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Old 14th February 2016, 03:20 AM   #201
query grind
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Originally Posted by Pixel42 View Post
But everyone has access to the information obtained using it.


To anyone with the necessary intellectual capacity and the willingness to put in the time and effort required to understand the science, yes.
Oh well, that's a relief.
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Old 14th February 2016, 03:33 AM   #202
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When I was a PhD student someone asked one of my fellow students who was constructing a knock-out mouse (a mouse with a gene deactivated): "What will you do for your PhD if your mouse has no phenotype" [ie no noticeably biological difference from the wild-type mouse].

The answer is, of course, you make sure your mouse has a god-damn phenotype - you haven't spent 3 year just to produce a mouse that is identical to the unmutated version.

So has the Physics community ever massively over-invested in a big ticket project? Some multi-billion dollar project that failed to met expectations?
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Old 14th February 2016, 03:41 AM   #203
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The point of the experiment was surely to find out what effect knocking out a gene has. The fact that has no effect, if indeed it does not, is just as interesting - possibly more so - than any effect it does have.

ETA: Experiments that failed to produce the expected results have historically been the most interesting. The Michaelson-Morley experiment and the project to measure how quickly the acceleration of the universe was decreasing in the 1990s (which actually established that it was increasing) spring immediately to mind.
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Old 14th February 2016, 03:43 AM   #204
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Originally Posted by Elind View Post
Anyone here NOT running seti@home since they had a PC?
I did have it years ago, but it didn't get on with my Super|Nova software, I'm sorry to say.
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Old 14th February 2016, 03:49 AM   #205
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Originally Posted by Pixel42 View Post
The point of the experiment was surely to find out what effect knocking out a gene has. The fact that has no effect, if indeed it does not, is just as interesting - possibly more so - than any effect it does have.
No, the point of the experiment was to produce an interesting paper and get a post doc position in a lab with an excellent track record of obtaining grants.

Not trying to derail, but does the pressure ever come on the physics community to justify a multibillion investment and would there ever be an incentive to ham up a less than unequivocal result?
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Old 14th February 2016, 04:00 AM   #206
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Originally Posted by query grind View Post
No, the point of the experiment was to produce an interesting paper and get a post doc position in a lab with an excellent track record of obtaining grants.
And I'm saying that a paper which describes how knocking out a gene has no effect is an interesting paper, especially if that was not the expected result. Possibly more interesting than one that describes a result which was expected.

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Not trying to derail, but does the pressure ever come on the physics community to justify a multibillion investment and would there ever be an incentive to ham up a less than unequivocal result?
The point of such experiments to find something out. If the result is not what was expected, that's often even more exciting than if it was. See my ETA to my previous post.
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Old 14th February 2016, 04:37 AM   #207
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Originally Posted by query grind View Post
No, the point of the experiment was to produce an interesting paper and get a post doc position in a lab with an excellent track record of obtaining grants.

Not trying to derail, but does the pressure ever come on the physics community to justify a multibillion investment and would there ever be an incentive to ham up a less than unequivocal result?
As someone who has worked in that field, Pixel42 hits the nail on the head. Experiments are done to determine what a gene does. Knocking it out and NOT getting a phenotype can produce quite interesting papers.
Faking a phenotype on the other hand can produce quite short careers once your successor starts working with it and has an instant 'my predecessor was wrong paper'

As for the usual 'What use is this right now' question. That is not why fundamental science is done. If that is your interest, go to industrial science. Fundamental science is humanities non-ending quest to determine the answer to the question 'Why?'. And sometime that leads to extremely useful practical science, often a century or so later.
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Old 14th February 2016, 04:47 AM   #208
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"ripples in the fabric of space and time." Nice words, but no human being can really grasp what it means. No scientist can grasp: a big bang, spacetime, quantumphysics, singularities etc. You think you understand these things because you gave it a fancy name. It is beyond our human capacity to actually understand what's going on in this world on these levels.
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Old 14th February 2016, 04:54 AM   #209
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Originally Posted by Lukraak_Sisser View Post
As someone who has worked in that field, Pixel42 hits the nail on the head. Experiments are done to determine what a gene does. Knocking it out and NOT getting a phenotype can produce quite interesting papers.
Faking a phenotype on the other hand can produce quite short careers once your successor starts working with it and has an instant 'my predecessor was wrong paper'
Can you link to any of these interesting papers?
It is fairly hard to prove scientific fraud, mostly those who get caught are careless or use photoshop (pretty much the same thing)
The only one I know of off the top of my head is Sphingosine-1-phosphate receptor-2 knock-outs.
A Japanese group and an American group both published a knock-out of these gene about the same time. The Japanese group was shown to have used photoshop to create their results and were forced to retract - I presume the PhD student didn't have much of a career after that. The American group reported very similar results and didn't use photoshop.

