Quantum dynamics on your laptop? New technique moves us closer

Reading their paper, it does seem like this method is significantly simpler than using something like MPS, my main concern is the practical coupling regime for which this method works, I would imagine that it would fail closer to critical points in theories with phase transitions?

I'm curious, are any quantum simulators accessible to sort of hobbyists?

I have a background in solid state physics from coursework, but I've never really used QM for almost anything outside of school.

I think you will have best luck by searching for "open quantum systems" toolboxes in your language of choice. My preferences are, in order:

- QuantumOptics.jl in Julia

- QuantumToolbox.jl in Julia

- qutip in python

These are all "just" nice domain specific wrappers around linear algebra and differential equation tools. They do the "silly" exponentially expensive simulation technique that works for any quantum system. If you are interested in efficient (not exponential) simulation techniques that support only a subset of all quantum dynamics try out:

- stabilizer formalism (e.g. for error correction) with QuantumClifford.jl or stim

- Gaussian quantum optics (e.g. for laser physics) with Gabs.jl

- tensor networks (e.g. for arbitrary low-rank entanglement) with ITensors.jl

This is a nice practical technique for open quantum systems with relatively low entanglement. The introduction lays out exactly what regime they're aiming at: 1. Affordable (laptop scale) 2. Captures "sufficient" quantum effects (low entanglement regime; you accurately can't simulate a quantum computer with this) 3. Straightforward to implement. From a cursory glance, it does all three. I'm slightly surprised that TWA hasn't been applied to open systems extensively before, but it was always a relatively obscure technique. I'm guessing this should be quite useful in practice for e.g. AMO and cavity systems with relatively large dissipation terms that prevent entanglement build up. However, I'd guess this wouldn't do very well near phase transitions. All-in-all, a nice new technique for a regime that didn't have too many options.

Thanks a lot!

With _quantum_ phase transitions, yes.

Yeah this seems like a very useful technique for ground state properties, I’m also surprised in retrospect, having never heard of TWA before now.

If you prefer python, tenpy is quite nice for tensor networks as well.

Not perfectly answering your request, but did you look at https://github.com/topics/quantum-computing?o=desc&s=updated

Thanks! I am kind of stuck in Python, or at least stuck outside of Julia.

Try ORCA and GROMACS. Accessible as you can DL them and there are lots of docs. But very high learning curve, and not graphical on their own.

Thanks a lot.

I haven't, thanks.