[quote=@Legend]
<Snipped quote by Multifarious>

How did you test something like that?
[/quote]

Well, you don't send people through first, that's for sure. Cheap drones programmed to go through, scan what it can and collect data about the other side, and return. So we knew if it didn't return, it didn't work. Or, if it did but with data about our own universe, then it also didn't work.