Dave, I think that link was posted by H Ucar. Harry
On Fri, Feb 12, 2016 at 11:21 AM, David Roberson <[email protected]> wrote: > That paper is damaged according to my computer but I found the one that > Harry posted. > > Do you have information concerning the filtering that the signal plus > noise is subjected to before it is interpreted? Also, do these events > only take place at at low rate throughout the universe? I suppose that is > true for super nova explosions and this is likely to be just as rare of an > event. > > These teams need to be congratulated if the detections continue to be > confirmed. I remain weary of announcements that are produced so quickly. > > Dave > > > -----Original Message----- > From: Giovanni Santostasi <[email protected]> > To: vortex-l <[email protected]> > Sent: Fri, Feb 12, 2016 11:08 am > Subject: Re: [Vo]:LIGO Gravity Waves... So what? > > Here is the paper: > https://journals.aps.org/prl/pdf/10.1103/PhysRevLett.116.061102 > > The detection statistics is 5.1 sigma, that corresponds to a p value of > 3x10-7 or 1 in 3.5 million that the signal is due to chance. In the paper > they discuss the background noise and what to expect from it. > But what is more astounding is the waveform itself as detected by both > detectors (with a small time shift expected by the fact the waves travel at > the velocity of light). > You have a beautiful time evolution of the signal. In fact you can > separate the detected signal in 3 parts: inspiraling, merger and ring down. > They use relativistic approximate equations (basically an expansion with > correction at many decimal places) to find a model that fits the observed > data and only a merger of black holes with certain masses, orientation > towards the detector, spin and distance fits with high accuracy the data. > It is almost incredible how well the model actually fits the data. Besides > some non Gaussian noise that is always present in the detector the observed > waveforms look like the solution of a GR graduate textbook end of chapter > exercise problem. > > > > On Fri, Feb 12, 2016 at 10:57 AM, David Roberson <[email protected]> > wrote: > >> How can we be confident that this is not just a false alarm? It seems a >> bit premature to make this announcement since the claimed event is a >> billion light years away from Earth. Are we to assume that this particular >> event at that great distance is the only one that is showing up on the >> instrument? What proof is there that millions more are not present at >> closer distances which would be noise to filter out? >> >> Has anyone released information concerning the signal to noise for this >> discovery? Also, it is a bit difficult to believe that the device can tell >> the actual distance and direction of the black hole collision. >> >> Has this been replicated? There is much more evidence for cold fusion >> than for this discovery and I have a strong suspicion that it will be >> overturned one day. Big science making big claims again...I hope it is >> true but it is unlikely. >> >> Dave >> >> >> -----Original Message----- >> From: Giovanni Santostasi <[email protected]> >> To: vortex-l <[email protected]> >> Sent: Thu, Feb 11, 2016 9:28 pm >> Subject: Re: [Vo]:LIGO Gravity Waves... So what? >> >> By the way, gravitational waves were the topic of my dissertation so feel >> free to ask any question about the topic. It is very fascinating. >> >> On Thu, Feb 11, 2016 at 9:26 PM, Giovanni Santostasi < >> [email protected]> wrote: >> >>> It opens a complete different window on the Universe. >>> The analogy that is often given is imagine the cosmic show is like a TV >>> show. Until now we had video but not audio. Finally we turned the audio on. >>> Gravitational waves are a different but complementary way to observe the >>> universe. >>> We already learning things we could not learn before just using EM >>> radiation. For example that there are black holes systems with such large >>> masses. >>> This has consequences in terms of galaxy evolution and how stars were >>> formed. >>> And this is just the beginning. >>> The ultimate price is when we will see the gravitational waves from Big >>> Bang. >>> While the Microwave Cosmic Background tell us abut the universe at a >>> very early stage (500 K years) we cannot receive any earlier information >>> about the universe using EM radiation. >>> The equivalent gravitational wave background when detected will tells >>> information from a fraction of a second after the Big Bang. Only >>> gravitational radiation can give us a picture of the universe that early. >>> >>> Also information from events like the one just observed eventually would >>> give us clues on how gravity and quantum mechanics work together. >>> The consequences of this discovery are enormous. >>> >>> >>> >>> >>> >>> On Thu, Feb 11, 2016 at 8:22 PM, Russ George <[email protected]> >>> wrote: >>> >>>> It seems the announcement of showing gravity waves are real is only of >>>> value to obscure academic discussions. Unless someone here might illuminate >>>> us about some practical derivatives that might be revealed due to the >>>> findings. >>>> >>> >>> >> >
