Final answer:
The statement is false. In 'Sir Gawain and the Green Knight,' Sir Gawain is alive and does not send a message from beyond the grave.
Step-by-step explanation:
The statement 'Sir Gawain is not alive but does send a message to him from the beyond' is categorically false. In the literary work called 'Sir Gawain and the Green Knight,' Sir Gawain is indeed alive and interacts with other characters. He embarks on a quest and encounters various challenges, including a confrontation with the Green Knight. There is no instance of him sending a message from beyond the grave.