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Vector theory of Gravity


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22 minutes ago, Mordred said:

I don't find it extraordinary at all there is literally 100's of alternative theories competing against GR. Is it LIGO's job to counter them or is it the physics community in general ?

The staff at LIGO's duty is to collect the data....

This situation is different for one reason in particular. Svidzinsky and Hilborn have questioned the very basis of how to properly analyze GW detections:
https://arxiv.org/abs/1812.02604
Such a serious challenge surely demands a spirited response. Not silence.

19 minutes ago, beecee said:

 

Well put Mordred, and as supported by the papers.....

Speaking for the authors of a couple of papers supporting VG4 gravity, I suppose just as any Mother believes her child to be the most beautiful, would be a good explanation. I repeat though, contrary to some pushing the VG4, and their baseless claims re incalcitrance in mainstream circles, that has been absolutely shown to be total whining and baseless excuses.

 

You refer often to a 'GV4'. Maybe confusion with Carver Mead's G4v: https://arxiv.org/abs/1503.04866
Which shares features with and may be styled a rudimentary contemporary of Svidzinsky's Vector Theory of Gravity. But a web search reveals no such animal as 'GV4' gravity.

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8 minutes ago, Q-reeus said:

This situation is different for one reason in particular. Svidzinsky and Hilborn have questioned the very basis of how to properly analyze GW detections:
https://arxiv.org/abs/1812.02604
Such a serious challenge surely demands a spirited response. Not silence.

You refer often to a 'GV4'. Maybe confusion with Carver Mead's G4v: https://arxiv.org/abs/1503.04866
Which shares features with and may be styled a rudimentary contemporary of Svidzinsky's Vector Theory of Gravity. But a web search reveals no such animal as 'GV4' gravity.

U'm actually referring to both as simply alternatives that have not surpassed GR and serious doubt s that they ever will.

There obviously has been plenty of spirited responses, as well as the usual mainstream research into all forms of the alternatives. That's how science works.

 

In the meantime....

https://www.quantamagazine.org/troubled-times-for-alternatives-to-einsteins-theory-of-gravity-20180430/

Troubled Times for Alternatives to Einstein’s Theory of Gravity

New observations of extreme astrophysical systems have “brutally and pitilessly murdered” attempts to replace Einstein’s general theory of relativity.

extract:

There are also stand-alone theories, like that of physicist Erik Verlinde. According to his theory, the laws of gravity arise naturally from the laws of thermodynamics just like “the way waves emerge from the molecules of water in the ocean,” Zumalacárregui said. Verlinde wrote in an email that his ideas are not an “alternative theory” of gravity, but “the next theory of gravity that contains and transcends Einstein’s general relativity.” But he is still developing his ideas. “My impression is that the theory is still not sufficiently worked out to permit the kind of precision tests we carry out,” Archibald said. It’s built on “fancy words,” Zumalacárregui said, “but no mathematical framework to compute predictions and do solid tests.”

The predictions made by other theories differ in some way from those of general relativity. Yet these differences can be subtle, which makes them incredibly difficult to find.

Consider the neutron-star merger. At the same time that the Laser Interferometer Gravitational-Wave Observatory (LIGO) spotted the gravitational waves emanating from the event, the space-based Fermi satellite spotted a gamma ray burst from the same location. The two signals had traveled across the universe for 130 million years before arriving at Earth just 1.7 seconds apart.

These nearly simultaneous observations “brutally and pitilessly murdered” TeVeS theories, said Paulo Freire, an astrophysicist at the Max Planck Institute for Radio Astronomy in Bonn, Germany. “Gravity and gravitational waves propagate at the speed of light, with extremely high precision — which is not at all what was predicted by those [alternative] theories.”

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1 hour ago, beecee said:

U'm actually referring to both...

Without till now ever stating that. So now revealed as a personal made up term of a quasi-generic nature.

1 hour ago, beecee said:

...as simply alternatives that have not surpassed GR and serious doubt s that they ever will.

Learn to distinguish between an assertion - as made above - and a proven established statement.

1 hour ago, beecee said:

There obviously has been plenty of spirited responses, ...

