DrmDoc Posted February 10, 2016 Posted February 10, 2016 Here is a link to the article announcing this expected discovery confirming Einstein's prediction. The article provides several informative links on subject and it's current research. Data results from the LIGO (Advance Laser Interferometer Gravitational-Wave Observatory) experiment will be released Thursday. Ripples in space-time detected, wow!
StringJunky Posted February 11, 2016 Posted February 11, 2016 Nice hopefully it's confirmed. Are you reasonably confident that they exist?
ajb Posted February 11, 2016 Posted February 11, 2016 Are you reasonably confident that they exist? We should wait for the announcement before getting too excited. That said, if gravitational waves are just not realised in nature then we will have to question the mathematical structure of general relativity. Given how good general relativity has been in describing other gravitational phenomena it would be real challenge to explain why gravitational waves are absent. Exciting stuff either way.
Mordred Posted February 11, 2016 Posted February 11, 2016 (edited) Are you reasonably confident that they exist? The mathematics show they should exist. Keep in mind I don't view spacetime as some fabric. ( I find the usage of the term misleading) I agree with ajb on his points. Edited February 11, 2016 by Mordred
imatfaal Posted February 11, 2016 Posted February 11, 2016 The press release THURSDAY: Scientists to provide update on the search for gravitational waves100 years after Einstein predicted the existence of gravitational waves, the National Science Foundation gathers scientists from Caltech, MIT and the LIGO Scientific Collaboration to update the scientific community on efforts to detect them.(Washington, DC) -- Journalists are invited to join the National Science Foundation as it brings together the scientists from Caltech, MIT and the LIGO Scientific Collaboration (LSC) this Thursday at 10:30 a.m. at the National Press Club for a status report on the effort to detect gravitational waves - or ripples in the fabric of spacetime - using the Laser Interferometer Gravitational-wave Observatory (LIGO).This year marks the 100th anniversary of the first publication of Albert Einstein's prediction of the existence of gravitational waves. With interest in this topic piqued by the centennial, the group will discuss their ongoing efforts to observe gravitational waves.LIGO, a system of two identical detectors carefully constructed to detect incredibly tiny vibrations from passing gravitational waves, was conceived and built by MIT and Caltech researchers, funded by the National Science Foundation, with significant contributions from other U.S. and international partners. The twin detectors are located in Livingston, Louisiana, and Hanford, Washington. Research and analysis of data from the detectors is carried out by a global group of scientists, including the LSC, which includes the GEO600 Collaboration, and the VIRGO Collaboration. http://www.ligo.org/news/media-advisory.php 1
StringJunky Posted February 11, 2016 Posted February 11, 2016 All Hail Albert! For the first time, scientists have observed ripples in the fabric of spacetime called gravitational waves, arriving at Earth from a cataclysmic event in the distant universe. This confirms a major prediction of Albert Einstein's 1915 general theory of relativity and opens an unprecedented new window onto the cosmos. http://www.sciencedaily.com/releases/2016/02/160211103935.htm
Strange Posted February 11, 2016 Posted February 11, 2016 The paper is available here: http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.061102 For some reason the server is rather slow at the moment ...
StringJunky Posted February 11, 2016 Posted February 11, 2016 The paper is available here: http://journals.aps.org/prl/abstract/10.1103/PhysRevLett.116.061102 For some reason the server is rather slow at the moment ... Umpteen million people are probably thinking the same.
iNow Posted February 11, 2016 Posted February 11, 2016 Awesome! http://apod.nasa.gov/apod/ap160211.html Explanation: Gravitational radiation has been directly detected. The first-ever detection was made by both facilities of the Laser Interferometer Gravitational-Wave Observatory (LIGO) in Washington and Louisiana simultaneously last September. After numerous consistency checks, the resulting 5-sigma discovery was published today. The measured gravitational waves match those expected from two large black holes merging after a death spiral in a distant galaxy, with the resulting new black hole momentarily vibrating in a rapid ringdown. A phenomenon predicted by Einstein, the historic discovery confirms a cornerstone of humanity's understanding of gravity and basic physics. It is also the most direct detection of black holes ever. The featured illustration depicts the two merging black holes with the signal strength of the two detectors over 0.3 seconds superimposed across the bottom. Expected future detections by Advanced LIGO and other gravitational wave detectors may not only confirm the spectacular nature of this measurement but hold tremendous promise of giving humanity a new way to see and explore our universe. 2
Commander Posted February 11, 2016 Posted February 11, 2016 Based on the observed signals, LIGO scientists estimate that the black holes for this event were about 29 and 36 times the mass of the sun, and the event took place 1.3 billion years ago. About 3 times the mass of the sun was converted into gravitational waves in a fraction of a second -- with a peak power output about 50 times that of the whole visible universe. By looking at the time of arrival of the signals -- the detector in Livingston recorded the event 7 milliseconds before the detector in Hanford -- scientists can say that the source was located in the Southern Hemisphere. >>>>>>>>>>>>>> 1.3 billion years ago ? Interesting !
Mike Smith Cosmos Posted February 11, 2016 Posted February 11, 2016 . A few comments by BBC news tonight about the detection of Gravitational waves from two black holes colliding . Announcement Interview with Stephen Hawkins A formula is shown ? The detecting LIGO TUNNEL The actual pulses from collision and received gravitation waves Mike 2
MigL Posted February 11, 2016 Posted February 11, 2016 WOW ! That is an incredible amount of mass to be converted to gravitational energy. The universe never ceases to amaze me.
