how does polonius explain hamlets madness? are claudius and gertrude persuaded ?

Polonius thinks that Hamlet is crazy for his daughter's love. Polonius has forbid Ophelia to see Hamlet. Having cut off his access to her, Polonius thinks Hamlet has gone loony-tunes. I think Gertrude might have been convinced but Claudius is a bit too wiley (clever) for this lame explanation. Claudius wants more proof.