Gravity Waves

[Maxila]

Before I came to this site today I just finished reading this:

After 11 years, physicists must rethink gravitational waves
http://www.extremetech.com/extreme/215169-after-11-years-physicists-must-rethink-gravitational-waves

"Scientists working at the Parkes radio telescope have announced that after 11 years of searching for evidence of gravitational waves, their search has come up empty...

...Some scientists have previously claimed to have detected gravitational waves, but those findings are not widely accepted. Physicists aren’t yet wavering on the idea that gravitational waves exist, and for now the focus will remain on how to detect them, and what to do with them after that."

 

[brucep]

That is right, in case we want to keep GR alive. Truthfully there is nothing like GR variety GW, its preposterous, the biggest hindrance to QGT/unification is the inability of key people to shake off GR, so IMNSHO GW of non GR variety will be detected, it makes sense, and then a very big hard look will be taken on GR and soon after we will have a workable sound unified theory. A decade maximum, before 2025..It will become untenable to sustain GR, if we do not get GR variety GW, so some fireworks and nasty stuff would be there.

Recall that question some popscience guy asked about Laura Mercini paper...then wtf we were looking for if no BH...

That's it huh? "All the knowledge in the world is of no use to fools". The Eagles, Don Henley. You're a fool and should be sanctioned for making so many bullshit nonsense comments and insisting you know what you're talking about. Go away goofball.

 

[brucep]

Before I came to this site today I just finished reading this:

After 11 years, physicists must rethink gravitational waves
http://www.extremetech.com/extreme/215169-after-11-years-physicists-must-rethink-gravitational-waves

"Scientists working at the Parkes radio telescope have announced that after 11 years of searching for evidence of gravitational waves, their search has come up empty...

...Some scientists have previously claimed to have detected gravitational waves, but those findings are not widely accepted. Physicists aren’t yet wavering on the idea that gravitational waves exist, and for now the focus will remain on how to detect them, and what to do with them after that."

Lots of bullshit in the first paragraph. These physicists must have forgot to review all the evidence before they started their search. Probably the poor discussion originates with the science journalist. Taylor and Hulse received the Noble in physics. It's considered a test for general relativity. They have evidence for 41 years of monitoring the orbits of the binary pulsars.

 

[brucep]

Can anyone claim that he can convince an ordinary person about what is spacetime ? It drags but it does not resist, it has curvature but its no circle or sphere of anything, it gets ripple but it is no waterline or liquid like or foam like or solid like or air like or plasma like. Its is no matter but has certain mind boggling properties.

Coming to GW, after the grand success of GP-B, where the dragging of spacetime was measured, it was the matter of the time only that the GW was measured directly.

Its a different thing that GR is in principle a single body solution, it miserbaly fails in (our abilities to solve, may be) tackling multi body distortions in the spacetime, even to solve the Mercury precession, the poor Mercury was approximated to nought, and GW is not a single body phenomenon (unlike GP-B), it requires two to create the acceleration and thus the GW. Lets see.

You're unapproachable towards these subjects. You're just making a fool of yourself. Since you don't have a clue about the actual literature you should just shut up. You're not an expert much less a knowledgeable lay person. Give it a rest.

 

[brucep]

About LISA, with such a high required sensitivity, I was wondering how they 'get around' solar light pressure moving the probes out of alinement with each other?
My very non-expert guess...their 'looking' for a rhythmic pattern in the observation and not a constant movement...like I said, I'm no expert.

I'm just speculating that the Suns radiation pressure at those coordinates, freefall orbit around the earth, can be accounted for if necessary. Maybe ignored as an infinitesimal? Maybe some continious positioning program. Seems that would be required.

 

[paddoboy]

If GW's are detected, and it would not be GR's variety, the one thing that can be guaranteed is no quantum aspects of such will ever be observed. Unlike with light.

