Time and space

I know that you may be expecting a post on something educational, and I hope this is educational, but not in an “educational leadership” kind of way.  Since this blog is about my own learning, I wanted to share something cool I learned this week.  So here goes – hope you learn something too!

Sitting on the couch the other evening, browsing the channel guide, my husband says, “Hey, what’s on Nova?”  The topic:

Fabric: The Illusion of Time

How could we not watch THAT?  The next hour was spent getting my mind expanded by Dr. Brian Greene of Columbia University, a professor of mathematics and physics, and probably a great guest to have at a party.  Okay, yes, that’s the kind of party I’d love to go to.  (I’m not sure how people like him do it, but taking the most complex theories of physics and making them understandable to regular old humans is a fabulous skill.)

I learned two or three pretty amazing things that I just thought I would share.  My reasons are several: as an educator, I know that by teaching someone else (in this case, you!) one’s own understanding of concepts is deepened and cemented; as a sci fi geek I love thinking, talking, and writing about this kind of stuff; as a competitive person I want to see if I can do as good a job of explaining as Dr. Greene.  Good luck on that last one, but here goes:

1) Time is not a constant, fluid entity.  It is a personal perception based on the experience of the individual.

2) Time is affected by movement.  The effect at slow speeds is infinitesimal, but any object that is in motion experiences a slowing of time.  This was tested by putting an atomic clock in a plane and flying it across the globe, and comparing that clock to one that remained stationary on the ground.  The difference between the two clocks was billionths of a second (which atomic clocks are able to measure!) but there was a difference.

3) The idea of “now” is not fixed.  (This part blows my mind…)  The past, present and future all exist simultaneously, depending on our position in the universe and our movement.  You’d need to see the visual to really get this one – basically the universe and space/time is like a loaf of bread (no really!) – but you can read the transcript and try to visualize it yourself if you want to!  In essence, if I am in one spot in the universe and an alien is across the universe at another point, and we are both not moving, we may experience “now” as a slice across space/time at the same “time”.  BUT – if the alien is moving, then his “now slice” is angled, either towards my “past” or “present” and so we may experience “now” at different “times”.  I am using way too many quotation marks here!

4) Using the ideas above, time travel may be possible, if you can build a vehicle that can expand travelling very close to a black hole (to travel to the future), as gravity as a force slows down time.  So if I travelled to a black hole and spent a few hours there, and then returned to Earth, what I may have experienced as a few hours may have been decades on Earth.  I would not have aged much but everyone else would – in essence, I would be in the future.  Wormholes are another theoretical way that time travel might be possible, but I’m just going to say that I don’t get them at all.  Hey, I can’t learn EVERYTHING in one hour!

So, I hope you learned something geeky about space/time today, and maybe you’ll tune in yourself to the next installment of the “Fabric of the Cosmos” series.  I may even try to jump in and join the #nova chat during the episode if I am brave enough.  Whatever happens, I am feeding my inner learnivore!