Evidence of gravitational waves, or evidence of confirmation bias?

[Michael]

The big yawn Michael is how you play the victim card in every post.

Not in most of my conversations with atheists (in general) on this website, or other most other Christians. I don't ever get personally attacked over any particular topic in most conversations. The only time I get personally attacked is over some topic related to astronomy, and pretty much exclusively by you two at the moment. *Occasionally* someone else will engage in that behavior, but you two take it to the next level and you do it in almost every post, including your last post.

The facts are that your posts are littered with stupid and idiotic comments, pointing these out to you are not a personal attack.

Even your characterization of those comments is a form of personal attack. Every time you have the opportunity you engage yourself in that childish nonsense. You keep hijacking my threads, taking them off *topic* and fixating on *individuals*. I wasn't the only one who was treated like that by you two either.

Your determination in defending your “formula” which are not you prepared to admit is so comprehensively wrong at the cost of embarrassing yourself is one such example.

It's simply a *rough estimate*, ultimately of how many many four tail "signals" I'm likely to get in X number of coin flips. It's not wrong as a rough estimate, but it was never even meant to be anything other than a rough estimate. You however apparently only know how to run to the internet to look up formulas simply to get a "better" figure. Since I wasn't trying to be that specific, I didn't feel compelled to even bother to look it up because I knew I could estimate it off the top of my head close enough to make my argument.

You however turned my efforts at estimating as an excuse to *hijack the thread again*. Both of you knock it off!

 

[Michael]

Ya know......

The "null hypothesis" isn't really even specific to LIGO, or biased against LIGO, so LIGO has no one to blame but themselves for not being able to distinguish their results from the null hypothesis.

The null hypothesis makes no assumptions about the existence or non-existence of gravitational waves. It makes no assumptions about the type of equipment built or used to measure them. It makes no assumptions about the particular type of data set that's used. It makes no particular assumptions about which people are involved in the process, or anything related to anything specific in terms of which methods are used to try to measure them.

The only assumption the null hypothesis makes is that regardless of the data set/noise observed in the equipment, it's caused by something other than gravitational waves, therefore there should be no correlation between any particular time stamped data set and any specific observed celestial event.

Let's review the history of the various claims of observation of gravitational waves vs. the null hypothesis. The gravitational wave null hypothesis was born in the late 1960, early 1970's with Joseph Weber.

Throughout the 1970's, Joseph Weber was *never* able in something like 311 attempts, to differentiate his findings from the null hypothesis. His claims finally (years later) "fell out of favor" because nobody could duplicate his claims and he was never able to show that the null hypothesis was inconsistent with any of his findings.

A few years ago, BICEP2 claimed to be able to correlate it's observed data set to a highly specific celestial observation (current polarized photon patterns), but alas their claim turned to dust in mere months. Because Bicep2 claimed to differentiate its data set from the null hypothesis based on specific celestial observations, their claim could in fact be falsified and it was falsified in record time from the standpoint of astronomy. That was strike two in terms of trying to beat the null hypothesis pitcher.

LIGO in 2017 *still* cannot differentiate it's findings from the null hypothesis, and it's really up to them to do so. They claimed they would be able to do so, and deliver multimessenger astronomy (null hypothesis differentiation) after hundreds of millions of dollar worth of upgrades of course. They got their money and spent the money. Where's the beef? It's been almost two full years now and I've yet to see a single paper or finding from LIGO that is not 100 percent consistent with the null hypothesis. How is that my fault or the fault of the null hypothesis? Even Bicep2 had the courage to claim to differentiate itself from the null hypothesis, but LIGO has not even done that much in two full years! *When* will they deliver on their multimessenger astronomy promise? Ever?

In the whole history of gravitational wave research, only BICEP2 was able to claim to link their data sets to observable events in space, and that claim blew up in less than six months.

For almost five decades the null hypothesis has been 100 percent consistent with respect to gravitational waves, and only one group has ever claimed to be able to link their data set to celestial events and thereby differentiate itself from the null hypothesis.

For almost five decades, the null hypothesis has held up very well and continues to hold up well to this day. At the rate LIGO is going, the null hypothesis is likely to be 100 consistent with the data for many more decades to come.

 

[sjastro]

Not in most of my conversations with atheists (in general) on this website, or other most other Christians. I don't ever get personally attacked over any particular topic in most conversations. The only time I get personally attacked is over some topic related to astronomy, and pretty much exclusively by you two at the moment. *Occasionally* someone else will engage in that behavior, but you two take it to the next level and you do it in almost every post, including your last post.

Even your characterization of those comments is a form of personal attack. Every time you have the opportunity you engage yourself in that childish nonsense. You keep hijacking my threads, taking them off *topic* and fixating on *individuals*. I wasn't the only one who was treated like that by you two either.

Michael you of all people shouldn’t give me a lecture on personal attacks.
Unlike you I wasn’t put on notice by the moderators who were approached by the astrophysicist Brian Koberlein with the suggestion of legal action against this site because of your libellous posts against him.
I don’t go onto other sites and create threads such as “Reality Check is the Clueless King of Sleaze” whom you have referred to here as “someone else”.
Nor do I change the definition of plagiarism so I can portray SelfSim as a person lacking in ethics when in fact SelfSim quite correctly pointed out Scott did engage in plagiarizing by not quoting the Lundquist equations.
This is only scratching the surface.

The moral of the story if you decide to show honesty and respect towards individuals who don’t agree, instead of behaving in the manner you do, you would probably find the level of “personal attacks” is going to fall.

It's simply a *rough estimate*, ultimately of how many many four tail "signals" I'm likely to get in X number of coin flips. It's not wrong as a rough estimate, but it was never even meant to be anything other than a rough estimate. You however apparently only know how to run to the internet to look up formulas simply to get a "better" figure. Since I wasn't trying to be that specific, I didn't feel compelled to even bother to look it up because I knew I could estimate it off the top of my head close enough to make my argument.

