Listening for Gravitational Echoes of the Universe's Birth

Aug 19, 2009
This is an aerial view of the LIGO facility in Livingston, La. Credit: LIGO, courtesy of California Institute of Technology

(PhysOrg.com) -- An investigation by a major scientific group has advanced understanding of the early evolution of the universe.

An investigation by the LIGO (Laser Interferometer Gravitational-Wave Observatory) Scientific Collaboration and the Virgo Collaboration has significantly advanced our understanding the early evolution of the universe.

Analysis of data taken over a two-year period, from 2005 to 2007, has set the most stringent limits yet on the amount of gravitational waves that could have come from the Big Bang in the gravitational wave frequency band where LIGO can observe. In doing so, the gravitational-wave scientists have put new constraints on the details of how the universe looked in its earliest moments.

Much like it produced the , the Big Bang is believed to have created a flood of gravitational waves—ripples in the fabric of space and time—that still fill the universe and carry information about the universe as it was immediately after the Big Bang. These waves would be observed as the "stochastic background," analogous to a superposition of many waves of different sizes and directions on the surface of a pond. The amplitude of this background is directly related to the parameters that govern the behavior of the universe during the first minute after the Big Bang.

Earlier measurements of the cosmic microwave background have placed the most stringent upper limits of the stochastic gravitational wave background at very large distance scales and low frequencies. The new measurements by LIGO directly probe the gravitational wave background in the first minute of its existence, at time scales much shorter than accessible by the cosmic microwave background.

The research, which appears in the August 20 issue of the journal Nature, also constrains models of cosmic strings, objects that are proposed to have been left over from the beginning of the universe and subsequently stretched to enormous lengths by the universe's expansion; the strings, some cosmologists say, can form loops that produce gravitational waves as they oscillate, decay, and eventually disappear.

Gravitational waves carry with them information about their violent origins and about the nature of gravity that cannot be obtained by conventional astronomical tools. The existence of the waves was predicted by Albert Einstein in 1916 in his general theory of relativity. The LIGO and GEO instruments have been actively searching for the waves since 2002; the Virgo interferometer joined the search in 2007.

The authors of the new paper report that the stochastic background of gravitational waves has not yet been discovered. But the nondiscovery of the background described in the Nature paper already offers its own brand of insight into the universe's earliest history.

The analysis used data collected from the LIGO interferometers, a 2 km and a 4 km detector in Hanford, Washington, and a 4 km instrument in Livingston, Louisiana. Each of the L-shaped interferometers uses a laser split into two beams that travel back and forth down long interferometer arms. The two beams are used to monitor the difference between the two interferometer arm lengths.

According to the general theory of relativity, one interferometer arm is slightly stretched while the other is slightly compressed when a gravitational wave passes by.

The interferometer is constructed in such a way that it can detect a change of less than a thousandth the diameter of an atomic nucleus in the lengths of the arms relative to each other.

Because of this extraordinary sensitivity, the instruments can now test some models of the evolution of the early universe that are expected to produce the stochastic background.

"Since we have not observed the stochastic background, some of these early-universe models that predict a relatively large stochastic background have been ruled out," says Vuk Mandic, assistant professor at the University of Minnesota.

"We now know a bit more about parameters that describe the evolution of the universe when it was less than one minute old," Mandic adds. "We also know that if cosmic strings or superstrings exist, their properties must conform with the measurements we made—that is, their properties, such as string tension, are more constrained than before."

This is interesting, he says, "because such strings could also be so-called fundamental strings, appearing in string-theory models. So our measurement also offers a way of probing string-theory models, which is very rare today."

"This result was one of the long-lasting milestones that LIGO was designed to achieve," Mandic says. Once it goes online in 2014, Advanced LIGO, which will utilize the infrastructure of the LIGO observatories and be 10 times more sensitive than the current instrument, will allow scientists to detect cataclysmic events such as black-hole and neutron-star collisions at 10-times-greater distances.

"Advanced LIGO will go a long way in probing early universe models, cosmic-string models, and other models of the stochastic background. We can think of the current result as a hint of what is to come," he adds.

"With Advanced LIGO, a major upgrade to our instruments, we will be sensitive to sources of extragalactic gravitational waves in a volume of the universe 1,000 times larger than we can see at the present time. This will mean that our sensitivity to gravitational waves from the Big Bang will be improved by orders of magnitude," says Jay Marx of the California Institute of Technology, LIGO's executive director.

"Gravitational waves are the only way to directly probe the universe at the moment of its birth; they're absolutely unique in that regard. We simply can't get this information from any other type of astronomy. This is what makes this result in particular, and gravitational-wave astronomy in general, so exciting," says David Reitze, a professor of physics at the University of Florida and spokesperson for the LIGO Scientific Collaboration.

"The scientists of the LIGO Scientific Collaboration and the Virgo Collaboration have joined their efforts to make the best use of their instruments. Combining simultaneous data from the LIGO and Virgo interferometers gives information on gravitational-wave sources not accessible by other means. It is very suggestive that the first result of this alliance makes use of the unique feature of gravitational waves being able to probe the very early . This is very promising for the future," says Francesco Fidecaro, a professor of physics with the University of Pisa and the Istituto Nazionale di Fisica Nucleare, and spokesperson for the Virgo Collaboration.

