The Vikings announced today that they've signed former Raiders RB Latavius Murray, does this mean that there is no chance Adrian Peterson rejoins the team?

I believe the answer to that question is YES. I don't see any scenario where either the Vikings ask or Adrian accepts an invitation to sign a new contract and rejoin the team.

I don't think Murray would have signed with the Vikes if the team hinted that Peterson may return, Murray is in the prime of his career and doesn't need or probably want to share the spotlight with future Hall of Fame RB Peterson, and I don't think Adrian would want that either.

And if Peterson was really interested in working out a new contract with the Vikings, it would have happened by now.

The Adrian Peterson era is done in Minnesota. But he will play again somewhere I'm sure, it might be after the draft or maybe into the start of training camps, but I think he will be on a team when the new NFL season kicks off in September.