Anthony Barreiro wrote:
Okay, 42 billion years is incomprehensible in human terms, but all the earlier steps are comprehensible ... .
Anthony, you mean 42 billion years as in 42 billing light-years, don't you?
I once built a super-simple model of the inner solar system. I used cotton balls, 0.02 meters in diameter, for the Earth, Venus and Mars. I used yellow peas for Mercury and the Moon, and a round table-cloth, 2 meters in diameter, for the Sun. I then placed the "planets" at the appropriate distances from the Sun. The Earth was about 200 meters from the Sun.
I couldn't believe how tiny cotton ball Earth looked when it was placed 200 meters from table-cloth Sun! And I couldn't believe how vast the depth of those 200 meters looked in comparison.
I had "scaled down" the size of the inner solar system some 700,000,000 times. I was able to picture in my mind, more or less anyway, how big the Earth actually is. But when I tried to picture the actual, physical depth of those 200 X 700,000,000 meters in my mind, trying to sum it up by adding kilometer after kilometer until I got to 140,000,000,000 kilometers - okay, it should have been 150,000,000,000 kilometers instead, big deal - I found that I couldn't do it.
I'm sure that there are people out there who are much better at imagining the stark reality of 8 light-minutes in their minds. I'm sure there are those who can do it.
But if people tell me they can actually imagine a
light-day, 24 light-hours, I'm not sure I believe them any more.
And imagining - actually imagining the physical
reality of a light-year, I'm quite convinced it is humanly impossible.
So, Anthony, if you can actually
comprehend all the steps leading up to 42 billion light-years, then you are 42 billion light-years and 8 light-minutes ahead of me.
Me, I can juggle the figures a bit. I can easily understand the difference between 21 billion light-years and 42 billion light-years, for example. Sure I can do that sort of thing.
But to comprehend the actual reality behind those figures... I can find no word to explain how impossible that is to me. Impossible, impossibler, impossiblest, mega super duper gobsmackedly impossiblest. And then some.
And you know what? I like it.
![Wink :wink:](./images/smilies/icon_wink.gif)
The universe doesn't have to stop expanding as far as I'm concerned!
Ann