Every once in a while, science throws us a tiny factoid about the nature of time that makes us want to lie down on the floor and stop thinking thoughts for a while. You know, like how what we call “now” is actually 80 milliseconds in the past, or how the stars you see at night have already died by the time their light reaches us here on Earth (although that one is greatly exaggerated according to Phil Plait). Well, here’s a new one for you: light photons don’t experience time. Like, at all.
We first learned about this from Frasier Cain of Universe Today, who heard about it from astronomer Dr. Pamela L. Gay while taping an episode of their weekly podcast, the Astronomy Cast. Cain explains in the below video:
The important point comes in at 0:23 or so. “From the perspective of a photon,” Cain says, “there is no such thing as time. It’s emitted, and might exist for hundreds of trillions of years, but for the photon, there’s zero time elapsed between when it’s emitted and when it’s absorbed again. It doesn’t experience distance, either.”
He goes on to explain that this is due to the time-bending nature of the Theory of Special Relativity. The closer you get to light speed, the less you experience the physical effects of time — meaning that if you were to spend 10 years zooming around in space at the speed of light, everyone you left behind on Earth would be ten years older by the time you got back, and you would look exactly the same. (This is the plot of Flight of the Navigator.)
However, light is always traveling at light speed — that’s kind of it’s thing — so it’s never affected by time. Nor is it affected by distance, because as the Special Relativity Theory and the best episodes of Doctor Who both note, space and time are inexorably linked to one another.
Speaking of Doctor Who, if we’re going to bring this into geeky psuedo-science fiction territory (and of course we will, because have you seen the name of this website?) then obviously it means that all we need to do to be immortal is harness the power of light to ensure we never age. Huh, maybe those guys from Dark Souls weren’t so far off after all with their Sun worship. If only we could all be so grossly incandescent!
(via Phys.org, image via Marjan Lazarevski)
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