What does it mean for space-time itself to expand? Expand into what? What caused the big bang? What caused inflation? If time itself began with the big bang then how could the big bang “start” before time existed? How can we have cause and effect without time?
The big bang theory of the universe has much in common with the Universe of Aristotle and Ptolemy of the solar system.
Aristotle and Ptolemy held that the sun and all of the planets orbited the earth. We can see exactly the same distance, and by extension time, in all directions. The microwave background glow is nearly uniform in all directions. Again we find ourselves at the center of the universe.
They relied upon epicycles, circular orbits within circular orbits, to explain the motions of the Sun and planets around the earth. Modern cosmology requires a cosmically constant, dark matter, dark energy, inflation, and expansion. No combination of cosmological constant value, age of the universe, and matter within the universe, dark matter and dark energy included, can simultaneously be self-consistent and consistent with the observed universe.
The net effect of a positive cosmological constant is to create a negative gravitational force that drives the expansion of the universe. As the universe expands, matter and energy are spread out over more physical space and thus their gravitational attraction is diminished.
The work done by the vacuum during expansion provides exactly the amount of energy to fill the new volume to the same density, therefore the cosmological constant remains constant and by extension the repulsive gravitational force driving expansion remains constant while gravitational attraction diminishes as matter and energy become less dense.
This conflicts with another ad-hoc requirement of the big bang theory, inflation, a period of rapid expansion. If the cosmological constant remains truly constant and thus it’s gravitational repulsive force remains constant, then what we should observe is a logarithmic increase in the expansion rate from the point of the big bang forward which is inconsistent with inflation.
Decades ago I read a book by Eric Learner entitled, “The Big Bang Never Happened”. The central thesis of the book is that the universe is a “steady-state” universe that has always and will always exist. While there were some errors of logic, the view presented of a possible steady state universe is interesting if incomplete.
An element of his theory was that electromagnetic forces play a far greater role in the evolution of the universe than do gravitational forces. This mechanism allowed for example the transfer of angular momentum from young rapidly rotating stars to a forming planetary system.
Eric postulates some mechanism gradually reduces a photons energy over distance other than Doppler shift caused by the motion of expansion. This is referred to as the “tired light” theory. Quantized red shift red shift and descrepencies between the red shifts in cores of spiral galaxies and their spiral arms supports this notion. And yes I do realize you get Doppler broadening because of the rotation of the galaxies.
When I saw the first Hubble deep field images, the galaxies I saw were markedly different than modern galaxies, oddly shaped, irregular, and clumpy. For a long time that shifted my perspective away from a steady state universe. If not a big bang, there appeared at least to be a universe that had undergone substantial evolution over time.
But then I saw images of nearby galaxies in ultraviolet light. Low and behold, they were oddly shaped, irregular, and clumpy. In fact they looked amazingly like the galaxies in the deep field hubble images. And then it occurred to me the deep field images taken in visible light were actually seeing extreme UV from the distant galaxies red shifted into the visible spectrum. The reason these galaxies appeared oddly shaped, irregular, and clumpy is because looking in the visible spectrum here, we are only seeing the regions of active star formation with young very hot stars which have substantial spectral output in the extreme UV range. The major portions of those galaxies were invisible to us looking at them in the visible spectrum.
When the first deep field images came back from the Spitzer, looking at the far infrared light, light that originated as visible light when it left those distant galaxies, what I saw were large spiral galaxies and other familiar forms. The universe then looked very much as it does today.
Carbon monoxide has been detected in the spectrum of the oldest quasar examined. Big bang theorists suggest that this is because the first generation of stars were very massive and short lived and rapidly converted hydrogen to heavy elements, exploded into super novas and distributed these elements throughout the early universe. But an alternate explanation is that the metalicy of the universe has been maintained roughly constant through some unknown mechanism over the eons.
Distant Quasars Probe End of Cosmic Dark Ages by Lori Stiles is an interesting article dealing width distant quasers.
| “But we see a lot of other elements around those early quasars,” Fan said. “We see evidence of carbon, nitrogen, iron and other elements, and it’s not clear how these elements got there. There is as much iron, proportionate to the population of those early systems, as there is in mature galaxies nearby.” |  |
The tiny red dot in the center of this image is the most distant quasar ever discovered. The object is roughly 13 billion light years away. UA astronomer Xiaohui Fan led the Sloan Ditigal Sky Survey that discovered this and other ancient quasars.(Photo: Sloan Digital Sky Survey)
This doesn’t seem to argue for a big bang followed by a universe in which hydrogen is converted to heavy elements in stars. It would seem that there is some mechanism maintaining some sort of equilibrium, removing heavy elements and providing fresh hydrogen over the possibly unbounded life of the universe. If that is the case it also favors the idea that what we see when we look out 13.6 billion light years is a horizon of sorts. The universe might be infinite, or merely more enourmous than we presently appreciate.
