S3 Analysis Summary Questions, Answers, Comment and Discussion
11 Sep 2005 17:07:07 UTC
Topic 189872
(moderation:
I have just posted the long-promised first report on the Einstein@Home S3 analysis. Please use this thread for questions, answers, comments and discussion.
Bruce
Director, Einstein@Home
S3 Analysis Summary Questions, Answers, Comment and Discussion
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This is just wonderful! :D I feel like I've gone to heaven! ;)
Now there is a lot of "meat" to this project for me, and that is a bigger incentive than the point system for sticking with it for the long term (although the points are fun to track one's progress on a day-to-day basis, and get a sense of one's contribution to the project, but they are not a great incentive for a long-term commitment to a project).
Thank you so much!
I have no idea what any of it
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I have no idea what any of it means, but I'm happy to help.
Excellent! Above and beyond
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Excellent! Above and beyond the call to duty. Thanks for the marvelous report http://einstein.phys.uwm.edu/PartialS3Results/
The writers(s) have succeeded in a very difficult job of explaining the very technical science and math in "undergraduate" terms. Sharp, brief, ample and to the point, and nothing unnecessary or uninteresting. The pictures, diagrams and text all work together very well. There is a wealth of linked footnotes and deeper technical material.
I liked Ch 2, the brief overview of the way the LIGO instrument works. The essential components of the instrument are illustrated to show how gravitational waves generate the signal that Einstein@Home helps analyze.
Chapters 5 through 14 give a wonderful explanation of the nature of the raw data, signal levels, noise, and limits of detectability. One example: The Earth's rotation and movement around the sun complicate an ordinary FFT analysis of the data. This motion has to be -- and is -- compensated for in the software we use. A side effect is that there are always small areas in the celestial sphere where instrument sensitivity is reduced. (Fortunately, these points are not fixed; they change as the Earth moves and rotates.) There are local noise sources, such as power-grid 60Hz and harmonics that are attended to.
Chapter 9, "How does the Einstein@Home S3 search work?" gets to the meat. Here's part of the first few paragraphs.
Go to the link for more. It's a delight.
Not saying that I undestand
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Not saying that I undestand all what status report includes but great stuff. Definitely worth reading - saying a lot about Einstein@home science, data sets and it's future.
Thanks for the report.
I can't resist quoting this
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I can't resist quoting this fact about the LIGO instrument. The mirrors and beam splitter the end of the arms are 4 km (2.48 miles) apart (see Ch 2). It is the relative movement of the mirror/beam splitter pair that is measured. The sensitivity is proportional to the length divided by how small a movement of the mirror can be detected. We know the length. So how small a motion of the end point can be measured? This from Ch 8 of the Report:
(my emphasis)
Wow!
RE: I have just posted ...
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It's just wonderful when cutting edge science is made so comprehensible.
Physicists usually scare me witless with their "spinors", "twistors", "Lie groups", "complex manifolds", "Hamiltonians", "calculus of variations" and what not.
Simple signal processing is familiar to "the rest of us".
Thanx!
Greetings, Mr. Ragnar Schroder, Bachelor of Science, math major :-) .
Thanks all for such a great
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Thanks all for such a great comprehensive and layman friendly report. It is worth the wait! I hope the S4 run report proves to be even more intresting! Thanks again.....it will help keep the intrest in the project alive and well. Cheers, Rog.
RE: RE: I have just
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There would be no search for gravitational waves without Einstein's General Theory of Relativity, heavily based on tensor calculus. See e.g. Peter G. Bergmann's (a disciple and coworker od Einstein) "The riddle of gravitation" (1968). In 1970 I published an article by Bergmann in the Mondadori's Yearbook of Science and Technology which gave an account of the first attempts to search for gravitational waves made by Joseph Weber at the University of Maryland with instruments far less advanced than those used in quote Einstein "theory teaches us what can be observed".
Phd. Allen & Co-authors - A
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Phd. Allen & Co-authors - A sincere “Thank You” for authoring for what I feel is a highly complicated paper, in terms a layman, such as myself, can mostly comprehend with relative ease. After several readings, I feel I have been educated more than I have over the past month and a-half of searching through and reviewing posted threads and written articles within this site and other web sites. You are truly Master's of diction.
Thank You,
Tom
Theory of Gravitational Waves & LIGO
Laser Interferometer Space Antenna - LISA
JPL-Caltech
Hmm, Why are the graphs
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Hmm,
Why are the graphs 5.1 and 13.3a flat lines? Or am I missing something?