Discussion in 'Astronomy, Exobiology, & Cosmology' started by Saint, Jun 17, 2009.
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the particles would for ever expand further away and never coalesce
But the expansion of space doesn't happen on the level of galaxies. Local gravity in that case is a stronger influence that overcomes the tendency to expansion.
to you it does
what does that tell you ?
It tells me you are trying not to live up to your user name. You are not thinking.
The expansion of space at short intervals (short meaning galactic scale) is small compared to the gravitational attraction due to the local concentration of matter.
Another analogy: Since gravity pulls you toward the center of the Earth, why doesn't gravity pull you through the floor? The answer is because the electrons in the atoms at the surface of your feet and the surface of the floor repel one another. Because matter is electrically neutral, this repulsive force drops off much, much quicker than does the Coulomb inverse square law. Jump off the floor by even a few millimeters off the floor and this repulsive force becomes vanishingly small until you land from your jump. Gravity and this repulsive force follow different power laws.
The same goes for gravity and the expansion of space. The follow different power laws. The metric expansion of space can be viewed as having the effect of a repulsive force that is proportional to the distance between objects. Gravity on the other hand is inversely proportional to the square of the distance between objects. At close distances, the gravitational force dominates over the expansion of space. At larger distances, the gravitational force between objects becomes vanishingly small while the expansion of space, viewed as a force, becomes very, very large.
First you try to tell me that I think the opposite of what I wrote, then you ask me to explain a statement that stands on its own without needing further explanation.
You seem to be trying to waste my time. If that is the case, I won't bother replying to you in future. Are you intending to waste my time?
thinking. The idea of science is that something is not just accepted because it looks right or because a certain set of circumstances make it seem right. Everything should always be under question.
However when it comes to the BB, it is deemed infallibly right by most and not to be questioned, so it isn't. That is not science. It is an all eggs in one basket scenario where if it eventually turns out to be correct, OK. If it doesn't, maybe a century has been lost exploring wrong paths and making the evidence fit with ever more unlikely explanations. A disaster.
James R. I would not insult someone by hinting they are wrong because they must be angry with me (as though that would make a difference to their answers).
Explain how a singularity can inflate while sticking to acceptable science and without using fairy tale terms.
If someone tries to win an argument by claiming intellect, they have already lost the argument.
If you agree, answer some questions then.
Euler is a friend of AlphaNumeric who also tried the "I'm smarter than you are" gambit, while being unable to answer even simple questions. His field was maths (hence the alias) and he seemed lost outside of it.
I believe the redshift is down to a sea of gravity rather than nothing somehow expanding.
If the universe is expanding, it is doing so despite the attractive force (gravity) of everything in the universe. As things get further apart, so the attractive force is weaker so doesn't slow down expansion as much. If this was true, then expansion would get ever faster till it reached a maximum speed where it is not slowed down by gravity.
I think a steady state universe possible but if someone could come up with firm evidence for something I else would drop the idea, since it is just an idea.
If nothing could change into something, there would be limitations as in one universe is not going to form inside another (though we might detect something on a quantum scale, like virtual particles). It would be like two puddles of water linking up. Distances would be such that unless we could detect them in some way (ie: it was happening within sight of our telescopes), we would never know. What we would see is a lot of blue shifted galaxies and clusters at the "edge of our universe".
But there is. In a 3D balloon-type expansion, everything would move away from everything else, but from a centre and effectively over long enough time, there would be nothing left in the centre. The sultanas in the pudding explanation still means everything moving away from a definite centre.
Of course in a galaxy, local gravity could just ignore expansion but outside, at what point could it not with very distant dwarf clusters, like these four, millions of light years from our galaxy:
That is a problem. You have the expansion of every single hydrogen atom away from every other hydrogen atom and none with sufficient mass to attract anything.
You have two possibilities here. That everything is so close it clumps but then again, why not just the lot clump a little earlier? Or clumping only occurs on the smallest scales so that a star would take many billions of years to form and there would be very few of them.
Far from being virtually uniform as the CMB tells us, the universe is anything but, all supposedly from the most minor perturbations on a quantum scale. We have huge voids upto a billion light years across. We have walls of hundreds of galaxies. The record holder for black holes is 18 billion solar masses but far bigger ones may exist. All this in less than 14 billion years.
