There are a lot of rumors, speculations and crazy tales about the dead Iranian physicist. I suspect this guy probably wanted to defect and so the regime killed him before he could do so. Now the Mullahnazis can blame it on the evil Zionists, old American Satan or even the British squirrels (like the one they snatched at the border).
Whatever it is, the signs of a crumbling regime are ever more presents and in plain sight. It's believed that 27 Iranian diplomats have resigned their posts in various countries and sought asylum since June 09. The cracks are getting larger and larger.