Does a law enforcement officer violate the Fourth Amendment by approaching an individual on the street or in another public place, and then asking him to answer the same questions?

[L]aw enforcement officers do not violate the Fourth Amendment by merely approaching an individual on the street or in another public place, by putting ques tions to him if the person is willing to listen, or by offering in evidence in a criminal prosecution his voluntary answers to such questions. Nor would the fact that the officer identifies himself as a police officer, without more, convert the encounter into a seizure requiring some level of objective justifica tion. The person approached, however, need not answer any questions put to him; indeed he may decline to listen to the questions at all and may go on his way. He may not be detained even momentar ily without reasonable, objective ground for doing so; and his refusal to listen or answer does not, with out more, furnish those grounds. If there is no deten tion no seizure within the meaning of the Fourth Amendment then no constitutional rights have been infringed. Florida v. Royer, 460 U.S. 491, 497-498 (1983) (citations omitted).