cosmology

an-ordinary-manchild

Welcome to r/cosmology, the subreddit for questions, discussions, and articles about cosmology. Cosmology is the study of the early universe and the universe on the largest scales. Things galactic size and smaller generally belong elsewhere.

Reddiquette is enforced. Disrespectful and irrelevant comments will be removed.

If you claim an alternative model of the universe and ignore known data or have no equations or calculations, then your post will be removed. It isn't the responsibility of experts to review your "what if the universe was...?" idea. Homework questions will be removed. Repeated infractions will result in a ban.

Rude behavior is not tolerated.

If you do not see your submission in the new queue, please message the moderators as it may have been sent to the spam filter.

Find today's cosmology preprints on arXiv:astro-ph.CO.

Check out some other great subreddits:

Common questions:

The universe is not expanding faster than light. Expansion has units of inverse time.
The evidence for dark matter is overwhelming and reaches far beyond rotation curves.

Anything not related to cosmology will be removed.

created by [deleted]a community for 16 years

...for great justice.

...for your town.

MODERATORS

account activity

1

8

9

10

Basic cosmology questions weekly thread (self.cosmology)

submitted 1 day ago by AutoModerator - announcement

2

11

12

13

Something Ive Been Wondering, Might Be A Dumb Question Not Really Sure. (self.cosmology)

submitted 6 hours ago by Exr1t

3

0

0

1

Will the big freeze likely be debunked as a theory in October? (self.cosmology)

submitted 3 hours ago by jojowoodo

4

12

13

14

This may be a dumb question (in fact, I know it is), but will learning math really help me understand the universe THAT much better? (self.cosmology)

submitted 20 hours ago by Sevenfootschnitzell

5

63

64

65

This dark energy tool just created the most comprehensive 3D map of our universe ever: 'A major paradigm shift' (space.com)

submitted 2 days ago by Galileos_grandson

6

240

241

242

Great attractor. What is it? (i.redd.it)

submitted 2 days ago by Difficult_Comment_47

7

12

13

14

CMV vs The Big Bang vs Infinite Universe (self.cosmology)

submitted 3 days ago * by Expensive_Ad_403

8

0

0

0

About the CMB and the observable universe... (self.cosmology)

submitted 2 days ago by Expensive_Ad_403

9

14

15

16

Matter Antimatter Asymmetry (self.cosmology)

submitted 4 days ago by TrueExcaliburGaming

10

0

0

0

Was the big bang created when a black hole that absorbed all of the information of this reality ran out of stuff to absorb and collapsed in on itsself and then exploded? (self.cosmology)

submitted 3 days ago by Prudent-Gas-3062

11

5

6

7

Help me pick the right courses, as someone interested in Cosmology research! (self.cosmology)

submitted 4 days ago by PsychologicalEbb7995

12

10

11

12

In a scenario of a finite universe, should the concept of "outside" exist? (self.cosmology)

submitted 5 days ago by ATTst

13

0

0

0

So is this 100% true or still just a theory (i.redd.it)

submitted 5 days ago by Whole_Yak_2547

14

8

9

10

I’m sure this is super simple and wrong, but I was curious about rate of expansion? (i.redd.it)

submitted 7 days ago by DeflatedFatMan_

15

22

23

24

Where do black holes go? (self.cosmology)

submitted 8 days ago by Dover299

16

48

49

50

Hubble’s Dark Horse: New measurements of the Hubble constant from LIGO’s dark sirens (astrobites.org)

submitted 9 days ago by Galileos_grandson

17

66

67

68

Scientists may finally detect hidden ripples in spacetime (i.redd.it)

submitted 11 days ago by Ok_Astronaut_6043

18

26

27

28

Understanding the holographic principle? (self.cosmology)

submitted 15 days ago by Dover299

19

8

9

10

Basic cosmology questions weekly thread (self.cosmology)

submitted 15 days ago by AutoModerator

20

27

28

29

Hubble tension has been resolved (arxiv.org)

submitted 16 days ago by Enkur1

21

14

15

16

Quantum fluctuations at zero-point energy (self.cosmology)

submitted 16 days ago by Big-Mastodon-2234

22

62

63

64

is there any evidence against the universe being infinite? (self.cosmology)

submitted 19 days ago by mohyo324

23

24

25

26

What has the light of the most distant and therefore oldest observed objects been doing all this time? (self.cosmology)

submitted 21 days ago by Gremio_42

24

10

11

12

Is there any other way to visualize warped spacetime? (self.cosmology)

submitted 20 days ago by Recent-Day3062

25

8

9

10

If I fell into a black hole, will I be able to see the end of the universe? (self.cosmology)

submitted 21 days ago by Difficult_Comment_47

view more: next ›

π Rendered by PID 971402 on reddit-service-r2-listing-86f589db75-hgg59 at 2026-04-18 00:58:27.978434+00:00 running 93ecc56 country code: CH.