Scott Aaronson's cautious optimism for the MWI

calef

http://www.scottaaronson.com/blog/?p=1103

Eliezer's gung-ho attitude about the realism of the Many Worlds Interpretation always rubbed me the wrong way, especially in the podcast between both him and Scott (around 8:43 in http://bloggingheads.tv/videos/2220). I've seen a similar sentiment expressed before about the MWI sequences. And I say that still believing it to be the most seemingly correct of the available interpretations.

I feel Scott's post does an excellent job grounding it as a possibly correct, and in-principle falsifiable interpretation.

http://www.scottaaronson.com/blog/?p=1103

I feel Scott's post does an excellent job grounding it as a possibly correct, and in-principle falsifiable interpretation.

As far as I can tell (being a non-physicist), the Transactional Interpretation shares the mathematical simplicity of MWI. And here Kastner and Cramer argue that TI can derive the Born probabilities naturally, whereas MWI is said to need a detour through "the application of social philosophy and decision theory to subjectively defined ‘rational’ observers". So maybe TI is simpler.

The "possibilities" they posit seem quite parallel (pardon the pun) to the multiple worlds or bifurcated observers of MWI, so I don't see the philosophical advantage there, that they tout. But integrating the Born probabilities more tightly into the physics is a plus, if true.

Stopped reading the linked paper when it made a mistake because of treating "worlds" as literal things being "split off." Gotta use quantum mechanics if you're going to talk about quantum mechanics. Maybe they corrected it later, but I didn't even want to wade through to find out.

5Mitchell_Porter14y

With respect to Born probabilities, TI is on the level of MWI, it has no derivation for them. Similarly, its ontology is rhetorical rather than rigorous. A central issue for any zigzag-in-time or retrocausal theory of QM would be vacuum polarization, which was the stumbling block for the most serious effort, by Feynman and Wheeler. But Feynman-Wheeler theory is also where the path integral was born, so TI advocates could say, we just need to go back and finish it properly.