Born Approximation

The Born Approximation assumes that $\forall t\in {\mathbb{R}}_0^{+}$the Density Operator ${\rho }_t$ can be written as a Tensor product between the Reduced system ${\rho }_S$ and the Thermal bath component ${\rho }_b$, such that ${\rho }_t={\rho }_S⨂{\rho }_b=\mathrm{Tr}[{\rho }_t]⨂{\rho }_b$.

Since we are working with a Thermal bath, Decoherence Times are short, quickly leading to dissipation, which justifies the assumption in the Born Approximation.

🌍 Useful resources

• Section 1.4 of A Born-Markov master equation approach to correlated quantum systems in non-equilibrium .