Great little video! Quite reasonably simply and sensibly explained.
The part that interested me was about a 1/3 of the way through when he spoke of quanta of light, in normal circumstances, that are so numerous, that we are naturally unable to distinguish it from the wave nature of light.
I certainly do not though see that or any part of the video as invalidating GW's at all, including the GR variety. In fact the part I refer to, I see as supporting that.

 

[paddoboy]

That is right, in case we want to keep GR alive. Truthfully there is nothing like GR variety GW, its preposterous, the biggest hindrance to QGT/unification is the inability of key people to shake off GR, so IMNSHO GW of non GR variety will be detected, it makes sense, and then a very big hard look will be taken on GR and soon after we will have a workable sound unified theory. A decade maximum, before 2025..It will become untenable to sustain GR, if we do not get GR variety GW, so some fireworks and nasty stuff would be there.

Recall that question some popscience guy asked about Laura Mercini paper...then wtf we were looking for if no BH...

Actually the only preposterous thing are your totally unsupported and unevidenced claims. Your use of the "IMNSHO" certainly fits you and other ego inflated anti science cranks to a "T".
I would also add the biggest hindrance to reasonable discussions of science in general, is your continued anti GR rants, particularly in light of the demolishment of that irresponsible stupid Black Neutron star paper that rajesh dared to foister on the scientific community.
As you should be aware, the very nature of gravitational radiation, and how sensitive our instruments need to be to detect them, makes actually directly discovering these final validation of GR difficult.
The search will and should continue, and perhaps eLISA may have that necessary sensitivity to directly detect them.
Still most reputable sensible scientists do accept the the Hulse-Taylor Pulsar findings as ample proof.

 

[paddoboy]

Before I came to this site today I just finished reading this:

After 11 years, physicists must rethink gravitational waves
http://www.extremetech.com/extreme/215169-after-11-years-physicists-must-rethink-gravitational-waves

"Scientists working at the Parkes radio telescope have announced that after 11 years of searching for evidence of gravitational waves, their search has come up empty...

...Some scientists have previously claimed to have detected gravitational waves, but those findings are not widely accepted. Physicists aren’t yet wavering on the idea that gravitational waves exist, and for now the focus will remain on how to detect them, and what to do with them after that."

Yep, I read that at physorg.
The obvious question is that the Parkes Radio telescope is just that. I certainly give them all the cudos in the world for their valiant attempts to detect gravitational radiation, but the question that should be asked is, in reality realizing the sensitivity of detecting such phenomena, were they ever in the hunt? I don't believe so.

BTW, I have visited the Parkes Radio Telescope, on three occasions now, as it is a nice 4.5 hr drive of around 360kms from where I am, with quite a few nice Motels in the area.

 

[danshawen]

Prove me wrong.

I'll write it just one more time, with emphasis on the part you missed, so that it sinks in:

Relativity states that no experiment may be performed that would allow measurement of an absolute velocity (or in the case of gravity waves, absolute acceleration) , with respect to 'spacetime', 'spacetime warpage', or anything else that is related to the curvature of 'spacetime.'

The explanation for why this has been missed is related to Minkowski's insistence on corrupting General Relativity with ideas about interval invariance, and Euclidean solid geometry applied to the inertialess, massless, reactionless medium of relativistic 'spacetime', which is actually only 'time'. Lorentz contraction of a mass can and has been measured locally at the LHC and at other colliders. Curvature of space as it relates to gravity waves is a different animal altogether because when you and your local instruments are immersed in it, everything related to space and time will appear for all intents and purposes to be at rest, before, during, and after the passage of a gravity wave.

Notice, I'm not saying that gravity waves cannot be detected; only that they cannot be detected by instrumentation that is strictly local, like a resonant mass or interferometry apparatus. That would be like restricting relativity to a single observer. Not happening. Ever.

QED.

 

[brucep]

I'm just speculating that the Suns radiation pressure at those coordinates, freefall orbit around the earth, can be accounted for if necessary. Maybe ignored as an infinitesimal? Maybe some continious positioning program. Seems that would be required.

