Meeting last night
I had a last-minute glitch and couldn't make it to the meeting. I really wanted to come, if only to prove I'm not dead yet. Anyone care to give a brief rundown? Thanks much, Michael
Several of us are going to Wolf Creek over Labor Day weekend. Any interest from members of this group? Great meeting last night by U of U professor on theories about dark matter and dark energy. "Normal" matter and energy are only 5 % of the mass of the universe. Dark matter is 25% and dark energy 70%. Dark matter can be explained by the concept of minimal acceleration, which may have been confirmed by the Pioneer spacecraft, now at the outskirts of the solar system. It appears to have a minute amount of additional acceleration that can not be accounted for otherwise. The amount is so small, however, that out-gassing from the spacecraft could have caused it. There are many esoteric theories including multidimensional space that may account for dark energy but so far no proof of any of them. -----Original Message----- From: utah-astronomy-bounces+djcolton=piol.com@mailman.xmission.com [mailto:utah-astronomy-bounces+djcolton=piol.com@mailman.xmission.com] On Behalf Of Michael Carnes Sent: Wednesday, August 24, 2005 7:00 AM To: Utah Utah Astronomy List Subject: [Utah-astronomy] Meeting last night I had a last-minute glitch and couldn't make it to the meeting. I really wanted to come, if only to prove I'm not dead yet. Anyone care to give a brief rundown? Thanks much, Michael _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.utahastronomy.com
Don, I last read a physics text in 1979 at the U, so please excuse me if I'm horribly out of date here, but what about WIMPs or other proposed massive particles? Any research progress there? I had read once, years ago, of speculation that there may be elements with atomic numbers above 200-300 that have remained undiscovered due to non-interaction with elements of lower atomic weight. Also, isn't it even remotely possible that the amount of 'normal' baryonic matter has been grossly underestimated? "Dark baryonic matter"- undetected dust and non-interactive gas, maybe? Or BM beyond the observable limits of the universe? Naive questions from a layman, thanks. --- "Don J. Colton" <djcolton@piol.com> wrote:
There are many esoteric theories including multidimensional space that may account for dark energy but so far no proof of any of them.
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He discussed in some detail all the known particles and eliminated each one in turn. There was some discussion about a particle that emits no energy and is stable. Apparently they are going to try to interact with such a particle, if it exists, using the one of the supercolliders. It would show up by being created from other particles and removing energy from a closed system. He also discussed how the energy of a vacuum state could account for a very small amount of the dark energy. Apparently there is no state (according to quantum mechanics) without at least some energy. -----Original Message----- From: utah-astronomy-bounces+djcolton=piol.com@mailman.xmission.com [mailto:utah-astronomy-bounces+djcolton=piol.com@mailman.xmission.com] On Behalf Of Chuck Hards Sent: Wednesday, August 24, 2005 10:02 AM To: Utah Astronomy Subject: RE: [Utah-astronomy] Wolf Creek and Meeting last night Don, I last read a physics text in 1979 at the U, so please excuse me if I'm horribly out of date here, but what about WIMPs or other proposed massive particles? Any research progress there? I had read once, years ago, of speculation that there may be elements with atomic numbers above 200-300 that have remained undiscovered due to non-interaction with elements of lower atomic weight. Also, isn't it even remotely possible that the amount of 'normal' baryonic matter has been grossly underestimated? "Dark baryonic matter"- undetected dust and non-interactive gas, maybe? Or BM beyond the observable limits of the universe? Naive questions from a layman, thanks. --- "Don J. Colton" <djcolton@piol.com> wrote:
There are many esoteric theories including multidimensional space that may account for dark energy but so far no proof of any of them.
