|
Simpo Two
54,274 posts
134 months
|
Mr Gearchange said: Everything was created 4000 years ago by the Lord. One the first day he created the heaven and the earth If he'd created a pub as well he could have had lunch in it. 'What do you mean, you only have bread and fish? Oh alright, a fish sandwich then please'
|
|
|
Gene Vincent
4,002 posts
27 months
|
If I may, I'd like to address the matters discussed above my last post.
It is matter of the speed of light.
It is a constant and is not violated.
To explain the apparent increase in the speed of far distant groups of galaxies, we need to take the analogy of the balloon a little further.
First, there are distinct bands of red shifted speed of expansion, there are 5 of them.
So, we must think of 6 balloons, each inside the other like Russian dolls.
In the space between each balloon there are Galaxies and each galaxy is expanding within the laws we know here, so the whole structure of the 6 balloons is expanding as a result of the expansion of the little 'balloon' of each galaxy in that layer, light has to pass from the most distant to our detectors.
By way of explanation, the little balloons representing the galaxies are not representative of the mass of the galaxies themselves but their effect in space by din't of the interaction of the fundamental forces.
So although the galaxy itself is expanding at close to the speed of light the effect at the edge of their influence is less.
The combined effect of this 'cellular' expansion within the balloons is to give the impression of things moving at faster than light speed.
The other interesting thing about the distinct bands is that (if I've read Penroses recent paper correctly) is that they could be vestiges of previous BBs.
Now... reading Penrose is fraught with pitfalls and I may have over simplified his principle idea and the paper is quite new and I was not in on it, so I start from just his much earlier vestigial original on this.
|
|
|
Eric Mc
67,261 posts
134 months
|
I went to school with a Benny Penrose.
|
|
|
stew-S160
6,065 posts
107 months
|
I was looking for this earlier, took a while to find. Imagine we are the dot marked with the X(We are still moving, not stationary), expansion happens to all points of spacetime. (Only need to look at C and D) 
|
|
|
Super Slo Mo
2,234 posts
67 months
|
I don't think that helps particularly. Like most analogies, it appears overly simplistic, and isn't really helping to describe what's going on, it's similar to the 'raisins in a cake' analogy that I keep seeing on the web.
|
Advertisement
|
|
|
TimJMS
2,045 posts
120 months
|
Throughout human history, we have always had to modify our universe view. In Copernicus' time, and for aeons before, the Earth was the centre of an unchanging Universe. 50 years ago Steady State Theory was the accepted norm. Then came Big Bang, but as we became better at measuring things the inflationary model of Big Bang theory was dreamt up to plug the void so to speak. As I said earlier it's all a bit "make - it - up - as - you - go - along" theory. Until something simple, pure and truly elegant comes along, I remain sceptical. There'll be something else along next week 
|
|
|
budgie smuggler
796 posts
28 months
|
ewenm said: 2 things here. Firstly, there was no visible light at the big bang, that comes later as it is generated by fusion reactions in stars so the first generations stars need time to form, so any expansion prior to that won't be "recorded" by light. Secondly, thinking of "expansion" or "inflation" in terms of "stuff moving apart against a static background" is flawed. You need to think of the background and the stuff expanding/inflating (the dots on a balloon analogy). That said, the "inflationary period" is a theory that fits the observed evidence but it still feels like a fudge to me. Of course, a lot of advanced physics is counter-intuitive and yet demonstrably accurate so a theory "feeling like a fudge" isn't a valid reason to reject it.  You're assuming there was no black body radiation at the big bang? I thought that was near enough settled as the source of the cmb. I.e. due to expansion of the universe this black body light is now redshifted to the point where it is in the microwave part of the spectrum (and that one way we can estimate the size of the universe).
|
|
|
ewenm
24,467 posts
114 months
|
Would that have been visible light?
Edit: Anyway, Gene V has explained it far better, and helped claify my understanding of it.
|
|
|
hornet
5,472 posts
119 months
|
ewenm said: Would that have been visible light?
Edit: Anyway, Gene V has explained it far better, and helped claify my understanding of it.