NONE in respect of what I wrote last post. But feel free to dredge up an exception (in the technical literature) I'm not aware of.

1 hour ago, beecee said:

In the meantime....

https://www.quantamagazine.org/troubled-times-for-alternatives-to-einsteins-theory-of-gravity-20180430/

Troubled Times for Alternatives to Einstein’s Theory of Gravity

New observations of extreme astrophysical systems have “brutally and pitilessly murdered” attempts to replace Einstein’s general theory of relativity.

extract:

There are also stand-alone theories, like that of physicist Erik Verlinde. According to his theory, the laws of gravity arise naturally from the laws of thermodynamics just like “the way waves emerge from the molecules of water in the ocean,” Zumalacárregui said. Verlinde wrote in an email that his ideas are not an “alternative theory” of gravity, but “the next theory of gravity that contains and transcends Einstein’s general relativity.” But he is still developing his ideas. “My impression is that the theory is still not sufficiently worked out to permit the kind of precision tests we carry out,” Archibald said. It’s built on “fancy words,” Zumalacárregui said, “but no mathematical framework to compute predictions and do solid tests.”

The predictions made by other theories differ in some way from those of general relativity. Yet these differences can be subtle, which makes them incredibly difficult to find.

Consider the neutron-star merger. At the same time that the Laser Interferometer Gravitational-Wave Observatory (LIGO) spotted the gravitational waves emanating from the event, the space-based Fermi satellite spotted a gamma ray burst from the same location. The two signals had traveled across the universe for 130 million years before arriving at Earth just 1.7 seconds apart.

These nearly simultaneous observations “brutally and pitilessly murdered” TeVeS theories, said Paulo Freire, an astrophysicist at the Max Planck Institute for Radio Astronomy in Bonn, Germany. “Gravity and gravitational waves propagate at the speed of light, with extremely high precision — which is not at all what was predicted by those [alternative] theories.”

Need I point out nothing in that article has 'brutally and pitilessly murdered' Svidzinsky's Vector Theory of Gravity? Evidently so.

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30 minutes ago, Q-reeus said:

Without till now ever stating that. So now revealed as a personal made up term of a quasi-generic nature.

Not sure why I need to state it. You certainly know my position as far as the incumbent model goes, just as I know your position with your alternative/s hypotheticals.

Quote

Learn to distinguish between an assertion - as made above - and a proven established statement.

I know for a fact that V4G and/or any other model are still also rans, though to the credit of aLIGO, VIRGO, research is still being done to  test all, according to current known pricisions with available equipement. Although the greater precision of LISA may be needed to further validate GR or one of the other.

Quote

NONE in respect of what I wrote last post. But feel free to dredge up an exception (in the technical literature) I'm not aware of.

Plenty of doubt and refutation if you read all the links I have given, and of course as Mordred has mentioned, why aLIGO needs to signal out your pet hypothetical is a mystery.

Quote

Need I point out nothing in that article has 'brutally and pitilessly murdered' Svidzinsky's Vector Theory of Gravity? Evidently so.

Need I point out that Svidzinky's has been murdered in some quarters in the opinions of some reputable experts, as per the article,  while others are still considering it and continuing research and testing as is the case in all instances of GR and any potential superior model, I'm sure you will agree.. 

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18 minutes ago, beecee said:

...just as I know your position with your alternative/s hypotheticals.

Actually I don't think you do. Or certainly don't care to present it accurately if you do know it.

18 minutes ago, beecee said:

I know for a fact that V4G and/or any other model are still also rans, though to the credit of aLIGO, VIRGO, research is still being done to  test all, according to current known pricisions with available equipement. Although the greater precision of LISA may be needed to further validate GR or one of the other.

Forget what you were told earlier. LISA will be less sensitive not more, and will likely add little more than a stamp collecting catalog of 'SMBH' merger events. The crucial confirmation of either tensor or vector GW's will almost certainly have been long settled by the time it gets up and running.

18 minutes ago, beecee said:

...Need I point out that Svidzinky's has been murdered in some quarters in the opinions of some reputable experts, as per the article,...

