The state retirement fund’s new chief investment officer has pitched the plan, which involves investing up to $20 billion more in private companies, as a way to help the $350 billion fund avoid sinking deeper into debt. … The plan sets up a new approach to the private equity market, which generally involves buying private companies, making them more profitable and then selling them at a gain. That could mean CalPERS’ partners in the endeavor would be involved in cutting costs and laying off workers at private companies. … Fund managers would work with CalPERS, but would not be public employees.