I intend to address specific point in your page but first for anyone interested in cosmology, this is an excellent introduction:
Ned Wright’s Tutorial
Now let’s look at your page in detail. I’ll quote most and omit some background to save space:
“What does it mean for space-time itself to expand? Expand into what?”
Firstly we should clarify that the so called “Big Bang” model describes space expanding as a function of cosmological time. What does it mean for space to expand? It just means everything
tends to get farther away from everything else. Locally, gravitational forces tend to draw things together so there are a competition on small scales but beyond a few hundred millon light years, expansion is dominant.
“What caused the big bang? What caused inflation?
We don’t know, and that is the essence of science, we observe the universe and learn what observation tells us, but where we cannot answer a question, we admit that. We know the universe was denser in the past and everything is moving apart now, and the model of inflation is our only working explanation of certain measurements, but although we observe these effects, we cannot yet say why they happened.
“If time itself began with the big bang then how could the big bang “start” before time existed? How can we have cause and effect without time?”
Again we don’t no, but in quantum mechanics events do occur without cause so this isn’t really a problem.
“Aristotle and Ptolemy held that the sun and all of the planets orbited the earth. We can see exactly the same distance, and by extension time, in all directions. The microwave background glow is nearly uniform in all directions. Again we find ourselves at the center of the universe.”
We do but think for a moment. Imagine your self on a flat plain miles across on a foggy day. The visibility in is only 100yards. You can see exactly the same distance in every direction, 100yards, but that doesn’t mean you are in the middle of the plain. Someone just a the limit of tyour vision would also have exactly the same experience.
Big bang models do not put us at the centre, in fact they all tell us there is no centre.
“No combination of cosmological constant value, age of the universe, and matter within the universe, dark matter and dark energy included, can simultaneously be self-consistent and consistent with the observed universe.”
This set:
Omega_vacuum: 73%
Dark matter: 23%
Baryonic matter: 4%
Age: 13.7 billion years
Fit all observations and are self-consistent. The WMAP results suggest the characteristics of ‘dark energy’ fit better to a cosmological constant than the main alternative, ‘quintessence’.
“The net effect of a positive cosmological constant is to create a negative gravitational force that drives the expansion of the universe. As the universe expands, matter and energy are spread out over more physical space and thus their gravitational attraction is diminished. The work done by the vacuum during expansion provides exactly the amount of energy to fill the new volume to the same density, therefore the cosmological constant remains constant and by extension the repulsive gravitational force driving expansion remains constant while gravitational attraction diminishes as matter and energy become less dense.”
Other explanations exist though a constant effect is a better fit to the data.
“This conflicts with another ad-hoc requirement of the big bang theory, inflation, a period of rapid expansion. If the cosmological constant remains truly constant and thus it’s gravitational repulsive force remains constant, then what we should observe is a logarithmic increase in the expansion rate from the point of the big bang forward which is inconsistent with inflation.”
Here yo go beyond what we know. Inflation is not well understood but clearly with exponential expansion, it is unlikely that there would be time for equilibrium to be maintained. There is no conflict here, you are trying to apply a conclusion derived in the absence of inflation to the inflationary scenario.
“Decades ago I read a book by Eric Learner entitled, “The Big Bang Never Happened”. The central thesis of the book is that the universe is a “steady-state” universe that has always and will always exist. While there were some errors of logic, the view presented of a possible steady state universe is interesting if incomplete.”
Errors in the Lerner’s book
“Eric postulates some mechanism gradually reduces a photons energy over distance other than Doppler shift caused by the motion of expansion. This is referred to as the “tired light” theory.”
This was not Eric’s but was suggested by Zwicky in 1929. It has been thoroughly refuted.
Errors in Tired Light
In particular:
Timescale Stretch Parameterization of Type Ia Supernova
Of course this information was not avalable to Lerner and in Zwicky’s time the idea was quite reasonable.
“Quantized red shift red shift and descrepencies between the red shifts in cores of spiral galaxies and their spiral arms supports this notion. And yes I do realize you get Doppler broadening because of the rotation of the galaxies.”
