Squeezed laser will bring gravitational waves to the light of day

Sep 11, 2011
The new squeezed light laser of GEO600. A highly complex laser system produces light which particularly quiet in the gravitational wave detector. Credit: © Max Planck Institute for Gravitational Physics (Hannover)

A quantum phenomenon allows detectors which sense oscillations of space-time to measure with 50 percent more accuracy.

Measuring at the limits of the laws of nature – this is the challenge which researchers repeatedly take up in their search for . The interferometers they use here measure with such sensitivity that a particular of light – shot noise – limits the measuring accuracy. With the "squeezed light" method scientists from the Max Planck Society and the Leibniz University Hannover likewise use quantum physics in a countermove in order to remove the interfering effect. The new type of laser light improves the measuring accuracy of the gravitational wave detector GEO600 by around 50 percent and thus increases its effective sensitivity. This is the first time this technology has been used outside of a test laboratory anywhere in the world. The results will be published in the specialist journal Nature Physics, online on September 11, 2011.

Some 50 years after the development of the first lasers, the technology of "squeezed light" can be used to generate a completely new quality of laser light. The light from a squeezed laser radiates much more calmly than light from a conventional laser source. "Thanks to the squeezed laser, we were able to increase the measuring sensitivity of GEO600 to 150%," says Hartmut Grote, who heads the detector operation. "The new light source fulfils all requirements as expected." In future, this technology could be used to even double the measuring accuracy. In the search for the almost undetectable gravitational waves, this increase in sensitivity is an important step to their direct detection.

The GEO600 experiment at the QUEST (Center for Quantum Engineering and Space-Time Research) Cluster of Excellence is part of the international LIGO Virgo Collaboration (LVCon) and is putting the researchers from the Max Planck Institute for Gravitational Physics (Sub-Institute Hanover, Albert Einstein Institute/AEI) and from the Institute for Gravitational Physics at the Leibniz University Hannover on the track of gravitational waves. Einstein predicted these oscillations in space-time around a hundred years ago in his General Theory of Relativity. They arise during turbulent cosmic events such as supernova explosions, for example.

Gravitational waves are scarcely noticeable on Earth, however. One reason is that the interaction between matter and space is very weak. Changes to the structure of space-time which occur in our immediate astronomical vicinity as a result of the movements of relatively low-mass objects, such as moons or planets, are way below what is measurable. Turbulent supernova explosions which violently shake space-time occur at a great distance, in contrast. The gravitational waves generated in the process are considerably attenuated when they reach Earth. The relative measuring path in a gravitational wave detector would change by only around a thousandth of a proton diameter if a supernova occurred within our Milky Way. With GEO600, the scientists are meanwhile able to measure such differences in length.

ANU researchers carrying out a related gravity wave experiment

Laser light with constant intensity

In order to be able to make such accurate measurements, the physicists must rely on metrology techniques that are as free from interferences as possible. One of the effects which has caused interference so far is the so-called shot noise. Their quantum nature means the photons rain down at irregular intervals onto the photodiode in the detector. This is evident in the signal as fluctuating background brightness. An oscillation of space-time which causes a similarly weak change in the brightness like the shot noise, can thus only be recognised with difficulty.

Roman Schnabel and his research group in Hannover have now developed a special light source with which the disturbing shot noise can be curbed. When integrated into GEO600, the squeezed light laser assists the gravitational wave detector to a new measuring sensitivity. This makes the GEO600 the first detector whose signal beam is smoothed with the new type of laser light.

The Heisenberg uncertainty principle states that the intensity and colour of a laser beam cannot simultaneously be defined with arbitrary accuracy. For example, the more exact the intensity (to be more precise: the amplitude) is specified, the more uncertain the colour becomes (to be more precise: the phase). The quantum physicists utilise this effect to minimise the shot noise in the GEO600 experiment. After all, the shot noise is actually nothing more than an uncertainty of the laser intensity. They improve the laser light so that its intensity is very accurately defined, i.e. exhibits almost no fluctuations. The experts also call this process "squeezing". In this experiment, it is of no consequence that the light colour becomes more imprecise, i.e. slightly more "colourful", since this parameter is not included in the measurement data.