It is not even a rough estimate, it is COMPLETELY AND UTTERLY WRONG.
Not only does your formula not describe what you think it does for reasons already given, it generates unrealistic values when the coin toss number exceeds 64.
Even as a “rough estimate” THE PROBABILITY CANNOT EXCEED 1.
As I pointed out you cannot add the probabilities because coin tossing is an independent event.
Go read up on independent events in probability theory and you will find why your formula doesn’t work.

You however turned my efforts at estimating as an excuse to *hijack the thread again*. Both of you knock it off!

So pointing out your errors is hijacking the thread.
Readers have the right of access to factual information not personal opinion devoid of knowledge and understanding.

 

[Michael]

Michael you of all people shouldn’t give me a lecture on personal attacks.

I'm just going to ignore your constant hijack of the thread.

It is not even a rough estimate, it is COMPLETELY AND UTTERLY WRONG.

That's completely and utterly false. I gave you a perfectly good ballpark estimate related to the *specific circumstances* that I was describing. I didn't make up some "hypothetical" 100 coin example, it was related to my specific example and it was in fact a good rough estimate for *those specific* circumstances.

Not only does your formula not describe what you think it does for reasons already given,

The *reasons* you gave were pure baloney because you're applying my so called "formula" to a strawman argument, one which I personally never made. As I said, if I knew the figure would go over 1, I would have bothered to look up the actual formula, but since it wasn't necessary, I didn't bother.

it generates unrealistic values when the coin toss number exceeds 64.

So what? I never applied my rough estimate to any other example.

Even as a “rough estimate” THE PROBABILITY CANNOT EXCEED 1.

Mine didn't! You're strawman argument is just another excuse to launch yourself into another personal attack. Yawn...

As I pointed out you cannot add the probabilities because coin tossing is an independent event.

I didn't "add" anything, I gave you a rough estimate which was applicable in the specific circumstance for which I used it.

Your argument is like claiming I don't know math because my Newtonian calculation related to some slow speed event doesn't work correctly in some other example of a light speed event. I used a formula that was appropriate for the circumstances for which I used it.

Go read up on independent events in probability theory and you will find why your formula doesn’t work.

I know for a fact that it does work, and it gives me a rough estimate of how many total "signals" I might expect to get in X number of flips. It's not a perfect number because it doesn't include the influences/circumstance that I mentioned previously, and it wouldn't work in *every possible* circumstance.

It's even "sort of" applicable in your strawman argument because it still calculates the rough number of four tail "signals" I might get in x number of flips and I can ballpark the probability from it too which I even did for you.

So pointing out your errors is hijacking the thread.

No, making up "strawman errors" which I didn't make is hijacking the thread. *If* I had tried to apply my rough estimate to a scenario that went beyond 1, you might have a real complaint. Since I didn't, you created a strawman argument which *I* did not make, and used it to bash me personally *yet again*! You're 100 percent predictable in terms of that behavior.

Readers have the right of access to factual information not personal opinion devoid of knowledge and understanding.

That's actually pretty ironic coming from a guy that can't even explain how or why LIGO's findings are in any way incompatible with a null hypothesis. We all know why you keep hijacking this thread. You can't answer even the most basic questions related to the *topic of conversation*, so you go right back to attacking the individual. People see right through your nonsense sooner later.

Your entire contribution to this thread consists of one semi useful on topic post (with an obligatory ad hom of course) and a ton of personal attack nonsense.

Do you have anything to contribute to the *topic* of this thread? If not, stop hijacking the thread!

 

[SelfSim]

... Do you have anything to contribute to the *topic* of this thread? If not, stop hijacking the thread!

I see no hijack.
In fact, sjastro has convincingly demonstrated '.. evidence of confirmation bias', (as per the thread topic/title) .. with the directly exposed 'confirmation bias' being the incorrect application of math in Michael's 'approximation' argument.

I don't believe Michael's dogged assertion of 'approximation' would gain him any points, whatsoever, in any secondary school math exam. (With the exception of 'zero' points, of course).

 

[sjastro]

I see no hijack.
In fact, sjastro has convincingly demonstrated '.. evidence of confirmation bias', (as per the thread topic/title) .. with the directly exposed 'confirmation bias' being the incorrect application of math in Michael's 'approximation' argument.

I don't believe Michael's dogged assertion of 'approximation' would gain him any points, whatsoever, in any secondary school math exam. (With the exception of 'zero' points, of course).

I like how he tries to justify his formula with this remark.

Your argument is like claiming I don't know math because my Newtonian calculation related to some slow speed event doesn't work correctly in some other example of a light speed event. I used a formula that was appropriate for the circumstances for which I used it.

What he should have stated is to take the math for the high speed equation in this case the Lorentz transformations. We'll assume he means near light speed event rather than light speed event.
If he plugged in low speeds it reduces to the familiar Galilean transformations.
In fact the Galiliean transformations are an approximation to the Lorentz transformations.

For the same reasons he should show us how his formula is an approximation for the equation involving Tetranacci number sequences.

 

[sjastro]

I'm just going to ignore your constant hijack of the thread.

You hijack your own thread every time you bleat about being a victim of personal attacks.

Let me remind you Michael.

“Unlike you I wasn’t put on notice by the moderators who were approached by the astrophysicist Brian Koberlein with the suggestion of legal action against this site because of your libellous posts against him.
I don’t go onto other sites and create threads such as “Reality Check is the Clueless King of Sleaze” whom you have referred to here as “someone else”.
Nor do I change the definition of plagiarism so I can portray SelfSim as a person lacking in ethics when in fact SelfSim quite correctly pointed out Scott did engage in plagiarizing by not quoting the Lundquist equations.
This is only scratching the surface.”

