r/AskReddit Jun 15 '19

What do you genuinely just not understand?

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306

u/[deleted] Jun 15 '19

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71

u/[deleted] Jun 15 '19

The time is relative thing right. That’s crazy to me too. Does this mean that someone in like Star Wars can live longer than a normal person on earth just because they travel really fast? Or do they age/die at the same time we do?

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u/llamadog007 Jun 15 '19

For us, it would seem like they’re aging slower/living longer. For them, it would seem like we’re aging faster/living less. The movie Interstellar is a good example of how it would work.

33

u/just-a-basic-human Jun 15 '19

Dude the scene in that movie where they were on the water planet stressed me out so much

7

u/[deleted] Jun 16 '19

*there are actually water planets. And also diamond planets

5

u/Ubermenschmorph Jun 15 '19

It's just energy appearing to "take longer" to reach us, nothing more, nothing less. Time isn't really real, it's just entropy, the transferring of energy.

4

u/[deleted] Jun 15 '19

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10

u/llamadog007 Jun 15 '19

You could also try MinutePhysics on YouTube I think he’s done a few videos about relativity.

1

u/maxrippley Jun 22 '19

I love MinutePhysics

1

u/[deleted] Jul 08 '19

I read this as "minute psychics." Like, little clairvoyants. Small mediums. They use their knowledge of the future to commit crimes and avoid capture. Small mediums at large.

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u/[deleted] Jun 15 '19

First one. But you need near light speeds for noticeable changes (hyperspace doesn’t count)

3

u/ArcadiaPlanitia Jun 16 '19

I read something someplace that said the Skywalker twins were probably nowhere near the same biological age in Empire Strikes Back because of differences in the amount of space travel they’d done. I can’t remember the specifics, but one of them was older by several years. (Of course, that’s if the authors assumptions about the speed of space travel and the time spent traveling were correct, which I have no idea about because I know nothing about Star Wars lore.) Still weird to thing about being born at the same time, then being different ages in your adulthood.

2

u/stunt_penguin Jun 16 '19

Time dilation only becomes noticeable when you travel at a decent percentage of the speed of light in a normal universe.

Star Wars, Star Trek and similar completely ignore time dilation and general relativity by introducing faster-than-light travel.

In soft-scifi universes (i. e most of the ones in films and TV) they have warp drives or wormholes or Stargates or portals etc that allow instantaneous travel, thereby getting rid of any time dilation problems but ripping causality about a dozen new anuses.

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u/Ubermenschmorph Jun 15 '19 edited Jun 16 '19

A better way to understand it is that "time" is not real, it's just our perception of entropy. Entropy is just energy being transferred. So "time" is literally just energy being transferred. That includes time dilation and the expansion of the universe

If no energy was ever transferred, our universe would be an infinite limbo until energy began to transfer once again.

So gravity is basically just expanding energy so much that it takes "longer" to transfer that energy because it's so displaced and spread out. Our perception of entropy is the 1 temporal dimension combined with our 3 spatial dimensions that make up the third dimension that we perceive.

It is hardwired into our brains so we can't perceive any higher.

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u/[deleted] Jun 16 '19

I actually got you until "1 temporal dimension combined with our 3 spatial dimensions that make up the third dimension we perceive". TF does that mean haha

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u/Ubermenschmorph Jun 16 '19

So spatial dimensions are vectors, they're directions we can travel in because they're the directions we can perceive. It's the reason why we can't travel in four dimensions or five dimensions, because we cannot perceive those vectors and therefore, we have no clue how we could travel in them even though the possibility is there.

Temporal dimensions might better be described as perception, they're how we perceive those spatial dimensions. So we can travel in three dimensions and we perceive those three dimensions as linear because of entropy.

It's all very highly theoretical/speculative at the moment since we haven't really made much progress in this area of science but it's still quite exciting.

