Gravitational Time Dilation

Free form posts are always the hardest because I never know what to write.  It's one of those "water, water everywhere, but not a drop to drink" problems.  So, instead of writing my blog posts the other day, I decided to procrastinate by watching Stargate (SG1, otherwise known as the best Stargate) and there was a great episode on gravitational time dilation.

In the episode, the team opens the Stargate to a planet whose galaxy is actually being eaten by a black hole.  The strong gravity from the black hole comes through the Stargate and affects the compound here on earth.  The cool part is that because the compound is now experiencing such strong gravity, time inside the compound starts to move more slowly than time outside it.

I wanted to know if this was in any way realistic, so I did some googling!

The simple answer is: yes.  Time fluctuation die to gravity is actually a thing that happens in real life.  Albert Einstein predicted in his theory of General Relativity and it has since been tested that if two observers are standing in two regions with different gravitational potential, time will actually move faster for one than for the other.

They tested this by placing atomic clocks at two different elevations.  It took a while, but the clock at the higher altitude (which had more gravitational potential) eventually got ahead of the one at a lower altitude.  Basically, the closer something is to a massive body, the slower time will move (or the slower it will appear to move when viewed by someone further away from that massive body.

This works with black holes because when people watch something fall into a black hole, it takes a very long time.  Once something crosses the event horizon--even light--it can't escape, so observers see something very similar to one of those penny funnel things.

This makes it look like time is slowing down.  

So, was Stargate right?  In a loose sense, yes.  For distant observers, time does appear to slow down in regions close to very massive objects, like black holes.  But if you take into account their solution to the problem--Replicators, devices used to speed up time--they are completely wrong.  

But that will never stop me from watching the show.