Related Experiment Video
Updated: Jan 27, 2026

Gradient Echo Quantum Memory in Warm Atomic Vapor
Published on: November 11, 2013
Arrow of time and its reversal on the IBM quantum computer
G B Lesovik1, I A Sadovskyy2, M V Suslov1
1Moscow Institute of Physics and Technology, Institutskii per. 9, Dolgoprudny, 141700, Moscow District, Russia.
Abstract:
Uncovering the origin of the "arrow of time" remains a fundamental scientific challenge. Within the framework of statistical physics, this problem was inextricably associated with the Second Law of Thermodynamics, which declares that entropy growth proceeds from the system's entanglement with the environment. This poses a question of whether it is possible to develop protocols for circumventing the irreversibility of time and if so to practically implement these protocols. Here we show that, while in nature the complex conjugation needed for time reversal may appear exponentially improbable, one can design a quantum algorithm that includes complex conjugation and thus reverses a given quantum state. Using this algorithm on an IBM quantum computer enables us to experimentally demonstrate a backward time dynamics for an electron scattered on a two-level impurity.
Related Concept Videos
Quantum Numbers
The Quantum-Mechanical Model of an Atom
Diode: Reverse bias
Reversible and Irreversible Processes
Modeling of Diode Reverse Characteristics
When a reverse voltage applied to a Zener diode exceeds its breakdown voltage, the diode enters the breakdown region. At this point, the...
Entropy Change in Reversible Processes
The statement can be further generalized to prove that entropy is a state function. Take a cyclic process between any two points on a p-V diagram.

