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Gravitational Waves May Have Been Detected In 1987

timothy posted more than 5 years ago | from the and-you-know-what-the-monkeys-may-do dept.

Space 221

KentuckyFC writes "In 1987, a physicist called Joe Weber claimed to have detected gravitational waves at the same time that other scientists spotted a supernova called SN1987A. His claims were largely ignored because of calculations showing that gravitational waves could not be strong enough to be picked up by Weber's equipment, a set of giant aluminium cylinders designed to vibrate as the waves passed by. But these calculations were based on first order effects in the way spacetime can be distorted. Now a new analysis shows that second order effects can enhance gravitational waves by four orders of magnitude, but only when certain asymmetries are present. It turns out that SN1987A possesses just the right kind of asymmetries to make this enhancement possible because the supernova wasn't entirely spherical. Which means that Weber, who died in 2000, may have been the first to see gravitational waves after all."

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Honor (4, Funny)

AKAImBatman (238306) | more than 5 years ago | (#27067907)

Gravity waves? I thought they'd never be observed! Impeller Drive [wikipedia.org] , here we come! Now all we need is to prove hyperspace as a viable means of travel and invent Warshawski sails. :-P

(Joking aside, this is great news! Gravity waves have been one of the most difficult aspects of relativistic physics to pin down.)

Re:Honor (4, Insightful)

dk90406 (797452) | more than 5 years ago | (#27068143)

This is not great news. This is (great) speculative news. It is interesting and inspires hope, but I seriously doubt that the scientific community will accept this as proof.
We are talking '87 and there are too many unknowns in the experimental setup, that no-one can clarify now. Did a truck drive by here in '87?

Re:Honor (3, Insightful)

Brian Gordon (987471) | more than 5 years ago | (#27068369)

The problem is that you can't exactly reproduce a supernova..

Re:Honor (4, Funny)

_Hellfire_ (170113) | more than 5 years ago | (#27068539)

Well there *is* this star close by...

Re:Honor (4, Funny)

Animaether (411575) | more than 5 years ago | (#27068993)

[10:01:14] This is the sun that Earth is orbiting. It's a regular main sequence star with a core temperature of about sixteen million degrees and enough hydrogen to burn for another five billion years.
[10:01:27] Yeah?
[10:01:30] We wanna blow it up.
[10:01:38] Wow.
[10:01:42] That's, uh...
[10:01:47] Ambitious.
[10:01:47] Ambitious.

Re:Honor (3, Funny)

Anonymous Monkey (795756) | more than 5 years ago | (#27069071)

So, all we need is a black hole, some alien technology, and a friendly snake in my head?

Re:Honor (0, Offtopic)

Tubal-Cain (1289912) | more than 5 years ago | (#27070161)

And some friends that need rescuing before the star goes nova, because one of them is rather fixated on getting revenge on $BADGUY.

Re:Honor (0)

dk90406 (797452) | more than 5 years ago | (#27068675)

True. But we don't need to. Just insta-travel(R) 23 LY in the direction away from the Supernova. Wait there for less than a year and repeat the experiment. The waves will be a little weaker, but that would be negligible.

Re:Honor (1)

Brian Gordon (987471) | more than 5 years ago | (#27069747)

Don't they propogate at the speed of light?

Re:Honor (0)

Anonymous Coward | more than 5 years ago | (#27069951)

That's why we'd need to travel those 23 lightyears by non-relativistic means.

Re:Honor (2, Funny)

PolygamousRanchKid (1290638) | more than 5 years ago | (#27068829)

Be thankful for that. In another 1,000 years, someone will post simple instructions on how to create a supernova in your basement on the InterGalacticNextGenerationNet (powered by IPv9). And someone will download it, do it, and, for whomever is alive at that time, things will not be very pleasant.

I'd personally hold out for the Gamma Ray Burst recipe. Now *that* would be cooler than an M80 flushed down the toilet, but equally unpleasant, if you happen to be in the path of the gamma rays.

Although this is intended on the lighter side, try to imagine a time in the future, where we can safely pull of stuff like this.

Yo.

Re:Honor (3, Funny)

Brian Gordon (987471) | more than 5 years ago | (#27069805)

And to think at one time people naively thought 128 terabits of addressing space was enough.

Re:Honor (1)

Magee101 (1492127) | more than 5 years ago | (#27070103)

Well true that you can't reproduce an event that equals the size and destructive force of a supernova, the atomic/hydrogen bombs built back in the 40's-50's were based on what -causes- a supernova. All we'd have to do is take the readings from the test explosions of the largest bomb used, and then multiply the pressure/gravitational waves to the level of a star going boom. Not that hard

Re:Honor (0, Troll)

Anonymous Coward | more than 5 years ago | (#27068753)

It is interesting and inspires hope

Hope? In me it mostly inspires contempt for the 'scientists' involved.

"No, whatever you think you observed, it can't have happened because it isn't consistent with our theory"

Some years later...

