constants_from_initial_conditions

kerrgeopy.initial_conditions.constants_from_initial_conditions(a, initial_position, initial_velocity)

Computes the constants of motion \((\mathcal{E},\mathcal{L},\mathcal{Q})\) of the orbit with the given initial conditions.

Parameters:

• a (double) – spin parameter

• initial_position (tuple(double,double,double,double)) – initial position \((t_0,r_0,\theta_0,\phi_0)\)

• initial_velocity (tuple(double,double,double,double)) – initial four-velocity \((u^t_0,u^r_0,u^\theta_0,u^\phi_0)\)

Returns:

tuple of constants of motion \((\mathcal{E},\mathcal{L},\mathcal{Q})\)

Return type:

tuple(double,double,double)