Quantum Correlations in Time Domain

Quantum correlations have a very fundamental significance in the field of quantum computation and quantum information theory. Though it is very well defined in the study of spatially separated systems, quantum mechanics allows for the full range of correlation between temporally separated systems too. In this project, our aim is to study it's notion in the time domain. Recently Joseph F. Fitzsimon et al. has given a new approach to the study of quantum correlation in the time domain by introducing the concept of Pseudo-Density Matrix (PDM) whereas, a very fundamental development on the temporal correlation has been done by Legget- Garg in 1985( which can't be accounted by any macro-realist theory). Here, we set out to understand the PDM notion for different cases and the significance of it to hold the correlations in time domain using a quantifying tool. This study is extended to find out the correspondences or incompatibility of it with Legget-Garg inequality and Concurrence - a measure of quantum entanglement.