There is NO reference, direct or indirect, to Svidzinsky's VTG in the article proper. so what are you talking about? Never mind, there is just a single reference, in the comments:
https://www.quantamagazine.org/troubled-times-for-alternatives-to-einsteins-theory-of-gravity-20180430/#comment-3905481088

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Just now, Q-reeus said:

Actually I don't think you do. Or certainly don't care to present it accurately if you do know it.

Of course I do and always present it accurately, unless now you chose to back away from your support for Svidzinsky's paper.

Quote

Forget what you were told earlier. LISA will be less sensitive not more, and will likely add little more than a stamp collecting catalog of 'SMBH' merger events. The crucial confirmation of either tensor or vector GW's will almost certainly have been long settled by the time it gets up and running

.No not according to the links I have given, and simply a baseless dismissal by yourself, in realizing once aloft, LISA will probably reinforce Einstein's GR model with even more validity then it rests on at this time,as the top rung of the tree.

Quote

There is NO reference, direct or indirect, to Svidzinsky's VTG in the article proper. so what are you talking about? Never mind, there is just a single reference, in the comments:
https://www.quantamagazine.org/troubled-times-for-alternatives-to-einsteins-theory-of-gravity-20180430/#comment-3905481088

The article includes all alternative models and mentions afew by name that are more worthy  then others. But as I mentioned, at least aLIGO and VIRGO are doing proper research and will in time reveal that model which best aligns with the observations, as opposed to probable faulty interpretations and weighted opinions by Svidzinsky in his paper. 

The main point of course is that no one of any consequence  [other then Svidzinsky]  is yet claiming that it is superior to GR, let alone accepted by the bulk of reputable mainstream academia.

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Your still wrong on sensitivity. I even gave you a relevent formula. Tell me why you would think that a detector incapable of picking up lower frequencies can possible be more sensitive than a detector that can only pick up higher frequencies when the frequency itself is directly related to the energy of that frequency ?

here is a simple formula [latex] E=hV[/latex] the energy is directly proportional to the frequency... this is a very basic formula and is well established under physics... In order for a detector to pick up weaker signals that detector MUST have sufficient sensitivity to do so. LIGO does not have the required sensitivity to pick up signals in the microhertz range that are specified in the LISA proposal link I provided earlier. The seismic interference is one factor that limits its possible sensitivity.

 Let me ask you another question seeing as your so strongly opposed to any refutation of the Vector gravity paper... If two blackholes merge would that not be significantly different that if two neutron stars collide? The reason I ask this is that the paper under discussion specifies that BH's do not exist in vector gravity. Yet one of the first GW waves detected by LIGO was a BH merger which followed all the predictions including the production of GW waves of GR. It even had the correct ringdown and final mass of the merger event.

 

 On a side note linking an article where the author is defending himself in rebuttals merrily enhanced my lack of faith in his model

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On 11/20/2018 at 9:16 PM, Strange said:

direction of Ak is now preferred and this direction becomes the time coordinate

Does that mean that essentially Gravity & time are the same thing?

And

On 11/20/2018 at 9:16 PM, Strange said:

1. Background geometry of the Universe is a fixed four dimensional Euclidean space with metric ${\delta }_{{ik}}\,=\mathrm{diag}$ (1, 1, 1, 1). Such space is completely isotropic and has no preferred directions.

Shouldn't there be a negative sign and become (1,1,1,-1) ?

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The author doesn't fully define why his sign convention doesn't follow the norm (-+++) or (+---) for his orthogonal tensor geometry. I'm still trying to follow his [latex] A_k[/latex] to understand his reasoning.

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On 12/8/2018 at 6:36 PM, studiot said:

 

So no response to my vector field question then, and we still have to go offsite to read any replies?

 

I see you are back again Q-rrrus.

but I still can't see a response to my question to you from two pages back.

This was about one of the 'axioms' stated in the paper you provided.