My understanding was the photons in the early universe were "trapped" in a sort of high energy "soup" and were only released once things had cooled to a certain point, allowing them to break free? Sort of similar to the how the light we see from the Sun is made of photons that have spent thousands of years migrating to its surface?
|
|
|
mattnunn
4,114 posts
30 months
|
 Basically God had an idea, then he thought about it for a bit, then when he had all the constants and mathematics sorted it sprung into being
|
|
|
hornet
5,472 posts
119 months
|
mattnunn said: Basically God had an idea, then he thought about it for a bit, then when he had all the constants and mathematics sorted it sprung into being Genuine curiosity here. Is time as we understand it purely a function of "our" universe, or does it somehow already exist? The reason I ask is that the notion that God "had an idea and thought about it for a bit" implies passage of time, as you have cause (having the idea) and effect (putting it in action). The idea exists in a timeframe, therefore so does God. That being the case, there must also be laws determining God, in which case where did they come from? Would seem to get to "Turtles all the way down" very rapidly. If there aren't any laws determining God, how could whatever you wish to define as God design and mediate the laws of our universe?
|
|
|
Gene Vincent
4,002 posts
27 months
|
hornet said: mattnunn said: Basically God had an idea, then he thought about it for a bit, then when he had all the constants and mathematics sorted it sprung into being Genuine curiosity here. Is time as we understand it purely a function of "our" universe, or does it somehow already exist? The reason I ask is that the notion that God "had an idea and thought about it for a bit" implies passage of time, as you have cause (having the idea) and effect (putting it in action). The idea exists in a timeframe, therefore so does God. That being the case, there must also be laws determining God, in which case where did they come from? Would seem to get to "Turtles all the way down" very rapidly. If there aren't any laws determining God, how could whatever you wish to define as God design and mediate the laws of our universe? Metred time as we know it has existed for only as long we have known how to metre it. However time as a procession of causality has existed since the first thing 'moved', time is a result of motion or movement and that pre-dates us hugely. There is only our Cosmos, we can speculate that there are others but that is all it is, speculation. Plus, for a photon there is no time at all, there is simply space and that is compressed to an instant also, its life, its journey, its entirety is compacted to an instant. The light form the edge of the Cosmos may have travelled 13.7 billion years to get here as far as we are concerned, but for the photon its just an instant, and the journey that for us is a time beyond literal comprehension in its longevity, is for the photon an equally incomprehensibly small instant in time. Time is fluid and relativistic, it is not static, it is not a 'thing' as such, time could more easily be seen as a consequence, not an item. There is no God, there is just existence and we can see that to a photon that is so short as to be very nearly non-existence! The Cosmos is too wondrous to be dismissed by the moronic 'God did it', that is such a corruption of the true beauty in the complexity and nuance of existence that it's an impoverished viewpoint. In short if you think having a God to make all this is awesome, then the reality is going to totally f  k your brains out... God comes a very poor second to reality. http://209.160.41.193/Images/Avatars/240.gif
|
|
|
AJI
2,018 posts
86 months
|
I think I've asked similar question as the OP on the internet before too.
I can understand that with expansion/inflation being faster than the speed of light that we can now look back at the original EM wave emissions not long after the big bang.... but why are we told that light speed in not surpassable?
If it takes an infinite amount of energy to accelerate anything with mass to light speed then I take it this was not the case during the early periods of the universe.
But the thing I still can't get my head around is that when they say with more and more powerful telescopes they can see further and further back in time and can see closer and closer to the big bang origin.....does this mean with a powerful enough telescope yet to be developed that they could in theory see back to the singularity itself (or read that to be the very first EM wave transmission after the big bang) ???
|
|
|
Blib
Original Poster
20,666 posts
66 months
|
AJI said: But the thing I still can't get my head around is that when they say with more and more powerful telescopes they can see further and further back in time and can see closer and closer to the big bang origin.....does this mean with a powerful enough telescope yet to be developed that they could in theory see back to the singularity itself (or read that to be the very first EM wave transmission after the big bang) ??? That's part of my issue with all of this.
|
|
|
Gene Vincent
4,002 posts
27 months
|
Back from the Pub quiz... 8th win in a row... murmurrings of discontent.
