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Just to clarify: the problem here is wave collapse. Wave collapse happens at an instant of time, and therefore picks a frame of reference. The wavefunction changes instantaneously over all space when "measurement" occurs, and does not obey the Schrodinger equation (or relativistic equivalent).

The "intriguing development" by Rovelli is that he used decoherence to explain measurement probabilities in some relativistic model. Time still exists in this model (which lives over R^{3+1}), but nothing happens instantaneously. Basically, he showed that the relativistic schrodinger equation gives the same experimental predictions as wave collapse.

Wave collapse hasn't been taken seriously by physicists in years. It's been thoroughly debunked again and again (c.f. http://www.npl.washington.edu/npl/int_rep/tiqm/TI_toc.html, http://www.flownet.com/ron/QM.pdf). The press keeps reporting it because it's such a delicious mystery.

Which physicists? As far as I know, copehnagen is the mainstream ontology.

I gave a talk last week on decoherence, just working out an explicit example where we can almost exactly solve the combined particle/measurement device system. The idea that wave collapse is unnecessary was not uncontroversial.

A quote from before I even gave the talk: "I don't believe you."

> Which physicists?

Well, Cramer (the one I cited) for one. David Mermin. Cerf and Adami. Roland Omnes. John Preskill. How many do you want?

> I gave a talk last week on decoherence

To what audience?

The audience of my talk was mixed math, physics and chemistry with a shared interest in quantum control.

As for the physicists you cite, the ones I recognize seem to work on either quantum information or foundations of QM. Decoherence is far more accepted in these fields than in the rest of physics.

Yeah, well, those are the people I would consider the authorities, wouldn't you?

BTW, collapse is easily debunked: take a two-slit experiment a put a detector at one slit. Interference is destroyed for all photons despite the "fact" that only half the photons "actually" interact with the detector. Collapse cannot account for this. (I put "fact" and "actually" in scare quotes because in true fact all the photons interact with the detector, but not according to the collapse theory.)

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