Advice of Hawking

http://calnewport.com/blog/2017/01/11/stephen-hawkings-productive-laziness

“Bruce, here’s some advice: The problem with physics is that most of the days we don’t make any major headway (on our projects). That’s why you should do other stuff: listen to music, meet good friends. There’s one exception to this rule: If you find a solution for a given problem, you work 24 hours a day and forget everything else. Until the problem is solved in its entirety.”