“…As two degrees of freedom (namely, the polar and azimuthal angles , describing the magnetization orientation in configuration space) are involved, the spin Hamiltonian, unlike that of particles, is no longer separable and additive since the governing magnetic Langevin equation is essentially a form of the Larmor equation so that inertial effects play no role here [11,12]. Nevertheless, the role of inertia in the mechanical system is essentially mimicked in the magnetic system for noncircularly symmetric free energy potentials by the gyromagnetic term, which causes coupling or entanglement of We recall that the VLD spin escape rate both with and without STT has already been determined [12,13] either via involved vector manipulation [14] or else via long and complicated calculations with the energy and phase as variables in the magnetic Langevin equation involving multiplicative noise [13,15,16,17]. Both methods ultimately lead to the same energy-controlled-diffusion equation for giant classical spins with quasi-stationary solutions yielding the VLD rate.…”