In reply to AmericanGypsie for the comment given several posts ago:
Grey dust has been eliminated by the observation of the magnitude/redshift relation for very distant SNe Ia supernovae. Their spectra, brightness and redshifts are all concordant with calculated great distances.
Interstellar gas will not cause redshifts unless it is ionized, like a plasma. But, the existence of a plasma would eminate from all distances so that the distribution of locations of plasma emmision sources would not match the observed emmision source locations. And, the CMB power law (a type of frequency distribution) across the sky and across the spectrum, would not match the observed CMB (you know, that pretty sky chart showing the red and blue patches got from the WMAP satellite).
The disparity between the radius, radius of curvature or Hubble radius derived from H naught and the the magnitude of the scale factor got from application of the Friedmann equations is very large. This lack of agreement stems from the fact that the Friedmann equations calculate the scale factor of the entire universe, not just the "observable" universe.
The inverse of H naught gives the Hubble radius or the approximate size of the observable universe (U). There are other ways to calculate this dimension depending on the type of observation that is made. But, they are in good agreement. For instance, the size of U is a bit smaller because the value of H naught that is obtained for X-rays by the Chandra X-Ray Observatory is a bit larger (77 km/s/Mpc) than the value for H naught got from ancient SNe Ia (72 km/s/Mpc). Brightness measurements alone indicated the universe is very large and very old.
X-ray redshifts will be very different from microwave redshifts and would occur by different mechanisms if it was caused by interferences and not by virgin emmision from the the time of "recombination" after the Big Bang.
It's funny that you suggest scientists may be Christians in disguise. They are mostly atheists or agnostics.
The Plasma panacea that has been proposed to account for everything is being pushed by Fundamentalist Christians as indicating that U is much younger, say, about 6,000 years old. They want to debunk the Big Bang and all it entails because it indicates age in the billions of years.
They will never succeed and they should give up.
Your comments are very good and I appreciate the thought that you have obviously given to this issue. If only certain scientists would give it the same.
However, I surely would not call general or special relativity mere scientific popularism. The Principles of Relativity are the second best validated pillars of all science.
The first best validated Principles are those regarding quantum mechanics and particle physics' quantum chromodynamics (the God Particle type of a merger between quantum science and relativity).
Because popular books have been written does not mean that they have no serious basis just because they are popular.
Showing posts with label redshift. Show all posts
Showing posts with label redshift. Show all posts
Monday, June 21, 2010
Monday, April 30, 2007
Dark Energy Debunked Some More
Re: Dark Energy Debunked
There is always some emotional component in our effort to think. Humans are never perfectly logical. When we unconsciously perceive that a concept may be beyond comprehension, we cough it up, like a snake that has swallowed an oversize egg. And we recoil from it.
The visceral reaction against it is like a reflex that protects our emotional hearts from choking.This business about dark energy and dark matter involves concepts of immense numbers, "curved" space and such long periods of time that we cannot fully comprehend them.
It is what the author meant when he complained of people's incurable "innumeracy". We do not and can not fully acknowledge how ignorant we are of the ultimate implications of the enormously large or incredibly small aspects of reality. It makes me uncomfortable too.
But, at the same time, I experience a fascinating addiction to it! This is why I bother with this blog in the first place.
It is said that even if all the dark matter in the universe is accounted for, there would still not be enough matter and/or energy in the universe to "close" it. I guess that astrophysicists can apply statistical analysis to the pattern found in the cosmic microwave background to extract a mathematical "power law" that describes the distribution of high and low intensity areas in the sky. That power law is consistent with the pattern's being projected onto the sky from a flat source, I think.
This means that space is flat to within a very small percentage. So, the universe is, in fact, closed or at least it is poised delicately on the borderline between open, or ever expanding, and completely closed, eventually to contract.
But very distant type 1a supernovae SEEM to be more distant, by luminosity measurements, than they SEEM to be by redshift measurements. So, the universe should be older by luminosity than it is by redshift.
If one extrapolates redshift versus distance or time back toward zero, one obtains an intersection with the ordinate axis that is short of the origin (as determined by luminosity). The only way that this could occur is if the radial velocity of expansion line is curved upward, is concave rather than convex. This is the same as saying the universe expansion rate is accelerating.
