Info about black holes and/or parallel universes plz?

These are two topics Ive read about and seem really interesting. Ive read a lot about black holes but discoveries just keep on coming and I havent read anything recently. Also parallel universes is a theory i read about but it was only one article. I would just like to kwon some authenticbsites or sources I could find rly awesome info about these things, for example, the site of a popular science magazine. I dont read a lot of tht but suddenly i got the urge to learn more about tht.