vanpelt@unisv.UUCP (Mike Van Pelt) (03/22/88)
In article <7831@agate.BERKELEY.EDU> weemba@garnet.berkeley.edu (Obnoxious Math Grad Student) writes: >(1) De Rujula, Weinstein, and others have proposed to use Tev-Pev neutrinos > for doing whole earth tomography. One Earth diameter of rock and iron > should be just the right distance. Earthquake prediction and the like > would surely benefit. This requires SSC-level energies. Their actual > proposals get further out: for maximum tomography benefit, they want to > try floating the SSC out at sea! I posted a short description with > references about a year ago. > Now this is fascinating, and deserves to be split out into a separate subject. It seems to me that what you really need to do for this is to put your SSC in orbit. -- Mike Van Pelt Unisys, Silicon Valley vanpelt%unisv@ubvax Bring back UNIVAC! ...uunet!ubvax!unisv!vanpelt
weemba@garnet.berkeley.edu (Obnoxious Math Grad Student) (03/22/88)
In article <240@unisv.UUCP>, vanpelt@unisv (Mike Van Pelt) writes: >In article <7831@agate.BERKELEY.EDU> weemba@garnet.berkeley.edu (Obnoxious Math Grad Student) writes: >>(1) De Rujula, Weinstein, and others have proposed to use Tev-Pev neutrinos >> for doing whole earth tomography. I'm so embarrassed: that's Weinberg. >Now this is fascinating, and deserves to be split out into a separate >subject. I posted such an article on this last year--someone else can look it up and summarize. It was in Physics Reports 1984 or so. > It seems to me that what you really need to do for this is to >put your SSC in orbit. You got it! And remarkably enough, one of the SSC site proposals submitted was for outer space. Too bad it didn't make it onto the short list. ucbvax!garnet!weemba Matthew P Wiener/Brahms Gang/Berkeley CA 94720
govett@avsd.UUCP (David Govett) (03/23/88)
> In article <7831@agate.BERKELEY.EDU> weemba@garnet.berkeley.edu (Obnoxious Math Grad Student) writes: > >(1) De Rujula, Weinstein, and others have proposed to use Tev-Pev neutrinos > > for doing whole earth tomography. One Earth diameter of rock and iron > > should be just the right distance. Earthquake prediction and the like > > would surely benefit. This requires SSC-level energies. Their actual > > proposals get further out: for maximum tomography benefit, they want to > > try floating the SSC out at sea! I posted a short description with > > references about a year ago. > > > Now this is fascinating, and deserves to be split out into a separate > subject. It seems to me that what you really need to do for this is to > put your SSC in orbit. > -- What would you use to detect neutrinos? Also, what kind of image would you obtain if there were no interaction between the earth and the stream of neutrinos? If a miniature detector could be built, transterran communication would be possible.
kent@xanth.cs.odu.edu (Kent Paul Dolan) (03/23/88)
In article <240@unisv.UUCP> vanpelt%unisv@ubvax.ub.com (Mike Van Pelt) writes: >In article <7831@agate.BERKELEY.EDU> weemba@garnet.berkeley.edu (Obnoxious Math Grad Student) writes: >>(1) De Rujula, Weinstein, and others have proposed to use Tev-Pev neutrinos >> for doing whole earth tomography. One Earth diameter of rock and iron >> should be just the right distance. Earthquake prediction and the like >> would surely benefit. This requires SSC-level energies. Their actual >> proposals get further out: for maximum tomography benefit, they want to >> try floating the SSC out at sea! I posted a short description with >> references about a year ago. >> >Now this is fascinating, and deserves to be split out into a separate >subject. It seems to me that what you really need to do for this is to >put your SSC in orbit. There you go! Build two of whatever you use to launch it, and the spare can launch the next twenty or thirty years of the space program in one fell swoop. Talk about your big, dumb boosters! [Notice the "Followups-to:" line!] Kent, the (Birthright Party's Choice for Chief Somnambulist) man from xanth. "The Birthright of Humankind is the Stars!" +-------------------------------------------------------+ |\~ | | |~ . o o . :;: () -O- 0 . O | | |~ ^ | |/~ | | | You are Here | | | |Wouldn't you rather be out there --> | | | |Support the Birthright Party Today! | | | |(Note: Above diagram NOT to scale.) | +-------------------------------------------------------+ [This lovely banner, available at a terminal near you for a donation of a mere 3 5/7 Quatloos, brought to you through the keyboard talents of Michael P. Seidel, Press Secretary Nominee to the Administration of the Chief Somnambulist Candidate.] Join the KENT FOR PRESIDENT movement in talk.bizarre!
