LIGO Gravitational Wave Observatory

[geonerd]

The people who put together this propaganda video must feel pretty silly by now. (It's 2012 and not one GW signal has been detected.)

Now much longer will LIGO be funded?

[tyronejonez01]

WHEN YOU BEND ANY ELECTROMAGNETIC RADIATION YOU LOWER THE FREQ. SO WHAT DO THINK HAPPENS WHEN LIGHT GOES BY A STAR? TIME IS A SUBSET OF GRAVITY MAYBE GRAVITY COMES IN 2 POLARITIES IF THERE IN NO GRAVITY, IS NO TIME? I BELIEVE THE SEARCH FOR A GRAVITY WAVE WILL FAIL

[raybanfandom]

@tyronejonez01

All caps does not give you an extra inch of authority.

[chuobio]

2:06 - How did they make sure it was a gravity wave?

[bygota]

brilliant !!!

[huni54]

funny because they have made the big bang as a big noisy explosion:D when in fact it was a silent one.. without any atmosphere there is no soind so the big bang couldnt have said: BOOOM!!

[josyula547]

i couldn't stop my tears...intimidating idea!!

[videogamegirlsings]

i went yesterday it was a little fun in livingston parish

[CACBCCCU]

To recap a bit, the theory seems to be that light is unresponsive to a gravity wave but not LIGO length, or maybe it should be that LIGO length is unresponsive but not light, in any case they do not respond equally. SR's lightspeed constancy seems to get violated any way. Althernatively saying that material length scales together with space and light would be to say LIGO won't work, but it conserves SR, all without touching the essence of GR.

[CACBCCCU]

An alternative for justifying the perspective I mentioned is to think of the visual bunching of on-sheet concentric circles, matching blue/red shifting, as being an effect of light and space both compressing/expanding together as light approaches/escapes a mass. If material lengths do not follow with space compressing/expanding, one can't put LIGO and its lightwaves on the same elastic sheet and gravity waves won't be nulled. Seems to be the theory here.

[CACBCCCU]

Guess I'm stuck on the elastic-sheet GR idea. Seems equally valid to describe gravity as a thing stretching the sheet instead of one curving it. To me the right perspective for the 2D sheet is looking at it from above, straight down, so the stretch makes concentric circles bunch up close to a mass, matching red/blue shift going to/from it, but it implies light doesn't stretch going in, it unstretches, or else space stretches but not light, contradicting a light/space metric.

[CACBCCCU]

Seems a gravity wave moving at lightspeed is supposed to deform the interferometer's light speed relative to the interferometer structure, as if both won't stay on the same rubber sheet. If only the apparatus is on the sheet, not the light, then it's just like a seismometer. I'm not really sure exactly how a deformation moving at light speed is supposed to deform apparatus light speed, however it seems like it's basically saying SR and gravity waves don't mix.

[CACBCCCU]

Suppose I take a schematic diagram of the interferometer, including the wavy lines representing the lightwaves, and print it on a sheet of rubber, and then I stretch the sheet, I'm supposed to expect the lightwaves jump off the sheet. Eh.

Instead, suppose light is more responsive to the stretching than is the interferometer structure, blame momentum. Now, a gravity wave passes at light-speed, and somehow this changes the time it takes for light to go half-way up an arm? Double eh.

[CACBCCCU]

So, the gravity wave is supposed to affect the interferometer apparatus but somehow not supposed to affect the light that's inside of it in the same way. Might as well call it a seismometer.

[sirfreakman]

Maybe it's explained in the video, but I don't get how gravity waves can distort the OPD (Optical Path Distance of the Mirrors).

[drcaos]

@sirfreakman Maybe the wave it´s just moving the mirrors my dear friend.

[o0oD4n1so0o]

6:44-6:46 "revolutionary instruments" How can a light beam (Laser) and few mirrors be called revolutionary instruments?

[FFOTUC]

Gee why does this look like the Michelson–Morley experiment? Instead of looking for the luminiferous aether they are looking for g-waves. I guess something old is new again.

[r0ck3tsm0k3]

@FFOTUC It is similar, but exceptionally more sensitive.

[tyrantemperor77]

you couldnt be more wrong nfexp, recently they put Einsteins relative theory equations through a "super" computer and according to scientist he was on to something, but there was more to the equation. so he was partially right, in the sense that there's more to it.

[nfexp]

Einstein was wrong...there is no such a think like space-time bending. There is no one single proof of relativity that cannot be explained with other effects....