Maria Alessandra Papa, senior scientist at the Max Planck Institute for Gravitational Physics and the head of the LSC overall data analysis effort adds, "Hundreds of scientists work very hard to produce fundamental results like this one: the instrument scientists who design, commission and operate the detectors, the teams who prepare the data for the astrophysical searches and the data analysts who develop and implement sensitive techniques to look for these very weak and elusive signals in the data."

The LIGO project, which is funded by the National Science Foundation (NSF), was designed and is operated by Caltech and the Massachusetts Institute of Technology for the purpose of detecting , and for the development of gravitational-wave observations as an astronomical tool.

Research is carried out by the LIGO Scientific Collaboration, a group of 700 scientists at universities around the United States and in 11 foreign countries. The LIGO Scientific Collaboration interferometer network includes the LIGO interferometers and the GEO600 interferometer, which is located near Hannover, Germany, and designed and operated by scientists from the Max Planck Institute for Gravitational Physics, along with partners in the United Kingdom funded by the Science and Technology Facilities Council (STFC).

The Virgo Collaboration designed and constructed the 3 km long Virgo interferometer located in Cascina, Italy, funded by the Centre National de la Recherche Scientifique (France) and by the Istituto Nazionale di Fisica Nucleare (Italy). The Virgo Collaboration consists of 200 scientists from five Europe countries and operates the Virgo detector. Support for the operation comes from the Dutch-French-Italian European Gravitational Observatory Consortium. The LIGO Scientific Collaboration and Virgo work together to jointly analyze data from the LIGO, Virgo, and GEO interferometers.

The next major milestone for LIGO is the Advanced LIGO Project, slated to begin operation in 2014. Advanced LIGO will incorporate advanced designs and technologies that have been developed by the LIGO Scientific Collaboration. It is supported by the NSF, with additional contributions from the U.K.'s STFC and Germany's Max Planck Society.

More information: The paper is entitled "An Upper Limit on the Amplitude of Stochastic Gravitational-Wave Background of Cosmological Origin." www.nature.com/nature/journal/v460/n7258/full/nature08278.html

Source: California Institute of Technology (news : web)

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User comments : 60

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deatopmg
2.1 / 5 (8) Aug 19, 2009
So, after this long release basically they've found nothing! Could it be that the Big Bang theory is wrong and that we live in a more or less steady state universe?
earls
2.3 / 5 (9) Aug 19, 2009
Regardless if the Big Bang is relevant or not, it should be obvious by now that "gravitational waves" do not exist.

Of course, we'll keep getting the "it's not sensitive enough" excuse until ... ?

Such criticism is fodder for a low post rating, but honestly, what evidence do people have to the contrary?
SincerelyTwo
4.4 / 5 (7) Aug 19, 2009
earls: better to try than assume anything, besides, would you rather we waste money in war? at least this can give some answers and possibly be used for other things... who knows. I'd rather they continue regardless.
ThomasS
4.2 / 5 (5) Aug 19, 2009
Well, now that they've build a first version, it will also be easier to build the upgrade. Besides I think the evidence for gravitational waves is pretty strong. And they still might detect something before 2014.
earls
1 / 5 (4) Aug 19, 2009
You "think" the evidence is pretty strong? What evidence?!

SincerelyTwo, who's assuming? You apparently, I never remarked the projects should not continue, only that gravitational wave theory has not and most likely will not translate into reality.

The interferometers have already proven useful for discovery - consider the one in the UK that one scientist believes has revealed the fundamental fuzziness of the Universal fabric.
Noumenon
4.7 / 5 (52) Aug 19, 2009
Maybe they will detect the ether (j/k).
davesmith_au
2.8 / 5 (8) Aug 19, 2009
There is nor has there ever been any "evidence" of gravitational waves. There has long been a theory, which now that we've been actively searching for 7 years and detected zero gravitational waves, is looking pretty shaky at best.

Taxpayers should be up in arms that this folly is to continue.

Cheers, Dave Smith.
lomed
4.3 / 5 (4) Aug 19, 2009
There is nor has there ever been any "evidence" of gravitational waves.

From the wikipedia article on gravitational waves ( http://en.wikiped...nal_wave ) :
The measurements on the Hulse-Taylor system have been carried out over more than 30 years. It has been shown that the gravitational radiation predicted by general relativity allows these observations to be matched within 0.2 percent. In 1993, Russell Hulse and Joe Taylor were awarded the Nobel Prize in Physics for this work, which was the first indirect evidence for gravitational waves.
This evidence may be indirect, but unless there is a better alternative explanation for this result, it is evidence supporting the existence of gravitational waves. Since the observations match what is predicted by general relativity so closely, I think it would be a rather unlikely coincidence for the cause to be something else.
Slotin
2.5 / 5 (11) Aug 19, 2009
AWT model doesn't say, gravitational waves doesn't exists - they're just dispersive, so they cannot be detected at larger distance.

