Well, before I start, I understand Hubble's law and the data it's based on. You look at a type Ia supernova, the farther away it is, the more red-shifted it is. So the universe is not only expanding, it's accelerating.
I get that, no need to link me to Hubble's Law on wikipedia.
But here's what I don't get:
Actually the farther away something is, the older the image we're getting. So if you're looking at a galaxy 1 billion light years away, you're looking at it 1 billion years ago.
So far that should not be controversial. In fact, all astronomers know it. They even say it every time they discover some galaxy from billions of years ago.
Here's where I go off my meds though: doesn't it mean that you could look at Hubble's law as a function of TIME and red-shift instead of SPACE and red-shift? So basically, the farther back in time we observe something, the faster it was going, and the closer to the present we look, the slower things move.
That looks to me more like the image of a universe that exploded at near the speed of light, way back in ye olde Big Bang, and it's been slowing (e.g., due to gravity) ever since.
Which is where I stop and think I might have gotten something about it wrong or I'm missing something. Any smarter folks can explain to me how the conclusion that it's accelerating takes it all into account?
I get that, no need to link me to Hubble's Law on wikipedia.
But here's what I don't get:
Actually the farther away something is, the older the image we're getting. So if you're looking at a galaxy 1 billion light years away, you're looking at it 1 billion years ago.
So far that should not be controversial. In fact, all astronomers know it. They even say it every time they discover some galaxy from billions of years ago.
Here's where I go off my meds though: doesn't it mean that you could look at Hubble's law as a function of TIME and red-shift instead of SPACE and red-shift? So basically, the farther back in time we observe something, the faster it was going, and the closer to the present we look, the slower things move.
That looks to me more like the image of a universe that exploded at near the speed of light, way back in ye olde Big Bang, and it's been slowing (e.g., due to gravity) ever since.
Which is where I stop and think I might have gotten something about it wrong or I'm missing something. Any smarter folks can explain to me how the conclusion that it's accelerating takes it all into account?
via International Skeptics Forum http://ift.tt/2xrF7Cu
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