weemba@garnet.berkeley.edu (Obnoxious Math Grad Student) (03/24/88)
In article <53@avsd.UUCP>, govett@avsd (David Govett) writes: >> >(1) De Rujula, Weinstein, and others have proposed Whoops, it's not Weinstein, it's not Weinberg, it's Glashow. >What would you use to detect neutrinos? Would you believe they plan to hear them? >Also, what kind of image would you obtain if there were no interaction >between the earth and the stream of neutrinos? A totally blank picture. Obviously, this is not part of their proposal. ----------------------------------------------------------------------- OK, enough people have e-mailed to me that I'm writing this article on the subject. The reference is A De Rujula, S L Glashow, R R Wilson, G Charpak, "Neutrino Exploration of the Earth", PHYSICS REPORTS, v99, #6 (1983), pp 341-396. While normally that journal is too arcane for all but the professionals, this article is a delightful exception. Anyone who knows elementary physics can read the whole thing, while those who get by on SCIENTIFIC AMERICAN or even ANALOG could read about 1/3 of the article, which consists of general descriptions of their idea. (Un- like the popular literature, they do not take the time to explain basic notions. But if you're interested in the stuff already, you probably won't need them. Indeed, this is why I don't like the popular science literature much anymore--seeing "neutrino" or "prime number" defined for the zillionth time bores me.) One thing that needs to be kept in mind is that the properties of neu- trino that you've been told about before--their ability to penetrate millions of light years of matter without interacting--needs qualifi- cation. The cross section (== interaction probability) of neutrinos increases with energy. Thus, by the time they reach Tev-Pev energies, the earth is only semi-transparent, and significant rates of neutrino interaction will occur. They propose three applications: Projects GENIUS, GEMINI, GEOSCAN. Project GENIUS (Geological Exploration by Neutrino-Induced Underground Sound) is meant to aid searches for deposits of oil and gas. They plan to detect neutrinos by *listening* for them. They estimate that the neu- trino impact will create a small noise about .1% of the background. The rough idea is that careful analysis of this signal as they vary the beam energy will reveal the speed of sound underground, plus give a rough map. Project GEMINI (Geological Exploraton with Muons Induced by Neutrino In- teractions) is meant to detect high-Z ore (= heavy metals), since the rate of muon formation near the surface will be sensitive to atomic number. The detectors for this are special muon trucks. Project GEOSCAN is meant to determine the vertical density profile of the earth, especially the core, as a form of Whole Earth Tomography. They estimate that an appropriate accelerator would cost 1-3 gigadollars. While primarily meant as a research instrument in high-energy physics, by planning ahead they hope to get much more out of it. They view the whole thing as technically feasible but financially impossible; note that this was the pre-SSC view of the matter. I suspect they also plan to get nice tans out it. You see, to maximize the ease of aiming this accelerator, they suggest floating it out at sea. They propose somewhere isolated bay, with calm seas, a coral reef for an- choring the device, etc. They didn't name any islands in particular, but it wasn't hard to guess general locations. ------------------------------------------------------------------------ I should point out things like the above are one of the reasons that so much science fiction leaves me unimpressed. REAL science is so much more mind-blowing. WOW! That theory goes STRAIGHT UP into the CLOUDS! AMAZING!! ucbvax!garnet!weemba Matthew P Wiener/Brahms Gang/Berkeley CA 94720