Halton Arp’s suggestion of ‘quantized red shift red shift’ (sic) has long ago been shown to be an artefact of the some number of samples available at the time. Recent advances in telescopes (such as the Hubble) have extended our observations and eliminated this idea.
I am not aware of the ‘discrepancies’ you mention.
“Carbon monoxide has been detected in the spectrum of the oldest quasar examined. Big bang theorists suggest that this is because the first generation of stars were very massive and short lived and rapidly converted hydrogen to heavy elements, exploded into super novas and distributed these elements throughout the early universe.”
Calculation of the mass of “population III” stars comes out around 200 times the mass of the Sun. Such massive stars have very short lives. In fact the current generation of telescopes is just starting to let us see the infra-red background produced by these explosions.
The First Supernova Explosions in the Universe
“Distant Quasars Probe End of Cosmic Dark Ages by Lori Stiles is an interesting article dealing width distant quasers.”
“This doesn’t seem to argue for a big bang followed by a universe in which hydrogen is converted to heavy elements in stars. It would seem that there is some mechanism maintaining some sort of equilibrium, removing heavy elements and providing fresh hydrogen over the possibly unbounded life of the universe.”
Errors in the Steady State and Quasi-SS Models
That neglects the fact that we see other significant changes in composition of stars. Population II stars are identifiable precisely because they have very low metallicity. Further the mix of hydrogen and helium is precisely what a big bang would produce and the existence of primordial deuterium is a major problem for steady state since it cannot be produced by other means.
Nucleosynthesis
“If that is the case it also favors the idea that what we see when we look out 13.6 billion light years is a horizon of sorts.”
It certainly is, caused by the time when the gas was so dense it was opaque, some 378 thousand years after the bang.
“The universe might be infinite, or merely more enourmous than we presently appreciate.”
The big bang says the universe is probably infinite in size, or at least 1000 times larger than we can observe. The WMAP results strongly suggest a ‘flat’ (or Euclidean) geometry for the universe which would be infinite in size.
George
George Dishman said:
“What does it mean for space-time itself to expand? Expand into what?”
Firstly we should clarify that the so called “Big Bang” model describes space expanding as a function of cosmological time. What does it mean for space to expand? It just means everything tends to get farther away from everything else. Locally, gravitational forces tend to draw things together so there are a competition on small scales but beyond a few hundred millon light years, expansion is dominant.
Nanook Replies:
There is a non-trivial difference between the proposed cosmological expansion and as you say, everything tends to get farther from everything else.
Everything tending to get farther from everything else is something that happens IN space, it is limited by the speed of light, but as I understand it this is not the case for cosmological expansion where space itself expands.
George Dishman writes:
“What caused the big bang? What caused inflation?
We don’t know, and that is the essence of science, we observe the universe and learn what observation tells us, but where we cannot answer a question, we admit that. We know the universe was denser in the past and everything is moving apart now, and the model of inflation is our only working explanation of certain measurements, but although we observe these effects, we cannot yet say why they happened.
Nanook Replies:
I don’t think mainstream science does admit it. The big bang theory is not consistant with observation. We don’t know that the universe was denser in the past, what we know is that light from distant objects is red-shifted, and more distant objects are red-shifted more.
From that everything else is extrapolation. First, we assume all of the red-shift is Doppler in nature, but we don’t know that.
Only if it is Doppler can we assume everything is moving away from us and everything else. But since we do not know with certainty that it is Doppler, we can not justifiably assume that.
And then we go further to extrapolate that theoretical expansion of the universe, based upon the assumed Doppler shift, all the way back to a single point. We can’t see that far back, we have no way of knowing if in fact the universe ever was a single point, even if the assumption with respect to red shift is correct.
Inflation violates all known physical laws, and given that very early stars and galaxies and even clusters of galaxies appear essentially identical to modern galaxies, we have to assume the laws of physics haven’t changed radically, else things like atoms and stars couldn’t exist. But we see their light so we know they exist.
The fact that it helps make a flawed theory work doesn’t make it valid, the theory is broke, there is no good reason to invoke magic that violates all the known laws of physics to justify a broken theory.
George Dishman writes:
“If time itself began with the big bang then how could the big bang “start” before time existed? How can we have cause and effect without time?”
Again we don’t no, but in quantum mechanics events do occur without cause so this isn’t really a problem.