"We've found a way to reconcile your observations with our theory - so you can have been right after all!"

The is the exact opposite of what science is supposed to entail. Truly appalling.

Re:Honor (2, Insightful)

dk90406 (797452) | more than 5 years ago | (#27068901)

No. This is the way science is supposed to work. If something doesn't fit existing theories, it will (and should) be subject to skepticism, until new scientific theories are produced, that may support your observation.

Re:Honor (5, Insightful)

TheRaven64 (641858) | more than 5 years ago | (#27069075)

No, science is supposed to be a process of observe, hypothesise, test, repeat. You can discard theories that don't fit hypotheses, but discarding observations because they don't fit theories is the exact opposite of science. This is the kind of behaviour I would expect from people preaching intelligent design, not from anyone who deserves the title of scientist.

Re:Honor (1)

gomiam (587421) | more than 5 years ago | (#27069189)

...but discarding observations because they don't fit theories is the exact opposite of science.

Of course, discarding observations because the error margin was then considered too big makes a lot of sense. That is what happened.

Re:Honor (4, Insightful)

Mr. Underbridge (666784) | more than 5 years ago | (#27070263)

Of course, discarding observations because the error margin was then considered too big makes a lot of sense. That is what happened.

The theory that was used to reject the observations was the same one being tested. That's circular. God forbid anyone actually inject reality into that feedback loop of the purely theoretical.

I can't tell you how many times truly new knowledge about the universe was ignored because the scientific orthodoxy claimed "that *can't* be right" based on nothing but assertion.

Re:Honor (1)

Lord Ender (156273) | more than 5 years ago | (#27070237)

You are both right. Skepticism is key to science (see: peer review, falsifiability requirements). So is the process you mentioned. Without both, science is worthless.

Re:Honor (1)

Rostin (691447) | more than 5 years ago | (#27070253)

There are no golden plates handed down from on high telling us what science is supposed to be like. Science as it is practiced by working scientists is complicated, and it often bears only a passing resemblance to the idealized "scientific method" you learned in elementary school.

Sometimes we are completely justified in throwing away or shelving observations that don't fit with established theories. In the real world, experimental observations can't be neatly disentangled from scientific theory. To test a hypothesis, we must first assume the reliability of a set of laws or theories. If something goes contrary to expectation, it might not be clear why. Is the problem with the hypothesis, or is it with one of our assumptions? Could the experimenter have made an error without realizing it? Could he be dishonest? We have finite time and resources and lots of other research problems.. How much should we invest in sorting this all out? It's just not as simple as, "We possess facts 1, 2, and 3, therefore Theory A is false."

Re:Honor (1)

LiquidAvatar (772805) | more than 5 years ago | (#27069971)

Funny... I always thought it was the other way around. If an observation contradicts the dominant theory, I thought the theory should be revised, not the observation.

Re:Honor (0)

Anonymous Coward | more than 5 years ago | (#27070395)

If an observation contradicts the dominant theory, I thought the theory should be revised, not the observation.

Isn't that what the GP said?

If something doesn't fit existing theories, it will (and should) be subject to skepticism, until new scientific theories are produced, that may support your observation.

Re:Honor (3, Insightful)

Goaway (82658) | more than 5 years ago | (#27068983)

No, that is exactly how science is supposed to work.

Re:Honor (0)

Anonymous Coward | more than 5 years ago | (#27068943)

No, this is wrong, as a matter of principal.

The paper was considered methodologically sound, but incorrect, in 1987. There are not "too many" experimental unknowns now, or else the paper would have been considered invalid then. After all, this experiment can't be reproduced, even in principle. The only way to gather any information out of a single observation is to use sound and detailed experimental and observational methodology to logically isolate as many known "independent" variables as possible.

If others collected data in similar units, they could potentially corroborate the analysis.

You can even put upper bound estimates on the error, from a single observation. (Specifically because we have "lots" of observations of our equipment, the "known" laws of physics, etc)

Re:Honor (2, Interesting)

rpjs (126615) | more than 5 years ago | (#27068549)

But if this Weber (Joe) detected the gravity waves at the same time as SN1987A lit up, the Honorverse has a major problem as that Weber (David) assumed that gravity waves would be FTL.

Re:Honor (1)

AKAImBatman (238306) | more than 5 years ago | (#27068875)

As I recall, only the grav waves traveling through hyperspace were FTL. So grav waves could be read by sensors at superluminal velocities, but the impeller drive functioned on the light-speed grav waves. I think. :-P

Re:Honor (3, Insightful)

Anonymous Coward | more than 5 years ago | (#27068979)

and at what speed do you presume the light emmited from this supernova made its way to earth, if they arrive at the same time, they are both going at a speed they should be going

FTFS (2, Funny)

Anonymous Coward | more than 5 years ago | (#27067909)

In 1987, a physicist called Joe Weber...

