3 papers
quant-ph2026
Indefinite Causal Order Reverses the Real-Complex Hierarchy
Jacopo Surace, Shintaro Minagawa, Ravi Kunjwal
[Note added after submission. After posting the first version of this preprint and corresponding with Ved Kunte and Kuntal Sengupta, we identified an issue with the claimed separat…
quant-ph2026
Reconstruction of finite Quasi-Probability and Probability from Principles: The Role of Syntactic Locality
Jacopo Surace
Quasi-probabilities appear across diverse areas of physics, but their conceptual foundations remain unclear: they are often treated merely as computational tools, and operations li…
quant-ph2025
On whether quantum theory needs complex numbers: the foil theories perspective
Yìlè Yīng, Maria Ciudad Alañón, Daniel Centeno +5
Recent work by Renou et al. (2021) has led to some controversy concerning the question of whether quantum theory requires complex numbers for its formulation. We promote the view t…