Creation vs. Evolution

  • Thread starter ledhed
  • 9,687 comments
  • 442,950 views
Because the expansion of the universe isn't constrained by the speed of light.

Parts of the universe are receding from us in excess of the speed of light.
Do we actually know this, or is it at least a common theory? Are there any links with info on this? I'm curious...
 
It's a strong concept, based on the idea that as the universe itself expands the metric of expansion varies (most evidence suggests that the expansion varies with relative distance from the point of observation), thereby the speed of expansion isn't restricted by known laws or theories (special relativity in this case, as Famine said - Einstein worked under the assumption of a static universe). Take a look at the Friedmann equations and Hubble's Law if you'd like to read some more information on the topic. My grasp of it is that of a semi-informed layman so I may not be explaining it exactly as it should be.
 
Because the expansion of the universe isn't constrained by the speed of light.

Parts of the universe are receding from us in excess of the speed of light. So the light emitted from them can never reach us. From their point of view, we're receding from them in excess of the speed of light and light emitted from us can never reach them.

The universe and the observable universe are not the same thing. Parts of the universe cannot ever be observed from our position - nor can we be observed from them.

If we can't see it, how do we know it exists?...
 
Just because we can't see it, doesn't mean it isn't there!
By reasoning and logical deduction. Direct observation is not always possible but the presence of an object is betrayed by other evidence (black holes for example). Much of the matter in the universe is dark (and I don't mean "Dark Matter", I mean normal matter that emits no light) but we know it's there because of what it obstructs... (i.e. a dark nebula)

web.jpg

The particle horizon means that there are things that we will never be able to see because they are too far away - and hence there are objects that we can see in the night sky that cannot see each other for the same reason... an object 10 billion light years away from us to our right cannot see an object 10 billion light years away from us to our left... since they are 20 billion light years apart, they cannot see each other since the universe is just 13.5 billion years old, hence it's not possible for the light to have reached one from the other yet (they lie beyond each other's particle horizon) They are subject to the same particle horizon as we are - limited by the speed of light and the age of the universe...

Luckily, the universe is 13.5 billion years old, and not 6000 years old. If that were the case, the particle horizon (defined by the speed of light) would ensure that we could only see some 12% of our own galaxy, let alone other galaxies...
 
I guess you have to wonder if its possible for us to travel faster than speed of light. If this was the case then we could technically head to a planet we thought existed, but once we got their it could be either in a different spot to what we saw or have ceased to exist. But we would have to travel many times the speed of light for a decent amount of time.
 
If we can't see it, how do we know it exists?...

To expand on TM's post, we know it's there, but we don't know what's in it.

The expansion of the Particle Horizon is limited by the speed of light, by definition - it's the horizon beyond which particles can't have reached us by now, and the movement of particles is limited by the speed of light. The expansion of the universe's Event Horizon is not limited by the speed of light.

That and the fact that the Earth is (by definition) the centre of the Observable Universe, but the cosmological principle prevents the Earth from being the centre of the Universe.
 
That's not the reason, no.

Search for "Hubble Deep Field" in the Rumble Strip. You'll see a photograph of what happens when you point a powerful, non-atmosphere-restricted telescope at a patch of sky that seems to have nothing in it and leave it there for two weeks, gathering light.
 
I'll make it easier and post it.



A very interesting video indeed.

As another example of things we cannot see but know of their presence. We know other stars have planets. We know this because the star 'wobbles' due to the gravitational pull of the objects orbiting them e.g planets. The planets themselves are too far away to been seen, only the star can be seen. The 'wobble' of the star occurs in our sun, but we can see the other planets in solar system.

clear things up a little?
 
And, before the inevitable point comes up:

Logical deduction and calculation of things we cannot see is NOT the same as believing that a God you cannot see must exist.
 

Parts of the universe are receding from us in excess of the speed of light.

Doesn't this in itself violate Relativity? I thought relativity dictated, among other things, that if you had two objects moving away from eachother, each moving at the speed of light from the starting reference, relative to eachother they would still appear to be parting at the speed of light, not twice the speed of light?
 
Doesn't this in itself violate Relativity? I thought relativity dictated, among other things, that if you had two objects moving away from eachother, each moving at the speed of light from the starting reference, relative to eachother they would still appear to be parting at the speed of light, not twice the speed of light?
I think it's because we're dealing with two types of reference frame - inertial and noninertial, and that the 'speed' of an object depends on which one you are talking about. The speed of light is constant regardless of your frame of reference, which explains why you'd observe what you've just mentioned. A physical object like a distant galaxy can appear to be moving 'faster' than the speed of light, but only by virtue of the fact that it is moving inside a noninertial frame of reference relative to us - i.e. it is moving away from us in an expanding universe. It's a bit of an optical illusion, though... we know from Hubble's Law that the more distant a galaxy is, the faster it appears to be moving - even to the point where the most distant objects are calculated to be traveling at a 'speed' higher than c. But this doesn't contradict relativity, since the objects are not moving faster than light in their own region/inertial frame of reference... The fact that they appear to us to be moving with velocities greater than c is because partly due to our distance from them and partly because the universe is expanding (and accelerating), but not because these objects are themselves moving "faster" than c.
 
Wow this is some interest stuff here and as Alfaholic said, it makes your brain hurt. Thanks for the info guys 👍! Isn't science wonderful :D?
 
Not sure if that's exactly right - or even that well worded - I must have edited it 20 times, and have just changed it a bit again... suffice it to say that it is an easily demonstrable effect and involves no magic or supernatural mumbo-jumbo to explain it...

