Could second quantisation and QFT become a problem when scaling up quantum computers?

Question

So I was wondering about the following:

I can encode an algorithm in position $hat x$ in quantum mechanics.
However, in QFT position is not an operator it becomes a parameter $x$.

Has anyone expressed concern that quantum field theory (QFT) will become relevant in the scale-up when creating a quantum computer and thus one should be careful about the second quantization of operators?

Jonathan Trousdale · Accepted Answer

QFT (more specifically QED) is already at the heart of quantum computation.  Second quantization formalism is used even in constructing toy models for quantum computers (see e.g., Section 7.3.2 of Nielsen and Chuang).

Many of the rapid advances in superconducting quantum processors over the past decade can be attributed to the introduction of circuit Quantum Electrodynamics (cQED, introduced here and here, full exposition, lecture notes), and the closely related introduction of the transmon (here).  As suggested by the nomenclature these architectures are built on QED rather than non-relativistic QM.

Could second quantisation and QFT become a problem when scaling up quantum computers?

One Answer

Add your own answers!

Ask a Question