I know nothing about physics - which is why I was interested in Pixel's opinion of whether they might be susceptible to inflating results. She says absolutely not and I certainly have no expertise to dispute her.

I do know something about life sciences - and anyone is who suggests it isn't packed with non-reproducible results is delusional.
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Old 14th February 2016, 05:31 AM   #210
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Originally Posted by query grind View Post
I know nothing about physics - which is why I was interested in Pixel's opinion of whether they might be susceptible to inflating results. She says absolutely not and I certainly have no expertise to dispute her.
I certainly wouldn't say "absolutely not", I'm sure there are physicists who are so wedded to their pet theory they might be tempted to exaggerate or misinterpret - even fabricate - their results. But where large scale experiments are concerned the intention is to find answers to specific questions; whatever the answer turns out to be, the experiment was successful.

So for example if the LHC had finished its search for the Higgs Boson without actually finding it, that experiment would have been successful. The answer, whilst not the expected one, would have galvanised physicists to find out what was wrong with the models that predicted the existence of the Higgs boson. Indeed when the LHC was first fired up I read some interviews with physicists who declared they would be more excited by a negative result than a positive one. Likewise if LIGO had run for decades and never detected gravitational waves that would also have been an exciting result, because it would have meant that there was something seriously wrong with the General Theory of Relativity.
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Old 14th February 2016, 06:27 AM   #211
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Originally Posted by query grind View Post
Can you link to any of these interesting papers?
It is fairly hard to prove scientific fraud, mostly those who get caught are careless or use photoshop (pretty much the same thing)
The only one I know of off the top of my head is Sphingosine-1-phosphate receptor-2 knock-outs.
A Japanese group and an American group both published a knock-out of these gene about the same time. The Japanese group was shown to have used photoshop to create their results and were forced to retract - I presume the PhD student didn't have much of a career after that. The American group reported very similar results and didn't use photoshop.

I know nothing about physics - which is why I was interested in Pixel's opinion of whether they might be susceptible to inflating results. She says absolutely not and I certainly have no expertise to dispute her.

I do know something about life sciences - and anyone is who suggests it isn't packed with non-reproducible results is delusional.
The ones of the top of my head are ones I worked on myself, and I do not like to link on a public forum in order to maintain (maybe the illusion) that I can retain some anonymity online.
I can point you in a direction though. I worked on yeast genetics, rRNA biosynthesis in particular. About half the proteins in the rRNA synthesis complexes can be knocked out without a direct phenotype. A pubmed search on the current reviews about the subject and the subsequent literature should give you all the examples you'd like.
In a similar vein, the psaE protein in the cyanobacterial photosystem can be removed without a physical phenotype as other proteins get upregulated to compensate.
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Old 14th February 2016, 07:29 AM   #212
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Originally Posted by Maartenn100 View Post
"ripples in the fabric of space and time." Nice words, but no human being can really grasp what it means. No scientist can grasp: a big bang, spacetime, quantumphysics, singularities etc. You think you understand these things because you gave it a fancy name. It is beyond our human capacity to actually understand what's going on in this world on these levels.
I'm sorry, is there a reason why we can't? As far as I'm aware, we actually have a pretty good grasp of what time is, and how space-time works.
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Old 14th February 2016, 11:45 AM   #213
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Originally Posted by ben m View Post
That's exactly right. In fact, you can see both effects in that image: first the time-of-flight alone (which is measured very accurately) constrains the source to a narrow 360º ring. On top of that, they have the difference in intensities at the two sites, which (less accurately) tells you at what angle the wave passed through each detector, and that rules out a subset of the TOF-compatible ring.
I agree - rwguinn, ben_m and Cl1mh4224rd got what I was getting at. There aren't a lot of laymen descriptions of how the arms and detectors work; remember that the detector (the point) has inputs from the two arms. A fair description:

