What percentage of the universe do we know

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Discussion Overview

The discussion revolves around the question of what percentage of the universe we know, specifically considering the entire universe rather than just the observable part. Participants explore the implications of infinity and the challenges of quantifying knowledge about an unknown or potentially infinite universe.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions whether it is possible to determine what percentage of the universe we know, suggesting that the concept of 100% implies a complete understanding of the universe, which may not be feasible if the universe is infinite.
  • Another participant humorously suggests starting with a simpler question about personal knowledge, indicating a skepticism about the original question's validity.
  • A participant asserts that scientific knowledge is limited to what can be observed, implying that unobservable aspects of the universe cannot be quantified.
  • One participant argues that the question is undefined because the size of the entire universe is unknown, and thus any attempt to quantify knowledge about it is problematic.
  • Another participant challenges the mathematical reasoning presented by the original poster, stating that infinity is not a single value and cannot be equated to 100%.
  • A different perspective is offered, proposing a mathematical representation where the observable universe and unobservable universe sum to one, but emphasizes that the unobservable part remains unknown.
  • One participant reiterates that if the universe is infinite, discussing percentages becomes meaningless, as any finite knowledge would approach zero in relation to infinity.
  • Another participant introduces the idea that the universe might not be infinite, but still finds the discussion of percentages regarding an unknown quantity to be pointless.

Areas of Agreement / Disagreement

Participants express disagreement on the validity of quantifying knowledge about the universe, with some arguing that it is impossible due to the unknown nature of the universe, while others challenge the mathematical interpretations of infinity. No consensus is reached regarding the feasibility of the original question.

Contextual Notes

Limitations include the dependence on definitions of the universe and infinity, as well as unresolved mathematical interpretations regarding the relationship between observable and unobservable quantities.

Radu Mitroi
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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.
 
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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.
 
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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.
 
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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.
 
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