Cosmologist

Billie needed to get her hair done. Her roots were showing, and the split ends were coming back.
But her regular cosmetologist was booked. And couldn’t fit in any walk-ins.
So, Billie went to a cosmologist.
“Of course I have time for you,” said the cosmologist. “The earth is over four billion years old, and we believe that the universe is nearly fifteen billion years old. What’s a few minutes here and there?”
They discussed galaxies and quasars and pulsars and comets.
After several sessions, Billie’s hair was an absolute fright.
Which explains how Albert Einstein’s hair got that way.