Raj: What are you drawing over there?
Sheldon: It's a hypothetical containment field for a Frisbee-sized wormhole that could serve as a portal to a parallel universe.
Howard: Oh, you silly doodlebug.
Leonard: You know, a lot of scientists believe that making contact with other life-forms would probably not end well for us.
Sheldon: It's a Frisbee-sized wormhole, Leonard. You can block it with a Frisbee. Calm down.