Now showing items 1-5 of 5

  • Clustering of quintessence on horizon scales and its imprint on HI intensity mapping 

    Duniya, Didam G.A.; Bertacca, Daniele; Maartens, Roy (IOP Science, 2013)
    Quintessence can cluster only on horizon scales. What is the effect on the observed matter distribution? To answer this, we need a relativistic approach that goes beyond the standard Newtonian calculation and deals properly ...
  • Matter bispectrum in cubic Galileon cosmologies 

    Bartolo, Nicola; Bellini, Emilio; Bertacca, Daniele; Matarrese, Sabino (IOP Science, 2013)
    In this paper we obtain the bispectrum of dark matter density perturbations in the frame of covariant cubic Galileon theories. This result is obtained by means of a semi- analytic approach to second-order perturbations ...
  • The observed galaxy bispectrum from single-field inflation in the squeezed limit 

    Koyama, Kazuya; Umeh, Obinna; Maartens, Roy; Bertacca, Daniele (IOP Publishing, 2018)
    Using the consistency relation in Fourier space, we derive the observed galaxy bispectrum from single- eld in ation in the squeezed limit, in which one of the three modes has a wavelength much longer than the other two. ...
  • Probing the imprint of interacting dark energy on very large scales 

    Duniya, Didam, G. A.; Bertacca, Daniele; Maartens, Roy (American Physical Society, 2015)
    The observed galaxy power spectrum acquires relativistic corrections from light-cone effects, and these corrections grow on very large scales. Future galaxy surveys in optical, infrared and radio bands will probe increasingly ...
  • Testing gravity using large-scale redshift-space distortions 

    Raccanelli, Alvise; Bertacca, Daniele; Pietrobon, Davide; Schmidt, Fabian; Samushia, Lado; Bartolo, Nicola; Doré, Olivier; Matarrese, Sabino; Percival, Will J. (Oxford University Press, 2013)
    We use luminous red galaxies from the Sloan Digital Sky Survey (SDSS) II to test the cosmological structure growth in two alternatives to the standard cold dark matter ( CDM)+general relativity (GR) cosmological model. ...