Other Dimensions

I was watching NOVA earlier, too bad I only caught the final 10 minutes. It was all about string theory and also the hunt for other dimensions. If scientists actually proved that other dimensions existed, do you think they would be allowed to tell us? Assuming what we refer to as aliens exist, it could already be known that at least some of them come from other dimensions. Admitting other dimensions exist could be like opening a Pandora's box that "they" would rather keep closed. Just something I was pondering on.