 

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8 hours ago, Mordred said:

 Let me ask you another question seeing as your so strongly opposed to any refutation of the Vector gravity paper... If two blackholes merge would that not be significantly different that if two neutron stars collide? The reason I ask this is that the paper under discussion specifies that BH's do not exist in vector gravity. Yet one of the first GW waves detected by LIGO was a BH merger which followed all the predictions including the production of GW waves of GR. It even had the correct ringdown and final mass of the merger event.

Exactly.....worth noting of course that BH's and EH's have been evidenced many other ways, not the least being the   "Dying Pulse Train" observed effect...http://www.indiana.edu/~geol105/images/gaia_chapter_1/death_spiral.htm

Quote

On a side note linking an article where the author is defending himself in rebuttals merrily enhanced my lack of faith in his model

Yes, particularly when cosmologists around the world associated with aLIGO and VIRGO, are researching this supposed claim, despite previous accusations by some of incalcitrance and stubborness with mainstream academia. I see that fact as quite illuminating.

 

 

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Another paper illustrating the science and research being currently undertaken...

https://arxiv.org/pdf/1802.10194.pdf

A Search for Tensor, Vector, and Scalar Polarizations in the Stochastic Gravitational-Wave Background: 1 Mar 2018

The detection of gravitational waves with Advanced LIGO and Advanced Virgo has enabled novel tests of general relativity, including direct study of the polarization of gravitational waves. While general relativity allows for only two tensor gravitational-wave polarizations, general metric theories can additionally predict two vector and two scalar polarizations. The polarization of gravitational waves is encoded in the spectral shape of the stochastic gravitational-wave background, formed by the superposition of cosmological and individuallyunresolved astrophysical sources. Using data recorded by Advanced LIGO during its first observing run, we search for a stochastic background of generically-polarized gravitational waves. We find no evidence for a background of any polarization, and place the first direct bounds on the contributions of vector and scalar polarizations to the stochastic background. Under log-uniform priors for the energy in each polarization, we limit the energy-densities of tensor, vector, and scalar modes at 95% credibility to Ω T 0 < 5.6 × 10−8 , Ω V 0 < 6.4 × 10−8 , and Ω S 0 < 1.1 × 10−7 at a reference frequency f0 = 25 Hz.

 

Discussion: 

 The direct measurement of gravitational-wave polarizations may open the door to powerful new tests of gravity. Such measurements largely depend only on the geometry of a gravitational wave’s strain and its direction of propagation, not on the details of any specific theory of gravity. Recently, the Advanced LIGO-Virgo observation of the binary black hole merger GW170814 has enabled the first direct study of gravitational-wave polarizations [4, 15]. While LIGO and Virgo are limited in their ability to discern the polarization of gravitational-wave transients, the future construction of additional detectors, like KAGRA [75] and LIGO-India [76], will help to break existing degeneracies and allow for increasingly precise polarization measurements. Long-duration signals offer further opportunities to study gravitational-wave polarizations. Detections of continuous sources like rotating neutron stars [44, 45] and the stochastic background [42] will offer the ability to directly measure and/or constrain gravitational-wave polarizations, even in the absence of additional detectors. In this Letter, we have conducted a search for a generically-polarized stochastic background of gravitational waves using data from Advanced LIGO’s O1 observing run. Although we find no evidence for the presence of a background (of any polarization), we have succeeded in placing the first direct upper limits (listed in Table I) on the contributions of vector and scalar modes to the stochastic background.

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Well I for one cannot fathom how his 85% dark matter, 15% baryonic matter, universe doesn't instantly collapse at time of the BB. His negative energy gravity doesn't account for the detail that gravity is a vector that leads towards mass. I don't really buy his longitudinal component of gravity as being the source of DE. Particularly since the amount of DM and baryonic matter has an equation of state of w=0. He uses the argument that the gravitons generate positive pressure to give an equivalent radiation pressure term as the FLRW metric however in this case this pressure would reduce as the universe expands.

 I won't get into the significant differences his matter % would have on the CMB temperatures...

 

 

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On 1/7/2019 at 9:32 PM, Mordred said:

 Your still wrong on sensitivity. I even gave you a relevent formula....

