We consider $d$ random walks $\big(S_n^{(j)}\big)_{n\in\mathbb{N}}$, $1\leq j
\leq d$, in the same random environment $\omega$ in $\mathbb{Z}$, and a
recurrent simple random walk $(Z_n)_{n\in\mathbb{N}}$ on $\mathbb{Z}$. We
assume that, conditionally on the environment $\omega$, all the random walks
are independent and start from even initial locations. Our assumption on the
law of the environment is such that a single random walk in the environment
$\omega$ is transient to the right but subballistic, with parameter
$0<\kappa<1/2$. We show that - for every value of $d$ - there are almost surely infinitely many times for which all these random walks, $(Z_n)_{n\in\mathbb{N}}$ and $\big(S_n^{(j)}\big)_{n\in\mathbb{N}}$, $1\leq j \leq d$, are simultaneously at the same location, even though one of them is recurrent and the $d$ others ones are transient.

Este artículo explora los viajes en el tiempo y sus implicaciones.

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