Our galaxy is supposed to be about ten billion years old but one of the oldest stars in the universe is in our local neighbourhood, at 13.2 billion years old:
Like James R, I am not well versed in either BB or Steady State models, but AFAIK intitally at t = 0+ in the BB model there was only energy, which would be EM waves of very exteme energy - far beyound the harshest gamma rays we can imagine. Then to maintain charge neutrality, electons and positive quarks formed for the energy sea as it expanded (with the universe) and cooled. Neutral quarks were created the same way an I known no reason why they had to be in the same number as the charged ones. Later, with more cooling, protons and neutrons formed three quarks each. Probably some electrons briefly joined to the protons but the uinverse was so hot still that it was essentailly (> 99.9999%) a fully ionized plasma. The process of recombination and immediate reionization plus the Columb scatering assured that the electon and ion temperatures remained nearly the same as the colling continued. Also there were strong interaction between the EM waves and the charged particles that keep the EN waves with the black body temperature of the particles as the cooling continued.
Surely gravity, the electical forces and both the nuclear forces were separate when protons existed.* As the expansion and cooling continued, the electrons and the protons joined to make neutral atomic hydrogen (perhaps also some H2 but that union of two neutrals is not aid by Coulumb attraction and I think requires a "third body" to carry away the binding energy of at least capture into an excited state of the H2 molecule.)
Eventually allmost all the electrons had joined with protons so the interaqction with the EM waves which keep the Black Body EM spectrum temperature tied to the charged particle tempeature terminated. Then only the "stretching of space" with the expansion of the universe caused the EM field temperature to drop, to the current ~4K. which is called the CBR or (other names). Eventually the stars began to form under the influence of their masses mutual gravity (and quite possibly some locally denser region of "dark matter") They were trypically sevaral hundred times more massive than our puny sun. burned their fuel all the way to iron and exploded in powerful supernovas. Before they did this, they sent enormous energy as harsh UV mainly it space. This striped the electons from the neutral H and H2 and He to begin the "re-ionization" of space era, we still live in. (Space is so empty that even with the help of Coulumb attraction, electrons rarely find and recombine with the positive ions. (The Saha equation tells this "cold space is ionized" story mathematically. I happen to know of it as my experimental Ph.D. used plasma and Saha tells how much is ionized as fct of T and densities.)
*If not always - I think the std. POV is that initially these four "forces" were one and not distinguishable, or perhaps just too weak wrt the average thermal energy to have any significant effect. I like colorful analogies so perhaps they were always separate but:
No more effective than a flea's fart in a huricane.
But the tape measure (and the distance markings on it) is not part of the universe either. The only tape measure that would qualify here is one that is consistently integrated into the balloon surface, and here you have two options: a) either it is an elastic tape measure that expands together with the balloon (in which case the indicated distance would not change), or b) it is a rigid structure unaffected by the balloon expansion in which case it would drop out of the universe as the latter expands.
I specifically avoided comparing anything to the BB singularity as I agree; "singularity" is just a nice way to say: extrapolating from the region we think we understand everything seems to condense into a single point. Clearly then our mathematical models do not apply so we indicate this by saying: it is a "singularity." (I.e. nice way to wrap all our ingorance into one word.)
I asked you why the universe when NOT a singularity, but with volume 0.000,000,1 mm^3 did not collapse into a black hole? Perhaps you have the correct answer (Gravity did not yet exist OR a "negative gravity" did and was stronger) I was glad to note that you did not reverse yourself and say that thermal energy does not make a gravity field. I think it very unproductive to postulate the laws of physics were different back when the universe was very tiny, but not a singularity - that is an open path for any speculation one wishes.
I just pulled my 0.000,000,1 mm^3 out of thin air. I bet the entire mass of the universe (energy included) contained in a much larger volume (a cubic meter?) should collapse in to a black hole. Let’s call the max volume which should have collapsed into black hole "V” - Was physics different when the universe had volume V? - I think not. If physic then was same as now, then this failure to collapse is yet another flaw in the BB model which surely is not removed by some hand waving about "singularities." Time to drag out the "negative gravity" was stronger idea? The BB model seems to me to have more ad hoc patches than a hobo's discarded pants but, like you I do not know much (really nothing) about the math that is used to describe the early universe evolution.
"Inflation" is admitted to be a clever later postulated to rescue the BB theory. The absence of BB's predicted magnetic monopoles and the dominance of matter over anti-matter I think are still awaiting rescue. There is another serious problem called the "boundary problem" which I do not understand also in the BB model, I think, which conflicts with observations.
The BB model is reported to have predicted the observed abundances of the initial matter (H, D, He and Li) by selection of the ratio of photons to Baryons but that ratio can be adjusted to match ANY pair you want exactly and only gets a reasonable accurate value for one of the other two and misses by more than a factor of two on the final one, so I am not much impressed by this "light element fit." Also how do they know what the original ratios were and how accurately is it known? (Stars have been making many elements and transforming many into other, the light elements at least as much as the heavy ones.)
