Blackstone will invest $500 million in privately held Resolution Life and help it raise roughly $2.5 billion. Blackstone will manage Resolution Life’s illiquid investments in areas such as private credit, private real estate and asset-based finance. The arrangement will add as much as $25 billion to the private-equity firm’s assets under management in the first year and is expected to contribute a total of more than $60 billion over the next six years.