Nanook Replies:
You don’t understand the event that is central to the theory but that isn’t a problem?
Not understanding the cause doesn’t mean no cause exists. We know quantum effects exist, my computers hard drive and transistors wouldn’t function without them. Recent experiements have shown that hydrogen becomes metallic at pressures far less and temperatures far greater than our present understanding of quantum mechanics predicts. Our understanding clearly is incomplete.
But whatever the proposed cause was, if time was created in the big bang then it couldn’t have caused the big bang because without time you can’t have cause and effect.
George Dishman said…
“Aristotle and Ptolemy held that the sun and all of the planets orbited the earth. We can see exactly the same distance, and by extension time, in all directions. The microwave background glow is nearly uniform in all directions. Again we find ourselves at the center of the universe.”
We do but think for a moment. Imagine your self on a flat plain miles across on a foggy day. The visibility in is only 100yards. You can see exactly the same distance in every direction, 100yards, but that doesn’t mean you are in the middle of the plain. Someone just a the limit of your vision would also have exactly the same experience.
Big bang models do not put us at the centre, in fact they all tell us there is no centre.
Nanook replies:
Your foggy day anology does not hold with the big bang because the present day accepted age of the universe, per the big bang model, is 13.7 billion years, we can see almost that far now, and we can see the microwave remnant postulated to be the big bang event red-shifted into the microwave range. And when we look at that microwave background,it is extremely uniform.
If there was a big bang then we’re right at the center. Postulating that center exists only makes sense in the context of an infinite universe, and in that context, the big bang makes absolutely no sense because originating from a point space could not have expanded to infinitity unless it happened an infinite time ago, and that is essentually a steady state universe.
George Dishman says:
“No combination of cosmological constant value, age of the universe, and matter within the universe, dark matter and dark energy included, can simultaneously be self-consistent and consistent with the observed universe.”
This set:
Omega_vacuum: 73%
Dark matter: 23%
Baryonic matter: 4%
Age: 13.7 billion years
Nanook writes:
Not unless you ad the ad-hoc values of the cosmological constant and inflation.
Inflation violates the laws of physics. Since the very earliest stars and galaxies and even clusters of galaxies we observe exist and appear normal, and even slight changes in the laws of physics would preclude their existance, we have to assume the laws of physics applied even way back when.
George Dishman:
“This conflicts with another ad-hoc requirement of the big bang theory, inflation, a period of rapid expansion. If the cosmological constant remains truly constant and thus it’s gravitational repulsive force remains constant, then what we should observe is a logarithmic increase in the expansion rate from the point of the big bang forward which is inconsistent with inflation.”
Here yo go beyond what we know. Inflation is not well understood but clearly with exponential expansion, it is unlikely that there would be time for equilibrium to be maintained. There is no conflict here, you are trying to apply a conclusion derived in the absence of inflation to the inflationary scenario.
Nanook Replies:
You don’t understand inflation but you’re willing to accept it because it makes an otherwise flawed theory, when a few other ad-hoc variables like the cosmic constant are thrown in, work.
And I don’t see where you say this is going beyond what we know, certainly not to the degree the big bang theory is. Cause and effect before time, or effect without cause, the first violates laws of logic, the second laws of physics.
George Dishman says:
“Quantized red shift red shift and descrepencies between the red shifts in cores of spiral galaxies and their spiral arms supports this notion. And yes I do realize you get Doppler broadening because of the rotation of the galaxies.”
Halton Arp’s suggestion of ‘quantized red shift red shift’ (sic) has long ago been shown to be an artefact of the some number of samples available at the time. Recent advances in telescopes (such as the Hubble) have extended our observations and eliminated this idea.
I am not aware of the ‘discrepancies’ you mention.
Nanook Replies:
From what I have read, quantitization of red-shifts is still being argued.
Relying on the measurements of only one instrument is risky.
I wasn’t able to find the article regarding discrepencies between redshifts of galactic cores and spiral arms, but here is a very similiar situation:
http://www.thunderbolts.info/tpod/2005/arch05/050211thirtyyears.htm
In this article, a picture is shown of a glaxy and galactic companion connected by a filament but they have substantially different redshifts.
George Dishman writes:
“Carbon monoxide has been detected in the spectrum of the oldest quasar examined. Big bang theorists suggest that this is because the first generation of stars were very massive and short lived and rapidly converted hydrogen to heavy elements, exploded into super novas and distributed these elements throughout the early universe.”
