A Potential Fountain of Youth for Comic Characters

I will admit it, Math was NOT my best subject. I was a History major for heaven's sake. My fantasy was to stand around wearing a corderoy blazer with leather patches on the elbows, and discussing the amazing fact that Geoffrey Chaucer was the brother-in-law of John of Gaunt. However, I did always like Science, especially Astronomy, Geology and of course, Paleontology. Watched Bill Nye the Science Guy with the kids, and was actually in the middle of the third episode of "Cosmos" while at the Hospital and GIVING BIRTH! I had a serious crush on Carl Sagan.

And it occurs to me, that in "Cosmos", it is stated that when you begin to approach the Speed of Light, strange things begin to happen, time-wise. Known as Time Dilation, as you approach the SoL, time slows down for you. If you left earth, and travelled at the Speed of Light, or even close to it, you would remain the same age, while everthing back on earth would have aged much faster. Or something.

So could DC and Marvel use this handy little conundrum to explain why characters don't age in relation to everyone else? It's great for the Green Lantern Corps of course, they are bopping around Spaaaaaace all of the time. All that high speed travel helps keep them young and peppy. Probably works for Superman too. I understand that there is a line of reasoning that the various Flashes age faster due to their enhanced metabolisms, but wouldn't the Time-Dilation theory work for them as well? Running at such super-speed would help slow their aging as well.

It could also work for just about any other character in the various universes. Spider-Man and Batman may not be cosmic heroes, but they do seem to get pulled into just about every inter-galactic brouhaha that seems to pop up, so maybe they get some benefit out of it.

Is this a workable theory, or are there any REAL science majors out there, who can blow a hole in this whole idea? I like it, mainly because that means that the Green Lanterns will be flaunting their taut, well-muscled buttocks throughout the universe for a very very long time.