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Vector dark energy and high-z massive clusters

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 نشر من قبل Edoardo Carlesi Mr
 تاريخ النشر 2011
  مجال البحث فيزياء
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The detection of extremely massive clusters at $z>1$ such as SPT-CL J0546-5345, SPT-CL J2106-5844, and XMMU J2235.3-2557 has been considered by some authors as a challenge to the standard LCDM$;$cosmology. In fact,assuming Gaussian initial conditions, the theoretical expectation of detecting such objects is as low as $leq 1%$. In this textit{Letter} we discuss the probability of the existence of such objects in the light of the Vector Dark Energy (VDE) paradigm, showing by means of a series of $N$-body simulations that chances of detection are substantially enhanced in this non-standard framework.

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