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Motion of the Primordial Universe Revealed
neutron_p writes "New results from an instrument located high in the Chilean Andes (the Cosmic Background Imager) are giving researchers a clearer view of what the universe looked like in the first moments following the Big Bang. Cosmologists observe a time in the universe's distant past when atoms were first forming. The findings reveal the first movements between these "seeds" that ultimately led to clusters of early galaxies."
New data suggests that the universe expanded rapidly in the first instants after the Big Bang
Which lead to renewed enthusiasm about the name, as apposed to previous suggestions:
The Big Yet Apathetic And Lethargic Singlular Point Of Spontaneous Existence Creation By Magic.
I believe that the Big Bang we hear are echoes of cosmic events that may have happened anywhere. I also think that there was a real bang, when reality and existence in thier mortal plane was created.
If you think that is more crazy than an inexplicable universe full of toothpicks, then please by all means explain yourself.
#hostfile 0.0.0.0 primidi.com 0.0.0.0 www.primidi.com 0.0.0.0 radio.weblogs.com
It's just a jump to the left and then a step to the right.
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
The artivel mentions nothing of the motion that is claimed in the Headline. Sure, it talks about what the results of their analysis of that motion is: support ofr Dark Matter and Dark Energy. Great. So what is this new understanding of motion they discovered.?
Anthony Readhead.... says the new polarization results provide strong support for the standard model of the universe as a place in which dark matter and dark energy are much more prevalent than everyday matter.
THank you Mr. Readhead, and now if we could have some more details, please.
.
-shpoffo
Don't microwaves move in a straigth line? In which case, shouldn't any radiation created by the big bang be at least 13 billion light years away from it's point of origin by now? So, unless they are reflecting off something or the universe wraps around at the edges, why can we still detect them? If they are reflecting off something, then aren't they really just mapping the density of whatever they are reflecting off of? I guess I'm just not clear on what makes this background radiation run around in circles...
"Freedom means freedom for everybody" -- Dick Cheney
The press release at the CBI website is much more informative.
The big news is that they've measured the polarized power spectrum, and it agrees extremely well with the theoretical predictions. Which means that not only do the density fluctuations match what's expected, but the matter is moving in the gravitational field of those density fluctuations exactly as expected.
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Basically an updated recipe for a pancake of extreme proportions; we now know whether there should be lumpy bits or not.
Will the real Anonymous Coward please stand up?
They never say how fast or dont know, but is it possible in theory that the expansion was faster than light?
Um, this particular aspect of the BBT has bothered me for awhile too. Presumably the universe and the matter in it could not expand more rapidly than light. Which means, one would suspect, that any radiation from the BB would be "ahead" of us traveling along the leading "edge" of the "inflation front" fron of the universe.
Now if you want to say that this means the universe is closed, I can see that, but would that not also mean that any radiation we see from "near the beginning" would have to be not less than twice as old as the universe, since it has had to completely traverse the circumference - so to speak - of the universe in order to reach us?
------ The only greater hazard to your liberty than n politicians is n+1 politicians.
In fact, the expansion of the universe doesn't have a physical velocity associated with it - it's a fractional rate of change. So if the universe expands at "0.1 Gyr^-1", then proper distances increase by 10% per gigayear (*). If the distance you're interested in is larger than 10 billion light years, then it increases at faster than the speed of light. But that same rate of expansion corresponds to a much smaller velocity if you're dealing with a much smaller distance.
A photon's important length is its wavelength, lambda. This wavelength increases because of universal expansions at a rate of lambda * H_0... or about 10^-24 m/s for an optical photon (wavelength of 500nm). But this isn't even a real velocity, it's just the rate of change of the wavelength - even if it were greater than the speed of light, it has nothing to do with causality.
(*) This rate of expansion (also known as the Hubble constant, H_0) is, for historical reasons, usually expressed in units of km/s/Mpc... but you'll notice that the km and Mpc cancel out, giving a fractional rate. If the Hubble constant is 70 km/s/Mpc (consistent with current measurements), that is equal to 0.072 Gyr^-1.
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Oooo-kay, this may be why I went into archaeology.
Hubble's constant is a ratio scale measure, the "speed" is protportionate to the distance being discussed. I remember that much from college physics. Now, I also remember George Gamow, in one of his books via a raisin bread analogy, explaining the red shift limit as a function of the expansion of the universe, and saying more or less that the apparent speed that remote bodies are receding is due to the cumulative expansion of the space in between. The farther apart two raisins in a loaf are, the faster they appear to separate as the loaf rises. We could n't see back to the BB because it was beyond the red-shift limit for us.
If I understood what you wrote though, it seemed that you are suggesting that the relative rate of separation between two remote bodies can be greater than SOL (e.g. the most separated of Gamow's "raisins"), but the article is implying that we can see almost all the way back to the BB.
If I understand the figures you used, then if the universe is 15 Gy across, then it will expand about 1.5 Gy in the next Gy. That looks as if it might mean that the universe is expanding 1.5 ly every year - more less. Wouldn't that mean that the objects far out on the opposite "edges" are "apparently" booking along faster than light relative to each other simply because the universe continues ot inflate?
Anyway thanks for the effort to unconfuse me.
------ The only greater hazard to your liberty than n politicians is n+1 politicians.
No mod points at the moment, so I'll just have to thank you. :)
For example, let's imagine a photon leaving an object that is currently moving away from us at about 25% faster than the speed of light. At the time the photon is emitted, the distance between us and the object was much smaller, and so the relative velocity was much smaller than the speed of light. So the photon easily traverses a large fraction of the distance. Now it's 3/4 of the way to us, and the original object is expanding away from us at the speed of light. But the distance the photon has left to travel is only 1/4 of that, so the recession velocity is only 1/4 of the speed of light, and it has no problems travelling the rest of the way.
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Zeno would have loved that discourse. You still have me wondering about the relativity of relativity so to speak. Partly of course, I asked a question that more or less begs for an interpretation of a "simulataneous" state between to very remote objects, which Einstein I think described as a nonsensical concern. Still, in this universe, can two objects have relative speeds that are greater than the speed of light? I guess my problem is that I more or less got the idea that the the BB involved an object of extremely small dimensions - again that doesn't make much sense if both space and time are really products of the BB. Any way, I assumed that once we have space and time, also those oldest photons would have gone bucketing on past any matter in the vicinity, have to have. But perhaps it was more or less zooming straight around some intensely curved geodesics, straight ahead all the way around space-time? That doesn't seem to add up however with a proposal that the universe was expanding faster than light. Nor does it really seem clear if 1) space expands faster than light, 2) it carries matter with it, and 3) old light is just catching up with us.
Isn't more that old light is coming back from a long trip that more or less circumnavigates space time? Regardless of which direction a telescope looks, it looks back in time, and it sees much the same structure of space and matter. If the BB is what produced space-time, then the remote sky that surrounds us has to represent a smaller universe than what we now occupy, no? So, that remotest, ancient image has to be more distorted than a fun house mirror, doesn't it? And reasonably, you can suspect that some of the matter we can see way, way out there near the beginning of time is the same as what we see when we are looking in some other direction? My head hurts.
------ The only greater hazard to your liberty than n politicians is n+1 politicians.