collaborators

5 papers

quant-ph2025

A perturbation theory for multi-time correlation functions in open quantum systems

Piotr Szańkowski

Dynamical maps are the principal subject of the open system theory. Formally, the dynamical map of a given open quantum system is a density matrix transformation that takes any ini…

quant-ph2025

Phenomenological quantum mechanics: II. Deducing the formalism from experimental observations

Piotr Szańkowski, Piotr Szańkowski, Davide Lonigro +5

We propose an exercise in which one attempts to deduce the formalism of quantum mechanics solely from phenomenological observations. The only assumed inputs are the multi-time prob…

quant-ph2025

Phenomenological quantum mechanics: I. Phenomenology of quantum observables

Piotr Szańkowski, Piotr Szańkowski, Davide Lonigro +5

We propose an exercise in which one attempts to deduce the formalism of quantum mechanics solely from phenomenological observations. The only assumed inputs are obtained through se…

quant-ph2024

Double or nothing: a Kolmogorov extension theorem for multitime (bi)probabilities in quantum mechanics

Davide Lonigro, Fattah Sakuldee, Łukasz Cywiński +2

The multitime probability distributions obtained by repeatedly probing a quantum system via the measurement of an observable generally violate Kolmogorov's consistency property. Th…

quant-ph2024

Objectivity of classical quantum stochastic processes

Piotr Szańkowski, Łukasz Cywiński

We investigate what can be concluded about a quantum system when sequential quantum measurements of its observable -- a prominent example of the so-called quantum stochastic proces…