[seanmPWH]

@nfexp How about giving an example.

[nfexp]

@seanmPWH Sure...They observed that a neutron will fall in steps rather than having a linear accelerated falling as predicted by GR. Here you can find the original publication, i guess from around 2002:

ww.ill.eu

[sidewaysfcs0718]

@nfexp

ever heard of the GPS?

[BlackBarMusic]

Why would a gravitational wave not affect the laser beam?

[anarchopinko]

@BlackBarMusic It does affect the beam. The path through spacetime that the beam travels on is perturbed less than the path that the masses take through space time.

[MrRodneykawecki]

Gravity and or ghravity waves havebnyet been detected. In space matter is warping dark matter. On earth..gravity is the energy action between two objects...one being the planet. SUPERTELLIC UNIVERSE...

[ytmoog]

Yet to be detected directly.

They have been detected indirectly. Systems with two pulsars in a close orbit have been detected losing energy exactly as predicted by gravitational waves.

The next step is to measure them directly, hopefully soon.

[sean6006]

Actually, I think that gravity waves (or the 'graviton') travel at at the speed of light, so to say that if the sun were to suddenly vanish it would take ~8 min for the earth to go off into space on a tangent. Also, can't we prove that gravity is a wave by observing gravitational interference? or by cancelling gravitational waves? Or shouldn't we be able to observe a doppler effect from distant galaxies? There are so many things to consider: What would be the frequency? My head is exploding...

[ehswan]

What is most essential at this time is to determine the velocity of the propagation of gravity. Finite or infinite?  That is the question. If it is finite we are doomed to live in our little room, if infinite then we can visit our neighbors, and they can visit us.

[anarchopinko]

Gravity propegates at the speed of light according to Einstein's general relativity.

[ehswan]

A little thought experiment here. Suppose that gravity propagates at INFINITE velocity! How could an infinitesimal period of time be measured? Answer: no way! You all, by your absurd presumption, in my opinion, are DOOMED to FAIL Ha Ha .

[anarchopinko]

@ ehswan. Grav waves travel at the speed of light so...you fail Ha Ha.

[etiennealive]

In the Netherlands they are constructing an underground placed coper bol with a large diameter to detect gravitational waves. What do you think of this concept.? (they expect the bol to vibrate).

[jingling30]

I think they should be putting more efforts in colliders to confirm supersymmetry to further develop string theory.

[anarchopinko]

String theory is an esoteric theory that probably will not be helped by colliders. We know that gravitational radiation exists because of the Hulse Taylor binary pulsar measurements. Gravitational wave astronomy will give us new information about the universe.

[ewmegoolies]

So, now everybody that has an opinion and doesn't publish a paper is a crackpot? Is that code word for squander a bunch of your own time before you take away our funding? What have you published to support this "proof of principle" as valid or validated?

[ewmegoolies]

Its running more than 5 years and hasn't detected anything. Because light does not travel any faster through contracted space as it would through expanded space (or our frame). If your meter stick is length contracted due to acceleration, light would not reach the end of the stick more quickly... Right?!

Putting one of these in outer space would likely get the same result. Thus, it would be a waste of resources.

Ligo and similar experiments need to be retired for now...

[wganderson12]

Uhh ... the current version of LIGO is a proof of principle, and it was not expected to detect gravitational waves. If the next generation of LIGO doesn't detect anything, that would be surprising. As for your argument that light does not travel any faster through contracted space, that is true in one frame from which you can analyze the system. In that frame, however, the frequency of the light changes. I suggest you do the math before you decide whether there is a measurable effect or not.

[ewmegoolies]

Unless, LIGO predicts we live in a holographic universe, the only math needed for this project is an accountant to figure how much money has been wasted. I suggest somebody do the math quickly.

[wganderson]

So, publish your paper on the fundamental flaw of using a Fabry-Perot interferometer to measure gravitational waves is fundamentally flawed in a reputable peer-reviewed physics journal and show us all to be wrong. I guarantee I'll read it. Or are you just another crackpot who thinks that having an opinion is the same as doing physics?

[anarchopinko]

Light moves on the null geodesic while masses move on massive geodesics. The amount that Light's path through spacetime is perturbed by a gravitational wave is different from masses.

[BrainChild666]

Telsa discovered these waves back in 1898. Standing Columar Waves,Terrestrial Stationary Waves,Tesla Waves,Phi Waves,Scalar Waves are all the same thing with different name.

