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The Universe is a forum for discussion of topics relating to Astronomy, Astrophysics & Cosmology

This subreddit is for all discussions, news stories, and science related to general astronomy, astrophysics, & cosmology.

The Universe is a forum for discussion of topics relating to Astronomy, Astrophysics & Cosmology

This subreddit is for all discussions, news stories, and science related to general astronomy, astrophysics, & cosmology. New to the Universe? Read our subreddit rules before posting! Submission Rules

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We like questions, news, published research, course content, educational resources or videos about astronomy, astrophysics, & cosmology.

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Ensure that you have the knowledge required to answer the question at hand. We are not strict on this, but will absolutely not accept assertions of pseudo-science or incoherent / uninformed rambling. Answers should strive to contain an explanation using the logic of science or mathematics. When making assertions, we encourage you to post links to supporting evidence, or use valid reasoning.

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Universe is a serious education/research/industry-based subreddit with a focus on evidence and logic. We do not allow unsubstantiated opinions, low effort one-liner comments, memes, off-topic replies, or pejorative name-calling.

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What if we are collateral damage?

I have a theory.

We know the universe is expending. Therefore, we can assume it had to start from somewhere.

But what if we are collateral damage of the explosion?

What if our universe is collateral damage of another Universe having exploded?

What if the stars around us are the initial damage and that eventually, the heat shock and friction will reach our world?

All explosions eventually burn up

So we can assume our explosion has only just started and that we will eventually burn up or die from having no more heat in the universe because everything around us that could give us warmth is gone.

Just a theory. I’m not a scientist. Just some guy with a theory that has probably been thought of before me.

19:55 UTC


Emergence is a Non-Zero-Sum Game

10:14 UTC


Our brain constructs our reality using a concept we call Time?

Time is the speed of motion of objects. Our brain can only observe objects that move at relatively the same speed. This is what we call our reality.

1 Comment
07:15 UTC


What if the universe is inside a multiverse

HEAR ME OUT ALR. My idea is that the universe is inside of a multiverse made of millions of other universes beyond that it just keeps becoming bigger and bigger with multiverses inside of multiverses until it reach’s this boundary I call the the final stretch the reason so is at this point reality and matter stretches so far that it creates a vortex that destroys the fabric of space and if you attempt to go through it you be slowly striped of every qaurk and soon after even the qaurks will stretch eventually destroying them and making everything -infinite mass bassicly destroying anything that enters it

Go ahead prove me wrong I ain’t no scientist but that’s my idea

19:22 UTC


Please help explain to me how Jupiter and Saturn is 100% gas?

I just don't believe it. i believe it's covered in gas yes. Most planets are but i do think all the planets inn our solar system are made if mass we can stand on.

Now I'm just stating this because I'm having a hard time understanding how we know they are 100% gas and how we got to the conclusion that that is what they are.

Please help me understand.

18:57 UTC


Help me understand

I need to tell Redet about something that has been going on for a long while and I just thought it was me being crazy first I’m 15 I live in ky I don't care if you believe me or not but I can't get sleep at night because every time I close my eyes I get an image more like a 2 second memory but there not mine I get them all the time when my friends family have seen me randomly flinch and jump was because of that but when I zone out I go into someone's memory or something that's going to happen to them in the future I can be zoned out for 3 seconds but for me it has been 10 20 minutes at times and I can just walk around I'm like a viewer sometimes and then sometimes more then anything I am in there eyes I see what they see but I have no control at all the detail is crazy Some of the items, like beds guns tvs doorknob, design of the home or place and it has never been presented to me in. The images are the first time I've seen these items the house place Each image also has a unique stamp on me I feel useless sometimes with what I see but more the last 3 months stuff I seen came and happened to me the same stuff I'm not dreaming because it happens when I'm up but also when I'm sleeping and when I had trouble falling asleep was because I heard voices calling my name. Most of my dreams took place in a apocalyptic future before this stuff started since I was 13 I just feel like I need to tell someone this because of the memorie I seen that's why I need to know if this is real or not it’s getting to me and if I'm going crazy if I try and stop it form happing it doesn't happen I can get memories that are days months in the future and I can also get memories that already happened I don't know what to do anymore i don't thank it's a mental illness because it's too vivid and stuff comes to me then happens 3 days later I also have bad feelings when I enter into certain spaces my room bath room car anyway I've heard footsteps in house are when I'm alone I can't discount every experience as a figment of my imagination because my mom has also had similar experiences with the footsteps and I have them follow me I needed to tell this but I don't thank I'm crazy because they keep coming true that's why I am how I am and why I have been so paranoid checking and counting every person I see because there's other people there I sense them, but don't see them I know this is a lot I'm sorry I sound crazy but it's the truth that's why I can't sleep well I can't find anything online about this stuff so I'm just confused and you probably won't believe me whoever is reading this but there’s just so much that can’t explain I also feel like I’m in a dream in a dream with no escape I never know what’s really and what’s not sometimes I feel like I’m in a coma, waiting to get up please help me readit. Ask questions and I’ll tell you the answer to it and be truthful.

1 Comment
18:53 UTC


If earth is a grain of sand, how big would the universe be?

Would it be like a grain of sand on earth as a size comparison? Or would it be like a grain of sand on Jupiter? On the Sun?

I’m having an internal crisis about how insignificant we are and the fact we are floating in a random part of nowhere with no answers about the beginning or end of everything. I want to feed that crisis.

15:26 UTC


Where does the sun go?

03:35 UTC


Have you heard about the Fractal Holographic Universe?

