Vector dark energy and high-z massive clusters

Abstract: 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.