So, what was his real name? Also, editors, the last statement of your summary is a sentence fragment. Please fix this.

Re:FTFS (2, Funny)

elrous0 (869638) | more than 5 years ago | (#27068635)

Actually, you're wrong. There is clearly supposed to be an "and" before "claimed." The physicist who called Joe just wishes to stay anonymous at this time.

Re:FTFS (1, Informative)

Anonymous Coward | more than 5 years ago | (#27069013)

Actually, his real name was not Joe Weber. From wiki:

'His name was "Yonah" until he entered grammar school. He had no birth certificate, and his father had taken the last name of "Weber" '

It's also interesting to note that Joe Weber was not a second rate physicist, having studied at the Institute for Advanced Study in Princeton with no less a luminary than John Wheeler, who himself published with Einstein.

Re:FTFS (0)

Anonymous Coward | more than 5 years ago | (#27069809)

There are no second rate physicists. Einstein was/is an overrated media golden boy, he barely grokked linear algebra.

Re:FTFS (1, Informative)

Anonymous Coward | more than 5 years ago | (#27069049)

In 1987, a physicist called Joe Weber...

So, what was his real name?


In your race to show your superiority, you neglected to do a little background reading on the subject.

"Weber was the youngest of four children born in Paterson, New Jersey, to Yiddish-speaking immigrant parents. His name was 'Yonah' until he entered grammar school. He had no birth certificate, and his father had taken the last name of 'Weber' to match an available passport in order to emigrate to the US. Thus, Joe Weber had little proof of either his family or his given name..." (from the link provided in the Slashdot summary [wikipedia.org] )

So yes, he was called Joe Weber.

Re:FTFS (0)

Anonymous Coward | more than 5 years ago | (#27069133)

Actually, his father emigrated from Europe and used a passport with the name Weber, well because he had one. Joe's real first name was Yonah, and he adopted Joe as his name for school.

So, yes he was called Joe Weber, but that was probably not his 'real' name.

link to wiki http://en.wikipedia.org/wiki/Joseph_Weber#Personal_life [wikipedia.org]

Re:FTFS (0)

Anonymous Coward | more than 5 years ago | (#27069763)

His parents started out calling him Yonah, and his dad took on the name Weber in order to emigrate to the US. He had no birth certificate. He didn't become Joseph Weber until he started going to school.

Dude, (4, Funny)

OneSmartFellow (716217) | more than 5 years ago | (#27067959)

...where's my surfboard ? I'm totally stoked, I want to be the first to ride a gravity wave, that'd be, like really heavy, man !

Re:Dude, (3, Funny)

boarder8925 (714555) | more than 5 years ago | (#27068657)

There's that word again. "Heavy." Why are things so heavy in the future? Is there a problem with the earth's gravitational pull?

Re:Dude, (4, Funny)

linzeal (197905) | more than 5 years ago | (#27068807)

Americans importing half of the solar systems foodstuffs have grown so large that the average city block in the 20th century barely contains the girth of one 5000 ton Homo Americanus Gigantus. This displacement of mass has caused a localized gravitational disturbance in the curvature of spacetime large enough that places like the former state of Texas are now 200 feet below the 2000 BCE sea level. If it wasn't for the mile high tall walls with lasers on them surrounding the US to keep out aliens it would be completely underwater except for parts of Colorado.

Re:Dude, (0)

Anonymous Coward | more than 5 years ago | (#27069855)

Americans importing half of the solar systems foodstuffs have grown so large that the average city block in the 20th century barely contains the girth of one 5000 ton Homo Americanus Gigantus.

We must elect BARAKUS!

Only he can give the solar system the redistribution of fat that it so desperately needs!

Nobel prize (4, Interesting)

Alain Williams (2972) | more than 5 years ago | (#27067969)

Can this be awarded posthumously ?

Re:Nobel prize (-1, Offtopic)

MyLongNickName (822545) | more than 5 years ago | (#27068003)

Yes. But you cannot be nominated posthumously. So in this case, the guy is out of luck.

http://nobelprize.org/contact/faq/index.html [nobelprize.org]
(sorry for not using a wikipedia link)

Re:Nobel prize (4, Informative)

Bwian_of_Nazareth (827437) | more than 5 years ago | (#27068115)

No, I am afraid you are not right. It specifically says that you cannot be awarded the prize posthumously... Effective from 1974, the prize may only go to a deceased person to whom it was already awarded (usually in October) but who had died before he/she could receive the Prize on December 10.

Re:Nobel prize (1)

obliv!on (1160633) | more than 5 years ago | (#27070311)

Rosalind Franklin is a prime example of the fact that the noble prize is not awarded posthumously.

Re:Nobel prize (2, Informative)

MyLongNickName (822545) | more than 5 years ago | (#27068209)

Please mod my post down. It is not informative. It is actually wrong as pointed out by others.

