5 papers
Superposition of dynamics, indefinite causal order, and quantum histories
Charis Anastopoulos, Ntina Savvidou
The process-matrix formalism describes quantum processes without assuming a fixed global causal order, but the physical meaning of indefinite causal order remains open. We address…
Beyond the Unruh vacuum: multi-time correlations in black hole collapse and evaporation
Konstantinos Xenos, Charis Anastopoulos, Andreas F. Terzis
The black hole information paradox originates from the thermal character of Hawking radiation, which appears to erase information about the collapsing matter. However, thermality c…
A post-selected quantum model of cosmic acceleration
Dimitris Lionas, Charis Anastopoulos, Konstantinos Gourgouliatos
The origin of cosmic acceleration remains a central problem in cosmology, commonly attributed to a cosmological constant within the CDM model or to dynamical dark energy. Here,…
Quantum field theory measurements for relativistic particles
Nadia Koliopoulou, Charis Anastopoulos, Ntina Savvidou
The formulation of a consistent measurement theory for relativistic quantum fields has become a problem of growing foundational and practical significance. Standard non-relativisti…
Final States in Quantum Cosmology: Cosmic Acceleration as a Quantum Post-Selection Effect
Charis Anastopoulos
Standard quantum theory admits naturally statistical ensembles that are both pre-selected and post-selected, i.e., they involve both an initial and a final state. We argue that the…