Why Einstein didn't believe in gravitational waves..
http://dafix.uark...eree.pdf
brant
1.8 / 5 (5) Aug 20, 2009
There is nor has there ever been any "evidence" of gravitational waves.


From the wikipedia article on gravitational waves ( http://en.wikiped...nal_wave ) :

The measurements on the Hulse-Taylor system have been carried out over more than 30 years. It has been shown that the gravitational radiation predicted by general relativity allows these observations to be matched within 0.2 percent. In 1993, Russell Hulse and Joe Taylor were awarded the Nobel Prize in Physics for this work, which was the first indirect evidence for gravitational waves.
This evidence may be indirect, but unless there is a better alternative explanation for this result, it is evidence supporting the existence of gravitational waves. Since the observations match what is predicted by general relativity so closely, I think it would be a rather unlikely coincidence for the cause to be something else.


Gravitational radiation is not waves in space/time gravity waves.

I think there are gravitons as opposed to Einsteins spacetime flippity flop.
Velanarris
2.7 / 5 (6) Aug 20, 2009
Gravity could be a decoupled field force or it could not be a field at all. We can't even determine if gravity is a push or pull based upon Einstein's visual representation of gravitational effects.

Perhaps gravity cannot be unified with the electrical forces as it isn't an electrical force itself but a combination of diverse electrical forces interacting with each other.

In any eventuality we've been completely unable to detect gravity waves, if they do exist, and as such we may want to revise our understanding of energy interaction.
Ethelred
3 / 5 (6) Aug 20, 2009
Upgrades to LIGO and other detectors such as VIRGO, GEO 600, and TAMA 300 should increase the sensitivity still further; the next generation of instruments (Advanced LIGO and Advanced Virgo) will be more than ten times more sensitive. Another highly sensitive interferometer (LCGT) is currently in the design phase. A key point is that a ten-fold increase in sensitivity (radius of 'reach') increases the volume of space accessible to the instrument by one thousand times. This increases the rate at which detectable signals should be seen from one per tens of years of observation, to tens per year.


I think this is the key point on the Wiki. It is highly unlikely that any of the detectors presently in use was going to find anything at all without a LOT of luck. Like an unknown black hole pair fairly close coalescing. The next generation will have much greater chance of finding evidence if there is any.

About all these early tests have really been good for is to develop better technology that might actually be fit the job of detecting something.

Which annoyed me when I first heard about them. Still does a bit but I suppose the stuff coming up wouldn't have been built without some sign that they could be built and made to work to specs if not actual success.

Ethelred

Sorry for the new signature. But It Needed Killun.

From QubitTamer's fake profile

Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.


Qubitwit gets the rest of August in my signature for aiming his idiocy at me. Again.
earls
not rated yet Aug 20, 2009
"a combination of diverse electrical forces interacting with each other."

Hang him.
Velanarris
2.3 / 5 (3) Aug 20, 2009
"a combination of diverse electrical forces interacting with each other."

Hang him.

Reason?
earls
not rated yet Aug 20, 2009
*Everyone* knows Gravity is its own force (with its own fields and particles) and has no relation in any way shape or form to EM. No way, no how is Gravity a compound effect of electromagnetism.

http://abstrusegoose.com/175
Ethelred
2 / 5 (3) Aug 20, 2009
I think earls is under the impression that you were making a plasma universe post. The odd this is that its davesmith_au who is the plasma universe fan on this thread.

From his profile:
Location:

Adelaide, Australia

Affiliation:

www.plasmaresources.com
www.thunderbolts.info


And he is from Australia so it wasn't his tax money that was spent on this stuff.

Ethelred

Sorry for the new signature. But It Needed Killun.

From QubitTamer's fake profile

Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.


Qubitwit gets the rest of August in my signature for aiming his idiocy at me. Again.
Velanarris
2.5 / 5 (6) Aug 20, 2009
*Everyone* knows Gravity is its own force (with its own fields and particles) and has no relation in any way shape or form to EM. No way, no how is Gravity a compound effect of electromagnetism.

http://abstrusegoose.com/175

Actually, no one knows anything about gravity. Everyone thinks about gravity but no one has any idea what or how it works.

To evidence my point feel free to measure a gravity wave or particle. The RHIC, Tevatron, LIGO, and VIRGO have been unsuccessful in doing so, so you'll be up for some prestigious awards on completion.
ben6993
2 / 5 (1) Aug 20, 2009
My guess is that inflation causes gravity. (Though what causes inflation?)
Inflation of space has been detected. Matter is mostly composed of space, and the more they look the more space they find as 'fundamental' particles get smaller. When talking about inflation of space, inflation of matter isn't normally mentioned as it is too silly a notion?

Maybe the earth really is pushing up at our feet as the rate of inflation is different within matter than the rate of inflation is when away from matter.


