Are there any analogies that are actually meaninful?

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Discussion Overview

The discussion revolves around the challenges of finding meaningful analogies to describe the vastness of the universe and other large-scale concepts in physics. Participants explore the limitations of human perception and the effectiveness of various analogies, particularly in relation to size and distance, including the speed of light and the scale of the Milky Way.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • Some participants express skepticism about the ability to find analogies that accurately convey the size of the universe compared to Earth, noting that existing comparisons often fail to be meaningful.
  • One participant suggests that the size of Earth relative to the universe is akin to 1/180th the width of a hydrogen atom compared to Earth, but questions the visualizability of such a comparison.
  • Several participants share links to scale visualization tools, indicating a preference for visual representations over written analogies.
  • Another participant highlights the extreme difference in magnitude between the Earth and the observable universe, emphasizing that human sensory experience is limited to a few orders of magnitude.
  • One participant critiques the use of analogies in geology, arguing that they often lead to misunderstandings and do not effectively convey the true scale of phenomena.
  • There is a suggestion that creating analogies within a limited scale (e.g., 10,000 or less) may be more effective for comprehension.

Areas of Agreement / Disagreement

Participants generally agree on the difficulty of finding meaningful analogies for vast concepts, but multiple competing views remain regarding the effectiveness of existing analogies and the potential for creating new ones. The discussion remains unresolved on what constitutes a truly meaningful analogy.

Contextual Notes

Participants note the limitations of human perception and the challenges posed by extreme differences in scale, which may affect the effectiveness of analogies. There are also concerns about the reliability of certain online resources shared in the discussion.

MathJakob
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Obviously most humans understand that the universe is incredibly large, so large that we can't even find an analogy that we can relate to. The problem is no two things we can visualize and comprehend can describe the relation of the size of Earth to the universe.

The closest one I found and I don't know if it's accurate but it was that 'The size of Earth compared to the size of the universe is the same as 1/180th the width of a hydroden atom compared to Earth

This still isn't meaninful as I don't think it's possible to visualize that.

Does anyone know any accurate analogies for things like the speed of light, the size of the universe, or even the milkyway, relative distances ect?
 
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Yeh I've seen those scale apps before and they're pretty cool. My favorite is http://scaleofuniverse.com/cgi-sys/suspendedpage.cgi

I was after written analogies though.
 
MathJakob said:
Yeh I've seen those scale apps before and they're pretty cool. My favorite is http://scaleofuniverse.com/cgi-sys/suspendedpage.cgi

I was after written analogies though.

That URL you provided is considered a high-risk website for virus infection you should find an alternte or disable it in your post. You might want to run a scan of your machine as well.

EDIT: Sophos Web Protection flagged the site:
Code:
High Risk Website Blocked

    Location: searchresultsguide.com
    Access has been blocked as the threat Mal/HTMLGen-A has been found on this website.
    Return to the page you were previously viewing.
 
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jedishrfu said:
That URL you provided is considered a high-risk website for virus infection you should find an alternte or disable it in your post. You might want to run a scan of your machine as well.

Really? I've used the site many times before and it's been fine. That is strange... use this site then http://htwins.net/scale2/
 
MathJakob said:
Really? I've used the site many times before and it's been fine. That is strange... use this site then http://htwins.net/scale2/

Thanks, I had posted that one in my earlier post but at least now I know you saw it.

I don't think you'll find an analogy of the universe's size to something on Earth since we don't know how big it is.

Hey maybe you could develop your own analogies and post them here. I think people respond well to analogies that limit the scale to within 100, 1000, or maybe 10,000. Any higher and it can't be easily imagined so you could use that range of 10,000 or less as a baseline.
 
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The problem with finding an analogy suitable for visualization is fundamentally a problem of extremes of magnitude. The diameter of the Earth is around 13,000 km. The diameter of the observable universe is on the order of 10^24 km. So you've got some 20 orders of magnitude difference between these two things. Humankind's sense of scale is informed by experience, which is limited by the human sensory system. What's the biggest thing you can reliably visualize, and what's the smallest? I think you'll find these things are at most a handful of orders of magnitude different, not 20.
 
OP that's a great question.

In geology we often use analogy and it usually has little value. In fact it often provides a false understandings of time, size, quantity, etc.

'There are as many stars as there are grains of sand in the ocean'. No there isn't. Add or subtract a couple of zeros to the numbers of grains of sand and it would mean zilch to any of us. Nobody has a clue as to the number. We can't even fathom the amount of grains in bucket. We use mathematics. Usually the math is logical and expresses a number that is rational in describing some phenomenon. Being logical doesn't mean we relate to it.

I went to a lecture a couple decades a go and a prof purposely left a zero off of a large number. He mentioned it at the end of the lecture stating that the Universe has been reduced to a tenth of its size but nobody noticed. A tenth or a billionth it's size mean nothing to our limited physical senses and experience in the real world around us.
 

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