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A dialogue between Mr. Big Bang and Mr. Steady State
__________________________________________________ __ (Please read first the NASA press release and summary of results at the end of the dialogue.) Mr. Bang: In an eternal, steady state universe there is no evolution. Galaxies would be infinitely evolved, so would life. Big Bang or not we have abundant observational evidence that the universe is changing over time, evolving from chaos to structure. the build up of large scale structure of galaxy superclusters, the origin of the heavier elements, the assembly of galaxies are all consistent with direct observational evidence for this conclusion. To prove otherwise one would have to throw out at lease three decades worth of astronomical observations by the world's most powerful telescopes, and find alternative interpretations for thousands of peer-reviewed scientific papers on cosmology. NASA's W-MAP satellite builds upon this robust and consistent evidence to independently verify the universe is expanding and evolving from state where it was once dense and hot. this does not "prove" there was a big bang, but the expansion of space, and the evolution of galaxies is incontrovertible and based on direct observations, not just theory. This doesn't mean everything is absolutely right. And, if evidence comes up that contradicts the big bang cosmology, astronomers will embrace it as an exciting new intellectual challenge to theory. Mr. State: A great number of spiral galaxies should have halos with globular clusters as old as M4 (12 to 13 billion years). A galaxy situated at, for instance, 8 billion light-years from us is seen at it was 8 billion years ago. Thus, stars from its halo are theoretically 20-21 billion years old. How can this be compatible with an universe which is only 13.7 +/- 0.2 billion years old, according to the BB theory? Doesn't the discrepancy between the age of an expanding universe and that of stars it contains constitute an irrefutable evidence? It is difficult to abandon a 80 year's old paradigm, but this should not prevent the NASA specialists from analysing their wonderful findings in terms of the expanding *and* the "static" universe theories. Mr. Bang: Globulars formed 13 GY ago and the galactic disk about 7 GY ago as part of the hierchical growth of galaxies So? Also, oldest stars are measured to be 13 GY old, no more. There simply is no discrepency whasoever, everything is consistent chronologically. Cosmic expansion aside, the universe looked fundamentally different in the past than it does today. this cannot happen in a steady state cosmology. Mr. State: You are right about M4, which is very close to the Earth. But if a galaxy is situated at, for instance, 8 billion light-years away, its light takes about 8 GY to reach us. In other words, we see that galaxy as it was 8 billion years ago. Its globular clusters, if present, thus formed 8+13 = 21 GY ago. Mr. Bang: The age of the globular clusters in a 8 billion-year distant galaxy would be 13GY - 8GY = 5 GY. Mr. State: Imagine that you find to-day in your attic a photo of your grand grand father, taken 40 years ago. Iow, you see to-day, on the photo, your grand grand father as he was 40 years ago. On the photo, he is 50 years old. Are you claiming that he was born 50Y - 40Y = 10Y ago? Of course, he was born 50 + 40 = 90 years ago! Now let's go back to the galaxy. You see it to-day as it was 8 GY ago. You know that 8 GY ago, it was 13 GY old. Thus, the galaxy was born 13GY + 8Gy = 21 GY ago. Mr. Bang: The information about how my grandfather looked at age 10, was delayed by 40 years until I found the scrapbook. Information from the distant universe is similarly delayed. 50y (grandfather age) - 40yr (information delay time) = 10yr (age in picture) Distance has nothing to do with this. If M4 were halfway across the universe it would still be the same age. A globular cluster 13 billion years away would be seen as a newborn object. The age of the universe is very solid. There are no paradoxes. The local globular cluster are the age of the universe, and anyone living in another galaxy would reach the same conclusion about their own globular clusters. The age of the universe is well-established and supported by numerous lines of observational evidence. Mr. State: You don't see a newborn globular cluster, you take to-day the photo of a galaxy, which is supposed to be surrounded by globular clusters. If the galaxy is 8G light-years away from you, its light took 8 GY to reach you. You know that its globular clusters are 13GY old. Hence, they were born 21 GY ago. This is not a paradox, it is simply logic. I said that you found a photo, taken 40 years ago, of your grand grand father who was 50 when the photo was taken. Iow, his age in picture is 50 yr, not 10 yr. The only valid conclusion is that he was born 90 years ago. If you arrive at another conclusion, you don't think logically. You