in the play Hamlet by william Shakespeare, are there something rotten in the state of Denmark? and who responsible for that?

Hamlet's father has been murdered.

This site will help you with understanding the play.

http://www.sparknotes.com/shakespeare/hamlet/

Yes, in William Shakespeare's play Hamlet, there is a reference to "something rotten in the state of Denmark." This phrase is uttered by Marcellus in Act I, Scene IV. It suggests that there is corruption and deceit lurking beneath the surface of the Danish kingdom.

The person responsible for the underlying corruption can be attributed to Claudius, the current king of Denmark. Claudius is Hamlet's uncle who has recently married Hamlet's mother, Gertrude, following the death of Hamlet's father, King Hamlet. Claudius killed his own brother, King Hamlet, in order to take the throne and marry Gertrude.

Throughout the play, Hamlet becomes obsessed with seeking vengeance for his father's murder. He suspects Claudius and plans to expose his guilt. Hamlet's suspicions and actions contribute to the sense of something rotten within the kingdom. Additionally, the play portrays a diseased political system where betrayal, deceit, and moral corruption prevail. Thus, the responsibility for the corrupt state of Denmark can be largely attributed to Claudius, but the play suggests that corruption is also deeply ingrained within the entire political structure.