Deflation should imply a repulsive gravity.
JIMBO
1 / 5 (1) Aug 20, 2009
DaveSmith is right on !
Altho there has been strong, indirect evidence (Taylor-Hulse pulsar) before, LIGO is coming up on 10yrs of failed science runs to see any DIRECT evidence of grav waves. Realizing they gotta publish or perish, they have now produced two farcical studies of threshold effects; One, last year on neutron-star sphericity, and now this one. Its ludicrous to do science without proof of principle, & now they pin their hopes on the recently funded Adv.LIGO. If it does not deliver direct detection, heads will roll.
I do disagree with Dave that the taxpayers should be having a cow over LIGO. A much bigger joke that has been perpetuated on the American public for over 1/2 century, has been the farcical and hypocritical DOE/DOD programs to develop fusion for electric power generation. It swamps LIGOs costs literally by hundreds of billions of dollars, and has returned nothing but bomb design research. Wasted B$$$ continues w/congressional approval, as if the cold war is still on ??!
Where science could really deliver, would be to fund a `Manhatan Project' to track & develop systems to intercept asteroids & comets before we become dinosaurs.
Velanarris
3 / 5 (6) Aug 20, 2009
Where science could really deliver, would be to fund a `Manhatan Project' to track & develop systems to intercept asteroids & comets before we become dinosaurs
Where do you think that technology would come from?

Oh yeah, weapons research.
earls
not rated yet Aug 20, 2009
Low ratings, but no explanations as to what inaccuracies are being conveyed.
Alexa
2.6 / 5 (5) Aug 20, 2009
..everyone thinks about gravity but no one has any idea what or how it works...
Fatio de Duillier has such idea before three hundreds of years and we still need no change about it.

http://www.aether...Sage.gif
Velanarris
2.4 / 5 (5) Aug 20, 2009
..everyone thinks about gravity but no one has any idea what or how it works...
Fatio de Duillier has such idea before three hundreds of years and we still need no change about it.



http://www.aether...Sage.gif

Yep because it went right into the bin after he developed it and couldn't support it mathematically.
Alexa
3 / 5 (4) Aug 20, 2009
..it went right into the bin after he developed it and couldn't support it mathematically..
Well, exactly on the contrary...;-) So far Duillier-LeSage theory is the only model of gravity, which can explain inverse square law by pure geometry. Note that without knowledge of Newton law we couldn't derive general relativity (and it forms another "secret" postulate of general relativity, which mainstream covers before laymans to keep the superiority of relativity over Newtonian physics). And without Duillier's model the Newton gravity law is completely adhoced in the same way, like relation between potential energy and distance in derivation of Einstein equations.

If mainstream physic would follow causality of its formal derivations thoroughly, it could find Aether model as the only possible causal solution before many years already. As your comment illustrates clearly, publicity is brainwashed thoroughly in this point.
Alexa
3 / 5 (4) Aug 20, 2009
It's well known, Newton originally considered gravity inversely proportional to distance and he fighted for his opinion in many letters with Hooke, who claimed inverse square law from very beginning. Just the intervention of Fatio de Duillier aka Newton's friend forced Newton to correct and change his opinion. In fact Newton was complete troll regarding practical connections of reality. Of course this picture is completelly different from mainstream propaganda - but who cares about it?
Alexa
3 / 5 (4) Aug 20, 2009
..I think there are gravitons as opposed to Einsteins spacetime flippity flop..
I'd prefer to consider more general theory, which can explain wave particle duality even for gravity, rather then remain biased toward particular model. You can think about gravitons like about "flipity flops" thiniest possible with respect to Lie group geometry.
..gravity cannot be unified with the electrical forces as it isn't an electrical force itself but a combination of diverse electrical forces interacting with each other..
We can think about EM wave like about transversal surface wave and about gravitational wave like about bulk longitudinal wave. After then it's clear, bulk waves are just mediated by surface waves of many particles involved - so that the combination of "diverse electrical forces interacting with each other" is exactly the way, in which we can reconcile gravity with EM force - at least at conceptual level.



I presume, it can be verified in particle simulations on computers rather then via formal math, but mathematicians are rather inventive, if they know exactly, what to do. We're just at the very beginning of the final understanding, because mainstream physics spent whole last half of century by blind combinations of quantum and relativity equations, which we know already, they're inconsistent each other.
ben6993
not rated yet Aug 21, 2009
Re: "the Universe is huge system of particles under diffusions (energy density leveling), which dissolves the space-time ..."
.................


The article seems to imply that, in his mathematical model, superimposed states are unreal while collapsed states are real. And that they always stay like that, unchanging. Sometime earlier in this chain of comments, I suggested that states could change from 'unreal' to 'real'. But I was guilty of thinking of space and time separately. I grant that for spacetime there can be no change of states as it is possible to step outside spacetime in your imagination and see it as a static, immutable object. Under this model spacetime cannot dissolve? Unless it is meant that some superimposed states in time dissolve into collapsed ones?
Velanarris
2.6 / 5 (5) Aug 21, 2009
Well, exactly on the contrary...;-) So far Duillier-LeSage theory is the only model of gravity, which can explain inverse square law by pure geometry. Note that without knowledge of Newton law we couldn't derive general relativity (and it forms another "secret" postulate of general relativity, which mainstream covers before laymans to keep the superiority of relativity over Newtonian physics). And without Duillier's model the Newton gravity law is completely adhoced in the same way, like relation between potential energy and distance in derivation of Einstein equations.