I knew your understanding back there was quite wrong, but had to search around to find simple formulae clearly proving it. Check out the expression for energy transport rate (i.e. power density) for a plane monochromatic GW under 'Energy transport' here:
http://www.tapir.caltech.edu/%7Eteviet/Waves/gwave_details.html

Clearly no dependency on frequency, just ~ h^2. In complete analogy to the dependence on square of E field for power density of a plane monochromatic EM wave owing to an electric quadrupole oscillator. For instance compare eqn (76) to (77) p22 here:
www.phys.lsu.edu/~jarrell/COURSES/ELECTRODYNAMICS/Chap9/chap9.pdf
No unphysical f^2 factor tacked on there either. (That power always goes as E^2 or H^2 for an EM wave is independent of source multipole moment)
So what GW 'power density' is it that varies as f^2h^2? I don't particularly care since it has zilch to do with what actually matters re detection - strain amplitude. However because it is for whatever arcane reason actually sometimes used as a 3rd 'measure of detector sensitivity', one can guess it refers to a hypothetical 'accessible power density'. Based on some peculiar criteria evidently of some academic interest. Here is a nice site with a calculator to compare the two actually useful, non-misleading sensitivity criteria:
http://gwplotter.com/

On 1/7/2019 at 9:32 PM, Mordred said:

 Tell me why you would think that a detector incapable of picking up lower frequencies can possible be more sensitive than a detector that can only pick up higher frequencies when the frequency itself is directly related to the energy of that frequency ?

Last part is wrong - see above. And what is the point in trying to compare sensitivity of one detector way outside its design bandwidth with another one in the middle of its bandwidth?

On 1/7/2019 at 9:32 PM, Mordred said:

here is a simple formula E=hV the energy is directly proportional to the frequency... this is a very basic formula and is well established under physics...

What does the Planck relation between energy and frequency for a single photon have to do with power density in classical unquantized GW's? Nothing. They are unrelated quantities. Random stabs are not making you look good.

On 1/7/2019 at 9:32 PM, Mordred said:

 In order for a detector to pick up weaker signals that detector MUST have sufficient sensitivity to do so. LIGO does not have the required sensitivity to pick up signals in the microhertz range that are specified in the LISA proposal link I provided earlier.

See above. Irrelevant comparisons are just that - irrelevant.

On 1/7/2019 at 9:32 PM, Mordred said:

 Let me ask you another question seeing as your so strongly opposed to any refutation of the Vector gravity paper...

Don't distort my position! Which has consistently been here and elsewhere that Svidzinsky's VTG lists a range of potential advantages compared to GR or similar alternatives, but that the crucial decider will be nature. The still unresolved issue of actual GW mode type. I jumped in here to a thread now vacated by the OP, to provide useful links to articles not previously covered. A waste of time in hindsight given the continued almost universal negativity in response. So I learn about how it is to be even slightly non-mainstream at ScienceForums.net the hard way.

On 1/7/2019 at 9:32 PM, Mordred said:

 If two blackholes merge would that not be significantly different that if two neutron stars collide? The reason I ask this is that the paper under discussion specifies that BH's do not exist in vector gravity. Yet one of the first GW waves detected by LIGO was a BH merger which followed all the predictions including the production of GW waves of GR. It even had the correct ringdown and final mass of the merger event.

I'm not comfortable with everything Svidzinsky advocates - his rather peculiar NS EOS that supposedly allows much larger than usual masses being one.
Anyway, try searching for 'evidence of ring down echoes in black hole merger events' or similar. There are papers out there claiming GR is already in trouble because the detailed merger waveforms hint against pure BH-BH mergers.

On 1/7/2019 at 9:32 PM, Mordred said:

 On a side note linking an article where the author is defending himself in rebuttals merrily enhanced my lack of faith in his model

Given your own slew of mistaken and/or misdirected notions here, I have little faith in your lack of faith.

On 1/7/2019 at 9:32 PM, Mordred said:

 

 

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Well regardless of your opinion I see little value in his article. I formed my own opinion of it via my own reading and study of his article. I am already familiar with the GW plotter site. As far as sensitivity goes I can literally get you papers that also state that LISA would be more sensitive. One of  those papers contains the original formula I provided. The paper itself is specific to a lecture  on GW waves and contained that rough [latex] 10^10[/latex] back of the envelope calculation.