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...Because light is a wave, the two laser beams combine to make an interference pattern of bright and dark areas, or “fringes,” at that light sensor. Analyze the fringes, and you can tell how far each light wave traveled to cover the distance between the mirror and the sensor. More importantly, you can tell if that distance is changing over time. If a gravitational wave passes by, one arm of the observatory’s “L” should be stretched while the other gets squeezed, producing a telltale change in the fringe pattern.
http://www.pbs.org/wgbh/nova/next/ph...advanced-ligo/
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Old 14th February 2016, 12:57 PM   #214
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Originally Posted by ben m View Post
That's exactly right. In fact, you can see both effects in that image: first the time-of-flight alone (which is measured very accurately) constrains the source to a narrow 360º ring. On top of that, they have the difference in intensities at the two sites, which (less accurately) tells you at what angle the wave passed through each detector, and that rules out a subset of the TOF-compatible ring.
I don't know how or if the two arms can give a direction indication, but surely "intensity" difference must be a measurement artifact. How can a gravity wave that has traveled for a billion light years or more be weakened by a few hundred miles of travel?
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Old 14th February 2016, 01:31 PM   #215
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I think ben m is referring to the intensity difference due the fact that the sensitivity of each detector varies with direction (see here for a diagram), and the two detectors (the Livingston Observatory and the Hanford Observatory) have different orientations in space, being some 3000 km apart.
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Old 14th February 2016, 01:57 PM   #216
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Originally Posted by Maartenn100 View Post
"ripples in the fabric of space and time." Nice words, but no human being can really grasp what it means. No scientist can grasp: a big bang, spacetime, quantumphysics, singularities etc. You think you understand these things because you gave it a fancy name. It is beyond our human capacity to actually understand what's going on in this world on these levels.

Don't project.
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Old 14th February 2016, 02:06 PM   #217
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Originally Posted by Lukraak_Sisser View Post
The ones of the top of my head are ones I worked on myself, and I do not like to link on a public forum in order to maintain (maybe the illusion) that I can retain some anonymity online.
I can point you in a direction though. I worked on yeast genetics, rRNA biosynthesis in particular. About half the proteins in the rRNA synthesis complexes can be knocked out without a direct phenotype. A pubmed search on the current reviews about the subject and the subsequent literature should give you all the examples you'd like.
In a similar vein, the psaE protein in the cyanobacterial photosystem can be removed without a physical phenotype as other proteins get upregulated to compensate.
Neither of which are mice and the process of knocking-out a gene is a lot simpler. There is nothing surprising about knocking-out a gene and showing no phenotype, just when the investment is high it is less rewarding to report it.

The point I am asserting is the bigger the investment in time or money, the greater the psychological pressure to come up with positive results.

So in the physics area are there areas of big investments coming up with "exciting" negative results?
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Old 14th February 2016, 02:43 PM   #218
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Originally Posted by ctamblyn View Post
I think ben m is referring to the intensity difference due the fact that the sensitivity of each detector varies with direction (see here for a diagram), and the two detectors (the Livingston Observatory and the Hanford Observatory) have different orientations in space, being some 3000 km apart.
I see. Thanks

Has there been anything on what the wavelength of such an event is? My point is that if it is far larger than the detector then any expansion/contraction of space would seem to be more or less the same in all dimensions.

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Old 14th February 2016, 02:55 PM   #219
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Originally Posted by Elind View Post
I see. Thanks

Has there been anything on what the wavelength of such an event is? My point is that if it is far larger than the detector then any expansion/contraction of space would seem to be more or less the same in all dimensions.
LIGO is senstiive to wavelengths in the range ~100 to ~1000 KM IIRC, if that is what you're asking.
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Old 14th February 2016, 03:40 PM   #220
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Originally Posted by Elind View Post
I see. Thanks

Has there been anything on what the wavelength of such an event is? My point is that if it is far larger than the detector then any expansion/contraction of space would seem to be more or less the same in all dimensions.
The wavelength is much larger than the detector size, but this doesn't mean that orientation is irrelevant. Think about an incident (polarized) long wavelength electromagnetic wave (instead of a gravitational wave), and assume your linear antenna is perpendicular to the electric field of this e-m wave, you get no signal. Now assume the antenna is parallel to the E-field: you can get a signal, even if your antenna is small compared to the wavelenth (think e.g. of a portable radio receiver receiving in the medium wave band at 360 m https://en.wikipedia.org/wiki/Medium_wave).
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Old 14th February 2016, 05:22 PM   #221
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Originally Posted by Michel H View Post
The wavelength is much larger than the detector size, but this doesn't mean that orientation is irrelevant. Think about an incident (polarized) long wavelength electromagnetic wave (instead of a gravitational wave), and assume your linear antenna is perpendicular to the electric field of this e-m wave, you get no signal. Now assume the antenna is parallel to the E-field: you can get a signal, even if your antenna is small compared to the wavelenth (think e.g. of a portable radio receiver receiving in the medium wave band at 360 m https://en.wikipedia.org/wiki/Medium_wave).
I take your word for it. My mental analogy was a pressure change under a long wave tsunami, where a pressure detector that was insignificant in size to the wave would register the same change regardless of orientation. I assume that is too simplistic.

ETA: Is it really right to equate electromagnetic energy with space distortion. The former is something that can be captured in various ways. Is the latter?

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Old 14th February 2016, 06:18 PM   #222
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Originally Posted by Elind View Post
I take your word for it. My mental analogy was a pressure change under a long wave tsunami, where a pressure detector that was insignificant in size to the wave would register the same change regardless of orientation. I assume that is too simplistic.

ETA: Is it really right to equate electromagnetic energy with space distortion. The former is something that can be captured in various ways. Is the latter?
My logic went along the lines of "If we (they) can measure displacements of fractional-proton diameters, then we (they) are not going to consider something hundreds or thousands of meters long as a point"

Even though, in terms of the vastness of the Universe, even a frigging galaxy is pretty much a point...
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Old 14th February 2016, 07:20 PM   #223
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Originally Posted by Maartenn100 View Post
"ripples in the fabric of space and time." Nice words, but no human being can really grasp what it means. No scientist can grasp: a big bang, spacetime, quantumphysics, singularities etc. You think you understand these things because you gave it a fancy name. It is beyond our human capacity to actually understand what's going on in this world on these levels.
Your personal incredulity does not negate any of these that others can comprehend.

I cannot visualise 4D objects and therefore cannot quite grasp the concept.
This does not negate 4D Euclidian space.
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Old 14th February 2016, 10:46 PM   #224
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Fermi detected a Gamma-Ray burst 0.4 seconds after the event from the same location.

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With an instantaneous view of 70% of the sky, the Fermi Gamma-ray Burst Monitor (GBM) is an excellent partner in the search for electromagnetic counterparts to gravi- tational wave (GW) events. GBM observations at the time of the Laser Interferometer Gravitational-wave Observatory (LIGO) event GW150914 reveal the presence of a weak transient source above 50 keV, 0.4 s after the GW event was detected, with a false alarm probability of 0.0022. This weak transient lasting 1 s does not appear connected with other previously known astrophysical, solar, terrestrial, or magnetospheric activity. Its localization is ill-constrained but consistent with the direction of GW150914. The duration and spectrum of the transient event suggest it is a weak short Gamma-Ray Burst arriving at a large angle to the direction in which detector response is not optimal. If the GBM transient is associated with GW150914,this electromagnetic signal from a stellar mass black hole binary merger is unexpected.
http://gammaray.nsstc.nasa.gov/gbm/p...o_preprint.pdf
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Old 15th February 2016, 12:35 AM   #225
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Originally Posted by 3point14 View Post
Rats. I was so hoping for a gravity drive or somesuch.
Perhaps it could very well lead up to such a thing, or even maybe true artificial gravity.
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Old 15th February 2016, 01:06 AM   #226
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Originally Posted by carlosy View Post
Fermi detected a Gamma-Ray burst 0.4 seconds after the event from the same location.


http://gammaray.nsstc.nasa.gov/gbm/p...o_preprint.pdf
Could someone explain this, please? Is this some sort of suggestion that gravitational waves travel at the same speed as gamma rays?
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Old 15th February 2016, 01:38 AM   #227
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Originally Posted by Cl1mh4224rd View Post
...the answer I quoted does appear to address your question. Here it is again:
Quote:
Now assume that we are 2 m (~6.5 ft) tall and floating outside the black holes at a distance equal to the Earth’s distance to the Sun. I estimate that you would feel alternately squished and stretched by about 165 nm (your height changes by more than this through the course of the day due to your vertebrae compressing while you are upright).


Did you have something else in mind when you said "relatively close"? Did you have something else in mind when you said "noticeable effects"?
Tidal affects are dependent upon the size of the region under consideration. A ~2m tall person occupies a considerably smaller region than a planet or star. Similarly you won't see much affects from the tides on earth on the body of a human, but they certainly do have an affect on the oceans.