So let me see if I understand you correctly. It's a big conspiracy, Newtonian physics (the basis for your pet AW hypothesis) is correct and relativity is wrong, they cover up that relativity is wrong, and you don't understand PE vs KE over distance.

Thanks for clearing that up.
Alexa
3 / 5 (6) Aug 21, 2009
...It's a big conspiracy...
Not at all, the misunderstanding and false refusal of Aether theory is rather result of collective stupidity. The refusal of perspective theories is an emergent phenomena, which is the more pronounced, the larger group of society is involved. When every member of crowd makes a single step toward wall, it crushes bones of individuals near wall. In big crowd of people just subtle negativism of every individual is sufficient for propagation of reaction, which destroys motivation of individuals to spread new theory. Instead of it, conspiration is organized action of small group of people.
Alexa
2.3 / 5 (6) Aug 21, 2009
..Newtonian physics (the basis for your pet AWT hypothesis) is correct and relativity is wrong..
AWT theory is geometrodynamical theory, it considers only wave equation (i.e. relation between mass/energy density and time/space intervals) from Newtonian mechanics. The gravitational law is ad-hoced postulate in Newton theory and relativity cannot derive it by itself. Instead of it, it borrows gravitational constant from Newton's theory.

Therefore AWT predicts the same violation for Newton law, like for general relativity. For example Casimir force is a shielding effect of gravitational waves (which manifest by photons of cosmic microwave background, so it's limited to CMB photons wavelength distance scale). Whereas Pioneer anomaly is subtle deceleration caused by dispersion of light by these gravitational waves. We can see, how violation of Newton law at small scales (Casimir force anomaly) manifests itself by deceleration at large scale (background field deceleration of Pioneer anomaly) and as such it violates equivalence principle of general relativity (Pioneer anomaly deceleration is proportional to surface, not mass of object).

In another words, when Newton theory becomes wrong, then the relativity becomes wrong as well and AWT is invariant to these violations at both cases, because it doesn't depend on both Newton law validity, both equivalence principle validity.
Alexa
2.6 / 5 (5) Aug 21, 2009
..sometime earlier in this chain of comments, I suggested that states could change from 'unreal' to 'real'..
Of course, this is what the quantum fluctuations are about. Aether is condensing and evaporating randomly in the same way, like inside of Boltzmann gas the density fluctuations are formed and disappear in certain range. In AWT whole observable Universe is single huge fluctuation - extremely unprovable one, but unavoidable due the immense amount of particles involved.

..since we have not observed the stochastic background...
This sentence sounds funny for me, because the main problem of interferometric measurements like LIGO is the separation of signal from omnipresent noise caused by gravitational waves...;-)
lomed
3 / 5 (2) Aug 21, 2009
as such it violates equivalence principle of general relativity (Pioneer anomaly deceleration is proportional to surface, not mass of object).
The (strong) equivalence principle states that the acceleration due to a uniform gravitational field is equivalent in its effects to acceleration (due to non-gravitational forces) in "flat" space-time. What AWT predicts may be different from what relativity predicts but, the effect you describe has nothing (that I know of) to do with a violation of the (strong) equivalence principle. (I do not mean that the equivalence principle is not violated in AWT (I wouldn't know); I only mean that what you describe in the post is not a violation of the principle.)
it borrows gravitational constant from Newton's theory.
Since Newton's theory of gravity has been shown to be accurate within a certain realm of observation, any more accurate theory must give the same results as Newton's theory gives in that same realm. Like all dimensionful constants, Newton's gravitational constant serves to give the correct units to the equation for gravitation (in newtonian, eisteinian, and many other theories of gravity). I find it hard to believe a theory of gravity could predict phenomena, in the newtonian realm of applicability, as well as newtonian theory does, and not include Newton's gravitational constant.
Husky
not rated yet Aug 22, 2009
I would venture to say that gravity perhaps works as a pushing force, like a macroscale version of the cassimir effect, in the sense that the matter of a large dense object such as a planet, literally occupies space, limiting the vacume fluctuations that could occur in that space, while away from that planet, vacume fluctuations have more room to play.

Virtual particals popping in and out of existence in the high energy state of deep space creates more pressure/push than in the vicinity of a planet where much energy is condensed as matter in a lower energy state, creating much less vacume particle backpressure, effectively allowing astroids to be pushed by the aether wind towards the planet, what we like to think of the planet pulling other objects using gravity but still gravity defies the Grand Unification Theory, precisely for the fact that we assume that the condensed matter of the planet of this pulling force, while perhaps we better take vacume particles as the acting agent. In this view, because the planet is made up of condensed matter in all different spin states, quantum vacume fluctuations are dampened across the full sprectrum of wave frequencies, so that gravity seems to act as an omnidirectional non selective force. Relativistic gravity effects, such as time-dilation and mass increase as experienced by a spaceship/crew flying close to lightspeed could be explained as the spaceship faster pushing against virtual particals than that they can annihilate with their counterpart, thus creating drag
Ethelred
3 / 5 (4) Aug 22, 2009
The gravitational law is ad-hoced postulate in Newton theory and relativity cannot derive it by itself. Instead of it, it borrows gravitational constant from Newton's theory.


