California-based autonomous driving technology company Waymo started training its self-sufficient cars in Nashville this week. But picking Music City passengers up in them may be far in the future.

Billionaire Bill Ackman is the CEO of Pershing Square Capital Management, a hedge fund that returned 210% in the past five years. Comparatively, the S&P 500 ( ^GSPC -1.12%) advanced 101% during the ...