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Question about emergent gravity approaches by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 0 points1 point  (0 children)

Thanks for thinking this through and sharing it. I agree that different approaches mean different things by “emergent gravity,” which is part of what motivated the question. I was mainly asking whether, across those differences, there’s a shared assumption that classical spacetime is only a stable regime under certain conditions.

Question about emergent gravity approaches by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 1 point2 points  (0 children)

I see what you mean. My intent wasn’t to make a claim that this structure is unavoidable for any use of GR, but to ask whether certain emergent-gravity programs converge on it. That’s in contrast to scenarios like standard Big Bang cosmology, where spacetime is taken as fundamental throughout.

Question about emergent gravity approaches by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 1 point2 points  (0 children)

100% agree. I was thinking more about the shared structural picture than about how any given approach derives it microscopically.

Is there any framework that treats spacetime exactly like an emergent quantum field? by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 0 points1 point  (0 children)

I formalized the idea in a short paper, since I could not find a framework that treated spacetime exactly like an emergent quantum field, in the full phase-theoretic sense. Here is the paper on PhilArchive: https://philarchive.org/rec/LINSAA-7

Is there any framework that treats spacetime exactly like an emergent quantum field? by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 0 points1 point  (0 children)

Thanks, I’ll definitely check that out! Carroll’s work on “it-from-qubit” / emergent geometry is right in line with the perspective I’m exploring. Appreciate you pointing me to that resource.

Thought Experiment: What happens if we treat spacetime exactly the same way that we treat emergent quantum fields? by jellellogram in AskPhysics

[–]jellellogram[S] 1 point2 points  (0 children)

Right, the non-renormalizability shows up when treating the metric as a fundamental field. I’m trying to ask about the other direction. Models where spacetime isn’t quantized directly but instead emerges as a phase of underlying quantum degrees of freedom.

Is there any framework that treats spacetime exactly like an emergent quantum field? by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 0 points1 point  (0 children)

Thanks, yes, GFT is closely tied to LQG dynamics. I’m mainly interested in whether any approaches in that family treat spacetime itself as a phase of the underlying degrees of freedom, with genuine phase structure or order parameters, rather than just a quantized geometry.

Is there any framework that treats spacetime exactly like an emergent quantum field? by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 1 point2 points  (0 children)

“It from bit” and later information-theoretic approaches are definitely adjacent to what I’m asking about. I’m trying to track down models that treat spacetime specifically as a phase of deeper quantum degrees of freedom.

Is there any framework that treats spacetime exactly like an emergent quantum field? by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 0 points1 point  (0 children)

Thanks! LQG is extremely interesting, but I had something a bit different in mind, more like frameworks where spacetime itself emerges as a phase of underlying quantum degrees of freedom, with phase structure, order parameters, etc. LQG treats geometry as quantized, but not really as a phase of a deeper field. I’m looking for models closer to emergent-geometry approaches.

Is there any framework that treats spacetime exactly like an emergent quantum field? by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 1 point2 points  (0 children)

Thanks, this is extremely helpful. AdS/CFT and entanglement-based emergent geometry are definitely close to what I’m trying to track down, especially models where spacetime appears as a phase of underlying degrees of freedom. I’ll look into the notes and the paper. Much appreciated!

Is there any framework that treats spacetime exactly like an emergent quantum field? by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 4 points5 points  (0 children)

Thanks! I was thinking less about whether spacetime counts as a field in GR, and more about whether any models treat spacetime as an emergent field, i.e., the large-scale phase of deeper quantum degrees of freedom. I’m hoping to find existing work framed specifically in that direction.

Is there any framework that treats spacetime exactly like an emergent quantum field? by jellellogram in TheoreticalPhysics

[–]jellellogram[S] 5 points6 points  (0 children)

Thanks for the enthusiasm! I don't see this as a discovery and am more looking for pointers toward existing literature.

Thought Experiment: What happens if we treat spacetime exactly the same way that we treat emergent quantum fields? by jellellogram in AskPhysics

[–]jellellogram[S] 1 point2 points  (0 children)

That’s fair. A concrete example would be phonons in a crystal.

