I’m into the final third of Smolin’s “Einstein’s Unfinished Revolution” – his summary of lessons learned from his thesis.
As Sabine Hossenfelder’s review points out, scientifically, the tone is speculative, suggesting more work and experimentation needed to complete the job. That’s true, he’s not making wild claims.
“He deserves applause for also mentioning the Montevideo interpretation and superdeterminism, though clearly he doesn’t like either. I have found his evaluation of these approaches overall balanced and fair.”
There are really two strands to Smolin here:
One is the “plea” for realism in science in the face of so much mathematical abstraction – in say Copenhagen quantum mechanics – that works but doesn’t even attempt to explain what might be real. (He calls it a monumental scandal that the unreality of this choice simply became the accepted orthodoxy – for many decades of science teaching and practice.)
The second thread throughout is positing Bohmian pilot-wave mechanics, Einstein, deBroglie, Wheeler, Bell (ie Paris) as an alternative to the Bohr / Heisenberg (ie Copenhagen) fan club. An alternative that is more “realist” in the sense that both wave and particle manifestations are “beable” rather than any uncertainty about one or the other. (Smolin – and Hossenfelder in her review and comments – dwell at length on the and/or both/either interpretations of superposition and wave-particle duality, location / momentum uncertainty.)
But he points out that both theories come with the baggage of infinite decision-forks of every possible evolutionary history somehow being “real”, not just the actual path(s) taken. If the Everett “many worlds” take on Copenhagen is just a fudge that permits anything and everything conceivable and therefore explains nothing real, then the Paris take on forking paths of pilot-waves might seem very similar.
“A perceptive reader might be troubled by this similarity”
Yes, I was well ahead of him before we got to this sentence. And also in the metaphysics of our demands for “reality”. Smolin clearly yearns for primary reality to be particulate matter with the wave functions simply as guides (pilot waves).
“This brings up a hidden, perhaps unconscious assumption made by adherents of pilot-wave theory [ie himself here] which is that the reality that we observers perceive and measure is composed of matter constructed from the particles [in this theory].”
“To make sense of pilot-wave theory we must privilege the particles and postulate that the world we perceive consists of the particles.”
Smolin has already dismissed epistemic models based on what we can “know” in favour of ontologies of what really exists “out there”. But this is where I still believe he is missing a trick.
The knowledge model is still about “knowables” in the same way as his “beables” – there is no subjective observer involved in making them real, there is no measurement problem, no distinction between detector ensembles and otherwise real ensembles. “Detection” is simply the relations of significant points of “knowable” information being new interactions / arrangements / patterns of information – whether the participating object is a detector / observer or not. They’re “interactables” maybe?
Information is itself the fundamental reality behind BOTH particles and waves (in my book).
[He makes much positive reference to erstwhile colleague Carlo Rovelli, though ultimately disagreeing with his conclusions – which, as I’ve reported before, seem much closer to mine. Like Rovelli he uses “atom” in the intended Democritan sense, not the unfortunate consequence of the last century of unreal physics. All good.]
Smolin is railing at the right problem and he’s so close to the right solution, but maybe missing a trick. Reading on …