There is noting ad-hoc about General Relativity. It was developed, pretty much, from first principles. The need for measured constants, rather than derived constants, is something ALL theories have. Including AWT. No theory has been able to produce every constant needed simply by introspection. It is HIGHLY unlikely that any theory ever will do so.

Ethelred

Sorry for the new signature. But It Needed Killun.

From QubitTamer's fake profile

Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.


Qubitwit gets the rest of August in my signature for aiming his idiocy at me. Again.
Alexa
2.6 / 5 (5) Aug 22, 2009
..The need for measured constants, rather than derived constants, is something ALL theories have. Including AWT..
I've nothing against it, every theory uses ad-hoced postulates - so why relativity proponent covers, the using inverse square law and gravity constant from Newton's theory? Such law becomes postulate like light invariance and equivalence principle, after then. It's just an example of consequential thinking.
..It is HIGHLY unlikely that any theory ever will do so...
Never ever say never...;-)
Ethelred
2.3 / 5 (3) Aug 23, 2009
- so why relativity proponent covers, the using inverse square law and gravity constant from Newton's theory?


Why shouldn't it? The constant comes from measurements, same as Newton. Since the same thing is being measured there is no reason to have a different number. The inverse square law is inherent in the geometry. It has always struck me as rather odd that Newton ever thought otherwise. My guess is that it was his excessive ego as he didn't think of it first.

Never ever say never...;-)


Who besides Sean Connery ever said never? All right lots of people but it is the principle of the thing. Of course I have said it regarding evolution vs. Creationism but that is a special case. But in this case I see a total lack of the use of the word never by me. I said EVER combined with highly unlikely.

To derive ALL constants would mean that there is only one possible universe. Which I think is a crock.

Ethelred

Sorry for the new signature. But It Needed Killun.

From QubitTamer's fake profile

Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.


Qubitwit gets the rest of August in my signature for aiming his idiocy at me. Again.
abzu
not rated yet Aug 23, 2009
Keep spending money not detecting anything and coming up with excuses for it rebranded as revised theories. Insane.
Ethelred
3 / 5 (2) Aug 24, 2009
Since they never really had any expectation of finding gravity waves with this early equipment I think you are wrong on this. IF they had a reasonable expectation of detecting gravity waves then you would have a point. These experiments were more proof of concept than anything else.

If the equipment was functioning as believed then even negative results tell us things. Not much and it is subject to future data as there is the possibility that the experiments simply weren't doing what they were supposed to be doing. Its so hard to tell when the experiment finds exactly zero and was expected to find zero.

Perhaps a large nuclear explosion with a lot of mass being dispersed over the laser grid could be used to calibrate the thing. Somehow I suspect this would not get approval. Perhaps conventional explosives would do. I still don't see that getting approval either.

Ethelred

Sorry for the new signature. But It Needed Killun.

From QubitTamer's fake profile

Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.


Qubitwit gets the rest of August in my signature for aiming his idiocy at me. Again.
Alexa
3 / 5 (4) Aug 25, 2009
Listening for Gravitational Echoes of the Universe's Birth
Concerning primordial gravitational waves, they're CMB photons itself and here's nothing to observe anymore (the primordial gravitons expanded into gravitational waves of CMB size during inflation).

The second problem is finding gravitational waves from distant quasars and black holes and I don't think, they find some.

The third problem is the finding of cases of gravitational waves shielding or focusation and such cases were detected already.

http://www.physor...399.html
Alexa
2.6 / 5 (5) Aug 25, 2009
..Keep spending money not detecting anything and coming up with excuses for it rebranded as revised theories...
There are at least two levels of dumbness:

First level is to spend money while trying to find artifacts, which cannot be observed.

Second level is to spend money while trying to find artifacts, which everyone can observe in his TV antenna.

It's not dumbness of scientists involved though, because these scientists aren't spending their money: these money are from our taxis. It's our dumbness.
Ethelred
3 / 5 (4) Aug 25, 2009
First level is to spend money while trying to find artifacts, which cannot be observed.


Which would be dumb if anyone could prove that to be the case. You certainly haven't.

Second level is to spend money while trying to find artifacts, which everyone can observe in his TV antenna.


The Cosmic Background radiation that is seen on on TVs is hardly telling us much besides showing that it exist at the specific frequencies the TV is tuned to. It tells us nothing about what directions it comes from and nothing about the other frequencies. And it has NOTHING to do gravity waves in and of themeselves. So why bring it up?

Ethelred

Sorry for the new signature. But It Needed Killun.

From QubitTamer's fake profile

Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.


Qubitwit gets the rest of August in my signature for aiming his idiocy at me. Again.
Ethelred
3 / 5 (5) Aug 26, 2009
Can you prove it?


Yes. Its electromagnetic radiation that shows up between channels and it shows only that the Cosmic Background Radiation exists. It shows nothing else and even then it took a lot of research to show the CBR was responsible for any of it.

This analogy is quite clear and straightforward.


