Comments on: LIGO- Gravity wave detection rumor… https://www.habitablezone.com/2016/02/08/ligo-gravity-wave-detection-rumor/ Fri, 03 Apr 2026 22:41:18 -0700 hourly 1 http://wordpress.org/?v=3.3.1 By: bowser https://www.habitablezone.com/2016/02/08/ligo-gravity-wave-detection-rumor/#comment-35556 bowser Wed, 10 Feb 2016 02:01:38 +0000 https://www.habitablezone.com/?p=55610#comment-35556 Fascinating, RL, thanks a lot!!! Fascinating, RL, thanks a lot!!!

]]> By: RL https://www.habitablezone.com/2016/02/08/ligo-gravity-wave-detection-rumor/#comment-35555 RL Wed, 10 Feb 2016 01:29:48 +0000 https://www.habitablezone.com/?p=55610#comment-35555 The measured mass due to the cosmological redshift of the gravity wave is given by the RestMass*(1+z) where z is the redshift factor- this would also explain why the masses reported in the rumor seem too big for stellar black holes... or maybe not... according to http://stuver.blogspot.com/2011/08/q-what-waswill-be-detection-range-of.html the detection range of advanced LIGO is of order a billion ly- at a billion LY the redshift factor z would only be ~0.1... I am not an astrophysicist, I just play one on HZ... The measured mass due to the cosmological redshift of the gravity wave is given by the RestMass*(1+z) where z is the redshift factor- this would also explain why the masses reported in the rumor seem too big for stellar black holes…

or maybe not… according to http://stuver.blogspot.com/2011/08/q-what-waswill-be-detection-range-of.html the detection range of advanced LIGO is of order a billion ly- at a billion LY the redshift factor z would only be ~0.1…

I am not an astrophysicist, I just play one on HZ…

]]> By: RL https://www.habitablezone.com/2016/02/08/ligo-gravity-wave-detection-rumor/#comment-35545 RL Tue, 09 Feb 2016 02:35:16 +0000 https://www.habitablezone.com/?p=55610#comment-35545 Long hours in the lab, waiting for signals that never come.... gives you plenty of time to dream up elaborate pranks on that one loudmouthed professor that gave you a 'C-' in General Relativity 101 all those years ago... Long hours in the lab, waiting for signals that never come…. gives you plenty of time to dream up elaborate pranks on that one loudmouthed professor that gave you a ‘C-’ in General Relativity 101 all those years ago…

]]> By: RL https://www.habitablezone.com/2016/02/08/ligo-gravity-wave-detection-rumor/#comment-35544 RL Tue, 09 Feb 2016 02:13:39 +0000 https://www.habitablezone.com/?p=55610#comment-35544 http://stuver.blogspot.com/2011/03/big-dog-in-envelope.html They occasionally inject fake signals into the detectors to test the detection process: <blockquote>A blind injection is a test the higher-ups in LIGO can do to make sure that the data analysis methods are doing what they need to be doing. Basically, a very small subset of people in the collaboration (think like 2 or 3 people) inject a fake signal into the detector and this injection is not recorded anywhere like the other injections we regularly do to test things like detector calibration, etc. The fact that a blind injection exists is sealed away (in what we metaphorically call an envelope) until all due diligence is done and the collaboration is ready to declare that the signal is a detection unless it is a blind injection (that it, we prove that it is nothing in the environment or and nothing was wrong with the detectors detectors that caused the signal). </blockquote> http://stuver.blogspot.com/2011/03/big-dog-in-envelope.html

They occasionally inject fake signals into the detectors to test the detection process:

A blind injection is a test the higher-ups in LIGO can do to make sure that the data analysis methods are doing what they need to be doing. Basically, a very small subset of people in the collaboration (think like 2 or 3 people) inject a fake signal into the detector and this injection is not recorded anywhere like the other injections we regularly do to test things like detector calibration, etc. The fact that a blind injection exists is sealed away (in what we metaphorically call an envelope) until all due diligence is done and the collaboration is ready to declare that the signal is a detection unless it is a blind injection (that it, we prove that it is nothing in the environment or and nothing was wrong with the detectors detectors that caused the signal).

]]> By: RL https://www.habitablezone.com/2016/02/08/ligo-gravity-wave-detection-rumor/#comment-35543 RL Tue, 09 Feb 2016 02:00:48 +0000 https://www.habitablezone.com/?p=55610#comment-35543 Just the claim they determined masses is really odd, The observatories cant tell how far away this merger is, maybe just a general direction. Gravitational waves, like light waves, should be 'redshifted'... mass determination would be calculated from the periodicity of the orbits, but that period will also be redshifted... the observed period would be a functon of the mass of the objects plus the redshift. Without knowing the distance you shouldn't be able to estimate the mass... Just the claim they determined masses is really odd, The observatories cant tell how far away this merger is, maybe just a general direction.

Gravitational waves, like light waves, should be ‘redshifted’… mass determination would be calculated from the periodicity of the orbits, but that period will also be redshifted… the observed period would be a functon of the mass of the objects plus the redshift. Without knowing the distance you shouldn’t be able to estimate the mass…

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