This seems a little redundant, given my recent 6 month break from blogging, but I’m gone on holidays for three weeks starting in about 36 hours, first for two weeks in New Zealand, and then for one more week’s back in Brisbane, which will mostly be spent attending the Ideas Festival. Should be fun, but I won’t be blogging during that time.

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No problem, but nice to see you back! I’m eagerly awaiting more interesting texts like those from before your break.

Boy, is it quiet, both here and on Bacon’s Quantum Pontiff. Just to stir things up, what do people think of the preprint on the arxiv server this morning:

The Free Will Theorem” http://www.arxiv.org/abs/quant-ph/0604079

Such titles are often associated with fringe physics — except that these particular nutjobs are the mathematicians John Conway and Simon Kochen!

These guys may be nutjobs, but they are high-power nutjobs, and I enjoyed their preprint very much.

In engineering, we tend to think of every quantum problem as an exercise in model order reduction (MOR). But our MOR colleagues (and there are a lot of them — there are more academic articles by far on MOR than on open quantum systems!) always complain that simulation algorithms for open quantum systems are stochastic. “Can’t you eliminate the stochasticity, and make your open quantum system model deterministic?” they complain.

The Conway/Kochen Free Will Theorem answers that question pretty crisply, by showing that open quantum systems have properties that *no* (locally realistic) deterministic simulation can exhibit. And, they prove it in a fun way.

Also, it’s just not right to ignore an article that begins “Do we really have free will, or, as a few determined folk maintain, is it all an illusion? We donâ€™t know, but will prove in this paper that if indeed there exist any experimenters with a modicum of free will, then elementary particles must have their own share of this valuable commodity.”

All the above is just to stimulate some comment!