice1outputs)), range(len(alice2outputs)), range(len(bobOutputs))): for a1, a2, b in product(range(alice1outputs[x1]), range(alice2outputs[x2]), range(bobOutputs[y])): postMeasrmntState = qt.tensor( alice1Krauss[x1][a1], qt.qeye(2)) * rho * (qt.tensor( alice1Krauss[x1][a1], qt.qeye(2))).dag() expectedCorrelations[(x1, x2), y, (a1, a2), b] = ( qt.tensor(alice2Effects[x2][a2], bobEffects[y][b]) * postMeasrmntState).tr().real expectedBehaviour = Behaviour(scenario, expectedCorrelations) polytope = BellPolytopeWithOneWayCommunication( SequentialBellPolytope(scenario)) self.assertTrue( polytope.contains(expectedBehaviour.getProbabilityList()))
if __name__ == '__main__': n = 4 outputsAliceSequence = [2 for _ in range(n)] outputsBob = [2 for _ in range(n)] + [3] phi = lambda j: (j - 1) * np.pi / n phiprime = lambda j: (2 * j - 1) * np.pi / (2 * n) psi = createMaxEntState(2) aliceEffects = [ projectorsForQubitObservable( createQubitObservable([np.sin(phi(j)), 0, np.cos(phi(j))])) for j in range(1, n + 1) ] bobEffects = [ projectorsForQubitObservable( createQubitObservable( [np.sin(phiprime(j)), 0, np.cos(phiprime(j))])) for j in range(1, n + 1) ] bobPostMeasurmentStates = [[ 1 / ((qt.tensor(effect, qt.qeye(2)) * psi * psi.dag()).tr()) * (qt.tensor(effect, qt.qeye(2)) * psi).ptrace(1) for effect in measurement ] for measurement in aliceEffects] usdState1 = bobPostMeasurmentStates[0][0]
import numpy as np from _functools import reduce import qutip as qt from bellpolytope import BellPolytope from bellscenario import BellScenario from qutipauxfunc import createQubitObservable, projectorsForQubitObservable,\ effectForQubitPovm, addEffectsForAbortOutcomes, createMaxEntState,\ computeDistributionFromStateAndEffects if __name__ == '__main__': outputsAlice = [3,3,3,3] outputsBob = [3,3,3,5] aliceBlochVectors = [[1,1,1],[1,-1,-1],[-1,1,-1],[-1,-1,1]] aliceObservables = list(map(lambda bloch : createQubitObservable(bloch),aliceBlochVectors)) aliceEffects = list(map(lambda qubitObservable : projectorsForQubitObservable(qubitObservable),aliceObservables)) bobObservables=[qt.sigmax(),qt.sigmay(),qt.sigmaz()] bobEffects = list(map(lambda qubitObservable : projectorsForQubitObservable(qubitObservable),bobObservables)) bobEffects += [list(map(lambda bloch : effectForQubitPovm(1/4, createQubitObservable(bloch)),aliceBlochVectors))] aliceEffects = addEffectsForAbortOutcomes(aliceEffects,2) bobEffects = addEffectsForAbortOutcomes(bobEffects,2) psi=createMaxEntState(2) scenario=BellScenario(outputsAlice,outputsBob) poly = BellPolytope(scenario)