Re:Nobel prize (1)

marnues (906739) | more than 5 years ago | (#27070227)

No no no. Please mod up. That's one of the most informative and straight forward threads I've ever seen on /.

Re:Nobel prize (0)

Anonymous Coward | more than 5 years ago | (#27068015)

Afraid not.

Re:Nobel prize (2, Informative)

Bwian_of_Nazareth (827437) | more than 5 years ago | (#27068053)

No, it cannot. See Nobelprize FAQ [nobelprize.org]

Suck my cock for a special prize (-1, Troll)

Anonymous Coward | more than 5 years ago | (#27068093)

You can enter the contest as often as you like.

Re:Nobel prize (4, Informative)

doconnor (134648) | more than 5 years ago | (#27068119)

No Nobel Peace Prize was awarded in 1948 because, "there was no suitable living candidate". It's generally believed that Mahatma Gandhi would have got it if he had not been assassinated on January 30, 1948.

Re:Nobel prize (-1, Troll)

Anonymous Coward | more than 5 years ago | (#27068287)

Did you know that Obama is a bigger baby killer than Sebelius? Did you know that this effort, if anything, will make Sebelius MORE in line for a job? If you look with eyes to see, you will see that as he points his finger and insists upon his will, looking for a short while like a calm and friendly father figure, you will see the blood that DRIPS from his fingers.

Shortly, his phony faÃade of peace and kindness will fall away and the face of the monster that he is will appear. He will speak peace, but in his heart, he is for war! His father the devil will see to his power base, and all these notions that the people are being heard, or that he is for the people, will become a thing of myth. The fags will be his right and left hand and when he begins to engage in war, for real, the sight will be so grim and horrifying that the nations that have fawned all over him will, from sheer terror, shut their mouths and come under the yoke, and THAT will be the face of this:

Rev 13: 4 And they worshipped the dragon which gave power unto the beast: and they worshipped the beast, saying, Who is like unto the beast? who is able to make war with him?
5 And there was given unto him a mouth speaking great things and blasphemies; and power was given unto him to continue forty and two months.

But you see, the very next verse ends with a plain statement of the shortness of his time!

Antichrist Obama is looking for murderers to fill his posts. She is perfect for his army. She will go nicely with the Rod of Ham - Hillary in carrying out the policies of her master, and her father, His Majesty The Devil!

So with that clear, do you not think that you should put away these lame and misdirected efforts to get a ground swell of righteousness in a nation FILLED with people that hate God and are in EVERY good work reprobate, and begin to focus upon your OWN never-dying soul and serve the Lord your God in TRUTH â" turning not aside to the left hand NOR to the right hand? Fulfill the Royal Law according to scripture, that is, to love your neighbor as yourself, which is â" warn your neighbor at this VERY late hour to FLEE the wrath to come, that is, GET ONTO THE STREETS and say the words â" that is, PICKET!!

Thanks!

Re:Nobel prize (0)

Anonymous Coward | more than 5 years ago | (#27068407)

Adults with imaginary friends should be given medical help, not political power.

Re:Nobel prize (1)

matt_hs (1252668) | more than 5 years ago | (#27068995)

John McCain? Is that you?

Re:Nobel prize (1)

Hellpop (451893) | more than 5 years ago | (#27069329)

Obama has an imaginary friend too. Who it is just depends on who you ask...

Y'know, somehow I doubt that is his only imaginary friend.

Waves? (5, Funny)

imajinarie (1057148) | more than 5 years ago | (#27068089)

And here I was always convinced they were Gravity Particles.

Re:Waves? (1, Insightful)

Anonymous Coward | more than 5 years ago | (#27068375)

If they're anything like light, they're both.

Re:Waves? (5, Funny)

girlintraining (1395911) | more than 5 years ago | (#27068617)

And here I was always convinced they were Gravity Particles.

The lawyers for the Standard Model called. They mentioned something about a Cease and Desist Order: You're not allowed to discuss gravity around anyone schooled in quantum mechanics-- It apparently causes emotional duress.

How much (4, Insightful)

MyLongNickName (822545) | more than 5 years ago | (#27068105)

How much does it have to suck to die, with your observations being discredited, and your claims laughed at? Then a decade later, the scientific community goes "oops, you were right".

And now, in Slashdot's infinite wisdom, I am required to wait five minutes between posts.

Re:How much (3, Informative)

paiute (550198) | more than 5 years ago | (#27068215)

How much does it have to suck to die, with your observations being discredited, and your claims laughed at? Then a decade later, the scientific community goes "oops, you were right".

This guy had a carrier shot out from under him. I don't think the naysaying of a bunch of geek theorists bothered him much.

Re:How much (3, Insightful)

MyLongNickName (822545) | more than 5 years ago | (#27068289)

I would argue it might upset him more. I mean, this is his work. You do not get to this level without putting a lot of your heart and soul into it. To be convinced that you are on the edge of a major discovery only to have it rejected has to be disheartening.

