All posts by beyondspacetimeblogging

Live Blogging: Bain

Relation to condensed matter approach: CM systems may have analogues to the physics of relative locality.

Both CM versions encode aspect of EFTs in aspects of parameter space topology. Can be related to p-space curvature.

First version: (1) encode low-energy dynamics  in p-space. (2) Stability of low-energy dynamics. (3) Relate topological invariant to p-space curvature.

Second version: (1) encode internal order of condensate in ground state degeneracy (GSD). (2) Demonstrate stability of GSD. (3) Relate GSD to p-space curvature.

Live Blogging: Bain

Moving on to relative locality: (Amelino-Camelia et al. 2011)

Idea: due to curvature of momentum space. Can see this by comparing the phase spaces of special relativity and GR . Momentum space flat. But for theories with relative locality momentum space curved. Suggestion is that this should happen in QG, because perhaps of non-commutative geometry. Also corrections to relativistic particle dynamics.

 

Live Blogging: Bain

Suppose this: EFT and high-energy theory may not need to be related by approximation, but rather emergence. Then perhaps consistent to claim that an AST can emerge in the form of an EFT of a fundamental condensate.

One route: via failure of law-like deducibility (novelty); with ontological distinctness; and ontological dependence. (micro-physicalism from second two)

Live Blogging: Bain

Claim: EFTs in in both versions of CM approach should aspire to be ASTs.

So aspire toward two fixed points: IR for “high energy” condensate. UV fixed point associated with QCD/GR sector.

But may not be consistent to consider an EFT as an AST.

For AST = fundamental theory to all orders. EFT = theory restricted to a gvien energy scale, beyond which new physics arises.

Live Blogging: Bain

Asymptotic safety: QG must scale towards UV fixed point with a finite number of UV-irrelevant coupling. I.e. decreases toward high energy (fixed point).

finite # of UV-irrelevant couplings.

infinite # of UV-relevant couplings.

Live Blogging: Bain

Goal of Condensed Matter approach: 

construct EFT that mimics GR and Standard Model

Version A: spontaneous broken symmetries and universality. E.g. Volovik model.

Version B: characterized instead by “topological order”. E.g. Zhang and Hu: 4-d fractional quantum Hall Fluid (FQH).

Vary in the kinds of order that are relevant.

Live Blogging: Bain

Condensed matter approach to QG:

Mode decomposition of action, integrate out high energy modes, absorb changes into redefined parameters. If successful, find a fixed point for these transformations.

Can stop just at integrating out of high energy modes. This corresponds to EFT.