Billionaire hedge fund manager and influential investor Bill Ackman has publicly endorsed former President Donald Trump for the upcoming presidential election, promising a detailed explanation of his decision in a future post. What Happened: On Sunday, Ackman went on the social media platform X to announce his formal endorsement of Trump, telling his followers that his decision was made rationally and based on empirical data. “I am going to formally endorse @realDonaldTrump,” Ackman posted. “I assure you that I have made this decision carefully, rationally, and by relying on as much empirical …