__________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com _______________________________________________ Utah-Astronomy mailing list Utah-Astronomy@mailman.xmission.com http://mailman.xmission.com/cgi-bin/mailman/listinfo/utah-astronomy Visit the Photo Gallery: http://www.utahastronomy.com
Chuck Sorry, I didn't scroll down all the way and get the rest of your comments. He didn't talk about elements with high atomic numbers. He discussed brown dwarfs etc. as a possibility but said numerous surveys using gravitation lensing etc. had failed to convince anyone this was a significant component. He didn't talk about the other possibilities but we ran out of time for questions. The speaker was Dr. Paolo Gondolo of the Physics Department at paolo@physics.utah.edu. His credentials are below: Educational Background: Laurea 1986, Università di Trieste Ph.D. 1991, University of California, Los Angeles Research Interests: Dr. Gondolo works at the interface of cosmology, astrophysics, and high energy physics. His main current interests are the nature of dark matter and dark energy, and high-energy cosmic neutrinos. Selected Recent Publications "DarkSUSY: Computing Supersymmetric Dark Matter Properties Numerically" (with J. Edsjö, P. Ullio, L. Bergström, M. Schelke, E.A. Baltz), Journal of Cosmology and Astroparticle Physics, to appear (2004) [astro-ph/0406204]. "Microlensing Candidates in M87 and the Virgo Cluster with the Hubble Space Telescope" (with E.A. Baltz, T.R. Lauer, D.R. Zurek, M.M. Shara, J. Silk, S.E. Zepf), Astrophysical Journal, to appear (2004) [astro-ph/0310845]. "Introduction to Non-Baryonic Dark Matter", Lectures delivered at the NATO Advanced Study Institute "Frontiers of the Universe", Cargèse, France (2003) [astro-ph/0403064]. "The Effects of the Sagittarius Dwarf Tidal Stream on Dark Matter Detectors" (with K. Freese, H.J. Newberg, M. Lewis) Physical Review Letters 92, 111301 (2004) [astro-ph/0310334]. "Future Type Ia Supernova Data as Tests of Dark Energy from Modified Friedmann Equations" (with Y. Wang, K. Freese, M. Lewis) Astrophysical Journal 594, 25 (2003) [astro-ph/0302064]. "Measuring the prompt atmospheric neutrino flux with down-going muons in neutrino telescopes" (with G. Gelmini and G. Varieschi) Physical Review D67, 017301 (2003) [hep-ph/0209111]. "Recoil momentum spectrum in directional dark matter detectors" Physical Review D66, 103513 (2002) [hep-ph/0209110]. -----Original Message----- From: utah-astronomy-bounces+djcolton=piol.com@mailman.xmission.com [mailto:utah-astronomy-bounces+djcolton=piol.com@mailman.xmission.com] On Behalf Of Chuck Hards Sent: Wednesday, August 24, 2005 10:02 AM To: Utah Astronomy Subject: RE: [Utah-astronomy] Wolf Creek and Meeting last night Don, I last read a physics text in 1979 at the U, so please excuse me if I'm horribly out of date here, but what about WIMPs or other proposed massive particles? Any research progress there? I had read once, years ago, of speculation that there may be elements with atomic numbers above 200-300 that have remained undiscovered due to non-interaction with elements of lower atomic weight. Also, isn't it even remotely possible that the amount of 'normal' baryonic matter has been grossly underestimated? "Dark baryonic matter"- undetected dust and non-interactive gas, maybe? Or BM beyond the observable limits of the universe? Naive questions from a layman, thanks. --- "Don J. Colton" <djcolton@piol.com> wrote:
There are many esoteric theories including multidimensional space that may account for dark energy but so far no proof of any of them.
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Thanks, Don. Although perhaps gravitational lensing techniques would have detected them also, I wonder about black holes in mass-poor regions- those with no accretion disks, and thus no emmisions (other than gravity waves). Or perhaps "small" black holes, those unrelated to stellar evolution? Surely we haven't inventoried all possible large forms of baryonic matter. --- "Don J. Colton" <djcolton@piol.com> wrote:
He didn't talk about elements with high atomic numbers.
He discussed brown dwarfs etc. as a possibility but said numerous surveys using gravitation lensing etc. had failed to convince anyone this was a significant component. He didn't talk about the other possibilities but we ran out of time for questions.
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participants (3)
-
Chuck Hards -
Don J. Colton -
Michael Carnes