Re:How much (4, Informative)

Shakrai (717556) | more than 5 years ago | (#27068403)

This guy had a carrier shot out from under him.

For those wondering, he was a crew member of the USS Lexington [wikipedia.org] , which was lost at the Battle of the Coral Sea.

Re:How much (1, Informative)

MollyB (162595) | more than 5 years ago | (#27069129)

The ship that bore the name Lexington was CV-2 and was sunk at Coral Sea. The Lexington lives, however, when CV-16 [usslexington.com] was rechristened Lexington. The Lex is moored in Corpus Christi, TX.

Re:How much (0)

Anonymous Coward | more than 5 years ago | (#27070347)

Get a fcuking clue.

Re:How much (4, Funny)

Anonymous Coward | more than 5 years ago | (#27068231)

I'm sure glad you didn't die during those five minutes. I mean, how much does it have to suck to die, with your post being discredited, and your claims laughed at? Then a decade later, the Slashdot community goes "Oops, you were right" with a +5 Insightful.

Re:How much (0)

Anonymous Coward | more than 5 years ago | (#27068239)

And now, in Slashdot's infinite wisdom, I am required to wait five minutes between posts.

It took you 5 minutes to write that? Funny, how with the power of the internet, I spent less than 5 minutes googling all known organisms on the planet Earth...

Re:How much (0)

Anonymous Coward | more than 5 years ago | (#27069585)

Funny, how with all those l33t sk1lz, you can't fucking comprehend what you read.

Re:How much (2, Insightful)

Em Emalb (452530) | more than 5 years ago | (#27068321)

Probably doesn't suck at all for this guy, I'm sure he doesn't care at all. Maybe his family and friends, but he probably doesn't care one bit.

Re:How much (1)

Bemopolis (698691) | more than 5 years ago | (#27068435)

Ask Alfred Wegener [wikipedia.org] .

Re:How much (1)

BlueStrat (756137) | more than 5 years ago | (#27069307)

Ask Alfred Wegener.

Bah, just ask me!

I invent the time machine, but die before getting credit because some corporation sent an assassin back in time..hold on, there's the doorbell.

>BANG!

Aaagghh!...NO_CARRIER

Re:How much (1)

Kjella (173770) | more than 5 years ago | (#27068525)

How much does it have to suck to die, with your observations being discredited, and your claims laughed at? Then a decade later, the scientific community goes "oops, you were right".

Isn't that what they say about great artists too? IMO it's just bullshit to soothe the 99% who'll remain utterly insignificant after their death too, but it's not like scientists are the only ones not to be understood by their contemporaries.

Re:How much (1)

MBCook (132727) | more than 5 years ago | (#27068569)

Hopefully not too much.

If I die before my Hambuger Earmuffs are finished thought, I may get the opportunity to find out though.

*glaven* warm ears...

Re:How much (2, Interesting)

east coast (590680) | more than 5 years ago | (#27068773)

As a scientist, I would find it a far better thing to have my claims proven correct after my death than to have them declared correct in my lifetime only to be discredited later due to lazy peer review.

Science should be a marathon, not a sprint.

Re:How much (5, Informative)

JustinOpinion (1246824) | more than 5 years ago | (#27068867)

Then a decade later, the scientific community goes "oops, you were right".

Hm. But this raises an interesting question. Was he actually right?

Let's assume for the moment that TFA is correct, that higher-order terms can enhance gravity waves and that this is the case for SN1987A. So Weber's measurements in 1987 contained a valid signature of a gravity wave.

In a sense, then, he did detect gravity waves. And so he was right in saying "I detected gravity waves". However, he may have been right for the wrong reasons. Science works by interpreting data, and convincing others that your interpretation is correct. Weber was not able to do so. He was not able to convince others because he couldn't provide a way to connect the magnitude of the signal in his measurements to the available theory.

Now, if he had done what the present scientists have done, and demonstrate that the higher-order terms make gravity waves detectable in his apparatus, then he might have been able to convince his colleagues. Then he would really have been right (and for the right reasons). But he didn't (as far as I can tell). He incorrectly said "gravity waves, as described by these theories/equations, have been measured on my instrument"... which is wrong.

Some of you may think I'm just splitting hairs or something. But it's important because in science being right is not about randomly guessing the right answer... it's about providing a robust argument based on repeatable measurements. In science, happening upon the right answer using the wrong logic isn't really considered a good thing. As an extreme analogy, imagine that I am trying to predict when the next volcanic eruption will be, and I come up with a complicated theory based on tides. Then I correctly predict an eruption. A few years later some smarter guys come along and create a really great theory that predicts volcanic eruptions, and show that it is really based on magma flow... and that I was just lucky to have predicted the eruption. Was I "right" in my prediction?