Here is NASA'a quick rundown on its precision.

"These signals are extremely small and require a very sensitive instrument to detect. For example, LISA aims to measure relative shifts in position that are less than the diameter of a helium nucleus over a distance of a million miles, or in technical terms: a strain of 1 part in 1020 at frequencies of about a millihertz. "

https://lisa.nasa.gov/

In essence it follows precisely what I am stating. The detector will be able to detect a change many orders more fine that LIGO will. This isn't a mistake. Simple logic should tell you that if the signal strength is many orders weaker it will take a more sensitive detector to pick up that signal.

 A simple analogy is that if you have two digital multimeters and look at the specifications. The multimeter that that measure a microvolt will be more sensitive than one that can only pick up the Millivolts range. But hey if you wish to buy that low grade DMM feel free lol.

Its also a simple logic that a signal with a stronger radiated power will be easier to detect....the second formula directly correlates to that radiated energy. Obviously you will not grasp the relation between frequency and the energy of the signal.

 

 

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3 hours ago, Q-reeus said:

Don't distort my position! Which has consistently been here and elsewhere that Svidzinsky's VTG lists a range of potential advantages compared to GR or similar alternatives, but that the crucial decider will be nature. The still unresolved issue of actual GW mode type. I jumped in here to a thread now vacated by the OP, to provide useful links to articles not previously covered. A waste of time in hindsight given the continued almost universal negativity in response. So I learn about how it is to be even slightly non-mainstream at ScienceForums.net the hard way.

I haven't distorted anything.
In fact I have repeated offered you discussion about fundamental assumption or 'axioms' proposed by Svidzinsky
Discussion which you have steadfastly avoided.

Added to attitude like that displayed in the above quote you are likely to receive negative responses anywhere.

Further I observe that many of my earlier posts in this thread welcomed both the OP (who has now let us) and the subject here for adult debate, not playgrund catcalls.

Edited by studiot
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8 hours ago, Q-reeus said:

A waste of time in hindsight given the continued almost universal negativity in response. So I learn about how it is to be even slightly non-mainstream at ScienceForums.net the hard way.

The so called "continued universal negativity" that you imagine apparently is not just peculiar to this science forum. Why are you afraid of questions? Why should not any alternative hypothetical that has not been validated, not be made to run the gauntlet? Why are you opposed to let the scientific methodology take its course? Have you communicated with Svidzinsky again?

In fact the facts are entirely opposite to what you imagine, here and everywhere else, as the many links including those from aLIGO continually show. His non peer reviewed paper is being researched to the very best of what current technology allows

Quote

 There are papers out there claiming GR is already in trouble because the detailed merger waveforms hint against pure BH-BH mergers.

There are papers out there that hypothesise many amazing, and speculative scenarios. Nothing wrong with that per se, as that is how science progresses. Most though die natural deaths, forever lost in cyber space. And of course as we all know, due to the great successes of GR, it is also often a target for cranks and other assorted anti mainstream baseless accusations.

Quote

Given your own slew of mistaken and/or misdirected notions here, I have little faith in your lack of faith.

Your actual lack of faith appears to be focused on the entire physics community in general and against many professionals. To repeat my questions....Do you doubt that this paper is being actively researched? Are you concerned that running the gauntlet may reveal some shortcomings? 

And of course as has been logically pointed out to you, the LISA experiment when aloft, will in many respects logically surpass our ground based detectors.

 

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6 hours ago, Mordred said:

Well regardless of your opinion I see little value in his article. I formed my own opinion of it via my own reading and study of his article. I am already familiar with the GW plotter site. As far as sensitivity goes I can literally get you papers that also state that LISA would be more sensitive. One of  those papers contains the original formula I provided. The paper itself is specific to a lecture  on GW waves and contained that rough 1010 back of the envelope calculation.

Here is NASA'a quick rundown on its precision.