But, then it is not closed or poised on the borderline. If it is poised, it would show a leveling off, an asymptotic approach to a plateau. So CMB data show a picture that is at odds with the supernova data.
It is not all consistent, in other words. And the rush to a conclusion is surely premature.
There is much evidence in support of the inflationary model of the evolution of the universe. Alan Guth's inflation says that the universe should have a flat curvature to within an exceedingly small percentage. But, again, an accelerating universe is not flat.
Cosmologists seem to want to have it both ways and the alternatives are mutually contradictory. And, they insist on referring to a Hubble CONSTANT. If the universe is doing anything but expanding at a constant rate, if it is slowing down or speeding up, we have a Hubble parameter, not a constant. And then one cannot use linear regression analysis to determine H naught.
That the the latter point is missed may be due to sloppy journalism. The way these issues are discussed in the popular press is confusing. When journalists do not know that an overturned tanker of liquid nitrogen cannot explode like liquid hydrogen or promote an exposion like liquid oxygen, we cannot trust their scientific judgement.
Your visceral reaction against all of this is just a reaction to reality. It is all really very disgusting! Let us continue to watch the soap opera. Maybe there will be some kind of conclusion after all.
Gary Kent
There is always some emotional component in our effort to think. Humans are never perfectly logical. When we unconsciously perceive that a concept may be beyond comprehension, we cough it up, like a snake that has swallowed an oversize egg. And we recoil from it.
The visceral reaction against it is like a reflex that protects our emotional hearts from choking.This business about dark energy and dark matter involves concepts of immense numbers, "curved" space and such long periods of time that we cannot fully comprehend them.
It is what the author meant when he complained of people's incurable "innumeracy". We do not and can not fully acknowledge how ignorant we are of the ultimate implications of the enormously large or incredibly small aspects of reality. It makes me uncomfortable too.
But, at the same time, I experience a fascinating addiction to it! This is why I bother with this blog in the first place.
It is said that even if all the dark matter in the universe is accounted for, there would still not be enough matter and/or energy in the universe to "close" it. I guess that astrophysicists can apply statistical analysis to the pattern found in the cosmic microwave background to extract a mathematical "power law" that describes the distribution of high and low intensity areas in the sky. That power law is consistent with the pattern's being projected onto the sky from a flat source, I think.
This means that space is flat to within a very small percentage. So, the universe is, in fact, closed or at least it is poised delicately on the borderline between open, or ever expanding, and completely closed, eventually to contract.
But very distant type 1a supernovae SEEM to be more distant, by luminosity measurements, than they SEEM to be by redshift measurements. So, the universe should be older by luminosity than it is by redshift.
If one extrapolates redshift versus distance or time back toward zero, one obtains an intersection with the ordinate axis that is short of the origin (as determined by luminosity). The only way that this could occur is if the radial velocity of expansion line is curved upward, is concave rather than convex. This is the same as saying the universe expansion rate is accelerating.
But, then it is not closed or poised on the borderline. If it is poised, it would show a leveling off, an asymptotic approach to a plateau. So CMB data show a picture that is at odds with the supernova data.
It is not all consistent, in other words. And the rush to a conclusion is surely premature.
There is much evidence in support of the inflationary model of the evolution of the universe. Alan Guth's inflation says that the universe should have a flat curvature to within an exceedingly small percentage. But, again, an accelerating universe is not flat.
Cosmologists seem to want to have it both ways and the alternatives are mutually contradictory. And, they insist on referring to a Hubble CONSTANT. If the universe is doing anything but expanding at a constant rate, if it is slowing down or speeding up, we have a Hubble parameter, not a constant. And then one cannot use linear regression analysis to determine H naught.
That the the latter point is missed may be due to sloppy journalism. The way these issues are discussed in the popular press is confusing. When journalists do not know that an overturned tanker of liquid nitrogen cannot explode like liquid hydrogen or promote an exposion like liquid oxygen, we cannot trust their scientific judgement.
Your visceral reaction against all of this is just a reaction to reality. It is all really very disgusting! Let us continue to watch the soap opera. Maybe there will be some kind of conclusion after all.
Gary Kent
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