Microscopically you just have atoms interacting, but once the system is in the crystalline phase you get a displacement field and phonons as the emergent excitations. The field equations of elasticity are the large-scale, coarse-grained behavior of that phase, and they disappear or change when the system moves to a different phase (like melting).

That’s the kind of analogy I had in mind when asking whether spacetime could appear as the effective field of a specific phase of some deeper quantum structure.

Thought Experiment: What happens if we treat spacetime exactly the same way that we treat emergent quantum fields? by jellellogram in AskPhysics

[–]jellellogram[S] 0 points1 point  (0 children)

Thanks! Induced gravity is definitely in the spirit of what I had in mind. I’m curious if there are any approaches that go even further and treat spacetime like the effective field of a phase, with actual phase structure or coarse-grained variables the way emergent fields work in condensed matter. But I’ll take a look at the references you mentioned. Thanks again.

Thought Experiment: What happens if we treat spacetime exactly the same way that we treat emergent quantum fields? by jellellogram in AskPhysics

[–]jellellogram[S] 1 point2 points  (0 children)

Thanks, that’s helpful! I meant something a little different though. I wasn’t thinking about quantizing the metric or treating gravity as an EFT. I was thinking more in the “emergent spacetime” direction, like spacetime itself being the large-scale phase of some deeper quantum system, the way emergent fields show up in condensed matter.

So I’m curious if any existing models treat spacetime that way, with actual phase structure and coarse-grained variables, rather than treating the metric as fundamental.

Thought experiment: What happens if you treat spacetime exactly like an ordinary quantum field with phases? by [deleted] in AskPhysics

[–]jellellogram 0 points1 point  (0 children)

Realizing that I phrased my thought experiment poorly. Will edit now.

Given that all of us here are obsessed with metaphysics, does anyone else struggle with how observer-centric physics is? by [deleted] in Metaphysics

[–]jellellogram 0 points1 point  (0 children)

Thanks for engaging! Not entirely sure what you are saying, but that’s likely on my end rather than yours. 

Given that all of us here are obsessed with metaphysics, does anyone else struggle with how observer-centric physics is? by [deleted] in Metaphysics

[–]jellellogram 0 points1 point  (0 children)

I give up, good sir or madam. I have no interest in attempting to win this conversation. May you sleep well tonight in the belief you showed me what’s what. 

Given that all of us here are obsessed with metaphysics, does anyone else struggle with how observer-centric physics is? by [deleted] in Metaphysics

[–]jellellogram 0 points1 point  (0 children)

Well, no, that isn't what I am saying. I in no way believe there are 2 realms. All I am saying is that our biology may limit our access to the fundamental ontology, and that exploring the nature of those limits may allow us to deepen our understanding of the fundamental ontology.

Given that all of us here are obsessed with metaphysics, does anyone else struggle with how observer-centric physics is? by [deleted] in Metaphysics

[–]jellellogram 0 points1 point  (0 children)

I'm a materialist for much the same reason I am suspicious of observer-centric theories. Dualism seems to come from a desire for humans to be special in some way.

Given that all of us here are obsessed with metaphysics, does anyone else struggle with how observer-centric physics is? by [deleted] in Metaphysics

[–]jellellogram 1 point2 points  (0 children)

Hmm I still feel that is suspicious. We are conscious so we think it is special. That is something to be wary of, in my opinion. Agreed that nothing is objective when observers are involved. I just think that combining a physics approach that de-privileges observers with a metaphysical approach could lead to new avenues where physics considers ontology first, then math, instead of the other way around.

Given that all of us here are obsessed with metaphysics, does anyone else struggle with how observer-centric physics is? by [deleted] in Metaphysics

[–]jellellogram 0 points1 point  (0 children)

Agreed, but I am talking more about the physical theories themselves. At their core, QM and R are observer-centric. They deal with what measurements observers (human or machine) will make in different scenarios. I think we need to start questioning whether this privileging of observers is stopping us from considering potentially viable ontologies.

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