Holography and the scale invariance of density fluctuations
@article{Magueijo2006HolographyAT, title={Holography and the scale invariance of density fluctuations}, author={Jo{\~a}o Magueijo and Lee Smolin and Carlo R. Contaldi}, journal={Classical and Quantum Gravity}, year={2006}, volume={24}, pages={3691 - 3699} }
We study a scenario for the very early universe in which there is a fast phase transition from a non-geometric, high temperature phase to a low temperature, geometric phase described by a classical solution to the Einstein equations. In spite of the absence of a classical metric, the thermodynamics of the high temperature phase may be described by making use of the holographic principle. The thermal spectrum of fluctuations in the high temperature phase manifests itself after the phase…
40 Citations
Quantum gravity at Hubble scales determines the cosmological constant and the amplitude of primordial perturbations
- Physics
- 2017
Gravity controls the amount of information that is accessible to any specific observer. We quantify the notion of cosmic information (‘CosmIn’) for the case of an eternal observer in the universe.…
Early Universe Cosmology in Internal Relativity
- Physics
- 2008
We present a new approach to early universe cosmology. Inflation is replaced by a phase transition in which both matter and geometry are created simultaneously. We calculate the spectrum of metric…
Cosmic information, the cosmological constant and the amplitude of primordial perturbations
- Physics
- 2017
Inhomogeneous universe from group field theory condensate
- PhysicsJournal of Cosmology and Astroparticle Physics
- 2019
One of the fundamental challenges for quantum cosmology is to explain the emergence of our macroscopic Universe from physics at the Planck scale. In the group field theory (GFT) approach to quantum…
Quantum Graphity
- Physics
- 2006
We introduce a new model of background independent physics in which the degrees of freedom live on a complete graph and the physics is invariant under the permutations of all the points. We argue…
Big Bang as a Critical Point
- 2017
This article addresses the issue of possible gravitational phase transitions in the early universe. We suggest that a second-order phase transition observed in the Causal Dynamical Triangulations…
Towards a Cosmological GFT Condensate Scenario : Gauge-Invariant Perturbations 16 IV
- Physics
- 2019
One of the fundamental challenges for quantum cosmology is to explain the emergence of our macroscopic Universe from physics at the Planck scale. In the group field theory (GFT) approach to quantum…
Disordered locality as an explanation for the dark energy
- Physics
- 2009
We discuss a novel explanation of the dark energy as a manifestation of macroscopic nonlocality coming from quantum gravity, as proposed by Markopoulou [F. Markopoulou (private communication)]. It…
References
SHOWING 1-10 OF 43 REFERENCES
SUPERLUMINARY UNIVERSE: A POSSIBLE SOLUTION TO THE INITIAL VALUE PROBLEM IN COSMOLOGY
- Physics
- 1993
The spontaneous breaking of local Lorentz invariance in the early Universe, associated with a first order phase transition at a critical time tc, generates a large increase in the speed of light and…
Could thermal fluctuations seed cosmic structure
- Physics
- 2003
We examine the possibility that thermal, rather than quantum, fluctuations are responsible for seeding the structure of our universe. We find that while the thermalization condition leads to nearly…
Producing a scale-invariant spectrum of perturbations in a Hagedorn phase of string cosmology.
- PhysicsPhysical review letters
- 2006
In this cosmological scenario, the early Hagedorn phase of string gas cosmology goes over smoothly into the radiation-dominated phase of standard cosmology, without having a period ofcosmological inflation.
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…
A Time varying speed of light as a solution to cosmological puzzles
- Physics
- 1999
We consider the cosmological implications of light travelling faster in the early Universe. We propose a prescription for deriving corrections to the cosmological evolution equations while the speed…
Origin of the large scale structures of the universe
- Physics
- 2004
We revise the statistical properties of the primordial cosmological density anisotropies that, at the time of matter-radiation equality, seeded the gravitational development of large scale structures…
More on the spectrum of perturbations in string gas cosmology
- Physics
- 2006
String gas cosmology is rewritten in the Einstein frame. In an effective theory in which a gas of closed strings is coupled to a dilaton gravity background without any potential for the dilaton, the…
New varying speed of light theories
- Physics
- 2003
We review recent work on the possibility of a varying speed of light (VSL). We start by discussing the physical meaning of a varying-c, dispelling the myth that the constancy of c is a matter of…
Black hole evaporation without information loss
- Physics
- 1994
An approach to black hole quantization is proposed wherein it is assumed that quantum coherence is preserved. After giving our motivations for such a quantization procedure we formulate the…