"These signals are extremely small and require a very sensitive instrument to detect. For example, LISA aims to measure relative shifts in position that are less than the diameter of a helium nucleus over a distance of a million miles, or in technical terms: a strain of 1 part in 1020 at frequencies of about a millihertz. "

https://lisa.nasa.gov/

In essence it follows precisely what I am stating. The detector will be able to detect a change many orders more fine that LIGO will. This isn't a mistake. Simple logic should tell you that if the signal strength is many orders weaker it will take a more sensitive detector to pick up that signal.

 A simple analogy is that if you have two digital multimeters and look at the specifications. The multimeter that that measure a microvolt will be more sensitive than one that can only pick up the Millivolts range. But hey if you wish to buy that low grade DMM feel free lol.

Its also a simple logic that a signal with a stronger radiated power will be easier to detect....the second formula directly correlates to that radiated energy. Obviously you will not grasp the relation between frequency and the energy of the signal.

 

 

LISA more sensitive - in it's own bandwidth of operation? Well obviously. Apples and oranges again. If on the other hand you are again insisting on applying that arcane third criteria for sensitivity while excluding the other two, that's your choice. The remainder of your post there is unfortunately too confused to be worth further replying to. In essence I sense an unwillingness to concede when proven wrong earlier on several quite mistaken and/or totally irrelevant claims.

5 hours ago, studiot said:

I haven't distorted anything.
In fact I have repeated offered you discussion about fundamental assumption or 'axioms' proposed by Svidzinsky
Discussion which you have steadfastly avoided.

Added to attitude like that displayed in the above quote you are likely to receive negative responses anywhere.

Further I observe that many of my earlier posts in this thread welcomed both the OP (who has now let us) and the subject here for adult debate, not playgrund catcalls.

First, please note I didn't carte blanche tar everyone with the same brush. Second, your own words here seem to be encouraging further negative scoring! Go check the continued hostility from one poster here in particular, who keeps up a barrage of negative commentary yet without incurring any negative scoring on his part. Interesting - no?

Now, wrt your 'axioms' issues, on checking back to your first post here, I note you stated the following:
"I was particularly interested in his distinction between 'vector' and 'tensor' (midway down the abstract) so my first task is to find out what he means by this, as tensors are technically vectors but only some vectors are tensors and GR relies on this."

That has it backwards - vectors are a rank 1 subset of tensors.
I note on p2 here you complained: "So no response to my vector field question then, and we still have to go offsite to read any replies?"

But I found no earlier specific question just a vague appeal for discussion on it. If the well structured manuscript itself is not sufficiently clear for your needs, consider emailing the author directly for further expert clarification. I'm a layman btw not claiming expert understanding of it's content.

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https://en.wikipedia.org/wiki/Laser_Interferometer_Space_Antenna#Other_gravitational-wave_experiments

Previous searches for gravitational waves in space were conducted for short periods by planetary missions that had other primary science objectives (such as Cassini–Huygens), using microwave Doppler tracking to monitor fluctuations in the Earth-spacecraft distance. By contrast, LISA is a dedicated mission that will use laser interferometry to achieve a much higher sensitivity.[citation needed] Other gravitational wave antennas, such as LIGO, VIRGO, and GEO 600, are already in operation on Earth, but their sensitivity at low frequencies is limited by the largest practical arm lengths, by seismic noise, and by interference from nearby moving masses. Thus, LISA and ground detectors are complementary rather than competitive, much like astronomical observatories in different electromagnetic bands (e.g., ultraviolet and infrared)

 

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Simple fact is that ground based antennas will never be sensitive below 1 hertz due to seismic interference largely. Space antennas are free from this constraint and can achieve much lower frequencies [latex] 10^-4[/latex] to [latex] 10^-1[/latex]. Sensitivity involves how an antenna resonates with a frequencies amplitude. The other factor involved is noise levels. (signal to noise ratio). Some of those we have already mentioned. Now that being said LISA will be more sensitive at lower frequencies however will lose sensitivity at larger frequencies. As I previously mentioned the arm length is one of the criteria. This is part of the response to a given signal.