So, the fact that at that distance the gravitational waves wouldn't have a noticeable affect on a human body doesn't say much about how they would affect an object the size of a planet or star.
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Old 15th February 2016, 01:40 AM   #228
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Originally Posted by MikeG View Post
Could someone explain this, please? Is this some sort of suggestion that gravitational waves travel at the same speed as gamma rays?
Of course, they both travel at c.
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Old 15th February 2016, 01:51 AM   #229
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Originally Posted by 3point14 View Post
Rats. I was so hoping for a gravity drive or somesuch.
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Perhaps it could very well lead up to such a thing, or even maybe true artificial gravity.
Think about the impact of lasers that phenomena was only discovered in 1960.
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Old 15th February 2016, 03:32 AM   #230
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Originally Posted by carlosy View Post
Fermi detected a Gamma-Ray burst 0.4 seconds after the event from the same location.
Which is interesting not least because it tends to refute the claims of the deniers. According to their model, anything that goes against the preferred scientific orthodoxy is carefully suppressed; yet this gamma ray burst, which doesn't fit into what's expected, is being published because it's actually a very interesting result, and may well lead to some new understanding.

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Old 15th February 2016, 05:33 AM   #231
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Of course they might not be connected.
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Old 15th February 2016, 05:04 PM   #232
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Originally Posted by Elind View Post
I take your word for it. My mental analogy was a pressure change under a long wave tsunami, where a pressure detector that was insignificant in size to the wave would register the same change regardless of orientation. I assume that is too simplistic.

ETA: Is it really right to equate electromagnetic energy with space distortion. The former is something that can be captured in various ways. Is the latter?
If you rotate the antenna of your radio or television receiver, you get variable levels of signal, and the same is qualitatively true for gravitational waves detectors (though perhaps not quite as pronounced), they are also directional: if you could rotate the two long arms of a gravitational waves detector while a remote astrophysical source is emitting, you would observe also the signal level varies.
Now, if you want to see a reliable source, I can propose you this quote from the Ligo and Virgo collaborations:

(taken from: "Properties of the binary black hole merger GW150914",
The LIGO Scientific Collaboration and The Virgo Collaboration
(compiled 12 February 2016), http://arxiv.org/pdf/1602.03840v1.pdf ).
Assume for example that the remote astrophysical object emits gravitational waves with "+" polarization. Then, from equation (1), you get:
h(detector k) = F(detector k,+)h+
F(detector k,+), which expresses the directional nature of the detector, depends upon the position of the astrophysical object in the sky, so you can in principle try to use your knowledge of the signal amplitude physicists see h(detector k) to determine the source location. This is, however, difficult because the polarization of the celestial object is a priori unknown.

Last edited by Michel H; 15th February 2016 at 05:05 PM.
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Old 15th February 2016, 05:34 PM   #233
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Originally Posted by Michel H View Post
If you rotate the antenna of your radio or television receiver, you get variable levels of signal, and the same is qualitatively true for gravitational waves detectors (though perhaps not quite as pronounced), they are also directional: if you could rotate the two long arms of a gravitational waves detector while a remote astrophysical source is emitting, you would observe also the signal level varies.
Now, if you want to see a reliable source, I can propose you this quote from the Ligo and Virgo collaborations:
I take your word for it this time too. Thanks.
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Old 15th February 2016, 07:30 PM   #234
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Originally Posted by carlosy View Post
Fermi detected a Gamma-Ray burst 0.4 seconds after the event from the same location.
0.4 seconds seems quite a significant time gap between the two events if they are related- the actual event only lasted around 200ms and there wasn't expected to be much EM released. I don't think the distance between the detectors and Fermi can account for this delay.
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Old 15th February 2016, 07:47 PM   #235
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Originally Posted by Dribble Error View Post
0.4 seconds seems quite a significant time gap between the two events if they are related- the actual event only lasted around 200ms and there wasn't expected to be much EM released. I don't think the distance between the detectors and Fermi can account for this delay.
However gamma rays can take a non direct path over a billion light years distance which can account for a time delay.
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Old 15th February 2016, 07:58 PM   #236
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Originally Posted by Dribble Error View Post
0.4 seconds seems quite a significant time gap between the two events if they are related- the actual event only lasted around 200ms and there wasn't expected to be much EM released. I don't think the distance between the detectors and Fermi can account for this delay.
Keep in mind that over sufficiently long distances, electromagnetic radiation does not actually travel at c. c is the speed of light in vacuum -- in any other transparent medium light travels more slowly. Speed of light in air is about 299,700 km/s (90 km/s slower than c); in water it is about 2/3 c, and in glass 1/3 c. Interstellar space is the best vacuum in existence, but it is still not completely empty, so light travels through it a tiny, tiny bit slower than c -- and there are things which can overtake it. IIRC, neutrinos from supernova S1987A arrived on Earth 12 seconds before the light did.

