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Title: Effects on the CMB from compactification before inflation

Abstract

Many theories beyond the Standard Model include extra dimensions, though these have yet to be directly observed. In this work we consider the possibility of a compactification mechanism which both allows extra dimensions and is compatible with current observations. This compactification is predicted to leave a signature on the CMB by altering the amplitude of the low l multipoles, dependent on the amount of inflation. Recently discovered CMB anomalies at low multipoles may be evidence for this. In our model we assume the spacetime is the product of a four-dimensional spacetime and flat extra dimensions. Before the compactification, both the four-dimensional spacetime and the extra dimensions can either be expanding or contracting independently. Taking into account physical constraints, we explore the observational consequences and the plausibility of these different models.

Authors:
 [1];  [2]; ;  [3]
  1. Physics Program, Bard College, 30 Campus Rd, Annandale-on-Hudson, NY 12504 (United States)
  2. IKERBASQUE, Basque Foundation for Science, 48011, Bilbao (Spain)
  3. Institute of Cosmology, Department of Physics and Astronomy, Tufts University, Medford, MA 02155 (United States)
Publication Date:
OSTI Identifier:
22679903
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Cosmology and Astroparticle Physics; Journal Volume: 2017; Journal Issue: 04; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMPLITUDES; COMPACTIFICATION; COSMOLOGICAL INFLATION; FOUR-DIMENSIONAL CALCULATIONS; MULTIPOLES; RELICT RADIATION; SPACE-TIME; STANDARD MODEL

Citation Formats

Kontou, Eleni-Alexandra, Blanco-Pillado, Jose J., Hertzberg, Mark P., and Masoumi, Ali, E-mail: elenikontou@cosmos.phy.tufts.edu, E-mail: josejuan.blanco@ehu.es, E-mail: mark.hertzberg@tufts.edu, E-mail: ali@cosmos.phy.tufts.edu. Effects on the CMB from compactification before inflation. United States: N. p., 2017. Web. doi:10.1088/1475-7516/2017/04/034.
Kontou, Eleni-Alexandra, Blanco-Pillado, Jose J., Hertzberg, Mark P., & Masoumi, Ali, E-mail: elenikontou@cosmos.phy.tufts.edu, E-mail: josejuan.blanco@ehu.es, E-mail: mark.hertzberg@tufts.edu, E-mail: ali@cosmos.phy.tufts.edu. Effects on the CMB from compactification before inflation. United States. doi:10.1088/1475-7516/2017/04/034.
Kontou, Eleni-Alexandra, Blanco-Pillado, Jose J., Hertzberg, Mark P., and Masoumi, Ali, E-mail: elenikontou@cosmos.phy.tufts.edu, E-mail: josejuan.blanco@ehu.es, E-mail: mark.hertzberg@tufts.edu, E-mail: ali@cosmos.phy.tufts.edu. Sat . "Effects on the CMB from compactification before inflation". United States. doi:10.1088/1475-7516/2017/04/034.
@article{osti_22679903,
title = {Effects on the CMB from compactification before inflation},
author = {Kontou, Eleni-Alexandra and Blanco-Pillado, Jose J. and Hertzberg, Mark P. and Masoumi, Ali, E-mail: elenikontou@cosmos.phy.tufts.edu, E-mail: josejuan.blanco@ehu.es, E-mail: mark.hertzberg@tufts.edu, E-mail: ali@cosmos.phy.tufts.edu},
abstractNote = {Many theories beyond the Standard Model include extra dimensions, though these have yet to be directly observed. In this work we consider the possibility of a compactification mechanism which both allows extra dimensions and is compatible with current observations. This compactification is predicted to leave a signature on the CMB by altering the amplitude of the low l multipoles, dependent on the amount of inflation. Recently discovered CMB anomalies at low multipoles may be evidence for this. In our model we assume the spacetime is the product of a four-dimensional spacetime and flat extra dimensions. Before the compactification, both the four-dimensional spacetime and the extra dimensions can either be expanding or contracting independently. Taking into account physical constraints, we explore the observational consequences and the plausibility of these different models.},
doi = {10.1088/1475-7516/2017/04/034},
journal = {Journal of Cosmology and Astroparticle Physics},
number = 04,
volume = 2017,
place = {United States},
year = {Sat Apr 01 00:00:00 EDT 2017},
month = {Sat Apr 01 00:00:00 EDT 2017}
}
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