Calculation of the mass of “population III” stars comes out around 200 times the mass of the Sun. Such massive stars have very short lives. In fact the current generation of telescopes is just starting to let us see the infra-red background produced by these explosions.
The First Supernova Explosions in the Universe
“Distant Quasars Probe End of Cosmic Dark Ages by Lori Stiles is an interesting article dealing width distant quasers.”
“This doesn’t seem to argue for a big bang followed by a universe in which hydrogen is converted to heavy elements in stars. It would seem that there is some mechanism maintaining some sort of equilibrium, removing heavy elements and providing fresh hydrogen over the possibly unbounded life of the universe.”
Errors in the Steady State and Quasi-SS Models
That neglects the fact that we see other significant changes in composition of stars. Population II stars are identifiable precisely because they have very low metallicity. Further the mix of hydrogen and helium is precisely what a big bang would produce and the existence of primordial deuterium is a major problem for steady state since it cannot be produced by other means.
Nanook replies:
The current generation of infrared telescopes are showing us an early population of stars, galaxies, and galactic clusters that look very much like todays stars, galaxies, and galactic clusters.
Further, if the big bang hypothesis is correct, these massive stars wouldn’t have the Carbon-Nitrogen-Oxygen catalytic fusion cycle available to fuse hydrogen into helium and would have to rely solely on p-to-p chain reactions, which are not normally the dominant reaction in massive stars. Therefore, those stars would not have burned their hydrogen as fast as their mass otherwise would indicate.
But as it happens we can see carbon monoxide in the very earliest stars, and if carbon was present, the CNO cycle would have been operating but that is inconsistant with the big bang hypothesis.
With regards to metallicy between population II and population III stars, you are using circular logic.
You are assuming that differences in metallicy are due to the stars being 2nd or 3rd generation stars when in fact other explanations exist. Metallicy is highest in stars in the galactic core and lowest in the outer reaches of the galaxy. Stars forming first in the core is one possible explanation, but gravitational stratification is another. That is to say, that as the cloud of hydrogen and heavier elements contracted enough for star formation to begin, the heavier elements were naturally drawn to the center of gravity.
George Dishman writes:
The big bang says the universe is probably infinite in size, or at least 1000 times larger than we can observe. The WMAP results strongly suggest a ‘flat’ (or Euclidean) geometry for the universe which would be infinite in size.
Nanook Replies:
If the big bang is correct expansion happens at a subinfinite speed. It is not possible to have an infinite universe come disperse from a single point in finite time. And if an infinite universe exists for infinite time, that is the very definition of a steady state universe.
Dishman said:
Firstly we should clarify that the so called “Big Bang” model describes space expanding as a function of cosmological time. What does it mean for space to expand? It just means everything tends to get farther away from everything else. …
Nanook Replies:
There is a non-trivial difference between the proposed cosmological expansion and as you say, everything tends to get farther from everything else.
Everything tending to get farther from everything else is something that happens IN space, it is limited by the speed of light, but as I understand it this is not the case for cosmological expansion where space itself expands.
GD: That’s true and as you say it makes a difference at large scales.
George Dishman writes:
[Nanook asked:]
“What caused the big bang? What caused inflation?
GD: We don’t know, and that is the essence of science, we observe the universe and learn what observation tells us, but where we cannot answer a question, we admit that. We know the universe was denser in the past and everything is moving apart now, and the model of inflation is our only working explanation of certain measurements, but although we observe these effects, we cannot yet say why they happened.
Nanook Replies:
I don’t think mainstream science does admit it. …
GD: You won’t find any mainstream scientist who says we have the whole picture.
N: The big bang theory is not consistant with observation.
GD: Not true, there are some observations that appear at odds with some models, and personally I think our views on galaxy formation shortly will need to be revised significantly, but overall there is nothing that contradicts the big picture.
N: We don’t know that the universe was denser in the past, what we know is that light from distant objects is red-shifted, and more distant objects are red-shifted more.
GD: We do know it was hotter and denser. First we can measure the temperature of isolated clouds of gas which are in equilibrium with the CMBR and those farther away have a higher temperature. Second we can measure the CMBR and we know it had a temperature of about 3000K when the universe was 378,000 years old. Third we can count galaxies at high redshift and they are denser than at present.
N: From that everything else is extrapolation. First, we assume all of the red-shift is Doppler in nature, but we don’t know that.