People in glass houses shouldn’t throw stones.

Go read up on independent events in probability theory and you will find why your formula doesn’t work.

I know for a fact that it does work, and it gives me a rough estimate of how many total "signals" I might expect to get in X number of flips. It's not a perfect number because it doesn't include the influences/circumstance that I mentioned previously, and it wouldn't work in *every possible* circumstance.

It's even "sort of" applicable in your strawman argument because it still calculates the rough number of four tail "signals" I might get in x number of flips and I can ballpark the probability from it too which I even did for you.

This encapsulates the entire thread.

Repeating the same nonsense over and over isn’t going to make it right.
Your refusal to read why independent events make a mockery of your formula is because you prefer to remain in a state of permanent ignorance rather than learning why your formula doesn’t work for any number of coin tosses.
The reason behind this is quite obvious, you don’t have the backbone of admitting you are comprehensively wrong.

This thread was effectively over with your “bold” statement that sigma must be associated with a cause and your confusion over statistical and environmental noise.
Despite the efforts of individuals over various forums to try to educate on the subject of statistical noise vs environmental noise vs signal, you choose to remain ignorant for the same reasons.

It seems the only outcome is for to continue with your ignorant ramblings and the rest of us to ignore you.
At least you won’t have to worry about being a victim of personal attacks.

 

[Michael]

I see no hijack.

Virtually every post you two make is off the *topic* and about the *individual*. It's all you two can discuss, because neither of you can demonstrate that LIGO's data is in any way inconsistent with the null hypothesis. Therefore, around around around you go, directing the conversation *off the topic*, and onto the victim of your choice.

In fact, sjastro has convincingly demonstrated '.. evidence of confirmation bias', (as per the thread topic/title) .. with the directly exposed 'confirmation bias' being the incorrect application of math in Michael's 'approximation' argument.

LOL! The problem was *cherry picking*, not the calculation itself! Wow. Talk about denial. Had I questioned their sigma figure, you line of attack might be logical. As it stands, it's obviously a diversion from the fact that you refuse to deal with their cherry picking problem, their inability to eliminate environmental noise in any *quantified* manner, their inability to differentiate between correlated blip transients and gravitational waves, and their inability to demonstrate that their data is in any way inconsistent with the null hypothesis. Instead of dealing with any *methodology problems*, you're both off on tangents and strawman arguments galore.

I don't believe Michael's dogged assertion of 'approximation' would gain him any points, whatsoever, in any secondary school math exam. (With the exception of 'zero' points, of course).

Your went right back to hijacking the thread, taking it *off topic* while you bash at the individual in a purely unethical manner.

For crying out loud, it was only an *approximation* to simply point out the absurdity of claiming that aliens did it! You two are are simply incapable of handling the topic.

 

[Michael]

What he should have stated......

Can't you ever discuss the *topic*? I've seen exactly *one* useful post from you in this entire thread. The rest of your posts have all been directed at the *person*.

 

[Michael]

You hijack your own thread every time you bleat about being a victim of personal attacks.

Let me remind you Michael.

I didn't ask you about a conversation that had nothing to do with you in the first place. I asked you to stop hijacking the thread.

People in glass houses shouldn’t throw stones.

If I were attacking you two personally *by your name*, using an anonymous handle no less, you might have something to whine about. As it stands, not so much.

Repeating the same nonsense over and over isn’t going to make it right.

Repetitively running from the question as to how LIGO's data is in any way inconsistent with the null hypothesis isn't going to make the problem go away.

Your refusal to read why independent events make a mockery of your formula

I didn't ever claim to hand you a "formula" which was intended or guaranteed to work in every single strawman scenario you might dream up. Even that accusation is a strawman. All I did is make a simple rough estimate to show how silly it is to claim "aliens did it" from a cherry picked data set. You simply ignored the whole cherry picking problem entirely by deflecting the conversation away from the real problem.

is because you prefer to remain in a state of permanent ignorance rather than learning why your formula doesn’t work for any number of coin tosses.

I never claimed it was intended to work "for any number of coin tosses" to begin with. That's another strawman.

The reason behind this is quite obvious, you don’t have the backbone of admitting you are comprehensively wrong.

Backbone? LIGO doesn't even have the backbone to discuss that missing veto in public. Don't talk to me about backbone. More off topic emotional nonsense.

You don't have the backbone to stick to the *topic*, or admit to your own strawmen.

This thread was effectively over with your “bold” statement that sigma must be associated with a cause and your confusion over statistical and environmental noise.

What confusion? There is no sigma figure to rule out environmental noise in the first place! That's the whole problem!

Despite the efforts of individuals over various forums to try to educate on the subject of statistical noise vs environmental noise vs signal, you choose to remain ignorant for the same reasons.

LOL! I showed you the difference in my cherry picking analogy! The only useful sigma figure would/should have applied to the *environmental* noise, not your cherry picked subset. That's the difference in a nutshell.

It seems the only outcome is for to continue with your ignorant ramblings and the rest of us to ignore you.
At least you won’t have to worry about being a victim of personal attacks.

That's fine by me. You haven't added anything of much substance to this thread to start with, and you keep running from the null hypothesis problem anyway.

 

[Michael]

1. The sigma figure provided by LIGO is meaningless with respect to cause.
2. LIGO provided no *quantified* way to eliminate ordinary environmental noise as the cause.
3. LIGO provided no quantified way to eliminate blip transients, particularly after that bombshell revelation by the Danish team and their observation of correlated noise.
4. LIGO used a highly biased methodology that favors all celestial origin claims 'by default'.
5. LIGO has provided no data whatsoever which is inconsistent with the null hypothesis.