"We now feed the squeezed light into the interferometer, in addition to our normal ," explains Schnabel. "If the two light fields then superimpose, the resulting laser beam has a much more uniform intensity, compared to the original signal beam. "We thus smooth out the irregularities caused by quantum physical effects in the detector signal," Schnabel continues.

The squeezed light laser has been undergoing a longer test phase since April last year at GEO600 and is now being used in the search for gravitational waves. The application of squeezed technology has thus passed the acid test. The American colleagues within the LVC plan to soon test a squeezed on the LIGO detectors.

Explore further: MRI for a quantum simulation

More information: Paper online: http://dx.doi.org/10.1038/NPHYS2083

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dav_i
4.2 / 5 (6) Sep 11, 2011
Gravitational waves are scarcely noticeable on Earth...

or anywhere else for that matter - gravitational waves have not been detected.

I wonder how much this method weighs/sizes compared to normal lasers. I.e. would it be possible to adapt for LISA?

Also... the phrase "squeezed light" reminded me of Brasseye's "heavy electricity". :)
Callippo
2.5 / 5 (8) Sep 11, 2011
Gravitational waves are actually well known CMBR noise. As Eddington pointed out already before many years, gravitational waves do not have a unique speed of propagation. The speed of the alleged waves is coordinate dependent. A different set of coordinates yields a different speed of propagation and such waves would propagate like the noise.

Relativists use a simplified form of Einstein field equations to calculate various properties of his gravitational field, including Einstein gravitational waves, which are based on the Einstein's pseudo-tensor. This simplified form is called the linearised field equations. They do this because Einstein's field equations are highly non-linear (implicit actually) and impossible to solve analytically. So they use the linearized form, simply assuming that they can do so. However Hermann Weyl proved in 1944 already, that linearization of the field equations implies the existence of a Einstein's pseudo-tensor that doesn't otherwise exist.
vacuum-mechanics
1 / 5 (1) Sep 11, 2011
How gravity wave could propagate via the non physical medium of space-time?
Callippo
1.8 / 5 (5) Sep 11, 2011
How gravity wave could propagate via the non physical medium of space-time?

The same question can be put about light waves..;-)

But at the case of gravitational waves the conceptual problem of their definition rather is, the gravitational wave is formed with curvature of space-time and the position of artifacts in general relativity is defined only with respect to curvature of space-time (the flat space-time poses no reference frame for definition of location). In such way the position of gravitational wave is defined it's own position, which leads into circular reasoning of its existence.
Seeker2
2 / 5 (4) Sep 11, 2011
How gravity wave could propagate via the non physical medium of space-time?

Non-physical? Maybe it's just invisible. Sort of like clean air.
Isaacsname
not rated yet Sep 11, 2011
Just out of curiousity, does radiation pressure contribute to an object's invariant mass ?
Seeker2
1 / 5 (6) Sep 11, 2011
Sort of like clean air.


Actually space-time has viscosity, like air. For example the earth burns about 200 watts in its orbit every year. This degrades the orbit so the earth is falling into the sun. Eventually everything is going to collapse into one giant ball before the next big-bang.
Seeker2
1 / 5 (3) Sep 11, 2011
Just out of curiousity, does radiation pressure contribute to an object's invariant mass ?

Put it in a microwave and I guess it heats it up.
ED__269_
1 / 5 (2) Sep 11, 2011
"The Heisenberg uncertainty principle states that the intensity and colour of a laser beam cannot simultaneously be defined with arbitrary accuracy."