should use a mental trick to determine when galaxies were born: Instead of saying "This galaxy is e.g. 8 G light-years away", imagine that its photo was taken 8 GY ago (without bothering about the redshift, it could be due to some ageing of the picture). If the galaxy looks on the photo as if it were likely to be surrounded by a halo of globular clusters having an age of 13 GY, you should infer that the galaxy was born 21 GY ago. Mr. Bang: The clusters in that galaxy would have an age of 5 GY, they co-evolve with the galaxy. Very simple, no paradox. This simply is not an issue in cosmology at all. the age of the universe is well-established and suported by numerous lines of observational evidence. If the universe were steady-state we would have no evidence for the origin of structure, the periodic table, or the hierchical grown of galaxies. the past would look exactly the same as the present, and that would be true for the infinite future too. Mr. State: Don't you realize that a galaxy situated at 8 GLY is seen as it was 8 GY ago? Iow, 8 GY ago, such galaxy was already (supposedly) as old as our own galaxy. Or you are claiming that its clusters would have an age of only 5 GY. Iow, the galaxy would be older than its clusters, in plain contradiction with what was rightly claimed in the NASA press release of April 24, 2002: "Globular clusters are the first pioneer settlers of the Milky Way. Many coalesced to build the hub of our galaxy and formed billions of years before the appearance of the Milky Way's magnificent pinwheel disk (as further confirmed by Richer's observations)." Since globular clusters are "the first pioneer settlers of our galaxy", they should be the first settlers of all other comparable galaxies, and also formed billion of years before their appearance. Your position is really untenable. Simple arithmetic and logic should tell you a galaxy already existing 8 GY ago was likely born (or rather its clusters) 21 GY ago. Mr. Bang: Please read the press release. It explains why globular clusters set the age of the universe at 13 GY, if the universe were infinitely old there would be "black dwarf" stars. which simply don't exist. Mr. State: How do you know that "black", or rather very very faint, dwarf stars don't exist? According to the press release, "The ancient white dwarf stars, as seen by Hubble, turn out to be 12 to 13 billion years old. As white dwarfs cool they grow fainter, and this required that Hubble take many snapshots of the ancient globular star cluster M4. The observations amounted to nearly eight days of exposure time over a 67-day period. This allowed for even fainter dwarfs to become visible, until at last the coolest and oldest dwarfs were seen. These stars are so feeble (at 30th magnitude which is considerably fainter than originally anticipated for any Hubble telescope imaging with the original cameras), they are less than one-billionth the apparent brightness of the faintest stars that can be seen by the naked eye." Hubble could hopefully "see" dwarfs of magnitude greater than 30 by increasing the observation period. Anyhow, logic tells that a galaxy comparable to our spiral galaxy, whose dwarf stars supposedly "formed 12 to 13 GY ago", should be older that the BB universe, born 13.7 +/- 0.2 GY ago, if its distance from us were greater than about 2 billion light-years. ****** A question to everybody: _______________________ Who is likely to be right, Mr. Bang or Mr. State? Thanks, Marcel Luttgens ****** Hubble Uncovers Oldest "Clocks" in Space to Read Age of Universe -------------------------------------------------------------------------------- Full press release text: Pushing the limits of its powerful vision, NASA's Hubble Space Telescope has uncovered the oldest burned-out stars in our Milky Way Galaxy. These extremely old, dim "clockwork stars" provide a completely independent reading on the age of the universe without relying on measurements of the expansion of the universe. The ancient white dwarf stars, as seen by Hubble, turn out to be 12 to 13 billion years old. Because earlier Hubble observations show that the first stars formed less than 1 billion years after the universe's birth in the big bang, finding the oldest stars puts astronomers well within arm's reach of calculating the absolute age of the universe. Though previous Hubble research sets the age of the universe at 13 to 14 billion years based on the rate of expansion of space, the universe's birthday is such a fundamental and profound value that astronomers have long sought other age-dating techniques to cross-check their conclusions. "This new observation short-circuits getting to the age question, and offers a completely independent way of pinning down that value," says Harvey Richer of the University of British Columbia, Canada. The new age-dating observations were done by Richer and colleagues by using Hubble to go hunting for elusive ancient stars hidden inside a globular star cluster located 