Tom Beardon and Dan Winter are the Telsas' and Heavisides of our time.

These Scientist in this video use RENORMALIZATION on all there mathmatical hypothesis.

[anarchopinko]

Branchild666 - Tesla did not discover these waves. These waves are perturbations in spacetime. Tesla had nothing to do with that.

[BrainChild666]

Yik es I went to your channel. Bill Nye?

Tesla was creating Scalar Waves at 50 times the speed of light. Oliver Heaviside had a grand unification theory in 1889. Your favorited indicate the level of your UNDERstanding of Science. Scientist everywhere credit Tesla as the first to discover this wave that is why they are referred to as TESLA WAVES. Might want to do some research before eating your own foot.

BrainChild Out..........

[anarchopinko]

Actually, BrainChild I am a theoretical physicist who has worked on the LIGO project in the past - so my knowledge of physics is good enough that I get paid for it. Tesla waves are Electromagnetic waves - not ripples in space time. These are two totally different things. Gravitational radiation is not electromagnetic radiation.

[anarchopinko]

Tesla waves (or scalar waves) are specifically electromagnetic longitudinal waves - meaning that the 2 oscillating parts are antiparallel to each other and have no net direction. They are not considered part of mainstream physics at all and are absolutely not the same as gravitational waves.

[anarchopinko]

Scientists everywhere do not credit discovering gravitational waves with Tesla - because he didn't. Einstein came up with the theory that predicted them, Hulse and Taylor won the nobel prize for indirectly measuring them in a binary pulsar system, and Weber tried to find them without success. Tesla had nothing to do with it at all.

[BrainChild666]

Electromagnetic waves are limited by a vector. Scalar waves are superluminal not bound by the vector. all those scientist that GET PAID to do experiments are given grants and goals that they must operate under. Tom Bearden explains it best in this short vid. Tesla had everything to do with it.

/watch?v=wypYFe3JXdE

Could you post some videos of you working in your lab with your paid scientist friends. Since you dont have any videos of your own. That equal no credibility.

BrainChild Out...

[anarchopinko]

Well since I am a theorist I do not work in a lab. Also, I prefer anonymity - the interwebs are full of crazies. Gravitational waves are not superluminal - they move at the speed of light. They are ripples in the fabric of spacetime, or, if you prefer, they are linearized perturbations of the metric.

[anarchopinko]

The video you posted has to do with electromagnetic phenomenon - nowhere does it mention gravitational waves or Tesla. Gravitational waves are predicted phenomenon using Einstein's General Theory of Relativity. They were never detected by Tesla. You are confusing yourself to the point of absurdity.

[anarchopinko]

Scalar waves are non-conventional pseudoscientific versions of electromagnetic waves. They are not accepted by mainstream science and still have NOTHING TO DO WITH GRAVITATIONAL WAVES AT ALL. Please do research. Just type Tesla and gravitational waves into google search and you will find that you get zero connection between the two.

[BrainChild666]

Ha you have exposed your self.PROGRAM

go watch some TV......hahahahahhaha

Drink your Flouridated Water and eat your

Genetically Modified Foods calling people on your MICROWAVE drivin cell phone taking Vaccines filled with HIV and SD40 cancer virus will inhalling nanoparticles sprayed on to us via CHEMtrails which inable that HAARP weapon to manipulate the WEATHER and your Brain...Causing you to think MAINSTREAM is real and TV is the TRUTH. GOOGLE is NSA.

BrainChild Out............

[anarchopinko]

Exposed myself? I am not sure what these psychotic ramblings mean other than that you are a crack pot. If you have science that is outside mainstream it is quite easy to make it mainstream if it is legit - just publish your results. People like Bearden are crackpots because their work is so poor and inconsistent that it doesn't get past peer review - Bearden will spin this and claim conspiracy in order to victimize himself and keep from admitting that he is a crackpot.

[anarchopinko]

Regardless of all your crazy talk - it doesn't change the fact that you are totally confused about Tesla's scalar waves (and Bearden scalar field theory) and gravitational waves. These are not the same thing. The former has to do with electromagnetism and the latter has to do with spacetime. You inability to provide and references for your silly claims and your latest attempt to move the goal posts shows that you are to proud to admit that you are wrong - these are the signs of a crack pot.

[BrainChild666]

I thought you would watch the whole series its only 8 parts. I can understand your position on anonymity online.

