def test_local_hamiltonians_3(self):
Sx1, Sy1, Sz1 = N_body_spins(0.5, 1, 3)
Sx2, Sy2, Sz2 = N_body_spins(0.5, 2, 3)
Sx3, Sy3, Sz3 = N_body_spins(0.5, 3, 3)
Sx12, Sy12, Sz12 = N_body_spins(0.5, 1, 2)
Sx22, Sy22, Sz22 = N_body_spins(0.5, 2, 2)
mps = self.mps_0_3
listH = [Sz12@Sz22+Sx12, Sz12@Sz22+Sx12+Sx22]
fullH = sum([n_body(a, i, len(listH), d=2) for i, a in enumerate(listH)], axis=0)
self.assertTrue(mps.dA_dt(listH, fullH=False)==mps.dA_dt(fullH, fullH=True))
def test_local_recombine(self):
Sx1, Sy1, Sz1 = N_body_spins(0.5, 1, 4)
Sx2, Sy2, Sz2 = N_body_spins(0.5, 2, 4)
Sx3, Sy3, Sz3 = N_body_spins(0.5, 3, 4)
Sx4, Sy4, Sz4 = N_body_spins(0.5, 4, 4)
Sx12, Sy12, Sz12 = N_body_spins(0.5, 1, 2)
Sx22, Sy22, Sz22 = N_body_spins(0.5, 2, 2)
listH4 = [Sz12@Sz22+Sx12, Sz12@Sz22+Sx12+Sx22, Sz12@Sz22+Sx22]
comH4 = sum([n_body(a, i, len(listH4), d=2) for i, a in enumerate(listH4)], axis=0)
fullH4 = Sz1@Sz2+Sz2@Sz3+Sz3@Sz4+Sx1+Sx2+Sx3+Sx4
self.assertTrue(allclose(fullH4, comH4))
def test_local_hamiltonians_7(self):
Sx1, Sy1, Sz1 = N_body_spins(0.5, 1, 7)
Sx2, Sy2, Sz2 = N_body_spins(0.5, 2, 7)
Sx3, Sy3, Sz3 = N_body_spins(0.5, 3, 7)
Sx4, Sy4, Sz4 = N_body_spins(0.5, 4, 7)
Sx5, Sy5, Sz5 = N_body_spins(0.5, 5, 7)
Sx6, Sy6, Sz6 = N_body_spins(0.5, 6, 7)
Sx7, Sy7, Sz7 = N_body_spins(0.5, 7, 7)
Sx12, Sy12, Sz12 = N_body_spins(0.5, 1, 2)
Sx22, Sy22, Sz22 = N_body_spins(0.5, 2, 2)
mps = self.mps_0_7
listH = [Sz12@Sz22+Sx12, Sz12@Sz22+Sx12+Sx22, Sz12@Sz22+Sx12+Sx22, Sz12@Sz22+Sx12+Sx22, Sz12@Sz22+Sx12+Sx22, Sz12@Sz22+Sx22]
fullH = sum([n_body(a, i, len(listH), d=2) for i, a in enumerate(listH)], axis=0)
self.assertTrue(mps.dA_dt(listH, fullH=False)==mps.dA_dt(fullH, fullH=True))
def test_random_with_energy(self):
Sx12, Sy12, Sz12 = N_body_spins(0.5, 1, 2)
Sx22, Sy22, Sz22 = N_body_spins(0.5, 2, 2)
L = 6
d = 2
D = 1
h = 4*Sz12@Sz22+2*Sx22+2*Sz22
h = (h+h.conj().T)/2
H = [h for _ in range(L-1)]
H[0] = H[0]+2*Sx12+2*Sz12
comH = sum([n_body(a, i, len(H), d=2) for i, a in enumerate(H)], axis=0)
v = eigvalsh(comH)
E = (max(v)-min(v))/2.5
tol = 1e-10
mps = fMPS().random_with_energy_E(E, H, L, d, D, 1e-10)
self.assertTrue(abs(mps.energy(H)-E)<tol)