()
return (T1, T2)
Returns a tuple (T1,T2) of unique operators.
Returns a tuple (T1,T2) of unique operators.
Returns a tuple ( T1 T2 ) of unique operators .
def get_CC_operators():
    """
    Returns a tuple (T1,T2) of unique operators.
    """
    i = symbols('i', below_fermi=True, cls=Dummy)
    a = symbols('a', above_fermi=True, cls=Dummy)
    t_ai = AntiSymmetricTensor('t', (a,), (i,))
    ai = NO(Fd(a)*F(i))
    i, j = symbols('i,j', below_fermi=True, cls=Dummy)
    a, b = symbols('a,b', above_fermi=True, cls=Dummy)
    t_abij = AntiSymmetricTensor('t', (a, b), (i, j))
    abji = NO(Fd(a)*Fd(b)*F(j)*F(i))

    T1 = t_ai*ai
    T2 = Rational(1, 4)*t_abij*abji
    return (T1, T2)
def get_CC_operators ( ) : i = symbols ( 'i' , below_fermi = True , cls = Dummy ) a = symbols ( 'a' , above_fermi = True , cls = Dummy ) t_ai = AntiSymmetricTensor ( 't' , ( a , ) , ( i , ) ) ai = NO ( Fd ( a ) * F ( i ) ) i , j = symbols ( 'i,j' , below_fermi = True , cls = Dummy ) a , b = symbols ( 'a,b' , above_fermi = True , cls = Dummy ) t_abij = AntiSymmetricTensor ( 't' , ( a , b ) , ( i , j ) ) abji = NO ( Fd ( a ) * Fd ( b ) * F ( j ) * F ( i ) ) T1 = t_ai * ai T2 = Rational ( 1 , 4 ) * t_abij * abji return ( T1 , T2 )