What percentage of the universe do we know

Click For Summary
SUMMARY

The discussion centers on the impossibility of quantifying the percentage of the universe that humanity knows. Participants argue that if the universe is infinite, then defining 100% becomes meaningless, as infinity cannot be treated as a single value. The conversation highlights that the observable universe is finite, but the unobservable universe remains unknown, rendering any percentage calculation undefined. Ultimately, the consensus is that discussing the percentage of knowledge about an infinite universe is futile.

PREREQUISITES
  • Understanding of basic concepts in cosmology, including the observable and unobservable universe.
  • Familiarity with mathematical concepts related to infinity and limits.
  • Knowledge of the philosophical implications of knowledge and observation in science.
  • Basic understanding of scientific inquiry and the nature of unknown quantities.
NEXT STEPS
  • Research the concept of the observable universe versus the unobservable universe in cosmology.
  • Study mathematical theories related to infinity and how they apply to physical quantities.
  • Explore philosophical discussions on the limits of human knowledge in the context of the universe.
  • Investigate current scientific theories about the size and structure of the universe.
USEFUL FOR

Students of physics, cosmologists, philosophers of science, and anyone interested in the limits of human knowledge regarding the universe.

Radu Mitroi
Messages
1
Reaction score
0
Hello.
First of all, I must say that I'm new to this forum, so I apologize if I'm posting in the wrong section.
I'm a 17 year old with not that much knowledge about physics, so if what I'm talking about makes no sense or is completely stupid, just let me know.

A couple of days ago I asked myself: Is it possible to say what percentage of the universe do we know? (note: I'm talking about the whole universe, not just our observable universe)
At first I said that it is not possible to answer such question since it implies that we know what 100% of the universe is. If the universe is, indeed, infinite, that means we can do some math, as 100% = infinite.
https://scontent-frt3-1.xx.fbcdn.net/v/t34.0-12/14642996_1165564973536187_187242484_n.png?oh=18cc2d1f2867750971fa0dff9a00899c&oe=57FC053B
No matter what value we give to X, the answer will be the same, that is infinite. With this in mind, does it mean that what we currently know about the universe represents an infinite amount? And if so, it means that, as X increases, the result will still be infinite. That means that no matter how much we progress, how much more we learn about the universe, we will still know as much as we currently know... which doesn't really make sense, since we obviously increased the amount of information we have about it.
 
Space news on Phys.org
Why not start with a simpler question: What percentage of your left big toe do you know?
 
We can't know anything scientific about what can't observe.
 
  • Like
Likes   Reactions: jim mcnamara
Radu Mitroi said:
A couple of days ago I asked myself: Is it possible to say what percentage of the universe do we know? (note: I'm talking about the whole universe, not just our observable universe)

It is not possible, as we don't know the size of the entire universe.

Radu Mitroi said:
At first I said that it is not possible to answer such question since it implies that we know what 100% of the universe is. If the universe is, indeed, infinite, that means we can do some math, as 100% = infinite.

I don't think your math is valid. As far as I understand, infinity represents an ever increasing quantity, not a single value. You cannot say 100% equals infinity since there are a never-ending number of values for infinity. You also couldn't say 100% equals 2 and 4.
 
You could pose the question as x+y =1, where x is the observable universe, y is the unobservable universe and 1 is the sum.. Given 'y' is always unknown, the question is undefined.
 
  • Like
Likes   Reactions: Stephanus
Radu Mitroi said:
If the universe is, indeed, infinite, that means we can do some math, as 100% = infinite.
The math you can do is simply
##x/\infty=0##, wherby ##x## ist finite.

Therefore you can't talk about a percentage of the infinite universe depending on the size of the observable universe.
 
Last edited:
On the other hand, the universe might not be infinite, nobody knows.
However it still remains pointless to discuss percentage of an unknown quantity.
 
  • Like
Likes   Reactions: jim mcnamara and jbriggs444

Similar threads

  • · Replies 20 ·
Replies
20
Views
2K
  • · Replies 38 ·
2
Replies
38
Views
6K
  • · Replies 33 ·
2
Replies
33
Views
6K
  • · Replies 5 ·
Replies
5
Views
2K
Replies
18
Views
1K
  • · Replies 11 ·
Replies
11
Views
3K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 8 ·
Replies
8
Views
5K
  • · Replies 29 ·
Replies
29
Views
3K
  • · Replies 18 ·
Replies
18
Views
2K