Yet irrelevant.

? I see, I forgot - a disbelief in Aether concept again.


What is there believe since you have nothing to support it except for own opinions. When you can do the math to support you and show some actual evidence then there will be something to go on.

Now we are paying scientists for keeping them in their ignorancy - isn't it amazing?


Julianne Frys Isn't That Amazing.

I know you won't get that but I like it anyway.

You are the one that is pushing the theory. HERE and not in actual science journals. Do the math, get some help with the English and GET PUBLISHED. Then maybe there will something to your claims. In the meantime it looks no more real then the Plasma Universe fans and they are just plain full of it.

But why I'm explaining it to silly people, who are filling discussion with their "signature" all the time?


You aren't actually explaining anything to anyone because you claim you don't need math and you do.

My sig stays till the end of August. I try to keep my promises.

Unless you can convince the idiot to quit lying in his profile. He does mostly stay away while I use it so I have to say that it has been quite effective.

To spam with "signature" in such way isn't hysterical?
]

See above. It works.

It just demonstrates, QubitTamer was completelly right in this point...;-)


Is that why he disapears? Or is because I am pointing out that he lying about being a physicist?

Ethelred

Sorry for the new signature. But It Needed Killun.

From QubitTamer's fake profile

Quantum Physicist, torturer of AGW religious zealots like Ethelred because i laugh at his hysterics.


Qubitwit gets the rest of August in my signature for aiming his idiocy at me. Again.
Noumenon
4.8 / 5 (48) Aug 27, 2009
Gravitational waves have already been inferred to exist from observations [Hulse/Tayler] of the loss of such energy from binary pulsar systems, in accord with GR to great accuracy. It's not direct observation yet, but then modern experimentation is not so direct in most cases. Can the aether be observed directly in principal (?), no according to Alexa!
Galilean_Cannonball
not rated yet Aug 30, 2009
A truly hilarious and entertaining thread. No disrespect intended, but you people are funny. Presumably, assuming quantum mechanics is right, and assuming that relativity is right, (granted, two big assumptions) then the jury will remain out until there is a reconciliation between them. By the way, this is science, so when is anything in science every settled? We make assumptions, gather information, test the theories against the information gathered, refine our theories, and move on. The more information we get, the stronger, or weaker our theories become, eventually, thus far at least, paradigm shift, we start again. Unless you have something invested in any particular theory, it's to be expected. It's all grist for the mill from my perspective. More power to you all.
Velanarris
2.3 / 5 (6) Aug 30, 2009
Gravitational waves have already been inferred to exist from observations [Hulse/Tayler] of the loss of such energy from binary pulsar systems, in accord with GR to great accuracy. It's not direct observation yet, but then modern experimentation is not so direct in most cases. Can the aether be observed directly in principal (?), no according to Alexa!

Problem is the aether cannot be jsutified mathematically. Gravity waves can.
Noumenon
4.8 / 5 (47) Aug 30, 2009
agreed
Ethelred
1.8 / 5 (5) Sep 01, 2009
The fact, things like space-time or Aether cannot be observed directly being abstract concepts doesn't mean, we cannot use them in prediction of various phenomena, gravitational waves in particular.


Correct. But you can't predict anything about anything in a testable way without NUMBERS.

Do the bloody math.

From particle model of vacuum follows, whenever such environment gets more dense during inflation, for observer of transversal waves in it the space-time expands and primordial gravitons will change into photons of CMB, whereas the transversal waves (primordial gravitational waves) would collapse into CMB photons, instead.


Which is an ad hoc explanation if I have ever seen one. Do you have some math to justify that or is that exactly what it looks like. Throwing words at a problem and hoping some will stick.

Ethelred
Velanarris
3 / 5 (6) Sep 01, 2009
Correct. But you can't predict anything about anything in a testable way without NUMBERS.

Do the bloody math.
He/she/it can't do the math. It's apparent that there is NO math to AWT. AWT is a philosophical concept composed of foolhardy ideals and terrible pre-Newtonian physics.

I'm ready for the 3 1 ranks I'll get as Alexa/Slotin/Alizee dance their way into a reply that will leave more questions unanswered, and less information available than the crayon scribblings of a two year old on holiday.
Slotin
3 / 5 (6) Sep 01, 2009
..But you can't predict anything about anything in a testable way without NUMBERS....
Wrong. You canot predict anything without logics. Formal math is just a condensate of predicate logics. For example Mr. Galileo predicted the correct order of Venus phases by using of heliocentric model without formal math, thus disproving your claim by example. Darwin predicted a lotta things with theory containing no math at all. We are understanding many things without formal math at all.
Velanarris
3 / 5 (4) Sep 02, 2009
using of heliocentric model without formal math, thus disproving your claim by example.
As stated Galileo did not ignore math when he determined the heliocentric model.

Secondly Darwin's hypothesis didn't require math as evolutionary study is not a math based science. That's akin to decrying social sciences because they don't use math.

Difference is, physics is a math intensive science. If you postulate on the effects of particle interaction, you need to have the math to show that, based on current principles, the particles will actually interact.

