petrushka.googol Posted September 20, 2015 Posted September 20, 2015 As we are all aware neutrinos have been emitted from the big bang (approx 13.7 billion years ago). Does aging impact these neutrinos? Will they decay or lose momentum ? Will there be any artifacts from the big bang after another 13 billion years ?
Mordred Posted September 21, 2015 Posted September 21, 2015 Aging isn't a good descriptive. Yes neutrinos do decay. Though their mean lifetime varies. http://ned.ipac.caltech.edu/level5/Bowyer/Bowyer6_1.html not sure what your referring to by artifacts of creation. Figuratively speaking everything we see and measure today is a result of the beginning. Albeit in different states.
petrushka.googol Posted September 21, 2015 Author Posted September 21, 2015 Aging isn't a good descriptive. Yes neutrinos do decay. Though their mean lifetime varies. http://ned.ipac.caltech.edu/level5/Bowyer/Bowyer6_1.html not sure what your referring to by artifacts of creation. Figuratively speaking everything we see and measure today is a result of the beginning. Albeit in different states. Then "neutrino dating" similar to radio carbon dating cannot be used to reverse engineer the early state of the Universe. But then neutrinos are ubiquitous.....
Mordred Posted September 21, 2015 Posted September 21, 2015 That doesn't mean we can't determine the age of the universe. You determine the universe age by understanding the universe expansion history.
mathematic Posted September 21, 2015 Posted September 21, 2015 Neutrinoes don't decay in the usual sense. What happens is they change from one variety to another, so that no matter how they are created, they eventually end up as a mix of the three kinds (tauon, muon, electron).
Mordred Posted September 22, 2015 Posted September 22, 2015 (edited) to expand on Mathematic's response. Particle decay is the spontaneous process of one elementary particle transforming into other elementary particles. During this process, an elementary particle becomes a different particle with less mass and an intermediate particle such as W boson in muon decay. Edited September 22, 2015 by Mordred
Strange Posted September 23, 2015 Posted September 23, 2015 (edited) As we are all aware neutrinos have been emitted from the big bang (approx 13.7 billion years ago). Does aging impact these neutrinos? Will they decay or lose momentum ? Will there be any artifacts from the big bang after another 13 billion years ? In the same way that there is a cosmic microwave background (CMB), there should be a cosmic neutrino background of low-energy neutrinos released early in the universe. Unfortunately, we cannot detect neutrinos with low energy like that. Which is a shame because they would probably tell us a lot about the early universe (they would have been released about 380,000 years earlier than the CMB). https://en.wikipedia.org/wiki/Cosmic_neutrino_background Edited September 23, 2015 by Strange
mathematic Posted September 24, 2015 Posted September 24, 2015 to expand on Mathematic's response. Particle decay is the spontaneous process of one elementary particle transforming into other elementary particles. During this process, an elementary particle becomes a different particle with less mass and an intermediate particle such as W boson in muon decay. Neutrinoes have far too little mass to undergo the process you described. from Wikipedia: The strongest upper limit on the masses of neutrinos comes from cosmology: the Big Bang model predicts that there is a fixed ratio between the number of neutrinos and the number of photons in the cosmic microwave background. If the total energy of all three types of neutrinos exceeded an average of 50 eV per neutrino, there would be so much mass in the universe that it would collapse.[39] This limit can be circumvented by assuming that the neutrino is unstable; however, there are limits within the Standard Model that make this difficult. A much more stringent constraint comes from a careful analysis of cosmological data, such as the cosmic microwave background radiation, galaxy surveys, and the Lyman-alpha forest. These indicate that the summed masses of the three neutrinos must be less than 0.3 eV.[40]
Mordred Posted September 24, 2015 Posted September 24, 2015 Your missing one key aspect of neutrinos they can decay into other forms of neutrinos. For example muon neutrinos can decay into tau neutrinos. Here http://home.web.cern.ch/about/updates/2015/06/opera-detects-its-fifth-tau-neutrino. Google neutrino oscillations The funny part about neutrino oscillations is an electron neutrino can decay into a muon neutrinos then the muon neutrino into the tau neutrino, but the reverse process is also true. https://en.m.wikipedia.org/wiki/Neutrino_oscillation When it comes to decay its total energy not just rest energy. For example a proton to proton collision produced the heavier Higgs boson by increasing the inertial mass of the two protons. https://en.m.wikipedia.org/wiki/Higgs_boson Another good example is production of top quarks. "Because top quarks are very massive, large amounts of energy are needed to create one. The only way to achieve such high energies is through high energy collisions. These occur naturally in the Earth's upper atmosphere as cosmic rays collide with particles in the air, or can be created in a particle accelerator." https://en.m.wikipedia.org/wiki/Top_quark In both cases proton to proton collions at extremely high energy states produce particles larger than their invariant (rest mass)
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