approach without treating the electron phonon coupling as a perturbation. We have derived an expression for the full density matrix or the dot population and discuss it in detail for different values of the coupling strength and the tunneling rate. We derive an expression for the current to see the effects of the coupling of the electrons to the oscillator on the dot and the tunneling rate of electrons to resolve the dynamics of the nanomechanical oscillator. This confirms that electrons resolve the dynamics of nanomechanical oscillator in the regime τ$_{e}$ > τ$_{Osc}$ while they do not in the opposite case τ$_{e}$ > τ$_{Osc}$. Furthermore, we discuss the average energy transferred to oscillator as a function of time. We also discuss the Fano factor as a function of time, which shows thermal behavior and poissonian to non- thermal and super-poissonian behavior. We have found new dynamics of the nanomechanical oscillator: pure and mixed states, which are never present in a classical oscillator. These results suggest further experiments for NEMS to go beyond the classical dynamics. The particle current I$_{α}$ into the interacting region from the lead is related to the expec- tation value of the time derivative of the number operator N$_{α}$ = ∑ αj c † $_{αj}$c$_{αj}$ , as 25,35–37 where we have the following relations where g r, ( a ) , ( < ) α,α ( t, t $^{′}$) refers to the unperturbed states of the leads and given as 18 g r $_{α,α}$( t, t $^{′}$) = 1 N ∑ j g r $_{α,j}$( t, t $^{′}$) = − i n$_{α}$θ ( t − t $^{′}$)$^{+}$$^{∞}$ ∫ −∞ d ε$_{α}$ exp[ − i ε$_{α}$ ( t − t $^{′}$)] , G < $_{o,α}$( t, t ) = ∫ d t ′ { G r 0 , $_{0}$( t, t $^{′}$) V$_{0}$$_{,α}$ ( t $^{′}$) g < $_{α,α}$( t $^{′}$, t ) + G < 0 , $_{0}$( t, t $^{′}$) V$_{0}$$_{,α}$ ( t $^{′}$) g a $_{α,α}$( t $^{′}$, t ) } (A3) G < α, $_{0}$( t, t ) = d t ′ g r $_{α,α}$( t, t $^{′}$) V$_{α,}$$_{0}$ ( t $^{′}$) G < 0 , $_{0}$( t $^{′}$, t ) + g < $_{α,α}$( t, t $^{′}$) V$_{α,}$$_{0}$ ( t $^{′}$) G a 0 , $_{0}$( t $^{′}$, t ) , (A4) I$_{α}$ ( t ) = e ℏ { G < 0 $_{,α}$( t, t ) V$_{α,}$$_{0}$ ( t ) − V ∗ 0 $_{,α}$( t ) G < α, $_{0}$( t, t ) } , (A2) I$_{α}$ ( t ) = − e 〈 d dt x 〉 = − i e ℏ 〈 [ H, x ] 〉 (A1) Appendix A: