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Was LIGO’s Gravitational Wave Detection a False Alarm?

Authors:
Journal of Modern Physics, 2016, 7, 1845-1865
http://www.scirp.org/journal/jmp
ISSN Online: 2153-120X
ISSN Print: 2153-1196
DOI: 10.4236/jmp.2016.714164 October 17, 2016
Was LIGO’s Gravitational Wave
Detection a False Alarm?
Policarpo Yōshin Ulianov1, Xiaochun Mei2, Ping Yu3
1Equalix Tecnologia LTDA, Florianópolis, SC, Brazil
2Institute of Innovative Physics, Fuzhou, Fujian, China
3Cognitech Calculating Technology Institute, Los Angeles, CA, USA
Abstract
This article presents a new type of whitening filter (allowing the “passing” of some
noise sources) applied to process the data recorded in LIGO’s GW150914 and
GW151226 events. This new analysis shows that in the GW150914 event, the signals
from the collis
ion of two black holes are very similar to the 32.5 Hz noise sources
observed in both of LIGO’s detectors. It also points out that these 32.5 Hz noise
sources are powered by a 30 Hz sub harmonic, coming from the 60 Hz power system.
In the GW1226 event, the same analysis points out that the NR template is very si
m-
ilar to the 120 Hz noise source. Therefore, the signals recorded in these events were
probably generated by some small changes
with the 60 Hz frequency in the US power
grid. This can be caused, for exa
mple, by a power variation in the DC link, which can
appear in both detectors in the same 10 ms time window. As this kind of power grid
occurrence did not change the voltage levels,
it may have gone unnoticed by LIGO’s
electrical power supply’s monitoring system.
Keywords
Gravitational Waves Detection, LIGO, Laser Interferometer Gravitational
Wave Observatory
1. Introduction
The first experiment, with the objective of detecting gravitational waves, was conducted
in the 1960’s by Joseph Weber [1] at the University of Maryland. Weber used large cy-
linders of aluminum that supposedly vibrated in response to a passing gravitational
wave, an approach that did not work.
Until 2015, experimental attempts to detect gravitational waves were conducted for
How to cite this paper:
Ulianov, P.Y., Mei
,
X
.C. and Yu, P. (2016) Was LIGO’s Gravit
a-
tional Wave Detection a False Alarm?
Jou
r-
nal of Modern Physics
,
7
, 1845-1865.
http://dx.doi.org/10.4236/jmp.2016.714164
Received:
August 11, 2016
Accepted:
October 14, 2016
Published:
October 17, 2016
Copyright © 201
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P. Y. Ulianov et al.
1846
over 55 years without any results. Today, LIGO’s (Laser Interferometer Gravitational-
Wave Observatory) experiment is the largest and most expensive ever built for detect-
ing gravitational waves, comprising two interferometers, one located in Hanford,
Washington, and the other in Livingston, Louisiana.
LIGO’s initial search (from 2002 to 2010) did not detect any gravitational waves,
clear evidence that there was something wrong with the first version of LIGO’s system.
In September 2015, LIGO completed a 5-year overhaul of their system at a total cost of
$620 million, making it ten times more accurate and renaming it “Advanced LIGO”.
On September 14th, 2015, shortly after “Advanced LIGO” was put into operation, it
recorded the GW150914 event. After five months of analysis on the GW150914 event’s
recorded data, a job that involves about four hundred physicists from a dozen institu-
tions, the LIGO team reported [2] the detection of its first gravitational wave. The sig-
nals related to the detection are shown in Figure 1.
On December 26th, 2015, a second gravitational wave detection was reported by the
LIGO team [3] from the GW151226 event.
For these authors, the LIGO system operated more than a decade without obtaining
any results due to some theoretical and practical problems in the basis of this experi-
ment. Detailed information about these problems can be found in articles [4] and [5],
presented in summarized form in Section 2 of this article.
The theoretical factors pointed out in Section 2 can generate plenty of controversy,
thus, the theoretical discussion can go on and on.
However, the important fact was that the data recorded by LIGO was made available
on the internet along with the program codes used for processing it. This allowed a
more thorough assessment of the “gravitational waves” recorded by LIGO, which, as
presented in Sections 3 and 4, had a strange resemblance to some noise signals coming
from the detectors.
It is important to observe that the noise levels in both of LIGO’s detectors are a hun-
dred times bigger than the expected levels of the gravitational wave signals. Thus, the
Figure 1. Gravitational wave signals from LIGO’s GW150914 event.
P. Y. Ulianov et al.
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LIGO team needs to apply some sophisticated noise filtering technique (whitening fil-
ter) in order to achieve the signals sought.
The data from LIGO’s events was evaluated by Dr. Ulianov, using a new kind of
whitening filter that allows a band pass of specific noise sources. This new filter, named
the Ulianov Whitening Filter with Noise Band-Pass (UWF-NBP), is basically a standard
whitening filter, where the “whitening effect” is canceled out over a small range of fre-
quencies. This means the UWF-NBP’s output maintains the same signal generated by a
standard whitening filter, but with a “noise signal” (in a given frequency range) added
to it.
Section 3 presents the results obtained using the UWF-NBP to process the data rec-
orded from the GW150914 event. The graphs obtained from processing this event show
a strange similarity between the signal generated by the collision of two black holes and
the 32.5 Hz noise coming from the Hanford detector. Besides this, the 32.5 Hz noise
level falls exactly when the gravitational wave is detected.
Section 4 presents the results obtained using the UWF-NBP to process the GW15-
1226 event. For this event, the noise level of the output signals (after filtering) is far
greater than that of the supposed gravitational waves detected. Furthermore, from the
GW151226 event, the medium range frequency (100 to 200 Hz) of the gravitational
wave template is strongly correlated with the 120 Hz and 180 Hz noise sources.
Thus, the UWF-NBP highlights a strong connection between the “gravitational
waves” detected and some noise sources, leading to a basic question: As these noise
sources are always present in LIGO’s detectors, why do these noises only appear in the
GW150914 and GW151226 events?
For these authors, the 32.5 Hz, 120 Hz and 180 Hz noise sources are all connected to
the 60 Hz power source. Thus, some occurrence in the power supply system (in the US
power grid) can generate frequency changes in this 60 Hz signal, affecting these noise
sources in a non-periodic manner. This non-periodic noise can avoid LIGOs filter
process, appearing to be gravitational wave signals. This point is presented in Section 5,
providing an explanation on how two random noises can be observed at same time in
both of LIGO’s detectors, due to a problem in the DC links that connect the US power
grid.
Interestingly, the second of LIGOs detections happened before the first event was
published. So, if the LIGO team had data on two gravitational wave events, why did
they not present them simultaneously in order to strengthen the evidence of true detec-
tion?
The fact is, in the GW151226 event, the level of gravitational waves is lower than the
background noise (obtained after applying the whitening filter), making this detection
highly questionable.
However, after presenting the first event through the world’s media, the LIGO team
emerged from a “bleak” period (nearly two decades of activities without any results) to
a global celebration, even with the possibility receiving the Nobel Prize in 2016.
Hence, it seems that the LIGO team considered it important to show the second
event in mid-2016 in order to ensure its discovery, with two reported detections.
P. Y. Ulianov et al.
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However, as presented in Section 6, to deal with the GW151226 event’s data, the
LIGO team changed some procedures. This leads to a change in the GW150914’s tem-
plate (from a real signal, to a complex signal), which also changes its “event time”,
shifting 18 ms. This change was not notified by the LIGO team, but can be spotted by
careful analysis of LIGO’s tutorial programs, as detailed in Section 6.
Section 7 presents the conclusion of this article, where it is clear that beyond the
theoretical questioning of LIGOs ability to actually detect gravitational waves, there is
data pointing to the fact that both of their detections are probably a false alarm.
2. Theoretical Evidence That LIGO Cannot
Detect Gravitational Waves
In this section we present only a summary of theoretical evidence that LIGO’s system
cannot detect gravitational waves. More detailed information can be found in articles
[4] and [5].
Note that the authors of the articles believe that gravitational waves exist, and fully
agree with many theoretical works [6]-[8] that deal with this theme. The point here is
that LIGO’s system has some serious mistakes, possibly preventing this experiment
from detecting gravitational waves.
2.1 The Michelson Interferometer Cannot Be
Used to Detect Gravitational Waves
According to General Relativity, gravitational waves affect spatial distance, so it simul-
taneously affects wavelengths of light. Considering this fact, the phase differences of the
laser beams propagating inside the arms of Michelson’s interferometers, are invariable,
while gravitational waves pass through them. Therefore, it was impossible for LIGO to
detect gravitational waves by using Michelson’s interferometers.
It is important to observe that the LIGO team admits that gravitational waves can
change the wavelength of light, so in LIGO’s FAQ page [9], they present the following
question:
If a gravitational wave stretches the distance between the LIGO mirrors
,
doesn't it
also stretch the wave
-
length of the laser light
?”
The answer given by the LIGO team is:
A gravitational wave does stretch and squeeze the wavelength of the light in the
arms
.
But the interference pattern doesn
t come about because of the difference be-
tween the length of the arm and the wavelength of the light
.
Instead it
s caused by the
different arrival time of the light wave
s
crests and troughs
from one arm with the ar-
rival time of the light that traveled in the other arm
.
To get how this works
,
it is also
important to know that gravitational waves do NOT change the speed of light
.”
These authors consider the LIGO team’s answer to be very confusing, showing that
they are aware of the problem, but try to avoid it. As presented in [10] this kind of “
dif-
ferent arrival time of the light waves
” could only occur in the case of two independent
laser sources placed in each interferometer arm. As LIGO’s detectors use only one laser
source (in each interferometer), the interference pattern doesn’t occur.
P. Y. Ulianov et al.
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2.2. The Results of LIGO’s Experiments Go against the
Results of Michelson’s Experiments
Before Einstein put forward Special Relativity, Michelson took a dozen years trying to
find the absolute motion of the earth, but completely failed. The explanation of SR, for
the lack of results with Michelson’s experiment, was: when the interferometer rotates,
one of the arms contracts (according to the formula of Lorentz transformation), which
leads to the speed of light being constant. Thus, the fringe interferences were un-
changed.
The method LIGO used is similar to the one used by Michelson. When a gravitation-
al wave hits the interferometer, the length of its arms and the wavelength of the gravita-
tional waves change synchronously. Making a calculation: the speed in which the earth
moves round the sun is 30,000 m/s, so the Lorentz length contraction is 5 × 10−8 meters,
5 billion times greater than the gravitational wave strain detected by LIGO’s system.
If Michelson did not observe any change in the fringe interferences, then how can
LIGO have detected it?
LIGO’s experiment was based on a failed experiment and for the same reasons it was
also destined to fail.
2.3. The Formula of General Relativity Was Applied in a Wrong Context
The formula of General Relativity used to calculate the change of distance is only suita-
ble for particles in a vacuum. The formula is unsuitable for calculating the change in
the interferometer’s arm lengths, which are fixed on the earth’s surface through elec-
tromagnetic interaction. Hence, the basis of the calculation in LIGO’s experiment is al-
so wrong.
2.4. Electromagnetic Interaction Makes LIGO’s Experiments Impossible
Electromagnetic force is 1040 greater than gravity, so gravitational waves can not violate
the balance of electromagnetic forces, making LIGO’s interferometer vibrate. The rea-
son that LIGO’s experiments fail is the same reason why Weber’s experiments also did
not work. Gravitational waves are too weak to overcome electromagnetic forces be-
tween atoms in metal, without any antenna vibration. Therefore, all gravitational wave
experiments using interferometers on the earth’s surface, including those of LIGO,
Virgo, GEO600 and TAMA300, cannot observe gravitational waves.
2.5. LIGO’s Experiments Do Not Verify the Theory of General Relativity
Even if it is true that LIGO have detected a real signal of gravitational waves (an event
of binary black holes merging), this fact does not verify Einstein’s theory of gravity. The
energy from the black holes merging was transformed into gravitational waves and
emitted into the universe’s space.
That’s all! We cannot say any more.
Thus, the logic used for the LIGO team to confirm Einstein’s theories has some
problems: At first, based on the data recorded in the laser interferometer and Einstein’s
P. Y. Ulianov et al.
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gravitational theory (a reason), they deduced that there was an event of binary black
holes merging, happening in a distant galaxy 1.3 billion years ago (a result). After,
based on the so-called consistence between the event and the data observed (a reason),
Einstein’s gravitational theory becomes verified (a result). Obviously, LIGO’s argument
is a vicious circle and logically invalid. It is difficult to understand why so many scien-
tists, who signed their names on LIGO’s papers, did not know this logical problem.
2.6. No Singularity Black Holes Were Found
In paper [11] Dr. Xiaochun points out some mistakes in the Oppenheimer deduction
that massive celestial bodies may collapse into singular black holes with infinite densi-
ties. This work highlights that the “creation” of singularity black holes, in a star col-
lapsing process, may not be something that actually occurs in nature, at least not in a
correct application of the theory of General Relativity. Besides this, until today, not a
single black hole with singularity horizon has really been found through astronomical
searching. Therefore, LIGO’s results are the only proof of the coalescence of binary
black holes. However, with so many problems happening in LIGO’s experiments, their
results are not reliable enough to confirm the existence of singularity black holes.
2.7. Interferometer’s Arm Length Variation Is a 1000 Times
Less than Nuclear Radius
When the laser hits the mirrors in the interferometer’s arms, the movement of the mir-
rors’ surfaces caused by the gravitational wave are far less than 1018 meters, which in a
nuclear atomic scale is hard to be measured. This kind of precision enters into the
quantum-scale. Not only is it far beyond the limitation of mankind’s technology, it also
violates the uncertainty principle (
~xph∆ ⋅∆
), as defined in quantum mechanics.
2.8. The Method of Numerical Relativity Is Unreliable
Einstein’s equations of gravity are non-linear and difficult to be solved. The method of
numerical relativity is put forward to deal with these kinds of problems. However, black
holes involve singularities and the law of physics is invalid in singularities. In order to
make calculation possible, lots of simplifications had to be introduced, which caused
great errors. The boundary and initial conditions have to be reset each time when the
computer is near to crashing, so the errors become cumulative. Because Einstein’s grav-
ity field equations are non-linear, a “Butterfly effect” can occur and increase the extent
of the errors. Hence, the effectiveness of numerical relativity being applied to the colli-
sion of two black holes is highly questionable.
3. The Analysis of the GW150914 Event
In February 2016, when around two hundred physicists put their name to article [2],
which announced LIGOs first detection of a gravitational wave, it is evident that
something unusual was happening. LIGO’s recorded data, from the GW150914 event,
was analyzed for over five months by hundreds of physicists, confirming it to be a true
P. Y. Ulianov et al.
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gravitational wave detection.
But, if LIGO did indeed make the first observation of a gravitational wave, why did
they need such a long analysis involving so many people?
The LIGO team knows that the big problem in their detectors is that the total noise
level is a few hundred times higher than the expected gravitational wave level. Besides
this, the whitening filter process removes all periodical signals and turns them into
white noise. Therefore, the only signals that remain in the whitening filter output are
the non periodical signals. As the gravitational waves contain non periodical signals,
they also appear in the whitening filter output. This procedure only works optimally if
all signals to be removed (noise sources) are always periodic.
But which noise source is only periodic?
Even if we consider a “very stable” noise source (that is periodic in a larger time
window), random variations will sometimes occur, changing the level of this noise
source in the detector. This means that when a noise source in LIGO’s detector has a
major variation, for a short time it becomes a non periodic signal, which appears in the
whitening filter output.
So, in fact, one single LIGO detector cannot distinguish between a gravitational wave
and a non periodic variation in a noise source. Thus, LIGO’s gravitational wave detec-
tion can only be confirmed when the two detectors receive the same signal in a shorter
window than 10 ms. This happens in the GW150914 event, indicating that it can be a
genuine detection of gravitational waves, but without actually ensuring that it is not just
random noise registered by the two detectors.
The authors downloaded the data from the GW150914 event and used the codes (in
Python language) provided by the LIGO team to analyze the recorded signals and ob-
tain the gravitational wave curves, as presented in Figure 1.
It is important to observe that the total noise levels in both detectors are four hun-
dred times greater than the level of the gravitational waves detected in GW150914
event.
This problem becomes evident in Figure 2’s curves, which represent the power spec-
trum density of some signals from LIGO’s GW150914 event. In this figure, two big
noise sources, with 32.5 Hz and 60 Hz are indicated. The black curve represents the
power spectrum density of the Numerical Relativity signal (NR strain signal). The red
curve represents the output of a whitening filter (matched NR stain signal).
In Figure 2, we can see that the whitening filter process removes the power spectrum
near to 35.5 Hz and 60 Hz from the NR strain signal. Thus, the matched NR stain signal
becomes a poor representation of the Numerical Relativity signal.
Figure 3 presents the same signals (NR strain in green and matched NR in red) in
the time domain, where we can see that the Numerical Relativity signal has some
seconds of duration, but after the whitening filter process, the matched NR signal has
less than 0.05 seconds of duration.
Due to the large number of noise sources present in LIGO’s detectors, in order to
identify if a gravitational wave was detected, the LIGO team applied two different types
of searches:
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Figure 2. Power spectrum density of signals from LIGO’s GW150914 event.
(a) (b)
Figure 3. Numerical relativity signal (in green) and matched NR signal (in red): (a) Signals at 0.6
s time window; (b) The same signals at 0.1 s time window.
Whitening filter search: This search uses a whitening filter [12] to process the rec-
orded data. This kind of filter basically transforms periodic signals into white noise,
so only the signals that are non-periodic, pass through the filter. The main problem
with the whitening filter search is that the gravitational waves also have some peri-
odic signals that are removed by the filter.
Optimal matched filtering search: This search uses thousands of templates (wave-
forms), predicted by General Relativity [13], testing each one to see if it is present in
the recorded data in one certain time window (usually 16 or 32 seconds). The main
problem with this kind of search is not giving results as gravitational wave curves
(like those given by the whitening filter). The optimal matched filtering only indi-
cates if one tested template is present in the recorded data, given as an SNR (Signal
Noise Relation) curve, where the curve peak indicates the template waveform posi-
tion.
The Ulianov Whitening Filter with Noise Band-Pass was applied to LIGO’s data rec-
orded in the GW150914 event to analyze the noise source from 31.5 to 43.5 Hz, pre-
sented in Figure 2 as the 32.5 Hz noise source.
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Figure 4 presents the results of processing LIGO’s Hanford data, using a standard
whitening filter (in green) and the UWF-NBP (in red). In this figure, it is easy to see
that the 32.5 Hz noise appears clearly in the UWF-NBP filter’s output, showing that this
new filter works.
Figure 5 presents the 32.5 Hz noise in a larger time window. In this figure, it is easy
to observe that the 32.5 Hz noise source is modulated by sinusoid, with a frequency
near to 2.5 Hz, presented as a black curve in Figure 6.
This means that the 32.5 Hz noise is generated by some kind of oscillator, with a re-
sonance frequency close to 32.5 Hz, which is “powered” by a 30 Hz signal, resulting in a
low frequency modulation (2.5 Hz = 32.5 Hz - 30 Hz). Obviously, this 30 Hz “power
source” is a sub-harmonic signal from the 60 Hz power source grid.
Figure 7 is basically the same curve from Figure 4, but now the 32.5 Hz noise level is
presented for the time before the GW150914 event (black line) and after it (blue line). If
Figure 4. Curves obtained by processing the data recorded from Hanford (H1 strain), with the
standard whitening filter (in green) and the UWF-NBP (in red). The signals are added to an off-
set value in order to appear separately.
Figure 5. Hanford’s 32.5 Hz noise source.
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Figure 6. Hanford’s 32.5 Hz noise source (in red) modulated by a sinusoid (in black), with fre-
quency of 2.5 Hz.
Figure 7. The same curves from Figure 4, observing the 32.5 Hz noise source level.
we compare the 32.5 Hz noise level in Figure 6 (the continuous curve in black) with the
32.5 Hz level in Figure 7 (the two curves in black and blue), it is easy to see that some-
thing has affected the noise level near time zero, exactly at the point where LIGO de-
tects the end of the gravitational waves. This fact leads us to question:
How can a “gravitational wave” that hits the detector, affect the 32.5 Hz noise level?
The LIGO team calculated the Numerical Relativity (NR) signal, a gravitational
waveform generated from the GW150914 event, which is supposedly connected to the
collision of two black holes. Moreover, there is a great similarity between the NR signal
and the 32.5 Hz noise source, as presented in Figure 8. In this figure, the black signal is
the NR signal multiplied by the factor of 4 × 1021 (necessary in order to keep the same
scale, as the whitening filter multiplies the input signal by this factor) and the signal in
red is the 35.5 Hz noise, obtained from the UWF-NBP’s filter.
Comparing the NR signal and the 32.5 Hz noise signal, presented in Figure 8, leads
us to question:
P. Y. Ulianov et al.
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Figure 8. The curve of the NR signal multiplied by 4 × 1021 (in black) and the 32.5 Hz noise (in
red).
Why is the NR signal, which is generated from the collision of two black holes, so
similar to the 32.5 Hz noise that continually comes from LIGO’s detector?
Why are these two signals exactly synchronized in time?
These questions point to a connection between the NR signal and the 32.5 Hz noise
in the Hanford detector, raising strong doubts as to whether LIGO have actually de-
tected a gravitational wave in the GW150914 event.
4. The Analysis of the GW151226 Event
The data from the GW151226 event was also made available on the internet by the
LIGO team, with some programs (in Python language) that enabled the plotting of the
curves in Figure 9.
In Figure 9 we can see that the whitening filter search completely fails, because the
level of the gravitational waves’ curves (in black) is lower than the white noise level (in
red and green). Thus, in the GW151226 event, the gravitational wave curves were ob-
tained by LIGO, using only the optimal matched filtering search.
Figure 10 presents the SNR curve obtained by using the optimal matched filter,
based on the gravitational wave template (the black curves in Figure 9).
To better evaluate the optimal matched filter’s results, the same gravitational wave
template was shifted by 3 seconds, defining the “GW Sim” signal, presented in Figure
11. This signal was added to LIGOs recorded data (from both detectors) in the
GW151226 event. After, the optimal matched filter was used to generate a new SNR
curve, presented in Figure 12.
As expected, in Figure 12, we can see two peaks in the SNR curve, one from the real
event (at zero time) and another from the simulated signal (at 3 s time).
The curves in Figure 12 show that the optimal matched filter can detect the gravita-
tional wave template, with the SNR near to 10. But, what happens if the simulated sig-
nal is slightly different?
To answer this question, we need to define two new “GW Sim” signals, presented in
Figure 13 in blue. They are basically the same as the curves of the gravitational wave
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Figure 9. Gravitational wave signals detected in the GW151226 event.
Figure 10. SNR curve in the GW151226 event in the Hanford detector.
Figure 11. Simulated signal added to LIGO’s recorded data in the GW151226 event.
template, with a band-pass filter applied and multiplied by a constant factor, in order to
maintain the same power level.
The signal presented in blue in Figure 13(a) was added to LIGO’s recorded data and
processed with the optimal matched filter, generating the SNR curve, presented in Fig-
ure 14.
The signal presented in blue shown in Figure 13(b), was also added to LIGO’s re-
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Figure 12. SNR curves obtained by processing the simulated signal.
(a) (b)
Figure 13. Two new simulated signals: (a) Band-pass filter (from 10 to 80 Hz) applied and mul-
tiplied by 1.5; (b) Band-pass filter (from 10 to 200 Hz) applied and multiplied by 1.1.
Figure 14. SNR curves obtained by processing the simulated signal presented in blue, shown in
Figure 13(a).
P. Y. Ulianov et al.
1858
corded data and processed with the optimal matched filter, generating the SNR curve,
presented in Figure 15.
The SNR curve in Figure 15 indicates that if the blue signal in Figure 13(b) is
present at zero time, the SNR value in the optimal matched filter output is also near to
10. This means that while LIGO may have detected the gravitational wave template (the
red curve in Figure 13(b)), it would also have detected the “GW Sim” template pre-
sented in blue in Figure 13(b).
Figure 16 presents two new curves: The red curve is the same gravitational template
(the red curve in Figure 13(b)) that was processed by a band-pass filter (from 100 to
200 Hz). The blue curve is the result of adding the 120 Hz noise source to the 180 Hz
noise source. These noise signals are obtained by applying the UWF-NBP filter to the
data recorded in the Hanford detector in the GW151226 event.
Figure 15. SNR curves obtained by processing the simulated signal presented in blue, shown in
Figure 13(b).
Figure 16. Gravitational wave template processed by a band-pass filter (100 to 200 Hz, in red)
and 120 Hz noise added to the 180 Hz noise (in blue).
P. Y. Ulianov et al.
1859
The curves in Figure 16 provide clear evidence that the GW151226 gravitational
wave template (found by the optimal matched filter) has a medium range frequency
(100 to 200 Hz) that is connected to the 120 Hz and 180 Hz noise sources that appear in
the Hanford detector. Note that these kinds of curves are also obtained in the Living-
stone detector’s recorded data in the GW151226 event.
This means that the optimal matched filter did not detect a complete template, but in
fact, may have detected the variation of frequency in the template’s medium range.
Therefore, some event in the US power grid that slightly modifies the 60 Hz frequency
(and its 120 Hz and 180 Hz harmonics) can generate a template match (in the optimal
matched filter’s search), thus, giving a high SNR value. Evidence that the optimal
matched filter is picking up some variations in noise sources can be seen in Figure 17.
If we look at the SNR values in Figure 10 again, as presented in Figure 17, we can
note that the optimal matched filter found the same gravitational wave template at
−5.87 s time with an SNR equal to 5.
This means that if the LIGO team had found a gravitational wave with an SNR equal
to 10 in the GW151226 event at zero time, they would also have found the same gravi-
tational wave with an SNR equal to 5 at −5.87 s. However, this was impossible because
no gravitational wave had occurred at this earlier time. This is further strong evidence,
that the optimal matched filter detected something else at −5.87 s, which was probably
also caused by a change in the 60 Hz frequency in the US power grid.
Besides this, we can question: What does an SNR equal to 10 really mean (indicating
a gravitational wave detection), if in the same data we find a false gravitational wave
detection, with an SNR equal to 5?
Obviously, an SNR value obtained in a time when there is only noise should, at most,
be equal to one. Thus, an SNR value of 5 (where there is no signal) indicates some error
in the SNR calculation made by the LIGO team. As the SNR calculation gives a norma-
lized curve (multiplied by a constant), we can consider that the “true” SNR value is
multiplied by some factor that, in GW151226 event, is at least equal to 5. So, dividing
Figure 17. Same SNR curves from Figure 10 in another time window for the upper graph.
P. Y. Ulianov et al.
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the SNR curve by 5, the maximum SNR value (when there is only noise), becomes equal
to 1, which is an acceptable value. Thus, for the GW151226 event, the SNR value equal
to 10 becomes a true SNR value, equal to 2.
Applying this procedure in the GW150914 event, the SNR value equal to 24 (as indi-
cated by the LIGO team) becomes a true SNR value, equal to 4.8.
Note that as the SNR values are used to calculate the “false alarm” rates in both
events, a low SNR true value gives a lower false alarm rate.
5. The Variations of Frequency in the US Power Grid
The US power grid configuration is presented in Figure 18, which shows two large in-
terconnection grids: Eastern interconnection and Western interconnection. Four DC
links (red circles) connect the Eastern Grid with the Western Grid. These DC links are
important because they allow the transmission of power from one system to another,
optimizing the generation of electricity.
An abrupt change of energy flow in the DC links can generate frequency instabilities
in these two interconnections. For example, if the Eastern interconnection has more
energy generation than its consumption, and the Western interconnection has more
consumption than it generates, these DC links can be used to transfer power from the
Eastern grid to the Western one. In this case, if some of the DC links open (due to an
operational problem), the Eastern grid generators will become momentarily unloaded
and tend to rotate faster. At the same time, the Western grid’s generators will become
momentarily overloaded and will tend to rotate slower. In a few seconds, the genera-
tor’s controls will act (for example, by varying the angle of the hydroelectric turbine’s
blades, or changing the fuel injection in some of the thermoelectric generators), chang-
ing the total active power generated in each grid. This means that a DC link event will
generate a small 60 Hz frequency change over the whole US power grid in the same
time window.
The LIGO system monitors the fluctuations of the power grid [14], using “power
voltage monitors” that are installed in the electronics room of each building.
Thus, LIGO’s power monitoring did not detect the 60 Hz frequency variations of the
power grid, because the voltage level did not change.
Figure 18. US Power Grid. Four DC links (red circles) connect Eastern Grid and Western Grid.
P. Y. Ulianov et al.
1861
For example, a small change in the 60 Hz frequency (e.g. from 60.1 Hz to 59.9 Hz)
can cause a notable phase shift in the 32.5 Hz noise source (e.g. a 0.2 Hz variation,
causing a time shift of 0.032 s). This produces a transitory signal that may be related to
the high frequency signals of a 0.05 s duration, recorded by the LIGO team in the
GW150914 event, which is associated with a gravitational wave signal.
Furthermore, variations in the 60 Hz frequency (that generate the variations in the
120 Hz and the 180 Hz noise sources) may also have been detected as a gravitational
wave template, by LIGOs optimal matched filtering search in the GW151226 event.
6. LIGO’s “Little Trickery” in the GW150914 Event
The analysis presented in this article is based on information provided by the LIGO
team, including several papers, tutorials, data recorded from the GW150914 and
GW151226 events and the Python programs used to process the data.
LIGO provides two tutorial programs that process the data recorded from the
GW150914 event:
GW150914_tutorial.py: This python code [15] was originally developed to be ap-
plied to just the GW150914 events recorded data. The code uses the whitening fil-
ter, but without using the optimal matched filtering search.
LOSC_Event_tutorial.py: This python code [16] was presented to deal with the
GW150914 and GW151226 events’ recorded data. As the whitening filter does not
work in the GW151226 event, this new code also uses the optimal matched filtering
search.
Hence, in order to validate the GW151226 event’s data, the LIGO team generated a
new type of process that must also be valid for all past events. However, from tho-
rough analysis of the GW150914 event, some problems were found when using the
two python programs.
The event time (time where the gravitational wave was detected) used as the input
parameter for each program was changed: In the GW150914_tutorial.py program
the event time is defined in code (tevent = 1126259462.422). In the LOSC_Event_
tutorial.py program the event time is read from a data file (O1_events.json that
contains: “tevent”: 1126259462.44). Thus, the event time was changed by 18 ms, a
large value, considering that 10 ms is the maximum time window for simultaneous
detection of both detectors. It is important to observe that the LOSC_Event_tutori-
al.py program can calculate the event time. Therefore, the Hanford event time is
equal to 1126259462.4414 s and the Livingston one is equal to 1126259462.4343 s,
with the difference between them also being 7 ms.
The Numerical Relativity (NR) signal used in these programs was also changed: In
the GW150914_tutorial.py program the NR signal is defined by the NR_H1 variable,
which is a vector with real data that is read from a text file
(GW150914_4_NR_waveform.txt). In the LOSC_Event_tutorial.py program the NR
signal has complex numbers that are defined by two vectors (template_c and tem-
plate_p), read from an hdf5 file (GW150914_4_template.hdf5). Figure 8 presents these
P. Y. Ulianov et al.
1862
two kinds of NR signals, where it is easy to observe that when the time is near to zero,
the signals are synchronized. Nevertheless, for the initial times (negative time values)
the signals are shifted. Obviously, the real part (green signal) and the imaginary part
(blue signal) of the complex template should be 90 degrees out of phase. But, if the NR
signal used in both programs represents the same gravitational wave, the NR_H1(red
signal) signal peaks are expected to be somewhere in the middle of the red and green
curves, as indicated in the red text in Figure 19.
To publish the data and programs associated with the second gravitational wave de-
tection (the GW151226 event), the LIGO team had to make a new program to accom-
modate the GW151226 event’s results. But this new program also needs to be applied to
processing the GW150914 event’s data, as it would be absurd for the LIGO team to use
a new program for processing each new gravitational wave detection. Therefore, this
new program (the LOSC_Event_tutorial.py, developed to process the GW151226 event)
needs to be used to deal with all events.
Thus, the LIGO team does a little “trickery” in the GW150914 event tutorial pro-
gram, slightly changing the shape of the NR signal (from a real template to a complex
template, as presented in Figure 19) and this modifies the event’s zero time (“tevent”
input parameter), shifting its value by 18 ms. The LIGO team can explain that the com-
plex template is better and does not affect the relative time in which the gravitational
wave hits the two detectors (7 ms). However, they changed the GW150914 event’s ini-
tial time by 18 ms in the new tutorial program, without any warning.
Besides this, article [2] presents some gravitational wave curves (see Figure 20) and
indicates that: “the shaded areas show 90% credible regions for waveform reconstruc-
tions”. Though, in the GW150914 event, if we change the template from the real NR
signal (red curve in Figure 19, the same as the red curve presented in Figure 20) to the
complex template (the blue and green curves in Figure 19, that occupy a different posi-
tion in time), the gravitational wave curve will not be inside the shaded area shown in
Figure 20 (surrounding the red signal). Thus, the LIGO team claiming “the
Figure 19. NR signals associated to the GW150915 event.
P. Y. Ulianov et al.
1863
Figure 20. Figure showing NR signal presented in article [2].
shaded areas show 90% credible regions” is a con or a lie, because the new gravitational
wave template (created by the LIGO team in the LOSC_Event_tutorial.py code and also
processing the GW151226 event) comes totally out of these shaded areas.
7. Conclusions
In article [2], the first gravitational wave detection in the GW150914 event was con-
firmed by a statistical assumption:
Measured on a background equivalent to over
67,400
years of data and including a
trials factor of
3
to account for the search classes
,
its false alarm rate is lower than
1
in
22,500
years
”.
Besides this, the “false alarm rate” does not consider that an external cause can affect
both of LIGOs detectors in the same time window. Knowing that the noise sources in
both detectors are strongly connected to the 60 Hz power grid, it is evident that varia-
tions in the 60 Hz frequency can affect some noise sources.
As presented in Section 5, an event in the US power grid’s DC Links can change the
60 Hz frequencies in the Eastern interconnection and Western interconnection, affect-
ing both of LIGO’s detectors at the same time. As LIGO’s monitoring system uses
“power voltage monitors” [14], it did not detect any 60 Hz frequency variations.
It is clear and evident that LIGOs detectors have at least one source of problems (not
observed by LIGO’s monitoring system), which can affect both detectors simulta-
neously, generating a false detection of gravitational waves. This evidence alone is
enough to invalidate the “
false alarm rate lower than
1
in
22,500
years”
, denying the
statistical evidence that LIGO has detected gravitational waves in the GW150914 event.
Furthermore, the analysis of some noise sources, presented in Sections 2 and 3, using
the Ulianov Whitening Filter with Noise Band-Pass, points out some important results:
the gravitational waves’ “shapes” are very similar to some noise sources’ “shapes”, with
the signals perfectly synchronized in time; the 32.5 Hz noise source level changes ex-
actly when the gravitational waves are detected in the GW150914 event.
As a gravitational wave cannot be so similar to the noise present in the detectors and
a cosmic event cannot affect the level of a noise source in the detector, it is evident that
P. Y. Ulianov et al.
1864
both detections of the gravitational waves carried out by LIGO in 2015 are false alarms.
For these authors, it is clear that “Advanced LIGO” has improved the LIGO system,
making the detectors ten times more sensitive, but this improvement has put the detec-
tion range lower than the remaining noise level (after using the filtering techniques
available).
Hence, the first action LIGO’s managers need to do is improve its power grid moni-
toring system, observing variations in the 60 Hz frequency, which is a possible source of
false gravitational wave detections, which today is not being observed.
Secondly, the Ulianov Whitening Filter with Noise Band-Pass is a new tool that can
be used by the LIGO team to better understand the noise sources in the detectors and
can help avoid false detections.
Thirdly, a broad discussion on the theoretical bases currently used by LIGO should
be held. There are many people questioning the LIGO system, whose thoughts should
be heard in some kind of workshop open to the scientific community.
And finally, there are some alternatives for detecting gravitational waves, such as,
using the time dilation phenomenon [17]. Since time is much less subject to external
interferences, this new type of detector [10] may be able to observe low frequency gra-
vitational waves, with periods in the range of seconds, minutes or even hours.
References
[1] Weber, J. (1960)
Physical Reviews
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[2] Abbott, B.P.,
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http://dx.doi.org/10.1103/physrevlett.116.061102
[3] Abbott, B.P.,
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Physical Review Letters
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http://dx.doi.org/10.1103/physrevlett.116.241103
[4] Ulianov, P.Y. (2016)
Global Journal of Physics
, 4, 104-421.
[5] Mei, X.C. and Yu, P. (2016)
Journal of Modern Physics
, 7, 1098-1104.
http://dx.doi.org/10.4236/jmp.2016.710098
[6] Hong, L.F. (2014) Optical Resonant Cavity and Detection of Gravitational Waves. Science
Publishing Company, Singapore, 239, 246, 331.
[7] Ohanian, H.C. and Ruffini, R. (1994) Gravitation and Space-Time. WW Norton & Com-
pany Inc., New York, 155.
[8] Yun, J.W. and Xing, J.Z. (2014)
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[9] LIGO. Frequently Asked Questions. https://www.ligo.caltech.edu/page/faq
[10] Ulianov, P.Y. (2016)
Global Journal of Physics
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[11] Mei, X.C. (2014)
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[12] Abbott, B.,
et al
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Assumptions. http://arxiv.org/pdf/1602.03843.pdf
[13] Usman, S.A.,
et al
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Compact Binary Coalescence. http://arxiv.org/abs/1508.02357
[14] Abbott, B.P.,
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to Gravitational Wave Signal GW150914. arXiv: 1602.03844.
[15] LIGO. GW150914 Event Tutorial Python Code.
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[16] LIGO. GW141226 Event Tutorial Python Code.
https://losc.ligo.org/s/events/LOSC_Event_tutorial.zip
[17] Cahill, R.T. (2006)
Progress in Physics
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