Backed by more than $6 billion in venture capital, the millennial-aged leaders of Aging 2.0 are searching the world over for start-up companies with the best ideas on improving the lives of aging people. In Minnesota, John Fraser is now leading the charge, as a volunteer for San Francisco-based Aging 2.0. In his day job, Fraser, 34, is chief technology officer of Edina-based senior health care services company Lifesprk. A week and a half ago, Fraser launched the state’s first Aging 2.0 chapter with a “pitch event” in Bloomington. Four start-ups presented their cases in hopes of eventually winning access to global capital and expertise through Aging 2.0. Since its founding in April 2012, Aging 2.0 has identified about a dozen companies to partner with its Generator Ventures funding arm.