text: 418,85,1372576318374563842,21611239,Sean Carroll,"All of reality can be modeled as just a vector looping around in a really-big Hilbert space. New semi-technical paper from me: <LINK> Roughly speaking this is the perspective advocated by @ashmeetastro and me in our Mad-Dog Everettianism paper. The new one is more aimed at philosophers. <LINK> And yes, this is the paper that I wrote first, before putting any references in. Hopefully I didn't forget anyone. But I'm confident they will remind me if I did. The paper leans into the idea that the fundamental nature of reality could be *radically* different from our familiar world of objects moving around in space and interacting with each other. All that stuff is a higher-level emergent approximation. It's perfectly okay to be skeptical precisely because of that radical divergence between theory and experience. But it's also worth considering. Who says the fundamental nature of reality should be anything at all like our everyday experience? @LizardOrman Actually only quantum systems can be represented that way, not classical ones. The question is whether the vector is fundamental, or is built on top of some ontology such as particles/fields propagating in space. @henry_maxfield I presume there are any number of equivalent ways to represent the structure of a quantum theory; in the Schrödinger picture it's the Hamiltonian. You use a time parameter in the construction, but it's not necessarily ""preferred,"" as I discuss in the paper. @watsona4 Thanks! @henry_maxfield Yes, that would be how boosts work in the standard Hamiltonian formulation of QFT. But here it might only be an approximate symmetry. @henry_maxfield I think a physical realization should be thought of as an equivalence class of solutions, each corresponding to a choice of time variable. @henry_maxfield This might not be a Twitterable conversation. Maybe in person someday.",https://arxiv.org/abs/2103.09780,"I defend the extremist position that the fundamental ontology of the world consists of a vector in Hilbert space evolving according to the Schr\""odinger equation. The laws of physics are determined solely by the energy eigenspectrum of the Hamiltonian. The structure of our observed world, including space and fields living within it, should arise as a higher-level emergent description. I sketch how this might come about, although much work remains to be done. ",Reality as a Vector in Hilbert Space,11,"['All of reality can be modeled as just a vector looping around in a really-big Hilbert space. New semi-technical paper from me:\n<LINK>', 'Roughly speaking this is the perspective advocated by @ashmeetastro and me in our Mad-Dog Everettianism paper. The new one is more aimed at philosophers.\nhttps://t.co/R3SolxesK1', ""And yes, this is the paper that I wrote first, before putting any references in. Hopefully I didn't forget anyone. But I'm confident they will remind me if I did."", 'The paper leans into the idea that the fundamental nature of reality could be *radically* different from our familiar world of objects moving around in space and interacting with each other. All that stuff is a higher-level emergent approximation.', ""It's perfectly okay to be skeptical precisely because of that radical divergence between theory and experience. But it's also worth considering. Who says the fundamental nature of reality should be anything at all like our everyday experience?"", '@LizardOrman Actually only quantum systems can be represented that way, not classical ones. The question is whether the vector is fundamental, or is built on top of some ontology such as particles/fields propagating in space.', '@henry_maxfield I presume there are any number of equivalent ways to represent the structure of a quantum theory; in the Schrödinger picture it\'s the Hamiltonian. You use a time parameter in the construction, but it\'s not necessarily ""preferred,"" as I discuss in the paper.', '@watsona4 Thanks!', '@henry_maxfield Yes, that would be how boosts work in the standard Hamiltonian formulation of QFT. But here it might only be an approximate symmetry.', '@henry_maxfield I think a physical realization should be thought of as an equivalence class of solutions, each corresponding to a choice of time variable.', '@henry_maxfield This might not be a Twitterable conversation. Maybe in person someday.']",21,03,1859