Here's one "big bang" theory that's been debunked: Kaley Cuoco and Johnny Galecki are not dating. On Wednesday, the 29-year-old actress posted a photo on Instagram of herself and her "Big Bang Theory" co-star giving each other a fist bump.

She wrote: "So sorry to disappoint, but no home wreckers or secret flings going on here. Me and @sanctionedjohnnygalecki are just the best of buds -- Leonard and Penny will just have to suffice!!!"

Galecki, 40, later posted to his Instagram account a photo of them on the same day with the caption: "No scandals/home wreckers/pregnancies here, y'all. Just profound friendship."

Rumors that Cuoco and Galecki were a couple started brewing after the actress announced her split from husband Ryan Sweeting last month. Cuoco and Sweeting were married on Dec. 31, 2013.

'Top Model' ending

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"America's Next Top Model" is about to leave the catwalk.

On Wednesday, host Tyra Banks posted the news on Instagram with a photo of the number 22 and a caption to tell everyone that Cycle 22 will be the final one for the reality series. "Yeah, I truly believe it's time," Banks, 41, posted.

The CW, which airs the show Fridays at 9 p.m., confirmed that the show will come to an end on Dec. 4.

Are you excited for parents-to-be John Legend and Chrissy Teigen? Go to

hollywoodlife.com and let us know.