# The Universe as a Quantum Encoder

@inproceedings{Cotler2022TheUA, title={The Universe as a Quantum Encoder}, author={Jordan S. Cotler and Andrew Strominger}, year={2022} }

Quantum mechanical unitarity in our universe is challenged both by the notion of the big bang, in which nothing transforms into something, and the expansion of space, in which something transforms into more something. This motivates the hypothesis that quantum mechanical time evolution is always isometric, in the sense of preserving inner products, but not necessarily unitary. As evidence for this hypothesis we show that in two spacetime dimensions (i) there is net entanglement entropy produced…

## 4 Citations

### Emergent metric space-time from matrix theory

- PhysicsJournal of High Energy Physics
- 2022

Abstract
The IKKT matrix model yields an emergent space-time. We further develop these ideas and give a proposal for an emergent metric. Based on previous numerical studies of this model, we provide…

### Unitarity problems for an effective field theory description of early universe cosmology

- PhysicsThe European Physical Journal C
- 2022

In the context of Effective Field Theory, the Hilbert space of states increases in an expanding universe. Hence, the time evolution cannot be unitary. The formation of structure is usually studied…

### Hyperbolic Lattice for Scalar Field Theory in AdS$_3$

- Physics
- 2022

: We construct a tessellation of AdS 3 , by extending the equilateral triangulation of AdS 2 on the Poincar´e disk based on the (2 , 3 , 7) triangle group, suitable for studying strongly coupled…

### Holographic local operator quenches in BCFTs

- PhysicsJournal of High Energy Physics
- 2022

Abstract
We present a gravity dual of local operator quench in a two-dimensional CFT with conformal boundaries. This is given by a massive excitation in a three-dimensional AdS space with the end of…

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