If the parameters are tested for one, data accumulated over time; then the parameters for another tested, comparative data accumulated over time; then perhaps a method of simultaneous detection, might actuate? how uncertain can it remain in the face of continuous testing?

a color test;

For instance DM's property of high energy particle physics? -- a potential shift? a distorted spacetime moment? phase waves to what precise comparative/expectation?

--. .-. --- ..- -. -.. ... ??????
if we do not give space the time, can you give it to zero space?

-.-- . ... ?????
graphically - can such intensity translate to real space?

at what color?
Sonhouse
1 / 5 (2) Sep 11, 2011
"The Heisenberg uncertainty principle states that the intensity and colour of a laser beam cannot simultaneously be defined with arbitrary accuracy."

If the parameters are tested for one, data accumulated over time; then the parameters for another tested, comparative data accumulated over time; then perhaps a method of simultaneous detection, might actuate? how uncertain can it remain in the face of continuous testing?

a color test;

For instance DM's property of high energy particle physics? -- a potential shift? a distorted spacetime moment? phase waves to what precise comparative/expectation?

--. .-. --- ..- -. -.. ... ??????
if we do not give space the time, can you give it to zero space?

-.-- . ... ?????
graphically - can such intensity translate to real space?

at what color?


Groundless? except you left off the last ...
technodiss
3 / 5 (2) Sep 11, 2011
How gravity wave could propagate via the non physical medium of space-time?

Non-physical? Maybe it's just invisible. Sort of like clean air.

clean air? that's something a lot of younger people have never experienced. i know its been a while for me.
Sonhouse
1 / 5 (1) Sep 11, 2011
grounds les Doesn't make sense.
Seeker2
2.3 / 5 (3) Sep 11, 2011
...clean air? that's something a lot of younger people have never experienced. i know its been a while for me.

Yea I'm pretty old too. Think of it as an abstract concept.
ED__269_
not rated yet Sep 11, 2011
@ groundless, then can a Gwave propogate in non spacetime?

-. --- ?????

for an isolated single point, how do you graphically represent that as a closed system without zero?
Seeker2
1 / 5 (8) Sep 11, 2011
... Eventually everything is going to collapse into one giant ball before the next big-bang.

The last thing to get sucked up into a black hole after they eat up all matter and space-time in the universe is the anti-matter lurking in the far reaches of the universe. Best hope you're in heaven by then because that's when it's deja vu all over again.
Callippo
1.6 / 5 (7) Sep 12, 2011
I know, you finite people are fixated to the concept of the beginning and end, but the Universe is not fixated to anything. The Big Bang wasn't and the black holes will never "eat all matter".
Seeker2
1 / 5 (2) Sep 12, 2011
...The Big Bang wasn't

Right. The big bang is just part of life, one of the phases nature goes through, not the beginning. There is/was no beginning. There is no end. It's just over and over again. At least as long as 2 2=4. Infinite. Deja vu all over again.
Seeker2
2.3 / 5 (3) Sep 12, 2011
...2 2=4

Flood control? Quick. Let's try that again. 2 plus 2 equals 4.
antialias_physorg
5 / 5 (3) Sep 12, 2011
And how does 2 plus 2 equals for make any argument for Infinity?

It only means that both may seem equally clear to you. But in this case you are right on one and wrong on the other.

Stuff may be big. But 'infinite' isn't on the menu. neither for space, time or whatever else you can measure. (Because for there to be something to measure you need to discriminate betwen things and that already means a finite measure/value set)
Seeker2
1 / 5 (1) Sep 12, 2011
... a finite measure/value set)

Try that on measuring pi.
Isaacsname
not rated yet Sep 12, 2011
Just out of curiousity, does radiation pressure contribute to an object's invariant mass ?

Put it in a microwave and I guess it heats it up.

..thanks...nevermind, I looked it up, the answer is yes.

*pats self on head*

http://en.wikiped...pressure

http://en.wikiped...reaction

Fascinating
antialias_physorg
4 / 5 (4) Sep 12, 2011
Try that on measuring pi.