GD: We do because high Z supernovae show stretching of the light curve that rules out the alternative “tired light”. So did other measurements but that is perhaps the most robust.
GD: Only if it is Doppler can we assume everything is moving away from us and everything else. But since we do not know with certainty that it is Doppler, we can not justifiably assume that.
GD: Note also as you drew the distinction of movement within space against expnasion of space, the explanation is not quite pure Doppler but that’s a technical detail.
N: And then we go further to extrapolate that theoretical expansion of the universe, based upon the assumed Doppler shift, all the way back to a single point. We can’t see that far back, we have no way of knowing if in fact the universe ever was a single point, even if the assumption with respect to red shift is correct.
GD: Again this is a strawman, only laymen try to extrapolate all the way back. Quantum effects certainly become important before then and there are regions around “GUT” where we have no way to extrapolate.
N: Inflation violates all known physical laws, …
GD: Obviously it doesn’t or we wouldn’t be able to calulate its effects. Those calculations give answers that match observation better than the alternative “quintessence” according to the WMAP results.
N: …and given that very early stars and galaxies and even clusters of galaxies appear essentially identical to modern galaxies, we have to assume the laws of physics haven’t changed radically, else things like atoms and stars couldn’t exist. But we see their light so we know they exist.
The fact that it helps make a flawed theory work doesn’t make it valid, the theory is broke, there is no good reason to invoke magic that violates all the known laws of physics to justify a broken theory.
GD: The reason is simple, the measurements require it.
George Dishman writes:
[Nanook asked:]
“If time itself began with the big bang then how could the big bang “start” before time existed? How can we have cause and effect without time?”
GD: Again we don’t know, but in quantum mechanics events do occur without cause so this isn’t really a problem.
Nanook Replies:
You don’t understand the event that is central to the theory but that isn’t a problem?
GD: Again you make the same mistake, the start isn’t “central to the theory”, in fact it plays no part in it. The theory works back from the present day and is robust until before the era of nucleosynthesis about 1s after the initial event. Beyond that we don’t have theories (tested sets of equations) that will model what happened, that frontier is still being pushed.
N: Not understanding the cause doesn’t mean no cause exists. We know quantum effects exist, my computers hard drive and transistors wouldn’t function without them.
GD: We know effects exist but we also know they often don’t require a matching cause. Radioactive decay is the obvious example, the decay is spontaneous and has no cuase, only a statistical probability of occurring.
N: Recent experiements have shown that hydrogen becomes metallic at pressures far less and temperatures far greater than our present understanding of quantum mechanics predicts. Our understanding clearly is incomplete.
GD: Of course, nobody is disputing that.
N: But whatever the proposed cause was, if time was created in the big bang then it couldn’t have caused the big bang because without time you can’t have cause and effect.
GD: None was needed, it was a quantum event.
George Dishman said…
[Nanook asked:]
“Aristotle and Ptolemy held that the sun and all of the planets orbited the earth. We can see exactly the same distance, and by extension time, in all directions. The microwave background glow is nearly uniform in all directions. Again we find ourselves at the center of the universe.”
GD: We do but think for a moment. Imagine your self on a flat plain miles across on a foggy day. The visibility in is only 100yards. You can see exactly the same distance in every direction, 100yards, but that doesn’t mean you are in the middle of the plain. Someone just a the limit of your vision would also have exactly the same experience.
Big bang models do not put us at the centre, in fact they all tell us there is no centre.
Nanook replies:
Your foggy day anology does not hold with the big bang because the present day accepted age of the universe, per the big bang model, is 13.7 billion years, we can see almost that far now, and we can see the microwave remnant postulated to be the big bang event red-shifted into the microwave range. And when we look at that microwave background,it is extremely uniform.
GD: That’s right, we are in a fog where the visibility is limited to 13.7 billion light years but suppose the field we are in is 10,000 billion light years across? Or more accurately what if it is infinite?
N: If there was a big bang then we’re right at the center.
GD: That may be your opinion, it is not what the scientific model says. The equations say it is infinite and has no centre for us to be at.
N: Postulating that center exists only makes sense in the context of an infinite universe, and in that context, the big bang makes absolutely no sense because originating from a point space could not have expanded to infinitity unless it happened an infinite time ago, and that is essentually a steady state universe.
GD: The present most likely version of the theory says that when the universe formed it was infinite in size and very dense and that it has been expanding ever since. Your objections are aimde at an alternative that bears no resemblance to the actual theory.