What is pretty lucky, however, is that we can see these things at all. Imagine for a moment that the Earth had several suns and that it was perpetual daylight everywhere on Earth, all of the time... I remember clearly the day that I saw the planet Venus one morning and realised that the only reason we don't see stars 24/7 is because of the presence of the Sun. We're lucky in a way that stars and galaxies are visible to us at all, otherwise our perceptions of where we are in the universe might be very different...
 
Not sure if that's exactly right - or even that well worded - I must have edited it 20 times, and have just changed it a bit again... suffice it to say that it is an easily demonstrable effect and involves no magic or supernatural mumbo-jumbo to explain it...

What is pretty lucky, however, is that we can see these things at all. Imagine for a moment that the Earth had several suns and that it was perpetual daylight everywhere on Earth, all of the time... I remember clearly the day that I saw the planet Venus one morning and realised that the only reason we don't see stars 24/7 is because of the presence of the Sun. We're lucky in a way that stars and galaxies are visible to us at all, otherwise our perceptions of where we are in the universe might be very different...

Have you read Asimov's "Nightfall" story? Describes a hypothetical world with exactly that situation, sky gets dark once in a millenium or so. There is no science of astronomy, then Bang!!!!! Mysterious points in a sky strangely gone black. What happens to civilization?
 
but it's all based on assumptions - that parts of the universe are expanding faster than light, that the parts expanding at that speed never stop expanding faster than light, that nothing travels faster than light, or ever will, it's quite a few assumptions
 
but it's all based on assumptions - that parts of the universe are expanding faster than light, that the parts expanding at that speed never stop expanding faster than light, that nothing travels faster than light, or ever will, it's quite a few assumptions


[Inigo]I do not think that word means what you think it means.[/Inigo]
 
but it's all based on assumptions - that parts of the universe are expanding faster than light, that the parts expanding at that speed never stop expanding faster than light, that nothing travels faster than light, or ever will, it's quite a few assumptions

No. It's all based on measurements, observations and calculations.
 
but it's all based on assumptions - that parts of the universe are expanding faster than light, that the parts expanding at that speed never stop expanding faster than light, that nothing travels faster than light, or ever will, it's quite a few assumptions

The world is 6000 years old, and you say science makes assumptions?

Nobody assumed that the universal speed limit is the speed of light. That is an observation, a calculation, that results from the math put forth by some pretty smart guys.

Nobody assumed that there's an event horizon beyond which we cannot see, but the fact that everything is getting farther away from everything (an observation, not an assumption) and the fact that further objects recede faster (same parenthetical note) forces us to think that there must be something so far away and so fast we will NEVER be able to observe it directly. But expansion of the universe itself is not quite the same thing as moving through it, which is where the light limit breaks.

Calling them assumptions is getting it backwards. Nobody assumed that the speed of light was the limit and then based Physics around that. They looked at Physics and discovered that the speed of light is (apparently) the limit.
 
Who said the earth is 6,000 years old? Where does it say in the Bible that the earth is only 6,000 years old? This is adopted by 'Young Earth Creationist' that take the Bible very literally. This has also been discussed at length in this thread, in Peter 3:8 the Bible says that a day to God is LIKE a thousand years. Pretty ambiguous. Just curious who takes the Young Earth idea seriously? And if so, what of the undeniable scientific evidence that we have that supports a much, much, older earth?
 
The speed of light is the limit, as we know it. Till anyone proves otherwise that is the limit.

Well... to a point, certainly.

The speed of light in a vacuum (c) is the maximum speed of any particle travelling through normal space-time. That's why the particle horizon (the maximum limit from which any particle travelling through the universe could have reached us) and the event horizon of the universe are different.
 
Who said the earth is 6,000 years old? Where does it say in the Bible that the earth is only 6,000 years old? This is adopted by 'Young Earth Creationist' that take the Bible very literally. This has also been discussed at length in this thread, in Peter 3:8 the Bible says that a day to God is LIKE a thousand years. Pretty ambiguous. Just curious who takes the Young Earth idea seriously?

But God doesn't say it took 7 days to create anything. The bible says that God did it in 7 days - which is different. If I remember correctly, Genesis doesn't contain direct quotes.

"In the beginning God created the heaven and the earth. "

That's not God talking. So when it says:

"And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day."

That's not God's interpretation of a day, that's the speaker's interpretation of a day - as it was written in Hebrew at the time of the original writing of the OT. The Hebrew word was then translated as best as possible from Hebrew into English, and the translator decided that the term "day" was most appropriate. Not "a thousand years" or "a day as God perceives it", but simply the English term "day".

So I think it should be interpreted quite literally.

Pako
And if so, what of the undeniable scientific evidence that we have that supports a much, much, older earth?

What of the undeniable scientific evidence that supports evolution?
 
I see what you're saying, but then if you get into the 'writings inspired by God' idea that these writings in the Bible that are given to us from visions can be indirectly used as quotes from God. After all it is God's word. So then I go back to 'a thousand years is LIKE a day to God' verse. It's fun to talk about but not required to accept God's salvation, if you're into that kind of thing.
 
I see what you're saying, but then if you get into the 'writings inspired by God' idea that these writings in the Bible that are given to us from visions can be indirectly used as quotes from God. After all it is God's word. So then I go back to 'a thousand years is LIKE a day to God' verse. It's fun to talk about but not required to accept God's salvation, if you're into that kind of thing.


Just so I can get it straight. What you're telling me is that Genesis is a "vision", and that the "seer" of this "vision" experienced God's notion of time. And so the seer saw the creation of the world as a day. But since the seer was experiencing God's point of view, we are to interpret the seer's experience with the understanding that to him, a thousand years would have been like a day.

If that's accurate, I've got a few questions:
Who is the seer?
How can you trust his vision?
How can the flawed mind of a mortal experience time the way God does?
 
Back