I think that you are swamped with Scientific Dogma like those Global Warming Fauds not willing to stray to far from your comfort zone. Bearden Talks about Tesla, Gravitational Waves,Scalar Waves and there Superluminal capabilities through this entire series. maybe you want to start here:

/watch?v=P4FGkU841UI

BrainChild Out..

[VideoMagician77]

So What! If you prove there are gravity waves then scientist can track the earliest gravity wave from within 1 trillionith of a second after the big bang therefore going that early in time we can discover the source,creation, and meaning of life itself this should excite you like it excites me

[VirtRampage]

ok so you prove that there are gravitational waves, so what?

[Thymonico]

Science prevails! :D

That, and we could possibly use these waves as a tool to communicate and send information. We'd want to use GWs because they won't get distorted by anything else.

[ashoka81abm]

I am a naive..But let me ask ..

Is LIGO able to filter the disturbances from seismic waves?.Coz the shock waves coming from an earth quake can also cause some change in distance(very very fractional) between the two mirrors???

[akranis]

That is why there are two of them. Even if the quake could reach both of them, they'd be out of sync with each others.

They're only looking for data that looks exactly the same at both labs.

[ashoka81abm]

Thanks for the reply !!!

[ItCameFromTheSkyBeLo]

Yes, they have to filter stuff happening all around the world, as its very sensative. It picks up sounds as quiet as peopels alarm clocks every morning, they have to filter out everything. The most effective LIGO would be a space observatory.

[johnsidicouplay]

I can constantly hear a strange humming during many parts of the day. I have been able to hear this hum for about 3 to 4 years now. I am almost convinced now that this well discribed hum by some others whom can also hear this from different places around the world is in fact the perception of gravitational waves. Freaked me out a little when I first started hearing it.

[pjholl]

You have to remeber that your ears are sensitive to pressure waves in air, not spacetime. Believe me if fiding gravity waves was as simple as listening for them, they would have been found along time ago.

[aiusepsi]

It's much more likely you have tinnitus.

[VirtRampage]

or youre nuts

[omegagod]

lol @ Virt

[bellinivernon]

Exelente ! ;gracias ,desde argentina.

[RtistFrozn]

I'm scared...we're supposed to get one of these tomorrow! O.O''

[faro0485]

Do they work?

I've heard they're doing it wrong.

That is... they're not using an extra dimension.

[Qulopuaa]

man naivism- you dont know whats out there in space/other universa, your god-faith is just plain stupid as a newborn kitten miaoing to the world , here i am, Who would take contact with a canibal (man)

[seopeter22]

all this spacetime stuff seems useless unless we colonize space. otherwise we're stuck on earth and time distortion is irrelevant.

[julien1976julien]

Wow.

[seopeter22]

does that mean if there is such a thing as hyperspeed travel, the carrier is on regular time while the universe around it are at almost complete pause in time?

[Color1377]

humans are freaking amazing

[christlunalover]

@Color1377 Yes they are

[nfexp]

@Color1377 No they are not...

If we would be amazing we wouldn't kill each other in senseless wars, we wouldn't suffer from hunger and incurable diseases....it seems that you mix up Star Trek with the Reality...

[93zee]

@Color1377 are you alien then?

[fattoldpig]

"according to Einstein" LIGO will never ever detect a gravity wave using lasers, the speed of light changes with space-time contraction/compression and no change will be noticed by an observer who is A PART of the event.

[ItCameFromTheSkyBeLo]

There not measuring the speed of light, there measuring the interference with the light waves. Two waves placed perfectly on top of each other so they the peaks and the troughs of each are opposite each other. Thus canceling each other out, the gravity waves should, as predicted by Einstein, should cause the waves to faulter and show light at the detector.

[Onetoomanysodas]

Even still, it seems there would be much error in calculating the gravitational waves from the difference in the photon packets. The tiny space-time ripples from outer space are so small that it's hard to measure these gravitational waves from Earth and be accurate at calculating the source. LIGO's future solar system observer will be much more precise at measuring these waves and triangulating the source.

[Onetoomanysodas]

By the way the solar system observatory is called LISA

[intindse]

ah come on i wanna se the experiment

[jonrv58]

Space 'shape' is 3d space which we visualise using a 2d rubber sheet (a depression in the sheet caused by a weight -mass-). Gravity wells.

For the Earth and stars they are generally circular and move around in concert with orbits etc. We should remember that these depressions are 3d (spherical) and shape SPACE.