For example the dimensionless amplitude h of a GW wave upon a (I will use a Michelson and Morley detector (most common example in documentation  ad textbooks)is given by

[latex] h=2\frac{\delta L}{L}[/latex] which is also the amount of strain.  The path length difference between the two arms then becomes [latex]\delta L=2(\delta L_1- \delta L_2)[/latex] or shortly [latex] h=\frac{\delta L}{L}[/latex]then there is the incident angel and what percentage of the waveform is occurring. This means the latter formula is further modified by [latex] h=\frac{\delta L}{L}=h sinc(\frac{2\pi L}{\lambda})[/latex] you can find these formulas in numerous articles discussing LIGO or LISA detectors.

 However I will save you the trouble and simply post the reference I used to write this particular post. see chapter 4 of how LISA calculates its sensitivity. The above formulas are from that chapter....They are largely the same in any laser interferometer article...

https://lisa.nasa.gov/archive2011/Documentation/sts_1.04.pdf

 

 

Edited by Mordred
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19 minutes ago, Q-reeus said:

First, please note I didn't carte blanche tar everyone with the same brush. Second, your own words here seem to be encouraging further negative scoring! Go check the continued hostility from one poster here in particular, who keeps up a barrage of negative commentary yet without incurring any negative scoring on his part. Interesting - no?

I find it far more interesting re your own negative comments on mainstream science and GR in general, and afterall this is the mainstream section.

 

 

Edited by beecee
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3 hours ago, Mordred said:

Simple fact is that ground based antennas will never be sensitive below 1 hertz due to seismic interference largely. Space antennas are free from this constraint and can achieve much lower frequencies 104 to 101 . Sensitivity involves how an antenna resonates with a frequencies amplitude. The other factor involved is noise levels. (signal to noise ratio). Some of those we have already mentioned. Now that being said LISA will be more sensitive at lower frequencies however will lose sensitivity at larger frequencies. As I previously mentioned the arm length is one of the criteria. This is part of the response to a given signal.

For example the dimensionless amplitude h of a GW wave upon a (I will use a Michelson and Morley detector (most common example in documentation  ad textbooks)is given by

h=2δLL which is also the amount of strain.  The path length difference between the two arms then becomes δL=2(δL1δL2) or shortly h=δLL then there is the incident angel and what percentage of the waveform is occurring. This means the latter formula is further modified by h=δLL=hsinc(2πLλ) you can find these formulas in numerous articles discussing LIGO or LISA detectors.

 However I will save you the trouble and simply post the reference I used to write this particular post. see chapter 4 of how LISA calculates its sensitivity. The above formulas are from that chapter....They are largely the same in any laser interferometer article...

https://lisa.nasa.gov/archive2011/Documentation/sts_1.04.pdf

 

In line with the excellent information that you have been forthcoming with, do you, or can the scientists involved with these detectors know what frequency we would need to observe to indicate "ripples"  from the BB itself? 

Also if drawing a long bow, and we assume this V4 gravity paper is all that its proponents say it is, and the vector modes are confirmed in line with the paper, how would this, could this over ride the preposterous "no BH's proposals" it also claims, taking into account that the effects on spacetime we see, that can only be explained by BH's, the observational verifications of "dying pulse trains", the 10 observations so far that just happen to align with BH collision templates, and of course the fact that when any Schwarszchild radius is reached, it gives no other choice then  further total collapse, at least up to the quantum/Planck level. In other words, typical GR type BH's.

 

Edited by beecee
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I've run across some theoretical calc's for the BB GW waves but will have to dig them up. Hopefully I can locate them again

located a paper by Kip Thorne see section 9.1

https://arxiv.org/pdf/gr-qc/9506086.pdf

whether or not LISA will b able to detect the primordial GW waves according to Kip Thorne will depend on whether the event will generate a frequency band of [latex] 10^{-14} [/latex] however according to that same paper the odds aren't great as according to his research on the CMB (references in that paper) the frequency band could be as low as [latex] 10^{-18}[/latex]

It would be impossible for LIGO to detect them or any other ground based detector however LISA has an extremely remote chance judging from this paper.

 

Edited by Mordred
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