The fact you put forth AWT as a TOE and provide no inkling of understanding of the field is insulting to people who actually put the work behind their theories. If you want to have that exemplified, take your little website, put it in thesis form and publish it. When you receive your last rejection notice feel free to tell us we're right.
Alexa
3 / 5 (6) Sep 02, 2009
..Galileo did not ignore math when he determined the heliocentric model..
He didn't use math for description of heliocentric model, Kepler and Copernicus did.
...physics is a math intensive science..

In math everything is based on predicate logics of theorems, which must be proven first. Just because physics is so math intensive, it should use the very same approach: we should made logical proof of particular model first, derivation of formulas later.

Collisions of particles inside of particle gas cannot be computed, just modeled by computer simulation. It's not my problem, formal math cannot handle it. I'm not insisting on assumption, observable Universe must remain computable. In nature we can met with many phenomena, which cannot be computed at all.

..is insulting to people who actually put the work behind their theories..
Whereas I can feel insulted by stupidity, in which formally thinking people are dealing with Aether concept, instead.

But instead of crying, I'm trying to find, how Universe works - not how it can be computed. This is quite different job. But my point is, without understanding, how Universe is working at the nonformal level, every formal model is just ad-hoced regressing of reality, simply a guessing of result.
Alexa
2.3 / 5 (6) Sep 02, 2009
Logical models can have quite different predicative and falsification power, then the formal models. For example, by order of Venus phases the geocentric model can be disproved easily, whereas numerical models are useless, because they give the same results both for geocentric, both for heliocentric model, being fitted into observations. The very same problem occurs in gravitational waves detection: formal models cannot explain so easily, why gravitational waves cannot be observed, because of lost of information during derivation of relativity from Aether model.
Velanarris
3 / 5 (4) Sep 02, 2009
Collisions of particles inside of particle gas cannot be computed, just modeled by computer simulation.
So if it can't be computed, how does a computer model it?

As for Galileo, you are aware that he was the Mathematics chair at the University of Padua, correct? Or that Copernicus had been published on the idea of heliocentricity before Galileo had published any work on the concept?


In 1610 Galileo made his statement on the revolution of Venus around the sun and further to the Earth moving around the sun. This is all published.

Consequently he was the Medici's personal mathematician and engineer at the time.

So now that your example has also been proved false, what excuse will you cling to next to not do the math required?
Ethelred
1.8 / 5 (5) Sep 02, 2009
For example, by order of Venus phases the geocentric model can be disproved easily, whereas numerical models are useless, because they give the same results both for geocentric, both for heliocentric model, being fitted into observations.


The failure of even the very best, not even geocentric but still circular model, was the reason that Kepler finally gave up on the old circular model. Wheels within wheels failed on MATH. The geocentric model failed because it was crap. It said EVERTHING revolved around the Earth. Since the moons of Jupiter didn't then it failed.

The best you can manage to achieve without math is a model that succeeds at not stinking up the place. I am not sure that you even have that. Gravitons to photons is as ad hoc as it gets and there is not a shred of evidence to support it.

Ethelred
Slotin
2.3 / 5 (6) Sep 06, 2009
So if it can't be computed, how does a computer model it?
Particle simulation of fluid doesn't require to solve formal differential equations (Navier-Stokes equations in particular).
.. It said EVERTHING revolved around the Earth...
Nope it didn't, epicycles model of Ptolemy hasn't used a circular path at all and it worked well as it was used thousands years for EXACT! predictions of solar and lunar eclipses and planetary conjunctions.
Alexa
2 / 5 (4) Sep 06, 2009
. Galileo, you are aware that he was the Mathematics chair ..
He was a good mathematicians, neverthelles he disproved geocentric epicycles model just by logical arguments: Venus phases, shades of Lunar craters, etc.. Because if logic isn't working, then the math is BS - not vice versa.
Ethelred
3 / 5 (2) Sep 08, 2009
Nope it didn't, epicycles model of Ptolemy hasn't used a circular path at all and it worked well as it was used thousands years for EXACT!


As is often the case you are wrong and I note that Alexa's post is, if only accidentally, in agreement with me on this. Ptolemy used a cycles and epicycles method which is CIRCLES. And circles didn't work well enough to satisfy the man the replaced circles with elipses, Kepler.

So You and Alizee AND Alexa gave me a 1 for being right and Alizee gave you a 5 for being wrong. Tit for tat.

Ethelred
Ethelred
3 / 5 (2) Sep 08, 2009
Hey that was amazing Alexa. You agreed with me on epicycles AND you gave me one. Or is it that you don't know that epicycles ARE circles?

Tit for tat for you too Alexa. Learn to read before you rate.

Ethelred
Velanarris
3 / 5 (2) Sep 09, 2009
So if it can't be computed, how does a computer model it?
Particle simulation of fluid doesn't require to solve formal differential equations (Navier-Stokes equations in particular).

First, what?

Second, so it can't be computed until you compute it with Newton's second law as applied to fluids.

Talking in circles doesn't help your case. Address the question.
Velanarris
3 / 5 (2) Sep 09, 2009
Or should I say talking in epicycles?

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