Gravity waves are "shapes of space" also. However they originate from sudden changes in mass configuration... just like ripples on water. continued

[jonrv58]

So, for 'wells' eg from the moon or the Earth there is a change of shape of space that centers on the mass. Gravity waves however are ripples radiating away from a sudden disturbance (explosion) or from movement of the mass [like ripples from a speedboat]

Both are shaped space but very different eg the shape of a whirlpool compared to the ripples from an exploding mine :) The ripples though are spherical in 3d space. continued

[jonrv58]

OK, so instead of waves - ripples - think waves that stretch and compress. So space gets stretched and next compressed and next stretched and so on.

So if you place 2 detectors that are separated one will have space stretched or compressed whilst the other has not - as the waves pass by. Compare the 2 and there you have it... a detection!

SNAG!!! ... this is now opinion: The disturbance to shape is 4D not 3D. Gravity Wells are 4d. Gravity Waves are 4d

continued...

[jonrv58]

So time also gets stretched. The result is that it will be impossible to detect gravity waves by LIGO. The increase in distance cannot be measured with light as an increase in distance will also stretch a second. This prediction of failure was made by myself years ago. Time will tell.

[MuddleVanHeck]

That's fascinating!

[anarchopinko]

Not quite right. You must take into account that light moves on the null geodesic while the mirrors move on massive geodesics - in other words they are affected by GWs differently. Your confusion is common and there are papers that answer this in mathematical detail using GR.

[jonrv58]

Ok. Light moves on the null geodesic. The mirrors move on timelike geodesics (being mechanically held).

The light and the 'objects' are, in conventional GR, influenced differently by a gravity wave. That difference is measurable - being the point of LIGO!

My point is that time WILL alter. That is 'timelike will be the equivalent of Null.

Ok, nonsense? lol. we'll see.

[ItCameFromTheSkyBeLo]

Its not the mirrors that will change, its the lengths of the arms. that will slightly distort the waves of light.

[anarchopinko]

Not quite right. The mirrors are freely falling objects that will move on the massive geodesic which in turn will put the outgoing beam and the incoming beam out of phase. Johrv58, if you go through the math you will see that the time component is taken into account.

[airc123]

Yea If they did not move the same you would never get the same signal from both LIGO locatations!!

[airc123]

The mirrors move the same distance any where on the earth

[airc123]

In the vidio they say that the mirrors move more as you make the system bigger. This not so the deflection of the light beams gets bigger. The mirror movement is the same.If you have a small deflection angle then the farther you loom at the end point get large!

That is what he ment to say!

[martseem]

THIS A GOOD IDEA

[xerochaos187]

this is how we get a map of the waves. we can then use thes waves we have recorded and understand to do the same thing they did to the lazer light "canceling out" local gravity in a feild.........can see what im saying?

[airc123]

From David Infante of Laser Physics:

Well the ligo project is at the same stage as when we thought the earth was flat!!

If you are measureing a space time distortion

YOU DO NOT NEED A OLD TIME AIR SPACED INTERFORMETER! Large vacuum systems etc this is ridiculous. This is so stupid and I cant belive they got the funding for that project. Because it is so massive the frequency responce is low! I would rather they spent the time to measure high frequency GW for talking to ET'S call 706 870 4150

[anarchopinko]

You don't know what you are talking about. Any tiny variation in the recombined laser will show up as a phase variation. If both interferometers pick up a known wave form (theorized wave form) then its a Gwave.

[airc123]

Well The other problem with the LIGO is that the space inside the vacuum chamber also will change.Therefore The phase will stay the same!

The end mirrors move but also the space in the chamber. So the result will be the same!

They do not tell you that at LIGO but all the scientist know this will happen. If the space between the mirrors move,then the wavelength will change to keep C (the speed of light)constent!This will give you zero phase change of the two legs!

[anarchopinko]

The key here is that there are changes in distance between two points whose coordinate separation remains fixed -- the fixed coordinates, in which the mirrors do not change position are the coordinates for massive particle geodesics, while the distance measured by the light is found by the condition of propagation on a null geodesic.

[airc123]

You are still missing the point! You are useing a two dimensional math.This is a four dimensional distortion xyz and time!The fact that the space between the mirrors cahnge! This causes the wave length to change and you end up with zero phase change between the two legs of the LIGO system!As to Null Geodesic this is a meaningless phrase!Is this like a flux capactor phrase like they used in Back to the Future the movie. The propagation of EM waves (light)will be changed through the hole system.

[anarchopinko]

Airc123, What? If a cube is distorted spatially in 3D the face lying in the xy plane distorts - the gwave has two polarizations. You say Geodesic a meaningless phrase? lol. It is just a fundamental property of GR - it is the path taken by matter and energy through spacetime and it is very important and very real. The light will be affected differently than the mirrors - this is basic GR. Please don't say anymore until you pick up a GR textbook.

[airc123]

The LIGO project is a scam! Believe what you want!You need to take more math courses.

Good luck!

[anarchopinko]

airc123 - I need to be taking math courses? I sent you the math and you haven't been able to show where the author went wrong. You made stupid statements like "using 2D math for a 4D distortion" (Projections anyone?). And I understand your arguments and they are flat out incorrect and show that you do not understand Einstein's general relativity at all. Ladies and gentlemen - don't believe laser boy here - he has made so many fundamental errors in his analysis that I am embarrassed for him.

[r06u3AP]

Besides, we already have a wonderful 'gravity wave' detector. It's called 'tides'.

I feel pretty safe in assuming that the H2O molecules in the oceans move quite a bit further than a nuclear width.

A third of a billion dollars spent on LIGO, but it can't even see the MOON???

Tell me this isn't a government project!

[ShaolinSKunk]

You don't know what you're talking about.

[r06u3AP]

LOL! Probably not, but that's never stopped me before!

OK, so please tell me, where am I going wrong here? Thanks!

[NsaneNtheNbrane]

You're right about tides, but they only detect changes in intensity and direction of the Moon's gravitational pull. We need an instrument that can measure the expansion and contraction of space-time as gravitational fields/waves move.

[r06u3AP]

OK, but isn't that the same thing? I mean, gravity is gravity! Curvature of spacetime to some degree of intensity!

That's OK, though. I now have a much better understanding of what they're doing with LIGO, and the arrangement they're using just won't see such slow variations in spacetime due to how it's built. LISA will detect the moon's influence, I'm sure, along with a lot of other interesting things.

[NsaneNtheNbrane]

The apparent force of gravity is an effect of curved space-time. Tides do indicate changes in the curvature, but LIGO's goal is to measure gravity waves another way by observing the curvature more directly. LIGO is designed to observe the actual shape of space-time rather than the apparent force. I agree with you about LIGO's flaws. I hope LISA will be more successful, but I have my doubts.

[anarchopinko]

Why not?

[r06u3AP]

Just one problem - the spacetime interval is frame invariant. Which means that you can't use a local speed of light measurement in an inertial frame to detect changes in interferometer arm length (or, equivalently, changes in light speed). That would mean that the laws of physics change according to gravitational intensity which would violate Relativity.

[anarchopinko]

Not right. Light travels on the null geodesic while the masses are on a spatial geodesic. In other words they take different paths through spacetime and thus are affected differently by perturbations of spacetime.

[r06u3AP]

Quite right, and my apologies for the lack of understanding on my part regarding just how they were differentiating between the null geodesic of light and the mass geodesic, at the time I posted that comment.

[thelfay6]

This is Grandma........you are sooooo smart and to think part of my blood flows through your veins......do not understand but then I am not a college graduate....hahah only from the one of hard knocks....

Hope you and your beautiful wife are doing well........remember that we love you.

Pa pa and Grandma

[mileswaldron]

Something seems wrong, and I don't understand. Can anyone explain to me why the waves of light in the interferometer are not distored by the gravity wave? Wouldn't this just cancel out exactly, so the interferometer would never detect anything?

[dabuddha669]

hey, look at the deep field view f galaxies. you can see the light behind them is very warped bc of the immense gravity. what more is there to know and discover? you can already detect the "waves"

[patchshorts]

They aren't speaking about how light is warped by space. The general idea is to understand what gravities effects are. We still don't know how gravity works. This can lead to research on many useful inventions regarding anti-gravity fields.

[manolis1080]

ya sure i have to work one million years to earn just 1% of the money spend building and operating that "observatory" but they say its "usefull" uao it detects waves of gravity! so in lets say a million years we go conquer the Galaxy right ? so whats in it for me the poor?!!!

[elhmbre00]

Exactly the same question was asked when scientists explored the mysteries of electricity. If the science had been abandoned because the money spent could have been better used on "me the poor" you would still be lighting your hovel with tallow and dying of old age at 34...assuming dysentry ( no sewerage pumps), salmonella (no refrigerators) or syphilis (no bio industry) hadn't killed you first.

[manolis1080]

you aint smart mister elhmbre00 cause electricity was discovered with the help of amature scientists mostly like the ancient Greeks at 1st and then Alesandro Volta using only scrap material like frog's legs not billions of dollars!

[elhmbre00]

Do you really think the first power generating station and distribution system was built from frogs legs? You're not really very bright are you? Maybe that's why you are so poor and cannot afford a dictionary.

[manolis1080]

hei elmbre00 !i m not saying that there wasn't any cost or reaction against building some of the first electric generating stations but there was a obvius potentiantial of using the electricity produced to power home appliances like electric lamps, but what is the direct potential for the puplic after the discovery of any "gravity wave"?.. :( a big round ZERO (as for my incorectness in some words i would say i m not a "native" english speaker and not a philologist like you hahaa:)

[manolis1080]

also remeber electicity was discovered using only simple matterials like magnets and wires or batteries made of frog legs or even lemon juice! not billions of hard earned $!

[pradeeptubeu]

Awesome! Thanks for sharing!

[orangeblueandlavenda]

so,like can you meassure the mutiverse by this observatories ideals,by a simple observation of scale in a transposed sort of thought? Such as like these waves are on this scale in commarison to our universe, so the multiverse must be on this sort of a scale as comarison/relation to our universe?

[DanMitchellFilms]

I think its ridiculous because the Big Bang never happened... they just made another excuse for not believing God created this world, God DID create this world and everything in it!

[hoodwinkedfool]

go away, you take the fun outta life

[elhmbre00]

ignorance is bliss eh ?

[kenotube]

Since gravity waves move only at the speed of light, and since the known universe is billions of light years in size, the cosmic events being recorded (at least those of significance) will be few and far between. What are they looking for? Won't it all look pretty much the same nearly all the time, with many lifetimes between significant events?

[BrunoTheQuestionable]

When the Advanced LIGO upgrade is complete, it will be able to detect the inspiralling and merger of a neutron star with a black hole up to a range of over 1 billion light years. The larger the volume within its range, the more frequent will be detectable events. Many events are expected per year, depending on the mass of the objects.

[kenotube]

Thank you for explaining that. I have 2 other questions: 1. The gravity waves from the big bang traveled outward at the speed of light. All mass generated in the universe traveled outward less than the speed of light. Wouldn't those gravity waves all be traveling away from the earth (and all other matter) and not be able to be recorded? (cont'd)

[BrunoTheQuestionable]

The big bang and the expansion of the universe is not like a conventional explosion that we're familiar with. Its space itself that is expanding and the GWs propagate within that space. Its very similar to the Cosmic Microwave Background - namely a Cosmic Gravitational Background, which should approach us from all directions. Its a bit tricky to visualise :)

[kenotube]

(cont'd) 2. Since the two LIGO's are 2,000 miles apart and the earth is curved, the orientation of the LIGO tubes won't match. Therefore the wave interpretations won't match. Not knowing the direction the waves are coming from, how do they factor this in to synchronize the waves? As the earth spins, the orientation continues to change. Do they use multiple readings at different times of day to calculate direction and intensity?

[BrunoTheQuestionable]

LIGO events will also be correlated with GW obsevatories in other parts of the world. The different orientations (as well as the Earth's rotation) will help localise the direction and polarisation of the GWs. The coincidence of the events will also confirm that they really are GWs and not local disturbances.

[kenotube]

Thanks again. The universe, and science are amazing! I love this stuff.

[RoadRunnerLaser]

Wow. The world's largest Michelson Interferometer !!!

Awesome. When I built my little primitive device from a DPSS, two FSMs and a beam-splitter cube, I had to align everything by hand (I have no optics bench.. boohoo). I know just how darned critical the alignment is to make a simple tiny system work. The tolerances to make this work must be almost unimaginable. It's great to see that incredible structure from an aircraft.

[BabyEngineer]

WOW, 3.02-3.08 there is my supervisor working in the lab where I spent 6 months! Also from 3.50 to 4.03. Fantastico!

[BabyEngineer]

Hi Bruno, I'm studying at LIGO (Caltech, Pasadena) since march 2007, here I'm working for my Master thesis. This video is very useful! Thanks for posting it. In 2 weeks I'll go back home, sigh!

[BrunoTheQuestionable]

I hope the thesis is going well. What's happening with the LIGO observatories at the moment ? There isn't much news on the website.

[Plpoo]

there is no such thing that gravity waves, do you people got crazy?

[RoadRunnerLaser]

Since when did you develop the idea that you are smarter than Einstein ?