Either discuss one of these *topics* or stop hijacking the thread.

 

[SelfSim]

1. The sigma figure provided by LIGO is meaningless with respect to cause.

The sigma figure demonstrates that a statistical noise cause is highly unlikely, (and is therefore able to be discounted as being at cause).

2. LIGO provided no *quantified* way to eliminate ordinary environmental noise as the cause.

LIGO gathered large amounts of environmental noise data from a myriad of PEM sensors which were designed specifically to test for co-incident environmental effects.

3. LIGO provided no quantified way to eliminate blip transients, particularly after that bombshell revelation by the Danish team and their observation of correlated noise.

There have been no recorded blip transients anywhere near the magnitude(s) of confirmed GWs.
Also, (as you're aware), from:
LIGO AND VIRGO COLLABORATIONS PREPARING A BRIEF GUIDE TO LIGO DETECTOR NOISE AND EXTRACTION OF GRAVITATIONAL-WAVE SIGNALS":

Recent claims in a preprint by Creswell et al. of puzzling correlations in LIGO data have broadened interest in understanding the publicly available LIGO data around the times of the detected gravitational-wave events. We see that the features presented in Creswell et al. arose from misunderstandings of public data products. The LIGO Scientific Collaboration and Virgo Collaboration (LVC) have full confidence in our published results, and we are preparing a paper in which we will provide more details about LIGO detector noise properties and the data analysis techniques used by the LVC to detect gravitational-wave signals and infer their waveforms."

4. LIGO used a highly biased methodology that favors all celestial origin claims 'by default'.

sjastro demonstrated that the root cause of your believed 'bias' is incorrect math.

Also, see post#198, which points out the substantial empirically measured, and widely documented evidential basis of the LIGO tests (also explained to you back in post#198 .. perhaps you've forgotten it?).

5. LIGO has provided no data whatsoever which is inconsistent with the null hypothesis.

Your so-called 'null hypothesis' leads nowhere. LIGO's continued investigation of GWs, on the other hand, has returned positive results demonstrating the existence of GWs!

Either discuss one of these *topics* or stop hijacking the thread.

Discussed above (and continually dismissed by yourself throughout this entire thread).

 

[Michael]

The sigma figure demonstrates that a statistical noise cause is highly unlikely, (and is therefore able to be discounted as being at cause).

If by "statistical noise" you mean *detector* noise(s), ok, we can likely rule out that *one* possible cause (detector noise) from further consideration. Since it was unlikely that local detector noise would produce correlated noise to start with, that should hardly surprise us. There are however a variety of other possible environmental causes which must also be statistically eliminated.

A five sigma elimination of one potential cause of the noise pattern does not mean that we have 'discovered' anything other than the fact that we "discovered" that we confidently eliminate that *one* possible cause. We can make no other claims about "discovery" based on the elimination of one possible cause of the signal.

All other possible potential environmental causes remain on the table. All claims as to cause would also have to include a statistical elimination calculation related to all potential environmental influences in order to make any claims about discovering a cause of the signal.

LIGO gathered large amounts of environmental noise data from a myriad of PEM sensors which were designed specifically to test for co-incident environmental effects.

And the specific signal was originally vetoed by that myriad of external sensors with "high confidence". While the veto was later deemed to be "unsafe", LIGO provided no quantified definition of "safety" in terms of how "safely" we can ignore the potential environmental factors which that veto was originally designed to detect.

Furthermore, we have no certainty that those PEM sensors are 100 percent perfect at detecting all possible environmental factors. In fact we already know that they are not 100 percent perfect because of the blip transient phenomenon which cannot be traced back to any specific environmental sensor, yet blip transients routinely affect one detector or the other. This demonstrates that blip transients are an environmentally caused phenomenon which are not detected by the array of PEM sensors.

There is no quantified definition of "safety" associated with any of those detectors or 'unsafe' vetoes. LIGO provided no quantified sigma figure associated with the "safety", or the reliability of those PEM detectors and "unsafe" vetoes.

There have been no recorded blip transients anywhere near the magnitude(s) of confirmed GWs.

They just got done completing a *major* upgrade of the sensitivity of the equipment, so why would that surprise us, particularly during the "engineering run" when the new equipment is just being 'tested'?

Also, (as you're aware), from:
LIGO AND VIRGO COLLABORATIONS PREPARING A BRIEF GUIDE TO LIGO DETECTOR NOISE AND EXTRACTION OF GRAVITATIONAL-WAVE SIGNALS":

That's a little "handwavy" and devoid of useful substance. Does that statement mean that "yes", there is correlated noise in the raw data, but their 'special filtering process' eliminated, some, most, or all of that correlated noise? Does that mean that "no, there really isn't any correlated noise at all"? If there is correlated noise present in the raw data, how *exactly* did they quantitatively ensure that they removed all correlated noise? I have no idea yet because there's nothing of substance to that press release to work with.

Right now the Danish team's conclusions remain unchallenged so I have to assume that there is correlated noise in the raw data which would be devastating to LIGO's claim to have eliminated blip transients based on the *assumption* that blip transients cannot ever be correlated.

sjastro demonstrated that the root cause of your believed 'bias' is incorrect math.

It's not a math related problem to start with, it's a *methodology problem*. All other environmental claims as to cause were required to pass some sort of external "PEM" detector test or they were eliminated from further consideration without any respect to "safety". On the other hand, all celestial origin claims were exempted from any external detector test whatsoever. If they had used *consistent* procedures, the lack of external corroboration from any satellite in space or on Earth should exempt celestial origin claims from further consideration too, and the noise pattern should end up in the "unknown origin" category. LIGO doesn't even allow for that possibility in their methodology. Their methodology automatically and instantly favors all celestial origin claims.

