Rajesh, Ph.D. – Rajesh, who originally comes from New Delhi, India, works as a particle astrophysicist at Caltech. He is very shy around women and is physically unable to talk to them unless he drinks alcohol. However, he has had much better luck with women as opposed to his overly confident best friend Howard. His parents are often seen via webcam. In three of them, he is the only one who don’t have a girlfriend.
Jim Parsons as Sheldon Cooper, Ph.D. – Originally from East Texas, he was a child prodigy, starting college at the age of 11, right after completing the fifth grade. As a theoretical physicist, he possesses a master's degree, two Ph.D.s, and an IQ of 187. He exhibits a strict adherence to routine; a lack of understanding of irony, sarcasm and humor; and a complete lack of humility. These characteristics are the main sources of his character's humor . It sounds crazy that a man like Sheldon should have a girlfriend