Re:How much (2, Informative)

poopdeville (841677) | more than 5 years ago | (#27068977)

That depends on whether there's any causal link between the tide and magma flow. (There is)

Re:How much (2, Insightful)

ShakaUVM (157947) | more than 5 years ago | (#27069591)

In a sense, then, he did detect gravity waves. And so he was right in saying "I detected gravity waves". However, he may have been right for the wrong reasons. Science works by interpreting data, and convincing others that your interpretation is correct.
Not necessarily. There's different things under the title of science, and one of them is black-box science, when you're investigating something that you don't know the slightest thing about, and seeing what happens. We don't know exactly how gravity waves should behaves, so reporting that you detected them (even when the math says you shouldn't be able to), *is* valid science. As Feynman said, experiments trump math.

 

Re:How much (1)

shma (863063) | more than 5 years ago | (#27069059)

How much does it have to suck to die, with your observations being discredited, and your claims laughed at? Then a decade later, the scientific community goes "oops, you were right".

You obviously didn't read the actual paper. This is in no way a rigorous theoretical argument that Weber saw gravitational waves. It's nothing more than a rough order of magnitude calculation. A second look should be taken, but we should not start handing out posthumous awards right away.

And who was laughing at him? Weber was regarded as a pioneer of gravitational wave experiments. You can find a discussion of his work in standard textbooks. You seem to assume that anyone who doesn't succeed in every one of their experiments is summarily drummed out of the scientific community. If that were so, we'd have no scientists left.

The most telling part of the paper comes at the end: "It would also be necessary to check that the predictions of this proposal do not violate the absence of observed gravitational waves from other sources." To me, this 10^4 enhancement factor is probably enough that we'd have seen GW from a variety of sources by now in our more sophisticated detectors (which are interferometers, and are unrelated to Weber's setup), which leads me to be dubious about the claims of enhancement.

Re:How much (1)

khallow (566160) | more than 5 years ago | (#27069107)

The most telling part of the paper comes at the end: "It would also be necessary to check that the predictions of this proposal do not violate the absence of observed gravitational waves from other sources." To me, this 10^4 enhancement factor is probably enough that we'd have seen GW from a variety of sources by now in our more sophisticated detectors (which are interferometers, and are unrelated to Weber's setup), which leads me to be dubious about the claims of enhancement.

But I gather those aren't as sensitive to the second order effects in question, right?

Re:How much (1)

shma (863063) | more than 5 years ago | (#27069583)

But I gather those aren't as sensitive to the second order effects in question, right?

Wrong. The supposed 10^4 enhancement factor is in the magnitude of the GW waves and would be seen by any detector.

Gravity model (3, Interesting)

cyberchondriac (456626) | more than 5 years ago | (#27068493)

One thing I've never liked about the current popular gravity model, you know, the one they discuss on discovery channel, usually for a cosmology special, where they discuss how gravity distorts space-time, and then you get to see a CGI animation of a large ball on a rubber like grid -drawn as a 2 dimensional analogy- and the ball is pushing down on the grid, making an indentation in it, and another, smaller, ball starts circling the bigger ball, eventually falling in towards the larger ball..
Isn't that like using gravity to explain the effect of gravity?

Re:Gravity model (3, Insightful)

tylersoze (789256) | more than 5 years ago | (#27068727)

It's only a very crude analogy. In reality, it's both space *and* time that are being distorted. Gravity causes all the "straight lines" (geodesics) in space-time to become curved. So the Earth orbits around the Sun and a thrown ball follows a parabolic arc because it's actually a "straight line" in space-time that gravity has curved just like a Great Circle on the Earth is a "straight line" (i.e. the shortest distance between two points) with respect to the surface of the Earth.

Re:Gravity model (3, Informative)

inertialFrame (259221) | more than 5 years ago | (#27069753)

It's only a very crude analogy.

That's a good point, and it should be elaborated as the proper response
to cyberchondriac.

cyberchondriac identifies the grid-bent-by-balls as "the current popular
gravity model". It is in fact a popular model, which I remember from
watching PBS even as far back as the 1970s. The good thing about this
model is that it allows one to visualize how a mass both distorts space
and moves in response to the distortion caused by another object. But
its goodness as a model of gravity ends there, in part due to
cyberchondriac's astute observation that it makes use of gravity to
explain gravity. Still, the model is not bad because it uses one aspect
of gravity (that it is nearly uniform near the surface of the Earth) to
explain a *different* aspect of gravity (that distortions caused by
multiple objects can interfere with each other and lead to motion).

In reality, it's both space *and* time that are being
distorted.

Not quite. In reality, the best model that we have is general
relativity, according to which both space and time are being distorted.
But this is not to say that space and time are being distorted in
reality, because we will never know for sure what's going on in reality.
That is, a scientific theory (like general relativity) can never be
proved true, though it can be proved false. Who knows? General
relativity might be ruled out by some future experiments and replaced
with a fundamentally different view of gravity.

