CBS has renewed "The Big Bang Theory" for three additional seasons, guaranteeing that the geek-friendly sitcom will be on the air through at least the 2013-2014 season.

"It doesn't take a theoretical physicist to see why this show is a BIG part of our comedy future," CBS entertainment president Nina Tassler said in a statement.  "From ratings to critical acclaim to pop culture buzz, it's struck a chord on all levels. The creative genius of Chuck Lorre and Bill Prady and the on-camera talents of an amazing young ensemble have created a comedy that will entertain viewers for a long time.  We're proud to partner with Warner Bros. on another highly successful, long-running comedy."

Currently in its fourth season, "Big Bang Theory" moved this fall from Mondays to Thursdays - a night where no one but NBC has had success with comedy in many, many, many years - and has done very well, averaging 13.9 million viewers and a robust 4.7/14 rating/share in the advertiser-coveted demographic of adults 18-49.  

"Big Bang" star Jim Parsons won an Emmy in the fall for Outstanding Lead Actor in a Comedy Series, and the show's actors all recently received big raises, with the leads slated to get up to $350,000 per episode in that 2013-14 season.