QUANTUM CARPETS MADE SIMPLE1

Michael Berry, Irene Marzoli, Wolfgang P. Schleich

Lei Shi

How is the world made up? So far, there is no good explanation. Based on the point model of the world, the quantum model is made by logical reasoning. Several thought experiment about perception are made to explain how physical quantities such as time and space emerge. Here we show that a dividing, decaying, and rotating point can build a colorful world.

E. Bagán, S. Iblisdir, R. Muñoz-Tapia

We address the problem of measuring the relative angle between two ``quantum axes'' made out of ${N}_{1}$ and ${N}_{2}$ spins. Closed forms of our fidelitylike figure of merit are obtained for an arbitrary number of parallel spins. The asymptotic regimes of large ${N}_{1}$ and/or ${N}_{2}$ are discussed in detail. The extension of the concept ``quantum axis'' to more general situations is addressed. We give optimal strategies when the first quantum axis is made out of parallel spins whereas the second is a general state made out of two spins.

Paul Halpern

Richard Goodman

Distinctions Made Linear: A Machine-Checked Unification of Classical and Quantum Logical Entropy