George Dishman says:
[Nanook said:]
“No combination of cosmological constant value, age of the universe, and matter within the universe, dark matter and dark energy included, can simultaneously be self-consistent and consistent with the observed universe.”
GD: This set:
Omega_vacuum: 73%
Dark matter: 23%
Baryonic matter: 4%
Age: 13.7 billion years
Nanook writes:
Not unless you ad the ad-hoc values of the cosmological constant and inflation.
GD: That is how science works, we determine values by measurement. The above values are self-consistent and consistent with almost all observations. Inflation was originally inferred because of ‘flatness’, the uniformity of the background. The amplitudes of the CMBR angular power spectrum peaks have been measured by WMAP and the values predicted by inflation are correct while the values predicted by at least one alternative were wrong, so evidence is building for inflation.
N: Inflation violates the laws of physics. Since the very earliest stars and galaxies and even clusters of galaxies we observe exist and appear normal, and even slight changes in the laws of physics would preclude their existance, we have to assume the laws of physics applied even way back when.
GD: Not at all, the effects of inflation decayed and became negligible after about 10^-32s. Stars didn’t start forming until millions of years later.
George Dishman:
[Nanook said:]
“This conflicts with another ad-hoc requirement of the big bang theory, inflation, a period of rapid expansion. If the cosmological constant remains truly constant and thus it’s gravitational repulsive force remains constant, then what we should observe is a logarithmic increase in the expansion rate from the point of the big bang forward which is inconsistent with inflation.”
GD: Here you go beyond what we know. Inflation is not well understood but clearly with exponential expansion, it is unlikely that there would be time for equilibrium to be maintained. There is no conflict here, you are trying to apply a conclusion derived in the absence of inflation to the inflationary scenario.
Nanook Replies:
You don’t understand inflation but you’re willing to accept it because it makes an otherwise flawed theory, when a few other ad-hoc variables like the cosmic constant are thrown in, work.
GD: The theory isn’t flawed, what GR tells us appears to be accurate. Inflation resolves a different problem to do with thermodynamics where temperatures over the sky are more uniform than was expected. That is called empirical science and is considered the most robust form. For example all the science of electricity and magnetism started with simple laws from observation of coils and leyden jars. Later Maxwell put them together and showed how they explained light but the basis was observation.
N: And I don’t see where you say this is going beyond what we know, certainly not to the degree the big bang theory is.
GD: I meant the bit about “If the cosmological constant remains truly constant and thus it’s gravitational repulsive force remains constant..”. That is still being measured and it is too early to say. However, you arer right that it would produce exponential expansion. In fact the initial data from supernovae suggested that is what has been happening for about the last 6 billion years which is why the constant is now considered to be non-zero. Up until then almost every scientist expected it to be zero but the measurements surprised us.
N: Cause and effect before time, or effect without cause, the first violates laws of logic, the second laws of physics.
GD: Effect without cause is what happens when any radioactive material decays and is utterly fundamental to QM.
George Dishman says:
[Nanook said:]
“Quantized red shift red shift and descrepencies between the red shifts in cores of spiral galaxies and their spiral arms supports this notion. And yes I do realize you get Doppler broadening because of the rotation of the galaxies.”
GD: Halton Arp’s suggestion of ‘quantized red shift red shift’ (sic) has long ago been shown to be an artefact of the some number of samples available at the time. Recent advances in telescopes (such as the Hubble) have extended our observations and eliminated this idea.
I am not aware of the ‘discrepancies’ you mention.
Nanook Replies:
From what I have read, quantitization of red-shifts is still being argued.
GD: No, there are about half a dozen serious people that are still looking but properly conducted surveys have shown no quantisation.
N: Relying on the measurements of only one instrument is risky.
GD: Many instruments have been used and many surveys performed.
N: I wasn’t able to find the article regarding discrepencies between redshifts of galactic cores and spiral arms, but here is a very similiar situation:
http://www.thunderbolts.info/tpod/2005/arch05/050211thirtyyears.htm
In this article, a picture is shown of a galaxy and galactic companion connected by a filament but they have substantially different redshifts.
GD: OK, good example. Obviously this can be just an alignment, there are vast numbers of these, but I will have to dig around to see what the story is on that one.
George Dishman writes:
[Nanook said:]
“Carbon monoxide has been detected in the spectrum of the oldest quasar examined. Big bang theorists suggest that this is because the first generation of stars were very massive and short lived and rapidly converted hydrogen to heavy elements, exploded into super novas and distributed these elements throughout the early universe.”