This is wiki on LISA.
https://en.m.wikipedia.org/wiki/Evolved_Laser_Interferometer_Space_Antenna
Scroll down to "see also" and click on the proposed Big Bang Observer.
Check this plan out.
https://dcc.ligo.org/public/0002/G0900426/001/G0900426-v1.pdf
Experimental cosmological physics. Wow.

 

[danshawen]

Paddoboy's example of the Hulse-Taylor binary gravity wave detection is the best example so far of gravity wave detection by means of comparing orbital decay to that predicted by GR. The periastron of the pair is analogous to the GR solution to the perihelion of Mercury. As the pair approach each other, significant gravity wave energy is released causing the orbits to decay, and agreement with the prediction of GR has been very close over the span of several decades of observation.

Notice that in this case, observation of the neutron star pulsar time intervals are used as one would use a distant clock AT THE EXACT LOCATION OF THE GENERATION OF THE GRAVITY WAVES some 21,000 ly distant, and they are being observed and compared to local, presumed undilated time in our vicinity. This means of detecting gravity waves and their effects will work every time.

Now imagine that except for our local gravity wave detectors, we are blind. Would we ever see or detect so much as a ripple in spacetime as a result of this dance? Our instruments may expand and contract; time may dilate and undilate; but unless you have some reference of time or distance or both from near where the gravity wave originated, what your instruments will detect (or in this case, "not detect") is the same thing that an observer in free fall relative motion to anything else ever sees locally, which is NO relative expansion or contraction, NO relative time dilation, because there is really nothing else to compare your measurements to. It's like expecting to measure a length with a meter stick by observing only one end of the measurement, or trying to mark time in terms of a single instant rather than an interval between two instants

 

[danshawen]

This is wiki on LISA.
https://en.m.wikipedia.org/wiki/Evolved_Laser_Interferometer_Space_Antenna
Scroll down to "see also" and click on the proposed Big Bang Observer.
Check this plan out.
https://dcc.ligo.org/public/0002/G0900426/001/G0900426-v1.pdf
Experimental cosmological physics. Wow.

Wow, sure.

I do like the fancy orbit. That configuration could turn out to be useful for other reasons I can easily think of.

LISA is really just another one-observer gravity wave detector in free fall around the Sun, just like Earthbound variations of the same instruments, and because of that, another costly null gravity wave experiment in progress, IMHO. I wouldn't fund or launch it until or unless LIGO pulls it off. I predict, it most certainly will not.

 

[paddoboy]

But it's really just another one-observer gravity wave detector in free fall around the Sun, just like Earthbound variations of the same instruments, and because of that, another null gravity wave experiment in progress, IMHO.

Actually, the more of these "just another" gravitational wave detectors and other probes that are aloft the better. Far better than spending money on non scientific and non humanist disciplines like militaristic defence and such.
Wouldn't it be great if NASA, ESA Roscosmos and the other space orginizations could carry on unhindered by short sighted ignorant politicians.

And real Dansharwen, your negativity on such projects is only breached by your indignant angst against the physicists/cosmologists behind all these worthwhile science endeavours.........Even if they do not achieve what originally designed for...there are no bad scientific experiments.

 

[danshawen]

there are no bad scientific experiments.

Correct, as usual.

 

[paddoboy]

Correct, as usual.

My friend the god and his "IMNSHO" would strike you down for such a blasphemous statement.
And on that point he would be right.

Paddoboy's example of the Hulse-Taylor binary gravity wave detection is the best example so far of gravity wave detection by means of comparing orbital decay to that predicted by GR. The periastron of the pair is analogous to the GR solution to the perihelion of Mercury. As the pair approach each other, significant gravity wave energy is released causing the orbits to decay, and agreement with the prediction of GR has been very close over the span of several decades of observation.

Being around 23,000 L/Years distant and your mention of time dilation, I'm not sure I understand properly, suffice to say once again, that all frames of references are as valid and as real as each other.

 

[brucep]

This is wiki on LISA.
https://en.m.wikipedia.org/wiki/Evolved_Laser_Interferometer_Space_Antenna
Scroll down to "see also" and click on the proposed Big Bang Observer.
Check this plan out.
https://dcc.ligo.org/public/0002/G0900426/001/G0900426-v1.pdf
Experimental cosmological physics. Wow.