5,600 light-years away in the constellation Scorpius. The results are to be published in the Astrophysical Journal Letters. Conceptually, the new age-dating observation is as elegantly simple as estimating how long ago a campfire was burning by measuring the temperature of the smoldering coals. For Hubble, the "coals" are white dwarf stars, the burned out remnants of the earliest stars that formed in our galaxy. Hot, dense spheres of carbon "ash" left behind by the long-dead star's nuclear furnace, white dwarfs cool down at a predictable rate the older the dwarf, the cooler it is, making it a perfect "clock" that has been ticking for almost as long as the universe has existed. This approach has been recognized as more reliable than age-dating the oldest stars still burning by nuclear fusion, which relies on complex models and calculations about how a star burns its nuclear fuel and ages. White dwarfs are easier to age-date because they are simply cooling, but the trick has always been finding the dimmest and hence longest-running "clocks." As white dwarfs cool they grow fainter, and this required that Hubble take many snapshots of the ancient globular star cluster M4. The observations amounted to nearly eight days of exposure time over a 67-day period. This allowed for even fainter dwarfs to become visible, until at last the coolest and oldest dwarfs were seen. These stars are so feeble (at 30th magnitude which is considerably fainter than originally anticipated for any Hubble telescope imaging with the original cameras), they are less than one-billionth the apparent brightness of the faintest stars that can be seen by the naked eye. Globular clusters are the first pioneer settlers of the Milky Way. Many coalesced to build the hub of our galaxy and formed billions of years before the appearance of the Milky Way's magnificent pinwheel disk (as further confirmed by Richer's observations). Today 150 globular clusters survive in the galactic halo. The globular cluster M4 was selected because it is the nearest to Earth, so the intrinsically feeblest white dwarfs are still apparently bright enough to be picked out by Hubble. In 1928, Edwin Hubble's measurements of galaxies made him realize that the universe was uniformly expanding, which meant the universe had a finite age that could be estimated by mathematically "running the expansion backward." Edwin Hubble first estimated the universe was only 2 billion years old. Uncertainties over the true expansion rate led to a spirited debate in the late 1970s, with estimates ranging from 8 billion to 18 billion years. Estimates of the ages of the oldest normal "main-sequence" stars were at odds with the lower value, since stars could not be older than the universe itself. In 1997 Hubble astronomers broke this impasse by triumphantly announcing a reliable age for the universe, calculated from a very precise measurement of the expansion rate. The picture soon got more complicated when astronomers using Hubble and ground-based observatories discovered the universe was not expanding at a constant rate, but accelerating due to an unknown repulsive force termed "dark energy." When dark energy is factored into the universe's expansion history, astronomers arrive at an age for the universe of 13-14 billion years. This age is now independently verified by the ages of the "clockwork" white dwarfs measured by Hubble. Release Date: 1:00PM (EDT) April 24, 2002 Release Number: STScI-2002-10 Find more Releases at http://hubblesite.org/newscenter/archive/2002/10/ About Star Cluster Globular About Star White Dwarf About Cosmology Universe: Age/Size Summary of results: __________________ The universe is dominated by dark energy (73%). The dark matter is most of the rest (22.4%), and the ordinary stuff we know (all the elements on the periodic table) comprises only 4.4%. About 96% of the universe is unknown stuff. Also, the results indicate an epoch of ionizing radiation around redshift 20 (about 180 million years after the big bang). This ionizing radiation presumably comes from the first stars in the universe, which previously were thought to come from about 800 million years after the big bang. So star formation is earlier than expected, Hubble will not be able to see it (too far into the infrared), and NGST has a new observational motivation. A new map of the cosmic microwave background covering the entire sky confirms COBE results and provides 30 times more resolution. And provides detailed power spectrum of fluctuations in CMB in five different wavelengths. The power spectrum of the CMB fluctutations combined with other results yields a precise 'best fit' cosmology. Age of universe = 13.7 +/- 0.2 billion years Hubble parameter = 71 +/- 4 km/s/Mpc Total mass-energy density parameter, Omega_total = 1.02 +/- 0.02 Dark energy density parameter, Omega_lambda = 0.73 +/- 0.04 Dark matter density parameter, Omega_dark = 0.224 +/- 0.009 Baryon density parameter, Omega_baryon = 0.044 +/- 0.004 Redshift at decoupling (CMB release) = 1089 +/- 1 Age of universe at decoupling = 379,000 +/- 8000 years ****** |
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I am not sure if it is a language thing or what, but during your "dialogue" you