My point exactly: PI is an abstract. There is no perfect circle anywhere in the universe (since that would require infinite matter and/or something that is not quantized or falls under an uncertainty principle on any level. )

You cannot 'measure' PI to the last digit. Any real application that we would call a circle has a finite value for PI. Only in the abstract/mathematical sense of circles does PI have a truly infinite number of digits.
Seeker2
1.5 / 5 (4) Sep 12, 2011
...You cannot 'measure' PI to the last digit

Right except there is no last digit. However I feel certain that the universe has been around for a time equal to the total number of digits.
Seeker2
1 / 5 (2) Sep 12, 2011
...the universe has been around for a time equal to the total number of digits

Right. And remember the number of digits goes up by one every year.
antialias_physorg
5 / 5 (4) Sep 12, 2011
Right except there is no last digit.

That's why I said PI was an abstract.

Take any real circular entity and measure PI for it. You will find that it is impossible because at the atomic level you run into granularity (and a measure of PI demands a continuously differntiable curve). Further down you run into Heisenberg Uncertainty where you can't even measure exact locations/lengths anymore.

So PI - while beeing an exceedingly helpful abstract notion - does not have a perfect representation in the real word.

And remember the number of digits goes up by one every year.

And that number, too, is finite (and always will remain so).
Seeker2
1 / 5 (1) Sep 12, 2011
...And that number, too, is finite (and always will remain so).

So what would that number be?
antialias_physorg
4 / 5 (4) Sep 12, 2011
So what would that number be?

Since time is a measurement of entropic increase we will (according to current cosmological models) get to a point where the universe reaches maximum entropy (heat death of the universe - the time when the final black hole will have evaporated).

At that point all we will have left are vacuum fluctuations - so the total entropy state will fluctuate around this final value. A measure of time is then impossible since the arrow of time becomes indefinite (i.e. looking at 'snapshots' of two states of the universe it is then impossible to say which one is before the other one)

Depending on which source you go to we get the rather large spread of between 10 to the 77 power and 10 to the 126 power years (which is an enormous span - but by no means infinite).
Seeker2
2 / 5 (4) Sep 12, 2011
...the time when the final black hole will have evaporated).

Yes, assuming black holes will be around that long. However recent observations of the CMB reveal circular patterns suggesting to Roger Penrose a collapse of of the universe before the big bang. Sounds better than heat death anyway.

antialias_physorg
4 / 5 (4) Sep 12, 2011
Then we really need a new force, because recollapse doesn't work with the accelerated inflation we are witnessing.

To get a recollapse we need an ultra long range force (i.e. one that is even longer range than gravity) which is somehow being suppressed until now and can overcome this accelerated phase. Such a force would need to go into effect before the Big Rip and also be instantaneous (i.e. transmitted at faster than light speeds). Those are some pretty big problems. We have as yet no indication that such a force exists.

As for the circular patterns in the CMB - that one is still on shaky ground as the fluctuations in the CMB are so incredibly minute. (and even if: it could have all kinds of other explanations besides a big bounce - we'll have to wait until the new sky survey finishes to get a final verdict on that one)
Seeker2
1 / 5 (4) Sep 12, 2011
...recollapse doesn't work with the accelerated inflation we are witnessing.

Seems to be a natural effect of an expanding volume. I have showed at
https://skydrive....D%215333
that as the increase in radius decreases by 10 percent the increase in volume increases in the early stages of expansion (sheet 1), indicating we are in the early stages of expansion.
vacuum-mechanics
not rated yet Sep 12, 2011
How gravity wave could propagate via the non physical medium of space-time?

The same question can be put about light waves..;-)

But at the case of gravitational waves the conceptual problem of their definition rather is, the gravitational wave is formed with curvature of space-time and the position of artifacts in general relativity is defined only with respect to curvature of space-time (the flat space-time poses no reference frame for definition of location). In such way the position of gravitational wave is defined it's own position, which leads into circular reasoning of its existence.