StringJunky Posted February 12, 2016 Posted February 12, 2016 (edited) Nice animation. Note how the event is correlated with the signal trace at the bottom through time. Edited February 12, 2016 by StringJunky 2
StringJunky Posted February 12, 2016 Posted February 12, 2016 (edited) Nice SIM. I find it all amazing. The signal and it's visual interpretation is so clear for amateurs like myself. There's an explanation of the animation if anyone wants a bit more detail. Click "Show more" under the video at this LInK. Does this help pave the way for a better quantum description as well? Edited February 12, 2016 by StringJunky
Mordred Posted February 12, 2016 Posted February 12, 2016 Any datasets we can develop by measurement of gravities properties helps. Being able advance our understanding of its frequency and measure has numerous applications. The application of measurement beyond the electromagnetic for one, is viable. (Now we just need the moola lol) so yes it will help our understanding at the quantum level as well. (Via fine tuning by way of measurement data)
StringJunky Posted February 12, 2016 Posted February 12, 2016 (edited) Any datasets we can develop by measurement of gravities properties helps. Being able advance our understanding of its frequency and measure has numerous applications. The application of measurement beyond the electromagnetic for one, is viable. (Now we just need the moola lol) so yes it will help our understanding at the quantum level as well. (Via fine tuning by way of measurement data) Does it help towards setting limits on the dimensions of the granularity of space for quantum purposes? Edited February 12, 2016 by StringJunky
Mordred Posted February 12, 2016 Posted February 12, 2016 Yes depending on how fine tuned we can afford to measure and events to measure. The problem being how weak gravity is at the particle level. However even at this level, we can fine tune estimates. Granted more direct measurement goes a long ways... One missed property is it may allow us to find the most appropriate spin statistic to apply to gravity. The most popular being spin 2. However any bosonic spin hasn't Been ruled out afiak . Once we lock down it's spin we can narrow out it's temperature influence using the Bose- Einstien distribution formula. Which in turn can narrow out it's CMB influence. PS. How far into the future did I look lol... Any direct measurement advances all fields studying gravity.
Mike Smith Cosmos Posted February 12, 2016 Posted February 12, 2016 (edited) Are there immediate implications as to our understanding of the Cosmos ,? Black holes ? Supernova?, Big Bang ? To be Born out from this positive detection of Gravitational waves ? Mike Oops ! May have overlapped slightly ! Edited February 12, 2016 by Mike Smith Cosmos
Mordred Posted February 12, 2016 Posted February 12, 2016 Lol no prob Mike. Similar question lol bad timing.
Mike Smith Cosmos Posted February 12, 2016 Posted February 12, 2016 Lol no prob Mike. Similar question lol bad timing. Is there any way of telling , at this stage, if we are talking about :- Two miniature black holes colliding? Two supernova remnants colliding from stars? Two centres of Galaxies , namely two galaxies colliding ? Or some left over of the Big Bang ? Or something else ? Mike
Strange Posted February 12, 2016 Posted February 12, 2016 Is there any way of telling , at this stage, if we are talking about :- Two miniature black holes colliding? Two fairly big black holes colliding. One 29 times the mass of the Sun, the other 36 times the mass of the sun. This is known from the frequency of the signal and the speed at which it changed, which tells you their masses, distances and how fast they were orbiting each other (75 times a second at the end!). Nothing else could get so close before merging. And there was a characteristic "ringdown" after they merged. New Scientist has a good overview: https://www.newscientist.com/article/2077162-revolution-in-physics-as-gravitational-waves-seen-for-first-time/ Does this help pave the way for a better quantum description as well? The paper says it puts an upper bound on the mass of the graviton - but not any more than other approaches. But at least it is consistent with those. 2
Commander Posted February 12, 2016 Posted February 12, 2016 Fluctuations in the Intensity of a Force being measured at a distance will appear as a WAVE ! Which is nothing but a variation in the Field Intensity. The causing Mass which happens to be a pair of rotating Black holes creates this fluctuations. Whether it is Instantaneous or Acting at a Distance or Continuous or whether a Wave travels etc does not matter and still the same end result will be observed. This is my humble submission WHICH NEED NOT BE TRUE and I say this without any wherewithal TO READ AND ABSORB each and every EXISTING PAPERS on the Subject and therefore would not like to be CRITICISED or HECKLED for this post. Obviously I will welcome reactions from friends who would like to GUIDE ME in my line of thinking !
Strange Posted February 12, 2016 Posted February 12, 2016 Whether it is Instantaneous or Acting at a Distance or Continuous or whether a Wave travels etc does not matter and still the same end result will be observed. The reason that this is significant is that it confirms an important prediction of general relativity. This says a lot more than simply "it will be a wave". The exact shape and frequency of the wave can be calculated and compared with what is observed. The challenge is that the wave is very, very weak by the time it arrives here so it requires some amazing technology to detect it. So this detection not only confirms the mathematics of general relativity and the existence of black-hole mergers. But it also opens up a new type of astronomy, observing things that are not otherwise visible and telling us more things about the universe. I say this without any wherewithal TO READ AND ABSORB each and every EXISTING PAPERS on the Subject and therefore would not like to be CRITICISED or HECKLED for this post. I would suggest starting with the New Scientist article. It is easy to read but still accurate. 2
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