# Simulating the universe(s): from cosmic bubble collisions to cosmological observables with numerical relativity

@article{Wainwright2014SimulatingTU, title={Simulating the universe(s): from cosmic bubble collisions to cosmological observables with numerical relativity}, author={Carroll L. Wainwright and Matthew Camp Johnson and Hiranya V. Peiris and Anthony Aguirre and Luis Lehner and Steven L. Liebling}, journal={Journal of Cosmology and Astroparticle Physics}, year={2014}, volume={2014}, pages={030-030} }

The theory of eternal inflation in an inflaton potential with multiple vacua predicts that our universe is one of many bubble universes nucleating and growing inside an ever-expanding false vacuum. The collision of our bubble with another could provide an important observational signature to test this scenario. We develop and implement an algorithm for accurately computing the cosmological observables arising from bubble collisions directly from the Lagrangian of a single scalar field. We first…

## Figures and Tables from this paper

## 35 Citations

Simulating the universe(s) II: phenomenology of cosmic bubble collisions in full General Relativity

- Physics
- 2014

Observing the relics of collisions between bubble universes would provide direct evidence for the existence of an eternally inflating Multiverse; the non-observation of such events can also provide…

Simulating the Universe(s) III: Observables for the full bubble collision spacetime

- Physics
- 2015

This is the third paper in a series establishing a quantitative relation between inflationary scalar field potential landscapes and the relic perturbations left by the collision between bubbles…

Cosmic Bubble Collisions Observable Signature of A Classical Transition

- 2015

The theory of inflation was introduced to resolve many existing observational problems in cosmology. Inflation becomes eternal when a region of space continuously spawns noninflation regions. This…

Observable Signatures of a Classical Transition

- Physics
- 2015

Eternal inflation arising from a potential landscape predicts that our universe is one realization of many possible cosmological histories. One way to access different cosmological histories is via…

Cosmic bubble and domain wall instabilities III: The role of oscillons in three-dimensional bubble collisions

- Physics
- 2015

We study collisions between pairs of bubbles nucleated in an ambient false vacuum. For the first time, we include the effects of small initial (quantum) fluctuations around the instanton profiles…

Numerical Relativity and Astrophysics

- Physics
- 2014

Throughout the Universe many powerful events are driven by strong gravitational effects that require general relativity to fully describe them. These include compact binary mergers, black hole…

A numerical relativity scheme for cosmological simulations

- Physics
- 2016

Cosmological simulations involving the fully covariant gravitational dynamics may prove relevant in understanding relativistic/non-linear features and, therefore, in taking better advantage of the…

Cosmological nonlinear structure formation in full general relativity

- Physics
- 2014

We perform numerical evolutions of cosmological scenarios using a standard general relativistic code in spherical symmetry. We concentrate on two different situations: initial matter distributions…

Cosmic bubble and domain wall instabilities I: parametric amplification of linear fluctuations

- Physics
- 2014

This is the first paper in a series where we study collisions of nucleated bubbles taking into account the effects of small initial (quantum) fluctuations in a fully 3+1-dimensional setting. In this…

Black hole formation from the collision of plane-fronted gravitational waves

- PhysicsPhysical Review D
- 2018

This paper introduces a new effort to study the collision of plane-fronted gravitational waves in four dimensional, asymptotically flat spacetime, using numerical solutions of the Einstein equations.…

## References

SHOWING 1-10 OF 201 REFERENCES

Determining the outcome of cosmic bubble collisions in full General Relativity

- Physics
- 2012

Cosmic bubble collisions provide an important possible observational window on the dynamics of eternal inflation. In eternal inflation, our observable universe is contained in one of many bubbles…

When do colliding bubbles produce an expanding universe

- Physics
- 2004

It is intriguing to consider the possibility that the big bang of the standard (3+1)-dimensional cosmology originated from the collision of two branes within a higher dimensional spacetime, leading…

GRAVITATIONAL EFFECTS IN BUBBLE COLLISIONS

- Physics
- 1983

We investigate the effects of gravitation in the collision of two bubbles in the very early universe, using the thin-wall approximation. In general, the collision of two bubbles gives rise to modulus…

Towards observable signatures of other bubble universes. II. Exact solutions for thin-wall bubble collisions

- Physics
- 2008

We assess the effects of a collision between two vacuum bubbles in the thin-wall limit. After describing the outcome of a generic collision possessing the expected hyperbolic symmetry, we focus on…

Multiple cosmic collisions and the microwave background power spectrum

- Physics
- 2013

Collisions between cosmic bubbles of different vacua are a generic feature of false vacuum eternal inflation scenarios. While previous studies have focused on the consequences of a single collision…

Watching worlds collide: effects on the CMB from cosmological bubble collisions

- Physics
- 2008

We extend our previous work on the cosmology of Coleman-de Luccia bubble collisions. Within a set of approximations we calculate the effects on the cosmic microwave background (CMB) as seen from…

When Worlds Collide

- Physics
- 2007

We analyze the cosmological signatures visible to an observer in a Coleman-de Luccia bubble when another such bubble collides with it. We use a gluing procedure to generalize the results of…

Analyzing Cosmic Bubble Collisions

- Physics
- 2012

We develop a set of controlled, analytic approximations to study the effects of bubble collisions on cosmology. We expand the initial perturbation to the inflaton field caused by the collision in a…

Eternal inflation, bubble collisions, and the disintegration of the persistence of memory

- Physics
- 2009

We compute the probability distribution for bubble collisions in an inflating false vacuum which decays by bubble nucleation. Our analysis generalizes previous work of Guth, Garriga, and Vilenkin to…

Observing the Multiverse with Cosmic Wakes

- Physics
- 2013

Current theories of the origin of the Universe, including string theory, predict the existence of a multiverse containing many bubble universes. These bubble universes will generically collide, and…