Is Will Turner and Elizabeth Swann in the Pirates of the Caribbean 4?

I haven't seen the movie yet and I really like the Pirates of the Caribbean series. Many people say that 2 of the main characters in the other movies of the series are not in the new sequel On Stranger Tides(Meaning Will Turner and Elizabeth Swann). Please no spoilers to the movie but I need to know are they in the new installment of Pirates of the Caribbean? Thanks for your answers.