Decoherence during time evolution by Schroedinger equation

TL;DR

This paper discusses how decoherence, the loss of quantum interference, occurs during time evolution according to the Schrödinger equation, using a thought experiment involving a hydrogen atom's states.

Contribution

It provides a conceptual analysis of decoherence as loss of interference, relating it to interpretations of quantum mechanics and wavepacket collapse.

Findings

Decoherence corresponds to the loss of interference ability.

Superposition loss can be superficial, not absolute.

Applications to many-worlds interpretation and wavepacket collapse are discussed.

Abstract

A thought experiment is discussed to clarify the concept of decoherence. Superposition of states consisting of ground state of a single hydrogen atom and its excited state after a huge amount of time is discussed to show that the decoherence of the state, more precisely the loss of coherence, is literally the loss of ability of interference. The loss of superposition of states is just apparent or even superfacial. Applications of this example in its relation to many-world interpretation of observation of a quantum state, decoherence in usual cases, and weak collapse of wavepackets are discussed.