Nobel laureate Robert Yisrael Aumann gave a boost to the fledgling Ahi Party of MKs Effi Eitam and Yitzhak Levy on Tuesday when he announced that he was joining. Ahi, which is an acronym for "land, society and Judaism," changed its name from the Religious Zionist Renewal Party two weeks ago. The party ran as part of the National Union-National Religious Party in the last election. It recently embarked on a membership drive and encouraged other parties in the National Union to do the same. Aumann, 77, does not intend to run for Knesset with the party, but is expected to be involved in writing its platform on diplomatic and security issues. He wrote a letter calling upon people to join him in the party. "For more than a decade, we have been stuck in a deep and difficult leadership crisis," Aumann wrote. "Good people have come and gone and everyone without exception left us with a deep feeling of disappointment and a loss of direction on issues of national and personal security, education and values. There is a feeling that our leaders deepened national rifts is order to achieve narrow political gains for themselves." Aumann, an expert in game theory, won the Nobel Prize in Economics in 2005 for his work on conflict and cooperation through game-theory analysis. He is a professor at the Center for the Study of Rationality in the Hebrew University of Jerusalem.