collaborators

7 papers

quant-ph2025

Hamiltonian characterisation of multi-time processes with classical memory

Kaumudibikash Goswami, Abhinash Kumar Roy, Varun Srivastava +4

A central problem in open quantum systems is the characterization of non-Markovian processes, where an environment retains the memory of its interaction with the system. A key dist…

quant-ph2025

Entropic limitations on fixed causal order

Matheus Capela, Kaumudibikash Goswami

Quantum processes can exhibit scenarios beyond a fixed order of events. We propose information inequalities that, when violated, constitute sufficient conditions to certify quantum…

quant-ph2025

Maximum and minimum causal effects of physical processes

Giulio Chiribella, Kaumudibikash Goswami

We introduce two quantitative measures of the strength of causal relations in quantum theory and more general physical theories. These two measures, called the maximum and minimum…

quant-ph2025

Causal and Non-Causal Revivals of Information: A New Regime of Non-Markovianity in Quantum Stochastic Processes

Francesco Buscemi, Rajeev Gangwar, Kaumudibikash Goswami +5

The study of information revivals, witnessing the violation of certain data-processing inequalities, has provided an important paradigm in the study of non-Markovian quantum stocha…

quant-ph2025

Squashed quantum non-Markovianity: a measure of genuine quantum non-Markovianity in states

Rajeev Gangwar, Tanmoy Pandit, Kaumudibikash Goswami +2

Quantum non-Markovianity in tripartite quantum states represents a correlation between systems and when conditioned on the system and is known to have both c…

quant-ph2024

Conditional entropy and information of quantum processes

Siddhartha Das, Kaumudibikash Goswami, Vivek Pandey

What would be a reasonable definition of the conditional entropy of bipartite quantum processes, and what novel insight would it provide? We develop this notion using four informat…