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Testing gravity on large scales. The skewness of the galaxy distribution at z~1

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 نشر من قبل Christian Marinoni
 تاريخ النشر 2008
  مجال البحث فيزياء
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We study the evolution of the low-order moments of the galaxy overdensity distribution over the redshift interval 0.7<z<1.5. We find that the variance and the normalized skewness evolve over this redshift interval in a way that is remarkably consistent with predictions of first- and second-order perturbation theory. This finding confirms the standard gravitational instability paradigm over nearly 9 Gyrs of cosmic time and demonstrates the importance of accounting for the non-linear component of galaxy biasing to avoid disagreement between theory and observations.



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