What is the physical meaning of time?

What is the physical meaning of time? is a question that physicists have asked themselves for centuries. George Ellis's answer is the subject of this feature article from the June issue of Discover magazine. "In his framework, set out in a series of highly regarded papers published from 2006 onward, Ellis retains four-dimensional space-time, in line with relativity’s predictions. However, he argues that Einstein took that concept too far. There’s no need to assume that the fourth dimension must already exist out into infinity. Thus Ellis’ model has one crucial difference from Einstein’s: The future boundary does not encompass all that will ever happen."

Thanks for the late night reading! ;)

Article:
http://discovermagazine.com/2015/june/18-tomorrow-never-was

#time   #physics   #relativity