Now, the above figures are for visible light. Gamma rays are far less affected by the medium through which they travel, but then, LIGO event is more than 7,000 times farther away than S1987A. If gravitational waves travel exactly at c, it is not inconceivable that associated gamma rays got delayed by 0.4 second in the course of 1.3 billion years.
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Old 15th February 2016, 09:08 PM   #237
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Originally Posted by Mark6 View Post
Keep in mind that over sufficiently long distances, electromagnetic radiation does not actually travel at c. c is the speed of light in vacuum -- in any other transparent medium light travels more slowly. Speed of light in air is about 299,700 km/s (90 km/s slower than c); in water it is about 2/3 c, and in glass 1/3 c. Interstellar space is the best vacuum in existence, but it is still not completely empty, so light travels through it a tiny, tiny bit slower than c -- and there are things which can overtake it. IIRC, neutrinos from supernova S1987A arrived on Earth 12 seconds before the light did.

Now, the above figures are for visible light. Gamma rays are far less affected by the medium through which they travel, but then, LIGO event is more than 7,000 times farther away than S1987A. If gravitational waves travel exactly at c, it is not inconceivable that associated gamma rays got delayed by 0.4 second in the course of 1.3 billion years.
I believe the primary reason for "delay" of electromagnetic radiation is because it can take the long way due to gravity wells along the way, not some medium it passes through.
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Old 15th February 2016, 10:20 PM   #238
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Originally Posted by Elind View Post
I believe the primary reason for "delay" of electromagnetic radiation is because it can take the long way due to gravity wells along the way, not some medium it passes through.
Do gravitational waves get delayed by gravity wells?
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Old 15th February 2016, 10:47 PM   #239
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Originally Posted by Mark6 View Post
Keep in mind that over sufficiently long distances, electromagnetic radiation does not actually travel at c. c is the speed of light in vacuum -- in any other transparent medium light travels more slowly. Speed of light in air is about 299,700 km/s (90 km/s slower than c); in water it is about 2/3 c, and in glass 1/3 c. Interstellar space is the best vacuum in existence, but it is still not completely empty, so light travels through it a tiny, tiny bit slower than c -- and there are things which can overtake it. IIRC, neutrinos from supernova S1987A arrived on Earth 12 seconds before the light did.

Now, the above figures are for visible light. Gamma rays are far less affected by the medium through which they travel, but then, LIGO event is more than 7,000 times farther away than S1987A. If gravitational waves travel exactly at c, it is not inconceivable that associated gamma rays got delayed by 0.4 second in the course of 1.3 billion years.
From Wiki it seems that in supernovae the neutrinos arrive earlier as they are not impeded by the material surrounding the collapsing star, whereas EM has to pass through this opaque material and is delayed through scattering. This is the case for visible light, I'm not sure if it applies to high-energy EM.

Perhaps the source of the gravitational waves is surrounded by material and the gamma rays are being generated by this material rather than the black holes themselves, and the delay is caused by the spacial distribution of the surrounding material.
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Old 15th February 2016, 11:20 PM   #240
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Perhaps the source of the gravitational waves is surrounded by material and the gamma rays are being generated by this material rather than the black holes themselves, and the delay is caused by the spacial distribution of the surrounding material.
this makes all sorts of sense tho what "sense" can be made of forces at this scale remains to be discovered....we have a start tho.

If a gamma burst turns out to be associated with gravitational wave generation each time that adds an interesting twist plus additional information on the event.

Another one who knew it was real early on...

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27
INTERVIEW 15 February 2016
I was one of the first to know gravitational waves are real
Matthew Evans is responsible for placing fake signals into LIGO data to test the system - so he knew right away that the gravitational wave signal wasn't a test
https://www.newscientist.com/article...aves-are-real/

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