I rewatched “Interstellar” and the time dilation dilemma makes my brain hurt. If a change in gravity alters time then wouldn’t you feel a difference entering/exiting said fake planet?
In: Planetary Science
Here’s a short animation that reviews relativity.
(Read below before watching for some frame of reference, so to speak)
My notes for you:
This is NOT an easy topic – and I don’t know if an ELI5 could even exist. More like ELI25… but having studied physics I can probably give a little info.
Let’s start with this…. As you go faster, your time moves more slowly than that of an observer. While YOU don’t experience it, more time will have elapsed for the person you left behind (the observer)). You come back to them, they have aged more than you.
It’s not actually the SPEED that’s causing the time dilation, rather the ACCELERATION. (I know you asked about gravity, stick with me here)…
So, as you accelerate, **your time is moving more slowly**. *(And for BONUS fun, check this out… as you approach the speed of light… that is to say, accelerate towards the speed of light,.. not only does your TIME slow down, but you also become more MASSIVE… And if that’s not enough for your brain… You actually SHRINK in the direction you are moving. All to an outside observer. You feel nothing and experience nothing other than the force pressing against your back as you accelerate.)*
Wild stuff.
OK… Now, how does this tide to the MOVIE? …soon. Just one mote foundational brick:
Acceleration and gravity are indistinguishable forces. In fact, they are the **SAME force**. Gravity is YOUR mass accelerating downwards towards a more MASSIVE body. In the case of somebody standing in their house… That “more massive body” is the earth that they are accelerating towards the center of. The reason why they are not *going* to the center of the earth is because the floor stops them.
When you are in a strong gravitational field… It is *exactly* the same as fast acceleration. And in the case of a movie, enough acceleration… A.k.a. gravity… for their time to dilate significantly.
The presumption being their mothership is far enough away from the black hole as to not experience that same dilation, or not to that magnitude.
The movie is correct in the interpretation of General Relativity.
Whether you could get on a planet with such a proximity to a black hole is **another matter entirely**. But the physics… it’s actuate. In fact, Neil deGrasse Tyson guest started on a CinnemaSins video to corroborate (or refute) the science.
It’s a good watch. And far more fun than the first link.
I’m sure it’s an awful ELI5 I’ve written, but if you can accept this, then you may be able to grasp it:
As you accelerate three things happen… (1) time slows down, (2) you gain mass and (3) you shrink in the direct of movement. This is tested. It’s accurate. It’s insane. And beautiful – as science tends to be. 🙂
So long ad we understand that gravity and acceleration are the same force (with different causes) we can see how General Relativity can cause this dilation of time.
All that being said… to “understand” may aspects of physics… well, it may not be possible. Heck, look up Bell’s Theory / Bells Inequality. This is a insanely rested theorem that shows, with basically zero doubt that “non-locality” exists. And may not fry your brain quite yet, it if you descend into the about hole that is Quantum Physics, you will have your socks knocked clean off your feet.
That’s all I got for now. I can be clarify or share more details. Or even resources if you *would like to know more*.
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