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Comment by goodside | Hacker News Reader

As pointed out by others, the largest scales on this animation are completely wrong. The figure given for the Observable Universe, 14 billion light years, is actually only half of the distance between us and the HUDF.YD3 galaxy. The figure given for the total size of the Universe is actually the estimated size of the Observable Universe: 93 billion light years. The size of the Universe itself is not known with any certainty.

If you're wondering to yourself how anything can be further away than (age of Universe) * (speed of light), read up on comoving distance and the metric expansion of spacetime. I wrote a fairly lengthy series of comments on this six months ago: http://news.ycombinator.com/item?id=1317907

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One point of note is that distances beyond 100M ly are difficult to measure and prone to large errors. Beyond 1Bn ly there is nothing but the Hubble Law. It could be that objects observed to have a large redshift (and hence appearing far away by the Hubble Law) are in fact nearby objects.

I'm wondering what you think about Wun-Yi Shu Universe (http://byrev.org/tech/wun-yi-shu-universe/). I saw a post about his paper here on HN a while ago.

Without looking too hard at it, this seems to be nonsense. Shu pulls parameters out of the air all over the place and makes wild philosophical claims about the nature of time without explanation. He selectively ignores basic physics, and makes up nonstandard formulas for various quantities whenever they're needed.

Further, he repeatedly draws conclusions that, if proven, would win him a Nobel Prize. The biggest is that black holes can't exist. Others include having solved both the flatness problem and the horizon problem and ruling out the only known explanation of the CMBR without replacing it with anything else.

But, rather than take my word for it, you should just apply the Baez Index: http://math.ucr.edu/home/baez/crackpot.html

It could be wrong, but it gets across the point. The scrollbar would still be the same width, the rate of change of scale would be a little higher (in visual perception)

I spent probably half an hour reading those comments. Good stuff. Do you have a background in cosmology?

No, none. I never went past General Relativity in school but I read a few textbooks on my own. Don't take anything I say with authority.

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