# Physical theories, eternal inflation, and the quantum universe

@article{Nomura2011PhysicalTE, title={Physical theories, eternal inflation, and the quantum universe}, author={Yasunori Nomura}, journal={Journal of High Energy Physics}, year={2011}, volume={2011}, pages={1-68} }

A bstractInfinities in eternal inflation have long been plaguing cosmology, making any predictions highly sensitive to how they are regulated. The problem exists already at the level of semi-classical general relativity, and has a priori nothing to do with quantum gravity. On the other hand, we know that certain problems in semi-classical gravity, for example physics of black holes and their evaporation, have led to understanding of surprising, quantum natures of spacetime and gravity, such as…

## 78 Citations

Relativeness in quantum gravity: limitations and frame dependence of semiclassical descriptions

- Physics
- 2014

A bstractConsistency between quantum mechanical and general relativistic views of the world is a longstanding problem, which becomes particularly prominent in black hole physics. We develop a…

Quantum Mechanics, Spacetime Locality, and Gravity

- Physics
- 2011

Quantum mechanics introduces the concept of probability at the fundamental level, yielding the measurement problem. On the other hand, recent progress in cosmology has led to the “multiverse”…

Quantum Mechanics, Gravity, and the Multiverse

- Physics
- 2012

Abstract The discovery of accelerating expansion of the universe has led us to take the dramatic view that our universe may be one of the many universes in which low energy physical laws take…

Black holes, entropies, and semiclassical spacetime in quantum gravity

- Physics
- 2014

A bstractWe present a coherent picture of the quantum mechanics of black holes. The picture does not require the introduction of any drastically new physical effect beyond what is already known; it…

Constraints on Cosmology and Quantum Gravity from Quantum Mechanics and Quantum Field Theory

- Physics
- 2017

Typical cosmological states have structure, obey to very good approximation the laws of classical physics on large scales, and are far from equilibrium. Typical quantum-mechanical states have none of…

The Cosmological Constant in the Quantum Multiverse

- Physics
- 2011

Recently, a new framework for describing the multiverse has been proposed which is based on the principles of quantum mechanics. The framework allows for well-defined predictions, both regarding…

Toward a Holographic Theory for General Spacetimes

- Physics
- 2017

Author(s): Nomura, Y; Salzetta, N; Sanches, F; Weinberg, SJ | Abstract: © 2017 American Physical Society. We study a holographic theory of general spacetimes that does not rely on the existence of…

Eternal inflation and the quantum birth of cosmic structure

- Economics
- 2017

We consider the eternal inflation scenario of the slow-roll/chaotic type with the additional element of an objective collapse of the wave function. The incorporation of this new agent to the…

Extended Rindler spacetime and a new multiverse structure

- Physics
- 2017

This is the first of a series of papers in which we use analyticity properties of quantum fields propagating on a spacetime to uncover a new multiverse geometry when the classical geometry has…

Classical spacetimes as amplified information in holographic quantum theories

- PhysicsPhysical Review D
- 2018

Author(s): Nomura, Y; Rath, P; Salzetta, N | Abstract: © 2018 authors. Published by the American Physical Society. We argue that classical spacetimes represent amplified information in the…

## References

SHOWING 1-10 OF 122 REFERENCES

Predictions in eternal inflation

- Physics
- 2008

In generic models of cosmological inflation, quantum fluctuations strongly influence the spacetime metric and produce infinitely many regions where the end of inflation (reheating) is delayed until…

Holographic framework for eternal inflation

- Physics
- 2006

In this paper we provide some circumstantial evidence for a holographic duality between bubble nucleation in an eternally inflating universe and a Euclidean conformal field theory (CFT). The…

Eternal inflation: the inside story

- Physics
- 2006

Motivated by the lessons of black hole complementarity, we develop a causal patch description of eternal inflation. We argue that an observer cannot ascribe a semiclassical geometry to regions…

Born in an Infinite Universe: A Cosmological Interpretation of Quantum Mechanics

- Physics
- 2011

We study the quantum measurement problem in the context of an infinite, statistically uniform space, as could be generated by eternal inflation. It has recently been argued that when identical copies…

The world as a hologram

- Physics
- 1994

According to ’t Hooft the combination of quantum mechanics and gravity requires the three‐dimensional world to be an image of data that can be stored on a two‐dimensional projection much like a…

Dimensional Reduction in Quantum Gravity

- Physics
- 1993

The requirement that physical phenomena associated with gravitational collapse should be duly reconciled with the postulates of quantum mechanics implies that at a Planckian scale our world is not…

Breakdown of Predictability in Gravitational Collapse

- Physics
- 1976

The principle of equivalence, which says that gravity couples to the energy-momentum tensor of matter, and the quantum-mechanical requirement that energy should be positive imply that gravity is…

Census Taking in the Hat: FRW/CFT Duality

- Physics
- 2009

In this paper a holographic description of eternal inflation is developed. We focus on the description of an open Friedmann-Robertson-Walker (FRW) universe that results from a tunneling event in…

The stretched horizon and black hole complementarity.

- PhysicsPhysical review. D, Particles and fields
- 1993

Three postulates asserting the validity of conventional quantum theory, semiclassical general relativity, and the statistical basis for thermodynamics are introduced as a foundation for the study of…