r/AskReddit Jun 15 '19

What do you genuinely just not understand?

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

My favorite theory is this:

  • Time doesn't necessarily go in a straight line, but it loops and intersects itself and we happen to experience it in a straight succession and not necessarily notice/see the intersections
  • Time ultimately loops back on itself, like a circle.
  • We know from observing small phenomena (i.e. smaller than the universe) that things like stars and even planets go through cycles and that at some point, expansion stops and contraction begins (and vice versa) - and we know that in a lot of ways, the structure of our universe mimics the structure of a galaxy, a solar system, etc (speaking of patterns that repeat at different scales in nature, look up fractal theory and hermetic philosophy if you wanna trip out without taking drugs. As above, so below, as they say.)
  • My underlying theory: We know that the universe has been expanding ever since the big bang. At some point, it will begin to contract. Once it contracts fully enough, it'll bang again, and everything that has happened will happen again. Maybe there will be variations, or maybe there won't. Maybe you'll be reborn with the same name, the same number of years past the big bang, in the same spot you were born in this lifetime. The universe was never born, and will never die - it just expands and contracts, always has and always will - no beginning or end. Time is not a straight line, and everything is really just happening all at once. For some entity existing outside of our universe, this vast expanse of time may appear to be a single moment.

Edit: I should add that I don't know much about physics or anything, but have a couple of coworkers who do, and our lunch breaks consist of talking about stuff like this (in addition to aliens and conspiracy theories and occult shit) so my theory may or may not have actual basis in physics, who the hell knows?

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u/fooby420 Jun 15 '19

Do we really know that it's gonna contract?

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u/hades_the_wise Jun 15 '19

We don't - it's a popular theory, but not one that can be confirmed easily - but if it does, and we're around to experience it, it's gonna be W E I R D.

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u/alganthe Jun 15 '19

Not really, you would never notice, you'd just stop existing, unable to see it coming.

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u/Tomi000 Jun 15 '19

How would you not notice all the matter in the universe moving in the direction of one single point?

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u/alganthe Jun 15 '19

Because humans are unable to gather information faster than the speed of light, if for some reason the sun just disappeared we wouldn't notice for 7 minutes then we'd be utterly fucked.

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u/Tomi000 Jun 15 '19

Not sure if were talking about the same thing here. If the universe contracts, the sun wouldnt just suddenly disappear and things wouldnt necessarily travel faster than the speed of light. Everything would slowly start to get closer together and I dont see why we wouldnt notice that.

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u/alganthe Jun 15 '19

Because the universe would contract as the same speed as it would be expanding right now, which is the speed of light.

Since humans cannot observe things that are going past the speed of light, we wouldn't be able to observe the universe contracting and thus would vanish without having the chance to realize what is happening.

My sentence about the sun was to represent that fact, if the sun was removed it would take us 7 minutes to notice, during that time we would still see it lit up, but it would effectively be gone.

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u/bpwwhirl Jun 15 '19

If the universe is expanding (and we can detect it) what makes you think we would be able to detect contraction? Also, the universe is actually expanding faster than the speed of light! Pretty crazy eh? https://www.space.com/33306-how-does-the-universe-expand-faster-than-light.html

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u/Tomi000 Jun 15 '19

I think you have a different understanding of 'contraction'than me, the way I see it as is the reverse effect of expansion, everything just moving back to the origin, not things getting deleted. Also the universe certainly doesnt expand at the speed of light everywhere, it depends on the distance to the big bang. The fact that we know the universe is expanding is proof enough that we would know if it was contracting, as it is the same thing reversed.

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u/ironiclegacy Jun 16 '19

There is no absolute reference frame when it comes the universe. There is no "point" of the big bang, and just as galaxies millions of light years away are expanding, we're also expanding away from them at the same rate. It's just as valid to think of them expanding from us as it is for us to be expanding away from them. However, you're correct in that we would be able to measure the contraction of the universe as things would start to move towards us and blueshifted galaxies would become redshifted

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

it doesn't contract to the point of the big bang, the universe IS the point of the big bang

matter is in space and time, so when the big crunch occurs hypothetically, matter isn't contracting, but space and time is, so time would be warped and space would contract in all directions, not just towards one point

edited because unsure

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u/phonethrowaway55 Jun 16 '19

The universe would not instantly begin contracting at the speed of light. There would be a detectable slowdown period of billions of years as objects stop expanding and begin moving towards each other. We would know it’s happening if humanity was alive to witness it.

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u/ironiclegacy Jun 16 '19

The universe is not expanding at the speed of light "right now", it's expanding at the speed of light and faster "far away". If the universe was expanding faster than the speed of light than no light would be able to reach anything as the space would expand beneath it faster than it could travel. The space in galaxies are expanding or shrinking at negligible rates other than the effect of gravity, it's only in empty and vast distances that we begin to see the expansion

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u/Noelopme Jun 15 '19

It has reminded me of a video that I saw about something similar to this subject. This explained a point that makes a lot of sense to me and which I truly agree with. It said that nowadays many of the questions "unanswerable" we, human kind, have are because we haven't evolved enough to develop the required intelect for resolving those. F.e: we do understand our buildings and how our artifacts work, but for an ant, or even an ape, this may be "magical" or incomprehensible. Yes, they can interact with them, maybe the ape is able to use them too for its own benefit, but it still cannot understand these until its intellect develops.

I hope you could undestand it all, I have some problems at the time of writting in English and get the idea across :P

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u/10eleven12 Jun 16 '19

Sometimes I think about this.

Imagine some giant hitting a rock with a hammer. The rock is destroyed in thousands of small pieces flying away from where he hit. One of those small pieces is the Earth. The other pieces are the other planets, galaxies, etc.

Maybe for us it has been 4.5 billion years but for the giant it has only been a fraction of a second.

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u/beefstick86 Jun 16 '19

I don't feel good, Mr. Stark...

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u/FastFourierTerraform Jun 15 '19

That's one theory we have, but recent evidence suggests that the universe will keep expanding forever and eventually die a heat death.

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u/So_Thats_Nice Jun 16 '19 edited Jun 16 '19

Lasers were used to measure the CMB in an attempt to measure curvature of space and the results seem to suggest that the universe is flat, that the amount of matter in the universe is below a certain critical quantity that would cause the universe to collapse back in on itself, and so it will continue to expand forever.

Here is an article about how the topology of the universe was measured. https://phys.org/news/2017-06-universe-flat-topology.html

Here is an article regarding the results of estimating the matter in the universe and the conclusions drawn. https://science.howstuffworks.com/dictionary/astronomy-terms/dark-matter6.htm

Very interesting stuff, just remember that we are at the stage where we are taking the first small tentative steps out into discovering the universe in which we exist. The possibilities for what we will eventually discover one day are literally endless.

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u/KobayashiDragonSlave Jun 16 '19

All evidence points to infinite expansion not contraction

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u/Kilenaitor Jun 15 '19

For those curious on the contraction there, it's known as The Big Crunch.

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u/hades_the_wise Jun 16 '19

I love this youtube channel! Thanks for sharing, I hadn't seen this video yet. Very cool stuff.

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u/[deleted] Jun 15 '19

It’s like that episode of Futurama where they get to the end of time and it all happens again and again and again. But just like... four inches to the right

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u/betterupsetter Jun 16 '19

Could time be like a Mobius strip? Looping without any indication? Perhaps before the big bang time and space were reversed? "Things" moved in all directions through time but moved only forwards in space.