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Yet you can't account for them now being 46B light years away without breaching C, or encompassing the expansion of the universe, within which things are moving

Yet you can't account for them now being 46B light years away without breaching C, or encompassing the expansion of the universe, within which things are moving. I think he manages a clear explanation of that without scaring away too many. Your "correct" version on the other hand, leaves more questions than answers, not least of which being how do we ever get 46B ly distance in something 13.8B years old. Then you have to cover the expansion, relativity, and hey presto you've written the article. Just skimming the other comments here makes it clear it's not a topic that's well understood or intuitive. Clickbait it ain't, and the title is a very fair question. I'm really disappointed to see this the top voted HN answer right now...

rotrux 7y ago
Right - It is not clear how we can see something more than 13.8B ly away since it would take more than 13.8B years for signals of its existence to reach us. From our frame of reference, that would mean the emission started before the big bang.
lmilcin 7y ago
This was described almost hundred years ago. https://en.wikipedia.org/wiki/Hubble%27s_law https://en.wikipedia.org/wiki/Hubble%27s_law "(...) the notion of the universe expanding at a calculable rate was first derived from the general relativity equations in 1922 by Alexander Friedmann" The space expands. It's been known for a long time. We might not know why exactly this happens and there is still some discussion about ultimate fate of the universe although prevalent theory is that it will expand at an ever faster rate until every molecule will be torn from each other and matter will no longer be able to form.
- saagarjha 7y ago
  Great, now you’ve started to touch on the points mentioned in the article.
- NeedMoreTea 7y ago
  Sure, but the high school, pop science and TV explanations of relativity and the universe rarely consider anything apart from the two trains travelling toward each other, nearing C, with an observer aboard one train. People can grasp that relatively easily, along with doppler explanations of red shift. Every decent attempt to take a step or two further is to be approved. :) When tracks start moving as well it gets mind bending, and no longer intuitive. Now we have multiple scenarios where the combination of track movement (universe expansion), and train movement result in it being "obvious" you have to exceed C somewhere, which we're told is impossible. Otherwise how can the distances end up where they are. It's between these two points most non-physicists stop as it starts to feel deeply contradictory.

rotrux 7y ago

Right - It is not clear how we can see something more than 13.8B ly away since it would take more than 13.8B years for signals of its existence to reach us. From our frame of reference, that would mean the emission started before the big bang.

lmilcin 7y ago

This was described almost hundred years ago. https://en.wikipedia.org/wiki/Hubble%27s_law https://en.wikipedia.org/wiki/Hubble%27s_law "(...) the notion of the universe expanding at a calculable rate was first derived from the general relativity equations in 1922 by Alexander Friedmann" The space expands. It's been known for a long time. We might not know why exactly this happens and there is still some discussion about ultimate fate of the universe although prevalent theory is that it will expand at an ever faster rate until every molecule will be torn from each other and matter will no longer be able to form.

saagarjha 7y ago
Great, now you’ve started to touch on the points mentioned in the article.
NeedMoreTea 7y ago
Sure, but the high school, pop science and TV explanations of relativity and the universe rarely consider anything apart from the two trains travelling toward each other, nearing C, with an observer aboard one train. People can grasp that relatively easily, along with doppler explanations of red shift. Every decent attempt to take a step or two further is to be approved. :) When tracks start moving as well it gets mind bending, and no longer intuitive. Now we have multiple scenarios where the combination of track movement (universe expansion), and train movement result in it being "obvious" you have to exceed C somewhere, which we're told is impossible. Otherwise how can the distances end up where they are. It's between these two points most non-physicists stop as it starts to feel deeply contradictory.