This power point is on the BBO proposal.
https://dcc.ligo.org/public/0002/G0900426/001/G0900426-v1.pdf

 

[cosmictotem]

If we don't find gravity waves will we have to change something about Physics?

Wouldn't that only mean there are things in the Universe beyond the powers of our detection? Since our senses, and by extension, our technology, is limited in its reach due to our nature as a particular existent, shouldn't that be an expected fact of existence that is revealing in itself? I mean, we already know there a certain colors our eyes can't detect without technology. Why is discovering there are aspects of the Universe we can't ever directly or indirectly interact with and observe taken as such a disappointing surprise? It seems to me knowing that we can't ever directly or indirectly observe the whole Universe is an advancement in our knowledge of how the Universe works.

 

[brucep]

Wow, sure.

I do like the fancy orbit. That configuration could turn out to be useful for other reasons I can easily think of.

LISA is really just another one-observer gravity wave detector in free fall around the Sun, just like Earthbound variations of the same instruments, and because of that, another costly null gravity wave experiment in progress, IMHO. I wouldn't fund or launch it until or unless LIGO pulls it off. I predict, it most certainly will not.

You don't have a humble opinion on this stuff. Inflated, hot air, opinion is your calling card. Oh well *plonk*.

 

[brucep]

Wouldn't that only mean there are things in the Universe beyond the powers of our detection? Since our senses, and by extension, our technology, is limited in its reach due to our nature as a particular existent, shouldn't that be an expected fact of existence that is revealing in itself? I mean, we already know there a certain colors our eyes can't detect without technology. Why is discovering there are aspects of the Universe we can't ever directly or indirectly interact with and observe taken as such a disappointing surprise? It seems to me knowing that we can't ever directly or indirectly observe the whole Universe is an advancement in our knowledge of how the Universe works.

This isn't one of which you speak. Gravitational waves were first indirectly detected in 1974. Something that will most likely never be directly detected is the quantum gravity analog for gravitational waves. The predicted graviton.

 

[The God]

You're unapproachable towards these subjects. You're just making a fool of yourself. Since you don't have a clue about the actual literature you should just shut up. You're not an expert much less a knowledgeable lay person. Give it a rest.

Cool down gus, cool down! And ask your Lieutenant to control his emotions, he just can't stop 'liking' your posts. You are acting like a mainstream science fanatic, science works and furthers with questioning only and only religious fanatics quell the alternative arguments, not the scientific fraternity.

I have couple of points for your GW, these can be refuted with logic and scientific arguments, if any, without resorting to abuses.

1. Try interacting with Prof Lewis, and ask him that spacetime itself was so confusing (and was being taught incorrectly) and now what is this "ripples in the curvature of the spacetime". You can further ask him, if it is just the mathematical geometry, then how come it takes away the Gravitational Energy?

2. Although words like Intutive and non-intutive play no role in scientific exploration, but its a fact that anything which can be termed as non-intutive cannot be measured through physical disturbances? Do you think that the ripples in the "curvature of the spacetime" are intutive? Try explaining to yourslef.

3. GP-B, what did it measure? Geodetic? Frame Dragging? Was it conclusive in a sense that all assumptions were in line with and no other alternative explanation could have been given? To give you a clue see few papers and to start with think about the rotational motion of our solar system (recall that thread on Vortex?), the deviation of the results, the noise elimination.

4. I do agree on H-T paper, the nobel they got, but measuring something which requires sensitivity of the order of 1:10^20+, based on certain observations as taken of a star system which is few thousand light years away...cannot be a great confidence boosting stuff.

5. And I like the question as asked by Danshawen, Ripple means contraction/expansion with respect to what and the fulcrum?


Are we not moving towards giving certain materialistic property to spacetime ? Are we not giving a backdoor entry to Ether while keeping the GR intact? Both cannot survive together.