Not really. (2, Informative)

AltGrendel (175092) | more than 5 years ago | (#27068749)

They're showing it in two dimensions, when it's actually happening in four. Try and think about that, but be careful. Your head might explode.

Re:Not really. (1)

Neon Aardvark (967388) | more than 5 years ago | (#27068803)

They're showing it in three dimensions. We humans can visualize up to 3 very well. Adding another gets complex.

Re:Not really. (1)

tylersoze (789256) | more than 5 years ago | (#27068921)

Actually you could probably visualize a simple case of one dimension motion with a traditional 2D space-time diagram (1 spatial + 1 time dimension) and curve that into three dimensions. You could at least visualize why a dropped ball would accelerate downwards along a straight line. Starting at 0 velocity (a straight line upwards along the t-axis) that "straight line" would start to curve in the direction of gravitational source, which translates into an increasing velocity (the slope of the curve).

Re:Not really. (0)

Anonymous Coward | more than 5 years ago | (#27069157)

The Human (3D life form) eyes only see in 2 dimensions. You see 2 flat plans if you have 2 eyes. To truly see in 3 dimensions you need to be a 4D life form. Anyone here know what "ever 17" is?

Re:Not really. (1)

Punko (784684) | more than 5 years ago | (#27069627)

BZZT the human body is a 3D object, but exists in time. i.e. the human body exists in 4D - You are a 4D life form. If you wish to state that eyes see a 2d plane, they also see it as it changes in time, i.e. 3D 2 in space, 1 in time. Watching a movie is a 3D experience. Watching a 3D movie is a 4D experience

Re:Not really. (3, Interesting)

Neon Aardvark (967388) | more than 5 years ago | (#27069947)

Er, no, you don't "truly" see anything. Your brain forms a representation of reality based on sensory input. In the visual side of that, the spatial representation is 3D.

Furthermore, you don't "see" in 2 dimensions, in your understanding of the word (which is kinda meaningless, cf visual illusions, hallucinations etc), because of the parallax effect afforded by having two eyes.

Also, the complete internal representation of a thrown ball is fundamentally 4 dimensional (3 spatial + 1 temporal). But it's hard to visualize curvature of 4 dimensional spacetime.

Re:Not really. (1, Insightful)

Anonymous Coward | more than 5 years ago | (#27070269)

Er, no, you don't "truly" see anything.

Yes, I do.

Your brain forms a representation of reality based on sensory input.

Yes. That's what "see" means. So why did you claim that I don't "truly" do it?

Re:Not really. (2, Informative)

tylersoze (789256) | more than 5 years ago | (#27069047)

It's even worse than that. To visualize a curved 4-dimensional space you'd need 5 dimensions to embed it in. Not to mention the fact that time is a different type of dimension so distances are measured differently in space-time. t^2 - x^2 (or "proper time", the time a object would experience traveling along that line) instead of pythagorean x^2 + y^2. So the distance between all points along a light cone is 0 and every outside is imaginary!

Re:Not really. (1)

poopdeville (841677) | more than 5 years ago | (#27069207)

Open your eyes. Visualize all the four-dimensional space you want.

Re:Gravity model (1)

Neon Aardvark (967388) | more than 5 years ago | (#27068761)

It's not trying to explain, it's an analogy that gives an example of how distortion in topology can affect motion.

The reason they use it in pop science programs is it's hard to visualize 4 dimensions of curvature.

Re:Gravity model (1)

cowscows (103644) | more than 5 years ago | (#27068771)

Well if it's a CGI animation, then you're not really using gravity, you're just using fancy rendering. But ignoring that technicality, it's not really that much different than using a substance made out of molecules to build a scale model of a molecule. You're just using what's available to you in order to make a simplified model. There's not any easy and intuitive way to represent some aspects of physics in a manner that relates directly to the normal human experience of the universe. So you have to make a simpler model that starts to bridge the gap between how things appear to work at the scale of a human being and between the physics going on that are generally only visible at vastly larger or smaller scales.

So in the rubber sheet grid example, what's actually happening is that you're using gravity as generally experienced by humans (things roll downhill) to demonstrate some of the more fundamental aspects of that gravity (mass bends space).

Re:Gravity model (1)

Fluffeh (1273756) | more than 5 years ago | (#27069565)

and then you get to see a CGI animation of a large ball on a rubber like grid -drawn as a 2 dimensional analogy

Actually, it's a four dimensional analogy.

You have your x/y dimensions (forwards/backwards,left/right) as noormal, but they have flattened the z (up/down) as it's not important for the visualization. Now, instead of there being an up/down they have used that axis to show gravity.

Trying to draw something in four dimensions and hoping that the audience watching the show will make heads or tails of it would be like trying to nail jelly to a tree.

Re:Gravity model (3, Interesting)

Chris Burke (6130) | more than 5 years ago | (#27069845)

Isn't that like using gravity to explain the effect of gravity?

