5 papers
No extension of the Quantum Tensor Product admits a Superposition principle
Vincenzo Fiorentino, Kuntal Sengupta
Textbook quantum superposition refers to the feature that certain linear combinations of Hilbert space rays, each representing a valid quantum state, are themselves valid states. T…
How many systems can be dephased before the quantum switch becomes causally definite?
Yassine Benhaj, Kuntal Sengupta, Cyril Branciard
Quantum processes with indefinite causal order -- so-called causally nonseparable processes -- can exhibit various advantages over quantum circuits with a fixed or a well-defined c…
Quantum Nonlocality and Device-Independent Randomness are Robust to Noisy Signaling Channels
Kuntal Sengupta, Lewis Wooltorton
Given a pair of isolated devices that accept random binary inputs and return binary outputs, a user can deduce from the observed data alone if the underlying mechanism can be expla…
Correlation Self-Testing of Quantum Theory against Generalised Probabilistic Theories with Restricted Relabelling Symmetry
Kuntal Sengupta, Mirjam Weilenmann, Roger Colbeck
Correlation self-testing of quantum theory involves identifying a task or set of tasks whose optimal performance can be achieved only by theories that can realise the same set of c…
Achieving Maximal Causal Indefiniteness in a Maximally Nonlocal Theory
Kuntal Sengupta
Quantum theory allows for the superposition of causal orders between operations, i.e., for an indefinite causal order; an implication of the principle of quantum superposition. Sin…