How non physical space could be curved?
Seeker2
1 / 5 (1) Sep 12, 2011
...How non physical space could be curved?

Maybe it's physical.
frajo
1 / 5 (1) Sep 13, 2011
But 'infinite' isn't on the menu. neither for space, time or whatever else you can measure.
For space, we'd first have to define "infinity" in a higher-dimensional, possibly convoluted object.

For time, we'd have to discuss its meaning first. Equating time with entropy is just the most fashionable of several possible philosophical interpretations of our perception of a physical phenomenon. Another one, better fit to cope with observations than the Christian biased idea of time's alpha and omega, is indeed the notion of a time without beginning and ending.
The absence of beginning end ending of time is simpler in the sense of Occam's razor and thus preferable. Calling a time without beginning and ending "infinite" is quite reasonable.
antialias_physorg
not rated yet Sep 13, 2011
Another one, better fit to cope with observations than the Christian biased idea of time's alpha and omega, is indeed the notion of a time without beginning and ending.

That's just a definition without any rationale to back it up - thus Occam's Razor doesn't apply.

Seems to be a natural effect of an expanding volume. I have showed at

I think you ned to check your numbers. you're not using an increasing inflation rate (which is what we measure) but a decreaseing inflation rate. And even in your faulty model there is only a decrease in the expansion RATE - but never a recollapse.
frajo
1 / 5 (1) Sep 13, 2011
PI is an abstract.
No more abstract than any other transcendental number.
There is no perfect circle anywhere in the universe (since that would require infinite matter and/or something that is not quantized or falls under an uncertainty principle on any level.)
Any physical object called a "circle" is only an abstraction of a mathematical circle which is - by definition - perfect.
You cannot 'measure' PI to the last digit.
There's no need to measure PI as it's exact by definition. But its (approximizing) representation by a finite number of (decimal or other) digits can be calculated.
Any real application that we would call a circle has a finite value for PI.
PI always has a finite value.
Only in the abstract/mathematical sense of circles does PI have a truly infinite number of digits.
Representations are not qualities inherent to numbers. PI would be represented best by its Greek symbol, as in its defining equation: cos(PI/2) = 0.
frajo
1 / 5 (1) Sep 13, 2011
So PI - while beeing an exceedingly helpful abstract notion - does not have a perfect representation in the real world.
It does. Usually the perfect representation is the small Greek letter for PI. In case this letter cannnot be used (as in this forum and most programming languages) the preferable perfect representation are the two letters PI.

Annotation:
While most people view the number PI from a (historically primed) geometrical PoV, the mathematically more important PoV is the analytical one via the Taylor series of the cosine with argument PI/2.
antialias_physorg
not rated yet Sep 13, 2011
No more abstract than any other transcendental number.

So? The argument goes for all transcendental numbers. None of these have a perfect representation in reality. They only exist as 'absolutes' in the abstract context of mathematics.

Whether you represent them in a symbol or as a string of numbers doesn't matter.

The point is that infinity is an abstract notion and not a property of reality. Just like green purple or dark light (or 'god' if you will) are abstract notions but occur nowhere in reality. Putting words to a concept doesn't make it real.
frajo
1 / 5 (1) Sep 13, 2011
Another one, better fit to cope with observations than the Christian biased idea of time's alpha and omega, is indeed the notion of a time without beginning and ending.

That's just a definition without any rationale to back it up - thus Occam's Razor doesn't apply.
It's certainly not a definition of time; it's a description. And its rationale is the effort to get rid of culturally induced bias.
Occam's razor is applicable wherever two different scientific explanations work equally well in describing the same physical phenomenon.
All present cosmological models based on the concept of a mystical "boundary point zero" for the universe fall short of providing a non-mystical rationale for this concept.
Seeker2
1 / 5 (1) Sep 13, 2011
...you're not using an increasing inflation rate

Check column E sheet 1.
Seeker2
1 / 5 (1) Sep 13, 2011
... never a recollapse.

