Noncommutative spacetime, stringy spacetime uncertainty principle, and density fluctuations
By Robert Brandenberger, Pei-Ming Ho. 2002
169 citations recorded by the source corpus.
We propose a variation of spacetime noncommutative field theory to realize the stringy spacetime uncertainty relation without breaking any of the global symmetries of the homogeneous isotropic universe. We study the spectrum of metric perturbations in this model for a wide class of accelerating background cosmologies. Spacetime noncommutativity leads to a coupling between the fluctuation modes and the background cosmology which is nonlocal in time. For each mode, there is a critical time at which the spacetime uncertainty relation is saturated. This is the time when the mode is generated. These effects lead to a spectrum of fluctuations whose spectral index is different from what is obtained for commutative spacetime in the infrared region, but is unchanged in the ultraviolet region. In the special case of an exponentially expanding background, we find a scale-invariant spectrum. but with a different magnitude than in the context of commutative spacetime if the Hubble constant is above the string scale.
Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics, Statistical and Nonlinear Physics
View Paper: https://www.semanticscholar.org/paper/045cf03b869e8f34a00ac456fabe4cbd18155350
How researchers see this paper
The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.
In Astronomy and Astrophysics
- Robert Brandenberger
- Jérôme Martin
- U. Danielsson
- Sabine Hossenfelder
- P. Peter
- Yi-Fu Cai
- Yi Wang
- C. Burgess
In Nuclear and High Energy Physics
- Jérôme Martin
- Robert Brandenberger
- U. Danielsson
- Sabine Hossenfelder
- P. Peter
- Yi-Fu Cai
- Emmanuel N. Saridakis
- Max Tegmark
In Statistical and Nonlinear Physics
- U. Danielsson
- Robert Brandenberger
- Jérôme Martin
- Sabine Hossenfelder
- Giovanni Amelino-Camelia
- P. Peter
- Yi-Fu Cai
- Abdel Nasser Tawfik
Citations in the corpus
- Inflation, holography, and the choice of vacuum in de Sitter space (2002, background): “In several recent works the rationality of this assumption has been questioned, [2-26].”
- Trans-Planckian issues for inflationary cosmology (2012, background): “Some authors have considered general modifications of physics on Planck scales such as modified uncertainty principles [43], space-space non-commutativty [27, 44] and space-time non-commutativity [45] and computed the changes in the spectrum of perturbations in an inflationary cosmology.”
- Minimal Length Scale Scenarios for Quantum Gravity (2012, background): “perturbations have been studied in [68].”