Your description of the interpretation in your book, "How To Teach Quantum Physics To Your Dog," was the first one I encountered that didn't lead with multiverse language, that instead approached it in the sense of an austere version of quantum mechanics. It was the first time the idea didn't seem hopelessly outlandish. (You also have the best non-technical description of decoherence I've seen!)
Since then, I've also encountered Jeffrey Barrett's SEP article on Everettian QM. He uses a phrase I like: "pure wave mechanics", which seems like a good way to convey the core idea. The worlds may or may not ever be testable, but pure wave mechanics is and has been.
FWIW, the very issues you discuss regarding complex systems are why I think large objects do not have quantum behavior and cannot be in quantum superposition. I think the isolation necessary to see quantum superposition is significant as is mass (I lean towards the Diósi–Penrose notion).
I would be interested in how the MWI solves the Born rule. Consider the case with a single beam-splitter designed with a 1%/99% probability of reflecting/transmitting. Experimentally, we obtain those odds, but under the MWI both possibilities must happen, which prima facie seems 50/50 odds. Why don't we experience that? In a single reality, rare events happen rarely. In the MWI, rare events happen every time. Yet we rarely find ourselves in those branches.
But I think the real dividing line is literally the Heisenberg Cut. If it exists, the MWI has to be false. If it doesn't exist, if the whole universe is a quantum object, then it has to be true. (Which makes me very interested in those macro quantum experiments.)
So I guess I'm an Everett sympathiser, although the math is beyond me (Schrodinger's equationales me slightly nauseous).
But are there experiments that mess with reversing the split? I.e. "merging" the version of the observer that saw outcome A and the one that saw B, back into a single fuzzy version that kinda saw both?
Please - squish on. It’s appreciated.
And thank you for the most lucid description of Everettian QM I’ve read!
An excellent description of Everettian QM!
Your description of the interpretation in your book, "How To Teach Quantum Physics To Your Dog," was the first one I encountered that didn't lead with multiverse language, that instead approached it in the sense of an austere version of quantum mechanics. It was the first time the idea didn't seem hopelessly outlandish. (You also have the best non-technical description of decoherence I've seen!)
Since then, I've also encountered Jeffrey Barrett's SEP article on Everettian QM. He uses a phrase I like: "pure wave mechanics", which seems like a good way to convey the core idea. The worlds may or may not ever be testable, but pure wave mechanics is and has been.
FWIW, the very issues you discuss regarding complex systems are why I think large objects do not have quantum behavior and cannot be in quantum superposition. I think the isolation necessary to see quantum superposition is significant as is mass (I lean towards the Diósi–Penrose notion).
I would be interested in how the MWI solves the Born rule. Consider the case with a single beam-splitter designed with a 1%/99% probability of reflecting/transmitting. Experimentally, we obtain those odds, but under the MWI both possibilities must happen, which prima facie seems 50/50 odds. Why don't we experience that? In a single reality, rare events happen rarely. In the MWI, rare events happen every time. Yet we rarely find ourselves in those branches.
But I think the real dividing line is literally the Heisenberg Cut. If it exists, the MWI has to be false. If it doesn't exist, if the whole universe is a quantum object, then it has to be true. (Which makes me very interested in those macro quantum experiments.)
So I guess I'm an Everett sympathiser, although the math is beyond me (Schrodinger's equationales me slightly nauseous).
But are there experiments that mess with reversing the split? I.e. "merging" the version of the observer that saw outcome A and the one that saw B, back into a single fuzzy version that kinda saw both?
*meant to say that Schrodinger's equation makes me slightly nauseous