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Universe is older than the big bang
In article , "jacob navia"
wrote: The current age of the "universe since the big bang" is around 13 700 million years. An italian researcher has discovered that some nuclear reactions inside stars are twice as slow as previously assumed, making the universe 1 000 million years older, i.e. 14 700 million years. Conclusion: the universe is older than the big bang? :-) Of course not. Big bang "theory" will adapt itself to the new data, some parameters will be tweaked and we will continue as before as nothing has ever happened. Big bang theory is indestructible as it seems. Actually, the process is similar to that when one realized that the sun could not be supported by chemical reactions, and the nuclear process where discovered as an explanation, giving a lifespan of a few billion years. Indirect evidence of this was found because of geological and paleontological evidence on the planet earth itself. I have suggested here, before, that similar things may happen with the Big Bang theory as more detailed information about the universe and what is in it is found. One will then successively adjust the age of the universe upwards, as this new evidence is found. The quoted article, if correct, would correspond in the historical example above to indirect, paleontological evidence on the earth, giving hints that the sun must be much older. Hans Aberg |
#3
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Universe is older than the big bang
"jacob navia" wrote in message ...
The current age of the "universe since the big bang" is around 13 700 million years. An italian researcher has discovered that some nuclear reactions inside stars are twice as slow as previously assumed, making the universe 1 000 million years older, i.e. 14 700 million years. The 13,700 million year number comes from the first year WMAP results and was never even close to their +/- 200 million year "error". The correct age for the universe is 15,556 million years (+/- 24 million) based on the most accurate CMB temperature measurement. This new result from radioactive decay implies that the universe is at least 14,700 million years. So the 15,556 million year result looks pretty compelling at this point. |
#4
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Universe is older than the big bang
There are other lines of evidence that point in the
same direction of a much older universe: quasars containing iron at 13 billion light years, and (for me) the shape of the galaxy. Assuming a more or less spherical initial rotating gas cloud, this flat shape needs more than 100 revolutions to get so flat. Just a "gut feeling" of course. [Mod. note: on s.a.r. we prefer actual calculations to `gut feelings'. `gut feelings' not based on physics are likely to fall foul of the speculativeness criterion -- mjh] |
#5
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Universe is older than the big bang
jacob navia wrote:
The current age of the "universe since the big bang" is around 13 700 million years. An italian researcher has discovered that some nuclear reactions inside stars are twice as slow as previously assumed, making the universe 1 000 million years older, i.e. 14 700 million years. No, this is not what the article is saying. It says that the oldest starts should be one billion years older than previously thought, but I have my reservations about this, as I state below. Conclusion: the universe is older than the big bang? :-) Of course not. Big bang "theory" will adapt itself to the new data, some parameters will be tweaked and we will continue as before as nothing has ever happened. Big bang theory is indestructible as it seems. Here is a citation of the announcemnt (appeared in sci.space.news) ---------------------------------------------------------------------------- --- Istituto Nazionale di Fisica Nucleare Rome, Italy Contact: Carlo Broggini, , 349 157 44 14 2004 May 13 The Universe, seen under the Gran Sasso mountain, seems to be older than expected Some nuclear fusion reactions inside stars occur more slowly than we thought and, as a consequence, stars themselves, as well as galaxies and the entire universe are a bit older than expected. This is what comes out from the last results of Luna experiment (Laboratory for Underground Nuclear astrophysics), settled by National Laboratories of Gran Sasso and realized in cooperation by Infn and Ruhr University in Bochum (Germany). The study, that will be published on the review Physics Letters B next June 17, has been published today on the website of the review. A second article has been accepted by the review Astronomy and Astrophysics. Luna's aim is the production of some reactions that occur inside stars, in particular in the Sun, and the measure of their velocity. In Luna, protons (which means hydrogen nuclei) are made collide against nitrogen nuclei: a reaction that leads to the formation of an oxygen nucleus with the contemporary emission of energy. "The great part of the energy emitted by our star derives from fusion reactions of four hydrogen nuclei that lead directly to the formation of a helium nucleus. But there is another process in consequence of that helium nuclei are produced and this process passes through the so-called carbon-nitrogen-oxygen cycle. Cycle velocity is determined by the slowest of the reactions that form it, the one that leads to an oxygen nucleus as a result of the fusion between an azote nucleus and a proton. That is to say the reaction studied by Luna," explains Carlo Broggini, Luna coordinator. Producing fusion between the nitrogen nucleus and a proton is not difficult itself, but a difficulty lies in obtaining it at the same energy it occurs in stars: a relatively low energy, thanks to which the phenomena is quite slow, corresponding to a very few reactions a day (a lucky case for our planet, because if these phenomena occurred rapidly, the Sun would have burned up its 'fuel' in a few time and this would have made life -- as we know it -- impossible). "In an ordinary laboratory settled on surface, the effects of the reaction studied by Luna would be totally hidden by similar, but much more abundant effects due to reactions caused by the cosmic rays rain that crashes into our planet without interruption. The Gran Sasso Laboratories are on the contrary located under 1,400 meters of rocks, which constitute an impenetrable barrier for almost all the particles coming from Space. Thanks to these particular conditions we could carry out our experiment," says Carlo Broggini. The result has been surprising: the carbon-nitrogen-oxygen cycle occurs two times more slowly than expected. "The most fascinating aspect of this study is that another estimate of Universe age flows from it. Actually, the age of the most ancient stars, those that form the so-called globular star clusters, is calculated on the base of the light spectra they emit, supposing we know the carbon-nitrogen-oxygen cycle's velocity. As this last one seems to be slower than previewed, the age of the globular star clusters' has also been newly calculated and grown-up of about one billion years. As a consequence, in the light of Luna's new data, the age of our Universe passes from the previous estimate of about 13 billions years to that of about 14 billions years," explains Eugenio Coccia, director of Gran Sasso National Laboratories. A star that lives to get as old as 13 billion years, will not be any heavier than the Sun, and for that reason most of its energy will be produced by the proton-proton-chain. Therefore I cannot see that a change in the cross sections for the CNO-cycle would have a major influence on their age. By the way, are the current age estimates for the oldest globular clusters stars really as high as 13 billion years? Luna's results offer also another information: neutrinos provided with high energy produced by carbon-nitrogen-oxygen cycle are the half part of what expected, because this last one is responsible of only the 0.8% of the energy emitted by the Sun (and not the 1.6%, as believed). This data is of great interest for astroparticles physicists engaged in experiments that are specifically focused on neutrinos of relatively high energy, as it is for example the experiment Borexino, which is in preparation at Gran Sasso National Laboratories, or the Japanese Kamland. This is definitely not right. The solar neutrinos that are observed are produced in some side branches of the p-p-chain, and since the neutrino oscillations were discovered there is good agreement between the observed and the calculated neutrino fluxes from the Sun. Ulf Torkelsson |
#6
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Universe is older than the big bang
Hans Aberg wrote:
[text snipped] I have suggested here, before, that similar things may happen with the Big Bang theory as more detailed information about the universe and what is in it is found. One will then successively adjust the age of the universe upwards, as this new evidence is found. Historically, this is not what has happened in the last few decades. Ten years ago there were two schools that concluded that the universe was 10 billion years old, and 18 to 20 billion years old. Since then the measurements of the expansion rate of the universe has improved, and the current best estimate is that it is 13.7 billion years old give or take a few hundred million years. Actually what has happened is that the error bars have been shrinking drastically, and people are converging to one set of cosmological parameters. Ulf Torkelsson |
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