It's not a math problem, it's a *procedural* problem, and a classification problem which directly relates to their null hypothesis problem.

Also, see post#198, which points out the substantial empirically measured, and widely documented evidential basis of the LIGO tests (also explained to you back in post#198 .. perhaps you've forgotten it?).

Perhaps you've forgotten that all that demonstrated is the *possibility* that the specific noise pattern could be related to BH-BH mergers, but it does not quantitatively describe or speak to the *probability* that the noise pattern in question is necessarily related to such an event.

The fact it *could* be related to such an event does not allow us to claim that it *must* be related to such an event. Blip transients can also produce similar signals.

Your so-called 'null hypothesis' leads nowhere.

I'm really starting to wonder if you actually understand the purpose of a null hypothesis. It's not supposed to 'lead' us anywhere. It's only supposed to ensure that the claim which is being made is somehow inconsistent with the results which we might expect if the noise/data pattern in question is not related to gravitational waves. So far nothing which LIGO has published is inconsistent with the null hypothesis. Nothing that Joseph Weber ever published was inconsistent with the null hypothesis either. Only BICEP2 ever claimed to be able to differentiate between their data pattern and a null hypothesis, but it didn't hold up to long term scrutiny.

LIGO's continued investigation of GWs, on the other hand, has returned positive results demonstrating the existence of GWs!

Ya, it's returned positive results which are 100 percent consistent with the null hypothesis too.

Discussed above (and continually dismissed by yourself throughout this entire thread).

Thank you. I appreciate the professionalism.

 

[sjastro]

Selfsim,

This thread needs to be developed with an injection of real science instead of the opinion based zero knowledge zero understanding that has prevailed.

A good starting point is to look at the mathematics behind gravitational waves and the resultant physical interpretations that have been confirmed by LIGO.
This can be the propagation of GWs (gravitational waves) through spacetime or their creation.
The propagation aspect is the “easy part” and will be described as the mathematics behind the creation of gravitational waves, apart from being very complicated, is outside the boundaries of conventional general relativity and the scope of this forum.

I’ll rehash some of the maths that I described in the “We almost live in a Static Universe” thread on metrics and how this is applied to the propagation of gravitational waves through spacetime.

The concept of a metric.
You have heard of the saying the shortest distance between two points is a straight line.
This is only true in flat space and can be mathematically expressed using Pythagoras theorem for a right angle triangle. C²=A²+B².
In this case C is the distance, A and B being the horizontal and vertical distances respectively.
In x-y coordinates with segments dx and dy the equation is ds²=dx²+dy².
ds²=dx²+dy² is known as a metric.
In 3D flat space the metric is ds²=dx²+dy²+dz².

On the surface of a sphere, the shortest distance between two points is not a straight line but an arc.
In this case the metric is ds²=r²(dθ²+sin²θdΦ) where r is the radius of the sphere, θ, Φ are the latitudinal and longitudinal angles respectively.

These metrics are spatial metrics, however since relativity uses spacetime there is an extra time term c²dt² where c is the speed of light.
The metrics for space time are the difference between the time term and the spatial terms.
Metrics simply describe a property of spacetime.

In 3D flat spacetime the metric is ds²=c²dt²-dx²-dy²-dz².

This metric is known as the Lorentz metric and describes the properties of spacetime in the absence of matter and gravity.
This is a static metric whose properties do not change with time.

Metrics are solutions to Einstein’s field equations

Rₐₑ - (1/2)Rₐₑ + Λgₐₑ = -(8πG/c^4)Tₐₑ

This equation tells us of the relationship between gravity and spacetime.
When gravity is absent (no mass) spacetime is flat otherwise gravity curves spacetime.
Λ is the cosmological constant for an accelerating Universe.
The right hand term indicates the presence of matter.

For the Lorentz metric we can simplify the field equations.
Since the Lorentz metric describes static flat space time in the absence of matter Λ=0 and the right hand term vanishes.
The field equations are reduced to the vacuum form.

Rₐₑ = 0.

We can now mathematically model the propagation of a GW through spacetime using the Lorentz metric as a starting point.
Before the onset of the GW spacetime is static and flat and is described by the Lorentz metric

ds²=c²dt²-dx²-dy²-dz².

When the GW passes through this static flat space time we use a principle known as perturbation theory to describe how the metric changes when a GW is present.
We assume the metric undergoes a small perturbation or variation which effects the c²dt², dx²,dy² and dz² coefficients of the metric.

This perturbed Lorentz metric has the form.

ds²=(1+F00)c²dt²-(1+F11)dx²-(1+F22)dy²-(1+F33)dz².

At this stage all we know about F00, F11, F22 and F33 is that they are time dependant functions.
Collectively they are described as the general term Fab.

If we assume that the Fab terms are very small, the perturbed metric is flat enough to be a solution to the field equations Rₐₑ = 0.
We can plug the metric into the field equations and after some very tedious calculations this leads to a more general equation.

□²Fab= δ²Fab/δx²+ δ²Fab/δy²+ δ²Fab/δz²-(1/c²) δ²Fab/δt² where □ is the D’Alembert operator.

This complicated equation known as the Helmholtz equation which is well known in electrodynamics theory gives us a wealth of information and allows us to make some physical interpretations of the Fab terms.
The Fab terms are gravitational potentials of a gravitational field and travel at the speed of light c.
The Helmoltz equation being a wave equation immediately tells us that the Fab terms have wave like properties.
The gravitational forces act transversely to the direction of motion of the wave and have the unusual property of compressing objects in spacetime in one direction while stretching them in the 90 degree direction.
Whereas gravity has a spherical symmetry, gravitational waves have a quadrupole symmetry which can be visualized as an ellipsoid or football shape.

These are not assumptions but what the mathematics tells us and allows predictions on which experiments are developed.

The stretching/compression of objects in the presence of gravitational waves in theory can be detectable by the use of masses attached to springs with specific damping and elastic characteristics, the assembly tuned to a particular resonance frequency.
This formed the basis of Weber’s experiment.
Unfortunately this method failed due to lack of sensitivity and the extreme difficulty of isolating the experiment from external vibrations.
A much more sensitive method is to exploit the quadrupole symmetry of the GWs by the use of laser interferometers as used by LIGO.
Due to quadrupole symmetry of a passing GW one arm of the interferometer is displaced differently to the other arm resulting in a laser interference pattern.

LIGO’s discovery of GWs is a triumph of quantum limited laser interferometry.

 

[Michael]

Selfsim,

This thread needs to be developed with an injection of real science instead of the opinion based zero knowledge zero understanding that has prevailed.

A good starting point is to look at the mathematics behind gravitational waves and the resultant physical interpretations that have been confirmed by LIGO.
This can be the propagation of GWs (gravitational waves) through spacetime or their creation.
The propagation aspect is the “easy part” and will be described as the mathematics behind the creation of gravitational waves, apart from being very complicated, is outside the boundaries of conventional general relativity and the scope of this forum.

I’ll rehash some of the maths that I described in the “We almost live in a Static Universe” thread on metrics and how this is applied to the propagation of gravitational waves through spacetime.

The concept of a metric.
You have heard of the saying the shortest distance between two points is a straight line.
This is only true in flat space and can be mathematically expressed using Pythagoras theorem for a right angle triangle. C²=A²+B².
In this case C is the distance, A and B being the horizontal and vertical distances respectively.
In x-y coordinates with segments dx and dy the equation is ds²=dx²+dy².
ds²=dx²+dy² is known as a metric.
In 3D flat space the metric is ds²=dx²+dy²+dz².

On the surface of a sphere, the shortest distance between two points is not a straight line but an arc.
In this case the metric is ds²=r²(dθ²+sin²θdΦ) where r is the radius of the sphere, θ, Φ are the latitudinal and longitudinal angles respectively.

These metrics are spatial metrics, however since relativity uses spacetime there is an extra time term c²dt² where c is the speed of light.
The metrics for space time are the difference between the time term and the spatial terms.
Metrics simply describe a property of spacetime.

In 3D flat spacetime the metric is ds²=c²dt²-dx²-dy²-dz².

This metric is known as the Lorentz metric and describes the properties of spacetime in the absence of matter and gravity.
This is a static metric whose properties do not change with time.

Metrics are solutions to Einstein’s field equations

Rₐₑ - (1/2)Rₐₑ + Λgₐₑ = -(8πG/c^4)Tₐₑ

This equation tells us of the relationship between gravity and spacetime.
When gravity is absent (no mass) spacetime is flat otherwise gravity curves spacetime.
Λ is the cosmological constant for an accelerating Universe.
The right hand term indicates the presence of matter.

For the Lorentz metric we can simplify the field equations.
Since the Lorentz metric describes static flat space time in the absence of matter Λ=0 and the right hand term vanishes.
The field equations are reduced to the vacuum form.

Rₐₑ = 0.

We can now mathematically model the propagation of a GW through spacetime using the Lorentz metric as a starting point.
Before the onset of the GW spacetime is static and flat and is described by the Lorentz metric

ds²=c²dt²-dx²-dy²-dz².

When the GW passes through this static flat space time we use a principle known as perturbation theory to describe how the metric changes when a GW is present.
We assume the metric undergoes a small perturbation or variation which effects the c²dt², dx²,dy² and dz² coefficients of the metric.

This perturbed Lorentz metric has the form.

ds²=(1+F00)c²dt²-(1+F11)dx²-(1+F22)dy²-(1+F33)dz².

At this stage all we know about F00, F11, F22 and F33 is that they are time dependant functions.
Collectively they are described as the general term Fab.

If we assume that the Fab terms are very small, the perturbed metric is flat enough to be a solution to the field equations Rₐₑ = 0.
We can plug the metric into the field equations and after some very tedious calculations this leads to a more general equation.

□²Fab= δ²Fab/δx²+ δ²Fab/δy²+ δ²Fab/δz²-(1/c²) δ²Fab/δt² where □ is the D’Alembert operator.

This complicated equation known as the Helmholtz equation which is well known in electrodynamics theory gives us a wealth of information and allows us to make some physical interpretations of the Fab terms.
The Fab terms are gravitational potentials of a gravitational field and travel at the speed of light c.
The Helmoltz equation being a wave equation immediately tells us that the Fab terms have wave like properties.
The gravitational forces act transversely to the direction of motion of the wave and have the unusual property of compressing objects in spacetime in one direction while stretching them in the 90 degree direction.
Whereas gravity has a spherical symmetry, gravitational waves have a quadrupole symmetry which can be visualized as an ellipsoid or football shape.

These are not assumptions but what the mathematics tells us and allows predictions on which experiments are developed.

The stretching/compression of objects in the presence of gravitational waves in theory can be detectable by the use of masses attached to springs with specific damping and elastic characteristics, the assembly tuned to a particular resonance frequency.
This formed the basis of Weber’s experiment.
Unfortunately this method failed due to lack of sensitivity and the extreme difficulty of isolating the experiment from external vibrations.
A much more sensitive method is to exploit the quadrupole symmetry of the GWs by the use of laser interferometers as used by LIGO.
Due to quadrupole symmetry of a passing GW one arm of the interferometer is displaced differently to the other arm resulting in a laser interference pattern.

