Spontaneous isotropy breaking: a mechanism for cmb multipole alignments

By C. Gordon, Wayne Hu, D. Huterer, T. Crawford. 2005

168 citations recorded by the source corpus.

We introduce a class of models in which statistical isotropy is broken spontaneously in the CMB by a nonlinear response to long-wavelength fluctuations in a mediating field. These fluctuations appear as a gradient locally and pick out a single preferred direction. The nonlinear response imprints this direction in a range of multipole moments. We consider two manifestations of isotropy breaking: additive contributions and multiplicative modulation of the intrinsic anisotropy. Since the Wilkinson microwave anisotropy probe (WMAP) exhibits an alignment of power deficits, an additive contribution is less likely to produce the observed alignments than the usual isotropic fluctuations, a fact which we illustrate with an explicit cosmological model of long-wavelength quintessence fluctuations. This problem applies to other models involving foregrounds or background anisotropy that seek to restore power to the CMB. Additive models that account directly for the observed power exacerbate the low power of the intrinsic fluctuations. Multiplicative models can overcome these difficulties. We construct a proof of principle model that significantly improves the likelihood and generates stronger alignments than WMAP in 30%-45% of realizations.

Subfields: Astronomy and Astrophysics, Nuclear and High Energy Physics

View Paper: https://www.semanticscholar.org/paper/9985d0cf8138ee07ebd28c03d30d4b7196fa24ee

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

1. E. Komatsu
2. A. Banday
3. K. G'orski
4. H. Eriksen
5. David N. Spergel
6. Mark Halpern
7. C. Bennett
8. J. Weiland

In Nuclear and High Energy Physics

1. E. Komatsu
2. D. Schwarz
3. A. Banday
4. David N. Spergel
5. Mark Halpern
6. C. Bennett
7. J. Weiland
8. Gary F. Hinshaw

Citations in the corpus

• Accelerating Cosmologies with an Anisotropic Equation of State (2007, background): “According to whether this occurs at an early time or at late times, one may classify the models into those in which an originally isotropic CMB fluctuation is distorted on its way to us [9] and into those whose statistical anisotropy is imprinted in the primordial fluctuations [10].”
• INCREASING EVIDENCE FOR HEMISPHERICAL POWER ASYMMETRY IN THE FIVE-YEAR WMAP DATA (2009, methodology): “Data model and likelihood The starting point for our analysis is the phenomenological CMB signal model first proposed by Gordon et al. (2005), d(n̂) = [1 + f(n̂)]s(n̂) + n(n̂).”
• POWER ASYMMETRY IN COSMIC MICROWAVE BACKGROUND FLUCTUATIONS FROM FULL SKY TO SUB-DEGREE SCALES: IS THE UNIVERSE ISOTROPIC? (2008, background): “Recent theoretical developments(Ackerman et al. 2007; Erickcek et al. 2008; Gordon et al. 2005) have proposed new mechanisms for generating the imprint of a preferred direction in the CMB.”
• No large-angle correlations on the non-Galactic microwave sky (2008, background): “As has been pointed out by Gordon et al. (2005), Rakić & Schwarz (2007) and Bunn & Bourdon (2008), any possible explanation of the multipole alignments that relies on an additive, statistically independent contribution to the microwave sky on top of the primordial one increases the significance of…”
• Large-Angle Anomalies in the CMB (2010, methodology): “Alternately, in the early universe, asymmetry in the stress-energy tensor of dark energy [69] or a long-wavelength dark energy density mode with a gradient in the desired direction [40], could both imprint the observed alignments via the integrated Sachs-Wolfe mechanism; but it is hard to see how th”
• FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: COSMOLOGICAL INTERPRETATION (2008, unknown): “…& Wandelt 2004; Eriksen et al. 2004; Eriksen et al. 2004; Eriksen et al. 2004, 2007a; Copi et al. 2004; Schwarz et al. 2004; Copi et al. 2006, 2007; Gordon et al. 2005; Bielewicz et al. 2005; Jaffe et al. 2005, 2006; Vielva et al. 2004; Cruz et al. 2005, 2006, 2007b,a; Cayón et al. 2005; Bridges…”
• SEVEN-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE (WMAP ) OBSERVATIONS: ARE THERE COSMIC MICROWAVE BACKGROUND ANOMALIES? (2010, background): “A theoretical model that predicts large-scale quadrupolar anisotropy was also proposed by Gordon et al. (2005).”
• Anisotropic dark energy: dynamics of the background and perturbations (2008, background): “According to whether this occurs at an early time or at late times, one may classify the models into those in which an originally isotropic CMB fluctuation is distorted on its way to us [9] and into those whose statistical anisotropy is imprinted in the primordial fluctuations [10].”
• POWER ASYMMETRY IN WMAP AND PLANCK TEMPERATURE SKY MAPS AS MEASURED BY A LOCAL VARIANCE ESTIMATOR (2014, unknown): “Gordon et al. (2005) suggested that the power asymmetry might be modeled in terms of a dipole modulation of the form ΔT T ∣ ∣ ∣ ∣ mod (n̂) = (1 + A n̂ · p̂)ΔT T ∣ ∣ ∣ ∣ iso (n̂), (1) where ΔT /T |iso and ΔT /T |mod are, respectively, the isotropic and modulated CMB temperature fluctuations along a…”