Sure, but it's just an analogy. It's not supposed to explain why masses warp space-time, only to show how a mass causing space-time to warp gives rise to effect we call gravity. In the analogy, the curvature of the space-time sheet is caused by gravity pulling downward on a ball to create the curve. In the reality the analogy is supposed to represent, the curvature of space-time is gravity. The analogy just gives you an easy way to ignore the "why" that theory can't answer, so you can focus on understanding the effect.

If it makes you feel better, you can just ignore the gravity-pulling-the-balls-down part of the analogy, and replace it with a simple assumption that a ball on the sheet causes the sheet to bend, and that other balls tend to move towards "low" spots in the sheet, with no explanation for why this happens.

those weren't gravity waves (3, Funny)

stoolpigeon (454276) | more than 5 years ago | (#27068495)

it was the pure amazement of my high school teachers that I was graduating. I was pretty shocked too.

I detect gravity waves all the time (2, Funny)

KiwiCanuck (1075767) | more than 5 years ago | (#27068557)

using my tin foil hat.

Poor guy (2, Interesting)

markov_chain (202465) | more than 5 years ago | (#27068785)

What are they going to name the gravity SI unit, Webers? Right...

In 1987, Joe Weber, a physicist ... (1)

b4dc0d3r (1268512) | more than 5 years ago | (#27069225)

Why wouldn't you say Joe Weber discovered this, instead of some random physicist? Is his name Joe Weber or is that just what people called him?

I don't know anyone else named Joe Weber so you would not have to say Joe Weber the physicist to clarify either, although I appreciate the additional information. I would have said maybe a dog called Joe or a robot called Joe, but it sounds awkward and a bit insulting talking about people.

Me, I'm a poster called b4dc0d3r - you don't know if this is a person or machine or bitrot. Joe Weber on the other hand, identifies the person, instead of the watery fleshbag it walks around in. Sure he's dead now, but he apparently didn't get the respect he deserved while alive so let's try now that he's wormfood.

Must be having my manperiod, thanks for reading, burn my karma if you wish, carry on.

Some more info (4, Interesting)

photonic (584757) | more than 5 years ago | (#27069285)

I don't know the fine details of Weber's experiments, but I believe his 2 meter metal bar [wikipedia.org] was operating at room temperature, so he was severely limited by thermal noise. His claimed strain sensitivity (delta L / L) was on the order of 1e-16. There are currently a small number of resonant bars operational which are kept at just a few Kelvin. They reach a sensitivity around 1e-21 in a narrow band and have not measured anything during the last ~5 years, so Weber's claim is highly unlikely. I am involved with one of the big [caltech.edu] interferometric [ego-gw.it] detectors [aei.mpg.de] , which use vacuum tubes of several kilometers and reach sensitivities at the 1e-22 level over a broad bandwidth. If the astrophysical models are right we should be able to detect something within the next 5 years.

As already mentioned in a previous comment, the article is somewhat speculative and it is a little bit late to verify the experiment. The standard accepted practice for claiming the detection of a GW is to observe the event with at least 2 detectors which are separated far enough to not measure the same external disturbances (but preferably 3 or more spread around the world so that you can do proper triangulation of the source). One single glitch might be a cosmic ray, lightning, dust falling before your detector, an earthquake, an instrumental error, anything. We see more of those than we like. One glitch measured at different observatories within the time it takes to travel at lightspeed (a few ms) at different observatories around the world might give you a nobel prize.

One book that is high on my 'to read' list is Gravity's shadow [amazon.com] , which supposedly describes not only Weber's experiments, but also its reception by the scientific community and the eventual downfall of Weber's reputation.

I didnt "observe" them... (1, Offtopic)

alexborges (313924) | more than 5 years ago | (#27069737)

I was in very very very "high" school and got to SURFem!

Anonymous Coward (0)

Anonymous Coward | more than 5 years ago | (#27069905)

The paper is 5 pages long, with hardly any equations in it - there is no calculation of anything; just a big hand-wavy argument.

I'm not saying the guy is wrong, but he needs to do a hell of a lot better than this. Note that this is a pre-print and has not been published anywhere yet.

In the reference list he cites a guy called Preparata who was touting his "superradiance" theory in 1990 which would dramatically increase the sensitivity of gravitational detectors - no one bought it then, though the experimenters gave him a serious hearing.

In homage to this audience, may I suggest that he goes away and does a proper calculation ... on a beowulf cluster running linux! yay MS sux l44t h4xors rule !!

Light Speed (0)

Anonymous Coward | more than 5 years ago | (#27070297)

It's the same as the people who believe you can't travel faster than light. Those that rely on old models, who can't see ahead of their own 2 feet. Those that believe they have learned enough are fools. They are mad that they aren't smart enough and as a result can't take credit. They can't think of their own theories. They think by tearing down someone else they make themselves bigger. These are the people that make discoveries through government legislation. "See how smart I am!", they proclaim. In reality they are only proving the other man.

See you in the past!

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