LIGO’s discovery of GWs is a triumph of quantum limited laser interferometry.

Cool! Two on topic posts in a row. I'm stunned (and happy).

Now that you've provided us with some useful background on GR theory and how it ties back to interferometry technology that is used in LIGO, could you please address the five specific problems in their methodology which I listed earlier?

1. The sigma figure provided by LIGO is meaningless with respect to cause.
2. LIGO provided no *quantified* way to eliminate ordinary environmental noise as the cause.
3. LIGO provided no quantified way to eliminate blip transients, particularly after that bombshell revelation by the Danish team and their observation of correlated noise.
4. LIGO used a highly biased methodology that favors all celestial origin claims 'by default'.
5. LIGO has provided no data whatsoever which is inconsistent with the null hypothesis.

 

[SelfSim]

Selfsim,

This thread needs to be developed with an injection of real science instead of the opinion based zero knowledge zero understanding that has prevailed.

Thanks for that sjastro!
Terrific post!

And, I think, after consuming (& digesting) your analysis, I'd really like to re-emphasise the main points you make, as I think these are continually overlooked by those who only see the syntax of the math (and almost nothing else).

Whilst the models you reference are described using the syntax of math, the relationships between those terms are virtually irrefutably logically justified, and it is these that result in the physical interpretations which scientists (like the LIGO consortium) tirelessly 'put to the test'.

Some of these points are repeated below (incomplete, but just for the record):

...
This equation tells us of the relationship between gravity and spacetime
...
The right hand term indicates the presence of matter.
...
We can now mathematically model the propagation of a GW through spacetime using the Lorentz metric as a starting point.
Before the onset of the GW spacetime is static and flat and is described by the Lorentz metric
...
When the GW passes through this static flat space time we use a principle known as perturbation theory to describe how the metric changes when a GW is present.
...
This complicated equation known as the Helmholtz equation which is well known in electrodynamics theory gives us a wealth of information and allows us to make some physical interpretations of the Fab terms.
The Fab terms are gravitational potentials of a gravitational field and travel at the speed of light c.
The Helmoltz equation being a wave equation immediately tells us that the Fab terms have wave like properties.
The gravitational forces act transversely to the direction of motion of the wave and have the unusual property of compressing objects in spacetime in one direction while stretching them in the 90 degree direction.
...
These are not assumptions but what the mathematics tells us and allows predictions on which experiments are developed.

I whole-heartedly concur that these are real scientific predictions which describe physically real measurable quantities .. and are absolutely not, (in any way), comparable with the arm-waving: 'I predicted', (presumably because: 'I said so').

The differences between the two, is stunningly exemplified in your post.

The other point I'd like to join with you in making is that it is this physical modelling (and its testable predictions), which justify precisely, the approach taken by LIGO (including their methodolgy). Unfortunately, I doubt that this 'sank in', as being the overall main point behind your post .. so I'll attempt to repeat your words again, to emphasise it again:

The stretching/compression of objects in the presence of gravitational waves in theory can be detectable by the use of masses attached to springs with specific damping and elastic characteristics, the assembly tuned to a particular resonance frequency.
This formed the basis of Weber’s experiment.
Unfortunately this method failed due to lack of sensitivity and the extreme difficulty of isolating the experiment from external vibrations.
A much more sensitive method is to exploit the quadrupole symmetry of the GWs by the use of laser interferometers as used by LIGO.
Due to quadrupole symmetry of a passing GW one arm of the interferometer is displaced differently to the other arm resulting in a laser interference pattern.

LIGO’s discovery of GWs is a triumph of quantum limited laser interferometry.

Thanks again for such an informative and content-rich post!

At least one of us 'got it'!
Cheers

 

[Michael]

The other point I'd like to join with you in making is that it is this physical modelling (and its testable predictions), which justify precisely, the approach taken by LIGO (including their methodolgy).

I want to begin by saying that it's nice to see this discussion start to show some professionalism. I appreciate the content and tone of both of your last few posts. I mean that.

The basic problem with your logic is that LIGO has not made any testable predictions which deviate from the null hypothesis.

Blip transients routinely produce these same basic frequency and duration patterns, typically in only one detector at a time. That's how we know they are environmental in origin. They can't be traced to any auxiliary hardware detectors. There is no 'safe' veto to rule them out, and LIGO does not know their cause. If as a result of the detector upgrades there is now volume overlap in terms of their ability to detect the same distant blip transient event, they may even produce correlated noise in both detectors at the same time.

It will be very interesting to see what LIGO has to say about that correlated noise observed by the Danish team. It literally makes or breaks their claim with respect to ruling out blip transients. If in fact there are other patterns of correlated noise going on before, during and after the so called 'signal' at exactly the same time delay as the signal, it's far more likely that the cause of the other (earlier/later) correlated noise is also the cause of the noise pattern in question (signal) than it's likely that some random celestial event *just so happened* to come in and be detected at *exactly* the same time delay as the ongoing correlated noise. That would be quite a "coincidence" indeed.

If there is correlated environmental noise potential between the LIGO detectors, then LIGO cannot realistically rule out blip transients as the cause of these supposed "signals".

That's "in addition to" the fact that LIGO has never actually produced a sigma calculation to statistically rule out normal *environmental* factors to begin with, just *detector noise*.

Here's the deal:

LIGO is actually *postdicting* a fit to a basic type of 'noise pattern/waveform pattern'. The modifiable (wiggle room) variables of their mathematical models include things like distance, mass sizes, velocities, angular velocities, merger angles, charge options, etc. They can fit a *lot* of various noise patterns, not just one specific noise pattern.

While those "testable predictions" you mentioned demonstrate that various noise patterns *could* be related to celestial events, they don't rule out any other options for such noise pattern. Their mathematical models (predictions) cover a *range* of different signal patterns, and they don't eliminate other possible causes of similar signal patterns.

