Prime Minister Shinzo Abe's administration has a habit of co-opting Nobel Prize-winning economists when it lays the groundwork for contentious policy decisions.
It's not surprising then that the visit of Christopher Sims, a professor at Princeton University, has ignited speculation in Japan that the government may be looking to soften its deficit reduction targets or yet again postpone a hike in the consumption tax.
Sims sees monetary policy as constrained by interest rates having hit rock bottom and advocates that the government step into the breach with expansionary spending.