Earlier quoted context omitted.
It's called "mathemagick".
No, the universe is expanding. No magic required.
Infinite amount of dark mathemagic is required for faster than light expansion of nothing.
If the universe is 13.8B years old, how can we see 46B light years away? (2018)
61–70 of 133 posts
Re: If the universe is 13.8B years old, how can we see 46B light years away? (2018)
#62And... another author that doesn't get it or looks for a controversial, clickbaity title. The correct way to state it would be to say: "We are seing things that are currently 46B light years away but since they are so far away we see them as they were 13.8B years ago when they were much closer than they are now." I see absolutely nothing difficult about that statement unless you really need to create some piece of co…
It's a pop science article, and I'm sure the audience that's into pop science articles found it interesting and probably learned something. I'm not really sure what you expect.
Re: If the universe is 13.8B years old, how can we see 46B light years away? (2018)
#63And... another author that doesn't get it or looks for a controversial, clickbaity title. The correct way to state it would be to say: "We are seing things that are currently 46B light years away but since they are so far away we see them as they were 13.8B years ago when they were much closer than they are now." I see absolutely nothing difficult about that statement unless you really need to create some piece of co…
The way you state it pretty blatantly leaves the question of "if they're 46B light years away, then how is the universe not at least that old?".
This comment heavily reminds me of the mannerisms of professors that have the mentality of "I deeply understand this subject from years of past studies, so you should be able to understand it from my vague and half assed explanation alone".
Re: If the universe is 13.8B years old, how can we see 46B light years away? (2018)
#64Earlier quoted context omitted.
It's at lesst a little confusing how something went from 14B light years away to 46B light years away (seems to be a distance of 32B light years total travel) in 14B years.
Except the galaxies do not travel. Galaxies are more or less stationary, it's the space inbetween that expands. Think in terms of raisins in a dough or points on expanding baloon. Neither of them could be said to travel, yet they can be seen to become more and more far away.
No, space inbetween is stationary. It's galaxies that shrinks. Think of ice in water.
Re: If the universe is 13.8B years old, how can we see 46B light years away? (2018)
#65Earlier quoted context omitted.
It's at lesst a little confusing how something went from 14B light years away to 46B light years away (seems to be a distance of 32B light years total travel) in 14B years.
Except the galaxies do not travel. Galaxies are more or less stationary, it's the space inbetween that expands. Think in terms of raisins in a dough or points on expanding baloon. Neither of them could be said to travel, yet they can be seen to become more and more far away.
and yet you stated nothing about this factor in your original comment.
Re: If the universe is 13.8B years old, how can we see 46B light years away? (2018)
#66Earlier quoted context omitted.
It's at lesst a little confusing how something went from 14B light years away to 46B light years away (seems to be a distance of 32B light years total travel) in 14B years.
Except the galaxies do not travel. Galaxies are more or less stationary, it's the space inbetween that expands. Think in terms of raisins in a dough or points on expanding baloon. Neither of them could be said to travel, yet they can be seen to become more and more far away.
Technically, galaxies do travel:
> In physical cosmology, peculiar velocity refers to the components of a galaxy's velocity that deviate from the Hubble flow. ....
> Galaxies are not distributed evenly throughout observable space, but are typically found in groups or clusters, where they have a significant gravitational effect on each other. Velocity dispersions of galaxies arising from this gravitational attraction are usually in the hundreds of kilometers per second, but they can rise to over 1000 km/s in rich clusters.
-- https://en.wikipedia.org/wiki/Peculiar_velocity
Granted, 1000 km/s isn't even 1% of light speed, so clearly this motion couldn't contribute much to a distant object's recession.
Re: If the universe is 13.8B years old, how can we see 46B light years away? (2018)
#67I like the thought that, since the Universe is expanding, so is my brain.
> Once objects are formed and bound by gravity, they "drop out" of the expansion and do not subsequently expand under the influence of the cosmological metric...
https://en.m.wikipedia.org/wiki/Expansion_of_the_universe#To...
Re: If the universe is 13.8B years old, how can we see 46B light years away? (2018)
#68Simply put: We can see 46 Billion Light Years away now, b/c it wasn't that far away when it was created.
No, the object is now 46b light years away, but we can’t see what it looks like now at that distance. We see an image of it when it was much closer and younger.
Re: If the universe is 13.8B years old, how can we see 46B light years away? (2018)
#69My two cents worth: One is a measure of time. The other is a measure of distance. The two are unrelated.
Um, no. Distance and time are related by the speed of light, which travels 1 light year (distance) in 1 year (time).
If space wasn’t expanding, the distance to a stationary object (in light years) would be exactly equal to the travel time of light from it (in years).
Re: If the universe is 13.8B years old, how can we see 46B light years away? (2018)
#70And... another author that doesn't get it or looks for a controversial, clickbaity title. The correct way to state it would be to say: "We are seing things that are currently 46B light years away but since they are so far away we see them as they were 13.8B years ago when they were much closer than they are now." I see absolutely nothing difficult about that statement unless you really need to create some piece of co…
Your dismissal underestimates the qualifications and pedigree of an established and excellent populariser of "cool" scientific topics. Sure he goes for clickbaity articles now and then, but he's pretty good at them in my experience, and your summary is both incorrect (there is no "current" over that distance scale) and leaves all explanation out.
It’s about as wrong as looking out a window and claiming the earth is flat “because it’s easier to imagine.” Just as dangerous, too...