02:55 UTC


How Long will take some new theory to be proven as Legit? Saturn's Rings Scenerio.

How long will take some new theory to be proven as Legit? If you heard about Saturn's Rings, New theory said that Saturn did not Terminated his moons due to bypassing roche limit, But it was due to collosion of some Gas Giant Planet and Saturn, Similar Way How Moon Was Formed ten Hours later due to Armageddon between Earth and Theia as it was shown in Nasa Simulation. How Long will take Some new Theory to be Legit? Thanks For Answers

11:47 UTC


Is there a theory about the universe that everything is just a computer game ?

People tried to explain this universe with different explanation. God, quantum mechanics, matrix. Was there a theory about a computer game yet ?

17:36 UTC


Gravitational pull between universes?

Hello so as we know our universe is expanding and that makes me assume the same for other universes. But as we also know everything has a gravitational pull.

But my question would be. Is the universe emitting a gravitational pull to other universes?
Like how a black hole sucks in matter, could a universe pull another universe into itself to form a "larger" universe. Similar to two water droplets merging together.

Thanks for taking time out of your day to read my post :)

03:00 UTC


Observable Universe Logarithmic Map

15:25 UTC


103-Year-Old Doctor Reveals the Secrets of Life https://youtu.be/fIOMlJi_5So

13:49 UTC


I think I’m in the wrong universe.

Flipping through instagram today (3/7/24) I saw a post that Rikishi, the former wrestler, would be signing autographs at some upcoming event, problem is I’m pretty sure he died along time ago. I vividly remember it was before Eddie.

23:49 UTC


My Big Bang Explanation Theory

Whenever I think about the Big Bang Theory I always wonder what came before it and I'd like to know if it is at all possible for my explanation for what caused the Big Bang to be possible.

At the moment we don't know how blackholes die and what I am thinking is that a super-doopa-massive black hole over billions and potentially trillions of years engulfs every remaining star, planet, galaxy other blackholes and every single atom in the universe. After this has happened it begins to shrink and shrink and shrink.

This blackhole then shrinks to an absolute zero singular point, like how there is absolute zero, and with all the atoms and energy in the universe concentrated in such a small point maybe there is a rule in the universe that the only way a blackholes pull can be broken is with all the energy in the universe. And once this happens all the matter is released in another Big Bang.

Are there any faults that you can think with my thoughts here. I know that dark matter is a thing and causes the universe to expand but there can only be so much so there might be a cut-off point where the universe cant expand anymore idk what you think?

12:15 UTC


Om namah shivaya

ॐ नमः शिवाय

18:08 UTC


Does anybody think about this too?

When someone dies. And there body is burned, buried and goes into the ground and decomposes. That mass is gone. But the energy still lives in the universe. Remember E=MC2? Energy =Mass times the speed of light squared. It’s the law of conservation. Meaning mass cannot be created or destroyed. So that energy still exists somewhere in the universe. So the “gone but not forgotten” or “there still here” Does that really mean something?

05:25 UTC


If light doesn’t experience any time how do light waves stretch over time and turn from gamma to radio waves

03:27 UTC


Hi im 19 can anyone help with this question at all?

So im just trying to figure things out if god is real then who made god and then who made the thing before and so on? i totally dont get it who made the universe but then what made the thing before the universe what started time and what was there before and before that there had to be something that started it but then something must of happened before that and so on? like many people think the big bang theory, OKAY but what happened before the big bang and so on? like i don't get it it just doesn't make sense

12:09 UTC


Matter interchanged between universes - question

If the principle that matter cannot be created or destroyed holds true, how would the scenario where a universe either loses or gains matter—matter that was previously non-existent in it—be explained? This seems to imply a violation of the conservation law within that universe, as matter would seemingly disappear from one universe and appear in another. How does this align with the fundamental laws of physics?

11:55 UTC


Sending time capsules to space that returns and lands after 20 million years

Would it be possible? Like something that would teach the future people how much we’ve reached as a civilization. Our tech, medicine, agriculture, all human knowledge. Maybe even an A.I. that would wait and teach any intelligent beings that comes across it to replicate our tech. Idk maybe this post should be in the fiction genre. It just seems to me like it’s all such a waste if it’ll all just go to waste with a single press of a red button.

05:23 UTC


My Idea for the Shape of the Universe

Just watched some stuff about the shape and scale of the universe and thought I'd give what I think.

The big bang occurred at some unknowable point in some type of something, outside of somewhere. It expanded outward, in a spherical shape (as that would be the easiest thing to expand as given volume to surface area ratio). As it expanded, it left some of its "shell" or "surface" behind. Like some sort of cosmic balloon, and everything is the gas inside of it. Except that the gas is made from the rubber of the plastic itself.

I do believe that the universe has a finite amount of matter, but as the particles are being ripped from the shell, the shell is slowly getting smaller (despite being unknowingly massive). I think that the shell would simply dissipate, and it would be possible to exit into whatever matter-less void the universe spawned in, since I think that it is likely the universe spawned inside of nothing.

Some may ask "but how did the universe come from nothing?" And that's a valid question. My best answer is that (if I can recall correctly) particles and anti particles come into existence and kill one another all of the time inside of the universe. Who's to say that in some EXTREMELY unlikely event, inside an INFINITE void, that something the size of the universe may occur. We would only get to see it because we are in it.

This void I have described to contain the universe, and possibly many more, may have existed for waaaayyyy longer than our current universe.

I couldn't really describe everything that I wanted to in perfect detail as I imagine it, but I hope that the basic idea gets through.

22:54 UTC

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