[untungsky]

so..? if you guys found and calculate gravitational waves.. what will it bring to us? Whats the benifit? so whats that for? leave that damn gravity alone.!

[PaulJarcobix]

I have a question which may sound like a newbie to physics, please enlighten me, If there is a finite amount of energy in univers (law of conservation of energy) wouldnt all the waves cancel each other out? If so, then minute waves may be undetectable since they are cancelled out immediately?

[BrunoTheQuestionable]

Gravitational waves behave in a very similar way to light waves. To completely cancel a wave it is necessary to add another "mirror image" wave travelling in exactly the same direction, so that the two waves sum to zero. This is a very unlikely occurence. In fact the "zero frequency" component of all the waves will add together to create the local gravitational field.

[GravityExNihilo]

One of my friends works on LIGO, it's pretty much the common consensus that LIGO will not detect anything, even doubtful with the advanced LIGO upgrades. LISA looks more promising.

[tangnatalaga]

Okay, they built this thing to measure gravity wave. Well? have they measured it? What is the frequency? It seems like they are beating around the bush, I wanna know the frequency of gravity here on earth. Have they measured any gravity wave yet?

[Escuerd]

Gravity "here on Earth" doesn't have a frequency. Earth's gravity is basically a constant. What they hope to detect with LIGO is gravity waves from much more massive objects accelerating much faster, like the inspiral of two stars it showed.

They haven't found anything yet because the noise is too high and the "advanced LIGO" upgrade hasn't been completed yet. It should add about two orders of magnitude in sensitivity which puts it in the range needed to search for realistic waves.

[GravityExNihilo]

Gravity waves have extremely low frequencies.

[prabathpeiris]

Ligo is now operating its design sensitivity. Actually LIGO design as a prototype but it works better than we expected, and these days LIGO is operating its full capacity and we will see very interesting results. Well, Gravitational Wave astronomy just begun. in the future it will advance tremendously. Will look at LIGO's initial stage as Edison's first light bulb, it was just a beginning of new era. The frequency that LIGO is operating now it about ~10^-22m.

[tangnatalaga]

you want to build it in space, and you have to send a rocket up there to send materials, and that would be very expensive. Will you at least think for a while before posting a comment?

[prabathpeiris]

well, its already under construction. check "Laser Interferometer Space Antenna", gust google it.

[tangnatalaga]

Thats why they suspended the mirrors, and all that so that noise, and vibration do not interfere. Why don't you watch, and listen before posting something?

[fiftycaliberfistfuck]

I'm all for science, but this is a huge waste of taxpayer money, a subsidy for the rich. So, you measure the existance of a gravity wave passing by, it tells you nothing. Not the direction it came in, nor can you do anything with the data. All it does is prove space can be bent. Once you know that, which we pretty much already know, you're stuck with a multi million dollar installation that is a useless piece of equipment, while thousands starve worldwide and we get taxed out the ass.

[GravityExNihilo]

Of course we'd rather spend billions on bombing those countries.

Science is hardly a well-funded field. If we never find G-waves then it might mean the theory is wrong.

[wganderson]

What? Of course we can tell the direction that a gravitational wave came from, provided we have at least three non-colocated interferometers to work with (currently there are five operating). And there is a lot that we will be able to say about the universe from gravitational wave observations - it will inform population models, reveal the structure of spacetime around black holes, and give important information about the composition of neutron stars, among other things.

[cobrachoppergirl]

So if you know the structure of spacetime around a black hole and something more about netron stars, what good will that do you? Like the guy said, you can't feed people with that. If you know a star far away is purple rather than green, yes you know something more about the universe, but was it worth spending millions to find out? And yes, the military is an even huger waste of money, which besides killing people, often drives science to find new and more devilish ways of killing people.

[wganderson]

So your position is that pure science (as opposed to applied science) is a waste of money? That is a tempting argument ,but it is short-sighted. Pure research gives applied research tools to work with, and it does so in unexpected ways. Who knew over 100 years ago when Planck postulated that light comes in quanta that it would lead to microprocessors, lasers, etc that have saved millions of lives? Also, are you opposed to spending on the arts? After all, you can't feed people music or paintings.

[anarchopinko]

The military spends 350 billion or so dollars a year. Compared with that science is chump change. Also, the pursuit of knowledge in science has virtually lead to all technological achievements we have today - your computer for example.

[BrunoTheQuestionable]

You're absolutely right - they're doing it - its called the LISA mission (I posted a video).