I recently read this article on the new "House of the One". The building will feature three separated spaces for prayer: a mosque, a church, and a synagogue. There will be a central courtyard, but each religious space will be completely free of the icons/characteristics of the other. Is it permissible to daven in the synagogue part of the "House of the One"?
NOTE: I am aware that the rabbi who will be overseeing the shul part of the "House of the One", Tovia ben Chorin, is a Reform rabbi, and that there is an entirely separate issue about the permissibility of davening in a Reform shul. However, I am asking this question to see about the issues with the mosque and the church in the same complex, not with davening Reform, so for the sake of argument, please pretend that the shul is Orthodox.
Inspired in part by this question:Praying in "multifaith spaces" in airports and other institutions