GD: Calculation of the mass of “population III” stars comes out around 200 times the mass of the Sun. Such massive stars have very short lives. In fact the current generation of telescopes is just starting to let us see the infra-red background produced by these explosions.
The First Supernova Explosions in the Universe
{see ealrier comments for links, the software does not appear to carry them through}
N: “Distant Quasars Probe End of Cosmic Dark Ages by Lori Stiles is an interesting article dealing width distant quasers.”
“This doesn’t seem to argue for a big bang followed by a universe in which hydrogen is converted to heavy elements in stars. It would seem that there is some mechanism maintaining some sort of equilibrium, removing heavy elements and providing fresh hydrogen over the possibly unbounded life of the universe.”
GD: Errors in the Steady State and Quasi-SS Models
That neglects the fact that we see other significant changes in composition of stars. Population II stars are identifiable precisely because they have very low metallicity. Further the mix of hydrogen and helium is precisely what a big bang would produce and the existence of primordial deuterium is a major problem for steady state since it cannot be produced by other means.
Nanook replies:
The current generation of infrared telescopes are showing us an early population of stars, galaxies, and galactic clusters that look very much like todays stars, galaxies, and galactic clusters.
GD: Yes the mature morphology has been a surprise and galaxy formation models will need to be developed. We know dark matter plays a vital role and we don’t know its nature so there is a big unknown there.
N: Further, if the big bang hypothesis is correct, these massive stars wouldn’t have the Carbon-Nitrogen-Oxygen catalytic fusion cycle available to fuse hydrogen into helium and would have to rely solely on p-to-p chain reactions, which are not normally the dominant reaction in massive stars. Therefore, those stars would not have burned their hydrogen as fast as their mass otherwise would indicate.
GD: You are missing two important points, stars without metals cannot efficiently lose heat by radiation and the were created ina a much denser universe. The net result is that the early stars would have been much bigger and also burned hotter as gravitational collapse would proceed until the p-p reaction could procede.
N: But as it happens we can see carbon monoxide in the very earliest stars, and if carbon was present, the CNO cycle would have been operating but that is inconsistant with the big bang hypothesis.
GD: No, only with the timescale estimated for Pop III stars, it has no consequence for the big bang at all.
N: With regards to metallicy between population II and population III stars, you are using circular logic.
You are assuming that differences in metallicy are due to the stars being 2nd or 3rd generation stars when in fact other explanations exist. Metallicy is highest in stars in the galactic core and lowest in the outer reaches of the galaxy. Stars forming first in the core is one possible explanation, but gravitational stratification is another. That is to say, that as the cloud of hydrogen and heavier elements contracted enough for star formation to begin, the heavier elements were naturally drawn to the center of gravity.
GD: Gravity affect different masses with equal acceleration so that doesn’t hold water. Nor could metals be extracted from rim stars after they formed.
George Dishman writes:
The big bang says the universe is probably infinite in size, or at least 1000 times larger than we can observe. The WMAP results strongly suggest a ‘flat’ (or Euclidean) geometry for the universe which would be infinite in size.
Nanook Replies:
If the big bang is correct expansion happens at a subinfinite speed. It is not possible to have an infinite universe come disperse from a single point in finite time.
GD: True, but who said it came from a finite point? Again you are inventing your own theory. Conventional theory says the universe has always been infinite in spatial extent.
N: And if an infinite universe exists for infinite time, that is the very definition of a steady state universe.
True, but current theory says it had a start 13.7 billion years ago and it was spatially infinite when it started and if it is infinitely old, why are all the globular clusters 12 billion years old, why are there no older white dwarfs and so on. You are conveniently neglecting a huge amount of data that leaves no workable alternative to expansion.
Maybe someone will come up with something new in the future but steady state isn’t it.
George
[Nanook asked:]
“What caused the big bang? What caused inflation?
GD: We don’t know, and that is the essence of science, we observe the universe and learn what observation tells us, but where we cannot answer a question, we admit that.
Nanook Replies:
I don’t think mainstream science does admit it. …
GD: I was just surfing around and came across this:
http://www.openquestions.com/oq-cosmo.htm#questions
That’s just one guy’s idea of “open questions” but it gives you a flavour of where we are.
This also gives a timeline and if you read it you will see many areas where he admit we don’t have models.
http://www.scienceandreason.net/oq/oq-co008.htm#history
George