How many bits specify a quantum state?

Abstract

Quantum mechanics suggests that nature is discrete, with one state per phase space volume ${\hslash }^{3N}$. This appears to contradict the idea that the state of an N-particle system can have infinite precision and is described by a set of exponentially many complex numbers. Using a finite-temperature gas confined in a box as an example, this short paper argues that there are indeed limits to the precision of wave functions, and that this may help at understanding the quantum-to-classical transition.

Short, easy-to-read paper; abstract rewritten; one reference added

References in corpus (3)

• Equilibration, thermalisation, and the emergence of statistical mechanics in closed quantum systems
• Strong measurements give a better direct measurement of the quantum wave function
• Teleportation of entanglement over 143 km

Cited by in corpus (1)

• Connecting the quantum and classical worlds