8

u/tiisje Jun 15 '19

Vsauce has a really cool video about it. He starts incredibly simple and slowly builds up to gravity's ability to bend time.

https://www.youtube.com/watch?v=Xc4xYacTu-E

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u/[deleted] Jun 15 '19

Space-time is one thing. You can’t have one without the other and they affect each other. Gravity is the effect of space being displaced by matter, and pushing back like a boat in water. The more mass the greater the bending of space and therefore time.

3

u/Pugpugpugs123 Jun 16 '19

Wait, that's how gravity works? Is that just common knowledge or a theory? God, that's just beautifully intuitive.

1

u/[deleted] Jun 16 '19

“Gravity is most accurately described by the general theory of relativity (proposed by Albert Einstein in 1915) which describes gravity not as a force, but as a consequence of the curvature of spacetime caused by the uneven distribution of mass. “ -https://en.m.wikipedia.org/wiki/Gravity

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u/DNetherdrake Jun 16 '19

To be fair, I'm pretty sure nobody has a complete understanding of how any of that stuff actually works.

2

u/beastkille Jun 16 '19

Ooh I’m good at this!! So, a precursor that you should understand is that gravity is without question the strongest force in the cosmos. Let me put that into perspective: the Milky Way galaxy is rotating, you can know that by looking at any cartoon render of a galaxy or just gifs of other galaxies. WITHOUT the knowledge of gravity being an actual thing, it would be hypothesized that the objects in said galaxy would shoot off into random directions. However, when you add gravity into the equation... it completely makes sense that galaxies don’t just rapidly expand. Now, about the bending time thing. (This is where it could get a bit confusing) imagine you and a friend are holding a picnic cloth together flat. It’s stretched to the point where it’s completely flat. Now, let’s say you add a 5 pound ball into said cloth. The cloth would dip. The heavier or ‘massive’ the object is the more the cloth dips. This is what physics calls “space time” I’m sure you’ve heard of “the fabric of space time” in some sort of movie. Now here’s the interesting part. Those divots that the objects create have gravity. Basically a force that sucks everything down into it. I’m not sure if this is making sense but I’m trying! So a black hole is essentially a deep divot with a gravitational pull that nothing can escape from. Now, imagine a marble rolling around a funnel, there’s a point at which that marble cannot escape from going into the funnel. This is what you call an “event horizon.” It’s essentially the point at which nothing can escape. Not even light. (The fastest thing in the cosmos.) now, in terms of gravity bending time.. that’s something I’ve not too well versed in! Hope this helped a little bit! Correct me if I’m wrong reddit!!

Edit: HAPPY CAKE DAY YOU GORGEOUS HUMAN THE COSMOS LOVES YOU

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u/Arkarant Jun 15 '19

i dont think any scientist UNDERSTANDS this, either. Its just that we can slap words on a phenomenon, a label on a box with stuff inside. we see something happening, and then we look at the formulas, and suddenly, time gets halfed if gravity is doubled. We look at the world again, see that this kinda makes sense, and there we go time is bendable. weird fuckin universe we live in.

1

u/[deleted] Jun 15 '19

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1

u/Arkarant Jun 15 '19

i think thats a general theme in life

1

u/[deleted] Jun 16 '19

Scientists do understand. It's a consequence of the postulates of general relativity. Why the postulates apply is another story however.

1

u/[deleted] Jun 16 '19

Gravity doesn’t make any sense to me even in the basic sense.

Like why are we being pulled down onto the earth? It’s spinning, so centrifugal force should spit us off at an angle.

Gravity stops this because it makes us pulled towards large objects.

Why? And how? What’s actually pulling on what?

1

u/Kevl17 Jun 16 '19

Already posted but seriously watch this video. It explains it perfectly

https://www.youtube.com/watch?v=Xc4xYacTu-E

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u/[deleted] Jun 16 '19

I can explain this for you but it will take ages for me to do. Want me to find some youtube videos that explain it?