On Friday, 28 January 2022 at 14:21:08 UTC, dlzc wrote:
Dear Lou:
On Friday, January 28, 2022 at 6:38:24 AM UTC-7, Lou wrote:
Interesting to read the latest from LIGO. https://iopscience.iop.org/article/10.3847/2041-8213/ab960f
A chirp detected at Livingstone. A possible random low level chirp in the noise at Hanford and just noise at Virgo. No wonder they can’t detect “gravitational waves” at 3 detectors. It’s enough of a coincidence to get
2 possible random chirps above the noise at just two detectors
(GW150914) to claim a GW has been “observed”
To get random candidate chirps above the noise at 3 detectors
and claim it’s a GW is proving to be an impossible coincidence. Hence the latest attempts to claim noise at 2 detectors coincident with a chirp at
a third detector ,...is a GW detection!
My only issue is assuming that spatially-separated detectors with different 3D spatial orientations (largely parallel to the surface of the Earth), must necessarily return the same strength signal. Imagine an event that originates on / near the mid-
plane between a given detector's arms, will affect both arms exactly the same, would not even be detectable.
Yes. I remember this argument from when Virgo came online. They
said Virgo happened by chance to be in a one in a thousand or so
chance to be exactly positioned so it couldn’t see what the other two did.
But EVERY time? I’m sorry, but once is a just about an acceptable
excuse.
Multiple times? Every time?...is a serial offender.
They have reported GW events even when they had only two detectors online. They are still correlating with an observed "light flash" to nail down location, thereby tacitly assuming the GWs move at c.
If you mean by “light flash” as in Fermi Gammarays. I’ve studied
that connection. And it was noise. A good try though by LIGO.
We just need more detectors online. Until then it is just "pud stroking". Good practice at what we'll have to do when we have them.
David A. Smith
Hi Dave. Possibly, but I must dispute the interpretations
supplied by LIGO. Look at the data. I’ve gone over a sample
including: 170817,170814,170104,151226,190521. And there is no
definite 3 way detection yet. And Virgo came online a few years ago
now.
Arguably even only one real chirp in some of those above examples
when they’ve tried to claim 2 out of three.
(Notice that even in some GW’s I’ve cited above where it looks like
a chirp, time scale and amplitude have been fiddled with to try to
make what would be pure noise in a larger 500 scaled vertical
axis look like a vague chirp if one zooms double size to 200.
As seen for instance in GW190521. I call that fiddling the data)
Yes, You can argue one needs time or more detectors and maybe
this will happen...but not yet. And the facts *so far* show
incontrovertibly that the theorists can at best only match two
random chirps of any significance in only a handful of cases
over seven years out of 3 detectors since 2015. But never 3 .
Why this low success rate? Its called probabilities.
Because It’s just about possible in the microsecond time frame
needed to match two random chirps of significant enough magnitude
from two detectors over a year and pretend it was a GW.
But the odds of matching 3 random chirps over the year goes
up *exponentially*.
That’s why so far 3 definite chirps from three detectors have never materialised.
--- SoupGate-Win32 v1.05
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