It's up to LIGO to demonstrate that they can actually make predictions which deviate from the null hypothesis and make good on their promise of multimessenger astronomy. Without deviating from the null hypothesis, all LIGO is demonstrating with their supposed "testable predictions" is that such signals *could* be celestial in origin, but they could be environmental in origin. LIGO cannot definitely (with 5 sigma confidence) claim that they *are certainly* celestial in origin. LIGO didn't even impose *any* elimination method on celestial origin claims, and LIGO didn't produce a specific sigma figure to rule out ordinary environmental noise, just *detector* noise.

Where's the sigma figure related to environmental noise, and where's the visual support?

 

[sjastro]

Thanks for that sjastro!
Terrific post!

And, I think, after consuming (& digesting) your analysis, I'd really like to re-emphasise the main points you make, as I think these are continually overlooked by those who only see the syntax of the math (and almost nothing else).

Whilst the models you reference are described using the syntax of math, the relationships between those terms are virtually irrefutably logically justified, and it is these that result in the physical interpretations which scientists (like the LIGO consortium) tirelessly 'put to the test'.

Some of these points are repeated below (incomplete, but just for the record):

I whole-heartedly concur that these are real scientific predictions which describe physically real measurable quantities .. and are absolutely not, (in any way), comparable with the arm-waving: 'I predicted', (presumably because: 'I said so').

The differences between the two, is stunningly exemplified in your post.

The other point I'd like to join with you in making is that it is this physical modelling (and its testable predictions), which justify precisely, the approach taken by LIGO (including their methodolgy). Unfortunately, I doubt that this 'sank in', as being the overall main point behind your post .. so I'll attempt to repeat your words again, to emphasise it again:

Thanks again for such an informative and content-rich post!

At least one of us 'got it'!
Cheers

Thanks for your comments SelfSim.

With regards to the development of the experimental physics from the theory behind GWs, Weber was at a distinct disadvantage compared to LIGO.
Apart from sensitivity issues, Weber’s detector being resonance frequency specific meant that it could only detect GW’s over a very narrow range of frequencies.
Furthermore the resonance frequency of the detector was selected in a fairly arbitrary manner.
LIGO not only had the advantage of being more sensitive and having a broader detection range, but could also be “tuned” against the theoretical strain values predicted from Numerical Relativity, an option that Weber did not have.

 

[Michael]

Thanks for your comments SelfSim.

With regards to the development of the experimental physics from the theory behind GWs, Weber was at a distinct disadvantage compared to LIGO.
Apart from sensitivity issues, Weber’s detector being resonance frequency specific meant that it could only detect GW’s over a very narrow range of frequencies.
Furthermore the resonance frequency of the detector was selected in a fairly arbitrary manner.
LIGO not only had the advantage of being more sensitive and having a broader detection range, but could also be “tuned” against the theoretical strain values predicted from Numerical Relativity, an option that Weber did not have.

That's all true. They now have three detectors to work with, and a dedicated telescope at their disposal, and yet LIGO still hasn't been able to predict or observe anything which deviates from the null hypothesis. Doesn't that worry you in the least?

While soliciting funds from the last round of upgrades LIGO 'predicted' to observe a 5/3 ratio of mass merger events favoring NS merger scenarios which should be much more visible events, and yet LIGO hasn't cited or written about a single visually supported merger scenario. Why is that, and what does that say about the predictive value of mainstream astronomy theory, or LIGO's claims and their technology?

It's hard to simply overlook the fact that there is no quantified sigma calculation related to eliminating environmental noise as the possible cause of the signal(s). The various vetoes are not quantified for "safety" as it relates to eliminating environmental sources in any way. LIGO gave all celestial origin claims a 'free pass' from elimination based on a lack of any visual/measured corroboration, unlike every other potential cause of the signal.

LIGO's ability to "fool themselves" is no better or worse than Joseph Weber. No human being has been able to produce any verified results which are in any way inconsistent with the null hypothesis to date. If that doesn't concern LIGO by now, it certainly should. The fact that LIGO hasn't delivered on multimessenger astronomy is going to concern everyone sooner or later. LIGO needs to deliver on multimessenger astronomy, or these claims will fair no better over the long haul than Joseph Weber's claims did.

With three detectors to work with, and a dedicated telescope at their disposal, I really don't see any logical excuses for not delivering on multimessenger astronomy, except of course if the null hypothesis is correct. In that scenario the null hypothesis will continue to be 100 percent consistent with all future LIGO papers, just as it is 100 percent consistent with everything that LIGO has published to date.

 

[Michael]

LSC News

Apparently August 25th, 2017 is the last day of observation run 2 (O2), and observation run 3 (O3) isn't scheduled to start up again until the fall of 2018. LIGO has to be crossing their fingers and toes about now and hoping for a miracle over the next week and a half. They desperately need an observation to write about which actually deviates from the null hypothesis, and they've got only ten more observational days to go before they start to shut it down and they start working on the next round of upgrades. If they don't produce something soon, It's going to be a long next year for LIGO.

Inquiring minds really want to know if LIGO will deliver on multimessenger astronomy in 02, or whether they're just going to remain "hopeful" of making good on that promise in 03(+)?

If that earlier Nature article was correct, and LIGO already had another 1/2 dozen potential signals to analyze back in June. It will be interesting to see if any of those 1/2 dozen+ candidate signals involves multimessenger astronomy. If none of them deviate from the null hypothesis, I really wonder how many times LIGO can rationally try to cry black hole wolf before even the 'professionals' start to publicly complain?

In the mean time, there's also that pesky Danish paper to deal with.

I'd love to be a fly on the wall at LIGO right about now.