That's not the nature of an expanding volume which is what I'm talking about. Once the expansion slows down there are various collapse scenarios.
Seeker2
1 / 5 (1) Sep 13, 2011
... infinity is an abstract notion and not a property of reality

Maybe for space but not time.
Seeker2
1 / 5 (1) Sep 13, 2011
...There is no perfect circle anywhere in the universe

Actually if there was one and you had it in your lab you never could prove it was perfect.
Seeker2
1 / 5 (1) Sep 13, 2011
...infinity is an abstract notion and not a property of reality

You may be sitting right in the midst of it and never now it. Watch out for conventional wisdom. Yes this universe is finite in space but there's lots more room for other universes out there. There are no walls or borders that I'm aware of.
Seeker2
1 / 5 (1) Sep 13, 2011
...Just like green purple or dark light (or 'god' if you will) are abstract notions but occur nowhere in reality.

Dark light? Both at the same time?

I thought green or purple could be described by some wavelengh of light. Not really that abstract.

I wonder if god were around would he have an id card? How would you know? Maybe you could ask him for a business card. Conventional wisdom would seem to be never count out the god option.
antialias_physorg
not rated yet Sep 14, 2011
Maybe for space but not time.

Since we're dealing, at least since Einstein, with spacetime I don't see how you can argue for a finite space and a separately infinite time. The two aren't independent.
Seeker2
1 / 5 (1) Sep 14, 2011
,,,I don't see how you can argue for a finite space

I meant finite space only for the observable universe. Other universes would have to be separated from observation or causality by no connecting spacetime to communicate light or gravity.
Seeker2
1 / 5 (1) Sep 15, 2011
...an ultra long range force (i.e. one that is even longer range than gravity

That would be pretty long, as least per Newton: the force is greater than zero as long as the distance between two masses is finite.
antialias_physorg
not rated yet Sep 16, 2011
Igf you agree to a start of spacetime at the Big Bang then any event has a finite spacetime coordinate.
If you go for cyclic universes then you still have to find a point at which the cycling started.
If you do not want to define such a point then you have just refused causality (which makes any argument about inifnities moot because without that would make any type of sequencing irrelevant)
Seeker2
1 / 5 (1) Sep 16, 2011
... you still have to find a point at which the cycling started.

Easy. It started as soon as 2 plus 2 equals 4.
frajo
1 / 5 (1) Sep 17, 2011
I meant finite space only for the observable universe. Other universes would have to be separated from observation or causality by no connecting spacetime to communicate light or gravity.
"Other universes" of that kind are mere speculation as any theory proposing them will be unfalsifiable and therefore, by definition, unscientific.
frajo
1 / 5 (1) Sep 17, 2011
If you go for cyclic universes then you still have to find a point at which the cycling started.
The assumption of a starting point implies - by mathematical definition of borders - an outside and an inside relative to that point. Which is equivalent to postulating either a "nothing" or "something" on the other side of that border point. While "something" would mean a physical "outer universe" the concept of "nothing" is metaphysical only.
If you do not want to define such a point then you have just refused causality
A universe without starting point is not violating causality as it has no cause and needs no cause. It just is existing. The assumption of it's non-existence is metaphysical only.
(which makes any argument about infinities moot because without that would make any type of sequencing irrelevant)
I don't understand this. But as we can measure time intervals at most from one collision of branes (aka BigBang) to the next one, it wouldn't matter.
Seeker2
3 / 5 (2) Sep 17, 2011
...unfalsifiable and therefore, by definition, unscientific.

