About quantum computer software

TL;DR

This paper discusses the gap between quantum hardware and software, emphasizing the need for new software primitives to effectively control quantum processes beyond traditional gate arrays, and estimates a key constant related to decoherence.

Contribution

It highlights the limitations of current quantum software models and proposes the importance of developing new primitives to better simulate and control quantum processes.

Findings

Current quantum gate arrays are insufficient for effective control.

The decoherence constant can be estimated from quantum electrodynamics and nuclear decay.

Experimental realization of Grover's algorithm provides insights into system limitations.

Abstract

Quantum computer is the key to controlling complex processes. If its hardware, in general is successfully created on the basis of the physical baggage of the 20th century, the mathematical software is fundamentally lagging behind. Feynman's user interface in the form of quantum gate arrays, cannot be used for the control because it gives the solution of Schr\"odinger equation with quadratic slowdown compared to the real process. The software must then imitate the real process using appropriate program primitives written as the programs for classical supercomputer. The decoherence will be reflected by some constant - the number of basic states that can fit into the limited of memory available to software. The real value of this constant can be found in the experimental realization of Grover search algorithm. Rough estimates of this constant are given based on the simplest processes of quantum electrodynamics and nuclear decay.