The more powerful the telescope just adds to the 13.7 billion years... so if we make a super-duper hyper-vision one a century from now it might see 20 billion years and the age increases at the 'front end' of the 'ageing' maths.
So if the inflationary period is unchanged we just add 6.3 billion years to the 50billion.
This is very likely to happen.
Apart from Cosmic Background Detectors no telescope along the lines of a Hubble can look back into the inflationary period.
This is done with pure maths, we can work out what happened in that time by colliding toys like CERNs accelerator, when we smash things at huge velocities with added energies we create some of the conditions that were in the inflationary period, not exactly, but close enough for us to have a 5sigma confidence level as to their accuracy.
We will learn more and although a Hubble can't look in that temporal direction it can see star formation and supernovae in the larger Cosmos now, this also gives us clues as to what exactly happened in the inflationary period, it is nowhere near as cut and dried as the info from CERN but it does often provide a place to start.
The variable in the inflationary period is not likely to be refined for a while yet, we have issues with the maths, most especially in the resolution of the split point and effect of the production of a Higgs-like element.
I don't have much faith in the particle that will inevitably called Higgs as in my opinion it is not the cause for or the vector for the property of mass.
Quantum Field Theory does appear to work but the very absence of a strong Higgs signal is a stumbling block for me, it should be abundant and it's not. Therefore there is an error in the maths of the Field for this interaction.
My stance has been, for more than 15 years, that its absence is as a result of our failure to define Gravity, our belief that gravity is bent spacetime is I feel fundamentally wrong and that gravity is a closer to an effect like time, a genuine 5th dimension with supraluminal interactions and these interactions provide both gravitation and mass.
I'l get off my particular hobby-horse and let you mull over the answer to what you really wanted to know and vexed you.
Cheers
Gene.
|
|
|
Bedazzled
4,088 posts
90 months
|
Any galaxy with a redshift greater than 1.4 is moving away from us faster than the speed of light, and so light emitted from that galaxy will never reach us. However the Hubble constant which defines this relationship is decreasing over time; if we were to observe galaxies passing a fixed point in space, the later galaxies would pass at a lower velocity than the earlier ones. The rapid decrease in the Hubble constant around the time of galaxy formation is the reason why light from objects receding faster than light at that time has been able to reach us. Initially the light would have been carried further away, but it persisted and eventually the expansion slowed enough for it to make progress towards us, and finally it arrived. The Hubble constant reducing by an order of magnitude is what enabled this to happen. Here is a distant galaxy with a redshift of 8.6; at 30 billion light-years away it is one of the most distant objects observed!
|
|
|
Blib
Original Poster
20,666 posts
66 months
|
Oh no. I'm lost again.
|
|
|
Gene Vincent
4,002 posts
27 months
|
Blib said: Oh no. I'm lost again. 30 bn light years away (distance) but only 13.3 or 13.4 bn (time) years ago. The difference is due to the period of inflation.
|
|
|
Blib
Original Poster
20,666 posts
66 months
|
Gene Vincent said: Blib said: Oh no. I'm lost again. 30 bn light years away but only 13.3 or 13.4 bn (light) years ago. The difference is due to the period of inflation. I do get that bit. It's just the 'moving away from us at faster than the speed of light' bit that jars on my addled brains. I shall read through it once more in the morning.
|
|
|
Gene Vincent
4,002 posts
27 months
|
Blib said: Gene Vincent said: Blib said: Oh no. I'm lost again. 30 bn light years away but only 13.3 or 13.4 bn (light) years ago. The difference is due to the period of inflation. I do get that bit. It's just the 'moving away from us at faster than the speed of light' bit that jars on my addled brains. When look that far out into space we are also looking back at time, so we can see what was going on then, it is as if we are watching a film relayed of something that happened long ago, there are errors in this and the arguments about redshift are very nicely nuanced, but fundamentally you are seeing into the past.
|
|