Interesting. So falsifiable would mean scientific. Something to think about.
Seeker2
1 / 5 (1) Sep 17, 2011
...It just is existing

Reminds me of one of the creeds - "begotten, not made, being of one substance with the father", or something like that.
Seeker2
1 / 5 (1) Sep 17, 2011
..."Other universes" of that kind are mere speculation

"only universe" would seem a bit speculative also. Maybe also a bit presumptuous.
frajo
1 / 5 (1) Sep 18, 2011
..."Other universes" of that kind are mere speculation

"only universe" would seem a bit speculative also. Maybe also a bit presumptuous.

By definition, the universe comprises the totality of directly and indirectly measurable physical objects.
Scientists are humble and modest by limiting the scope of their work to objects that are - at least in principle - accessible by observation.
Anything beyond that scope, in particular objects that - in principle - cannot be observed is considered not to be accessible to physical reasoning.
It would be unmodest and presumptuous to lend the same weight of meaning and certainty to principally unaccessible objects and their unfalsifiable embedding theories as to physical objects that are modelled by falsifiable, i.e. scientific, theories.
Abandoning of speculation increases the certainty of knowledge. That's what science is about.
antialias_physorg
not rated yet Sep 18, 2011
So falsifiable would mean scientific.

Maybe you should read the definition of scientific theory before trying to make statements about it?
From the wikipedia link on "scientific theory":

"The defining characteristic of a scientific theory is that it makes falsifiable or testable predictions."

http://en.wikiped...criteria
Seeker2
1 / 5 (1) Sep 18, 2011
...Abandoning of speculation increases the certainty of knowledge. That's what science is about.

..."The defining characteristic of a scientific theory is that it makes falsifiable or testable predictions."

You'd think you could work in a little common sense in there somewhere.

hush1
5 / 5 (1) Sep 22, 2011
Attempt at common sense:
Science vs. Metaphysical.

Predictions come and go.
Science records this.
antialias_physorg
5 / 5 (1) Sep 22, 2011
You'd think you could work in a little common sense in there somewhere.

Where would have common sense gotten us with quantum physics? Quantum physics is real, but 'common sense' would have rejected the notion that stuff can be everywhere at once (and did for a long time).

Similarly relativity: Common sense would tell us the path of massive objects is bent - but relativity shows that it's straight - only space is warped.

Science doesn't need to conform to what you think common sense should be. It is confined to what works.
rawa1
1 / 5 (1) Sep 22, 2011
Science doesn't need to conform to what you think common sense should be. It is confined to what works.
It's confined to theories instead of facts. The gravitational waves doesn't work, the cold fusion works contrary to theories. In both cases the science follows the opinion of theories, not experimental facts.
rawa1
1 / 5 (1) Sep 22, 2011
Despite wasting millions of taxpayer dollars searching for gravity waves predicted by the theory, none has ever been found.

http://conservape...lativity

My question rather is, which evidence should happen for physicists to stop invest billions of dollars into search of gravitational waves.

http://physicswor...1a19.pdf

http://physicswor...ws/46027

BTW The sqeezed light is used from 2008 year in GW detectors. It's not new feature, as this propaganda implies - but no GW were found yet with it or without it

http://physicswor...ws/33755
Bryan_Sanctuary
1 / 5 (1) Sep 24, 2011
A problem with QM is it is a theory of measurement restricted by Heisenberg's relations. Looking for gravity waves with photons might just destroy what we are looking for. What we need is an indirect way of observing gravity waves such that the effects are manifested in some other macroscopic (i.e measurable) way. Do no have any idea how.
antialias_physorg
not rated yet Sep 24, 2011
ooking for gravity waves with photons might just destroy what we are looking for. What we need is an indirect way of observing gravity waves such that the effects are manifested in some other macroscopic (i.e measurable) way.


You mean like observations of the Hulse-Taylor binary system?
http://en.wikiped...r_binary
Seeker2
1 / 5 (1) Sep 26, 2011
...Where would have common sense gotten us with quantum physics?

Of course. I should have included imagination, creativity, and initiative.