In physics, time is defined as “the measure of a change in a physical quantity or a magnitude used to quantify the duration of events,” but, to many physicists, while we experience time as psychologically real, it’s not fundamentally real.
When I told that to a friend recently, she said “bullshit” and I understood. The idea that time might not be real is so alien to our finite minds and so counterintuitive that it’s hard to comprehend. And yet…I’m fascinated by this concept.
Of course, what “reality” is depends on what “time” is. Is time irreducible, fundamental, an ultimate descriptor of reality? Or is our subjective sense of flowing time, generated by our brains that evolved for other purposes, an illusion?
Many physicists and philosophers now suspect that time is not fundamental, but emerges out of something more fundamental — something non-temporal, something altogether different (perhaps something discreet, quantized, not continuous, smooth).
The alternative, of course, is our common intuition: time flows, the present is superspecial as the only real moment, and the deep nature of reality is one of becoming.
If all this sounds crazy, think about time in your dreams. Does it exist?
Or think about how our minds work, flitting from this moment to something remembered to something anticipated, and back to the new moment we’re in after flitting back and forth in supposed “time.” Our minds don’t work in a straight line, yet we want to think of time as a straight line from here to there.
I’ve been thinking about time for a number of years now and following the physicists’ theories about time as they’ve evolved. I still can’t fully encompass the idea that time doesn’t exist outside our own brains and that we need to look in those brains to understand time, but as I look at my calendar and think about how I have to be at an appointment at 2 p.m. on Friday, it’s hard to think it’s not real.