seemed to switch gears, especially during the discussion of the image of the great grand father (grand grand father in your discussion) - suddenly a picture of a 50 year old man taken 40 years ago implied the man was 10 in the photograph, the photograph of a 50 year-old man. But, my initial response to Mr. Steady State in regards to his misinterpretation of images made of distant galaxies and their surrounding clusters would be that if the object was 8 billion lightyears away, then the light we gather is of that galaxy 8 billion years ago. Today, it, along with the rest of the universe might be 13.5 to 13.7 billion years, but we are looking into the past the father we look away so the light we gather is that emitted in the past, not today. The same is true of the photograph. It is a photograph of a 50 year old man. I find it 40 years later. If the old man is still alive, he would be 90 today. That photograph, just like the light we receive from a distant galaxy, preserves the impression of the time it came into existence. It can only tell us the conditions of that time, not the present. So, just like the photograph tells us the condition of the old man back 40 years ago, the light we receive tells us the conditions of that galaxy as it was 8 billion years ago. It, and the universe, have aged and changed in that succeeding time, but we won't know how that change effects appearance of that galaxy for another 8 billion years when the light emitted today has the time to finally reach us (actually, in an expanding, and even potentially accelerating, expanding universe, it might take a bit longer, but the point is the same). |
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![]() "Marcel Luttgens" wrote in message om... A dialogue between Mr. Big Bang and Mr. Steady State __________________________________________________ __ (Please read first the NASA press release and summary of results at the end of the dialogue.) Mr. Bang: In an eternal, steady state universe there is no evolution. Galaxies would be infinitely evolved, so would life. Big Bang or not we have abundant observational evidence that the universe is changing over time, evolving from chaos to structure. the build up of large scale structure of galaxy superclusters, the origin of the heavier elements, the assembly of galaxies are all consistent with direct observational evidence for this conclusion. To prove otherwise one would have to throw out at lease three decades worth of astronomical observations by the world's most powerful telescopes, and find alternative interpretations for thousands of peer-reviewed scientific papers on cosmology. NASA's W-MAP satellite builds upon this robust and consistent evidence to independently verify the universe is expanding and evolving from state where it was once dense and hot. this does not "prove" there was a big bang, but the expansion of space, and the evolution of galaxies is incontrovertible and based on direct observations, not just theory. This doesn't mean everything is absolutely right. And, if evidence comes up that contradicts the big bang cosmology, astronomers will embrace it as an exciting new intellectual challenge to theory. Mr. State: A great number of spiral galaxies should have halos with globular clusters as old as M4 (12 to 13 billion years). A galaxy situated at, for instance, 8 billion light-years from us is seen at it was 8 billion years ago. Thus, stars from its halo are theoretically 20-21 billion years old. How can this be compatible with an universe which is only 13.7 +/- 0.2 billion years old, according to the BB theory? Are you saying that globlar clusters around the most distant galaxies are seen as identical to M4? Alternatively, are you saying that globular clusters don't evolve? |
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"OG" wrote in message ...
"Marcel Luttgens" wrote in message om... You wrote: Are you saying that globlar clusters around the most distant galaxies are seen as identical to M4? Mr. State claimed that a distant galaxy, whose light was emitted 8 GY ago, is seen by us as it was 8 GY ago. If the image of that galaxy looks like that of a spiral galaxy analogous to ours, he inferred that the distant galaxy, 8 GY ago, should also have in its halo stars which are 13 GY old. Hence, the distant galaxy (or rather its halo) was already 13 GY old 8 GY ago, so the stars of its halo were born 21 GY ago. Alternatively, are you saying that globular clusters don't evolve? No, Mr. State didn't make such claim, on the contrary. But, according to Mr. Bang, "A globular cluster 13 billion years away would be seen as a newborn object." Thanks, Marcel Luttgens |
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