AFAIK the Steady State model does NOT have any of these inconsistencies but does not explain the abundance of the light elements. Perhaps there is some circular thought in the BB if, for example, initially ONLY protons appear suddenly in space and then very energetic collisions freed their three + three quarks? (I doubt that is what happened, perhaps not even possible, but bet some alternatives to the BB's light element generation do exist as only need to explain three (or four if Li is included) atoms. I also do not know why or how it is known that there was any Li made or that even within the BB model's very dense high energy of the matter formation era, there were no collisional events that reassembled quarks.
For me there is just too much that seems to be self contradictory (especially the absence of predicted anti-matter and magnetic monopoles) but I am probably just too ignorant. None the less, there should be at least some "dumbed down" story* I could understand or something in the Steady State equally self contradictory to make me not prefer it. I do not like just taking the word of the "experts" when they themselves admit to some of these contradictions still remaining, even after the addition of "inflation" kept the BB from being totally wrong in everything.
I thought the scientific method REJECTED theories with both internal contradictions AND predictions contary to observations.
*For example Hawking Radiation has two, mutually contradictory "dumbed down" stories. One has Black Body radiation carrying away the mass/energy the Black hole is losing. The other has one member of a vacuum polarization pair falling inside the Event Horizon and the other escaping to be new energy/ mass in our observable universe. The BB supporter have not been able to come up with even one "dumbed down" story for even one of the several internal conflicts, probably as they remain internal conflicts.
Again I note that I have given in post 69 & 79 about a dozen natural sources of radiation from accelerated charges that produce EM waves both shorter and longer than the peak of the CBR. (There are many more.) I also mentioned some of the various inter actions these EM waves have with charged matter (the same as the BB has) which cause the EM wave temperature to track the inter galactic particle temperatures. (EM field and particles remain in thermal equilibrium). Thus, the CBR does NOT, as most seem to think, support only the BB and not the Steady State model. - It fits naturally into either model requiring only a mechanism of EM to particle thermal coupling and even the same mechanism are applied to both!)
The steady state model also has the philosophical advantage of not needing a "first cause", such as a God.
You'll need to read up on the big bang theory for yourself, I'm afraid. I can't do all the work for you.
I have no idea what a "sea of gravity" is. It sounds like a term you just made up.
Yes, but it still slows it.
No. How could the expansion get faster, with gravity always pulling it back? Even if gravity gets weaker as the distances increase, gravity remains always an attractive force.
There's firm evidence for the big bang theory. Lots of it.
The closest thing in the analogy would be a rigid tape measure. Just like the tape measures in our real universe, electromagnetic forces keep the tape measure from expanding with the space around it. The possibility of "dropping out of the universe" is just pushing the analogy further than it needs to go.
What makes you think it isn't?
The big bang theory, like any other significant theory in science, has some unknowns to it. It is not deemed infallible.
The biggest problem with the big bang theory is that it somehow attracts attacks filled with hatred and lies -- i.e., yours.
This, for example, is a lie:
Since you are most like mouthing lies from some wacko site, I'll give you some slack this time. This is a lie in many ways.
Let's take for granted that these age of the Milky Way is indeed just 10 billion years. These ages do not contradict one another. Galaxies capture stars that were not originally part of the galaxy. Galaxies even capture other galaxies.
The Milky Way is not "supposed to be about ten billion years old." It is deemed to be one of the original galaxies formed soon after the Big Bang.
If you define the distances in our universe through some rigid (non-expanding) lattice system, then the balloon analogy (assuming some rigid lattice structure initially coinciding with the balloon surface) tells you that at the slightest amount of 'space expansion' all galaxies would immediately drop out of the lattice system (i.e. out of our physical universe). So in this sense you can't really say that this argument would be pushing the analogy too far. It just shows that the analogy doesn't demonstrate what it is supposed to do (because obviously galaxies are not dropping out of our universe).
Stop with the fallacious reasoning, Thomas. In the balloon analogy, the surface of the balloon is (represents) the universe. There is no place for the galaxies to "drop out of". There is no "rigid (non-expanding) lattice system" in the balloon analogy -- and there is no rigid (non-expanding) lattice system in our universe, either.
what other ad-hoc's will BB do in which to survive as a theory
so we are know considered the center of the Universe then ?Please Register or Log in to view the hidden image!
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the micrwave radiation can only eliminate just a few local galaxies as the source of CMBs , CMBs are a local thing , the whole of the Universe and the galaxies within it are not eliminated as a sourse of CMBs because we just don't have the technology to do so
so using CMBs as any type of support to any theory should not be used to explain the Universe as a whole, unless the theory is a very local theory and the rest of the Universe is not necessary in any said theory and this includes the BB theory
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