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Initial Tests Fail To Find Gravitational Waves
eldavojohn writes that though gravitational waves are "predicted to exist by Einstein's Theory of General Relativity, the initial tests run by the Laser Interferometer Gravitational-Wave Observatory Scientific Collaboration (LIGO) failed to find anything. It doesn't disprove their existence although it does rule out a subset of string theory. From the article, 'For example, some models predict the existence of cosmic strings, which are loops in space-time that may have formed in the early universe and gotten stretched to large scales along with the expansion of the universe. These objects are thought to produce bursts of gravitational waves as they oscillate. Since no large-amplitude gravitational waves were found, cosmic strings, if they exist at all, must be smaller than some models predict.' The scientists working in Washington and Louisiana (in tandem to rule out flukes) will now move on to Advanced LIGO which will analyze a volume of space 1,000 times larger. If they don't find any gravitational waves in that experiment, the results will be more than unsettling to many theorists."
Have they tried turning it off & back on again?
Meta will eat itself
That's how science works, yeah.
As far as I remember from my course on general relativity, gravitational waves follow from a linearization of Einstein's field equations. Thus, if they failed to find them, it wouldn't falsify the theory as a whole but only the linear approach to the field equations.
Gravity sucks.
"The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
An experiment is only a failure if you don't learn anything from it.
Doesn't mean the gravitational waves aren't there.
Maybe they've just got the detection method wrong.
+++ Divide By Cucumber Error. Please Reinstall Universe And Reboot +++
Meta will eat itself
Will these tests apply for open, closed, or both so far as strings are concerned? IIRC, open and closed string models are mutually exclusive and should each have a different 'signature' that could be tested for.
If I mod you up, it doesn't necessarily mean I agree with what you've said, sorry.
It should be noted that the existance of gravitational waves is pretty much certain - measurements of pulsars like the Hulse-Taylor binary match up perfectly with the predictions of GR.
What LIGO is about is trying to observe them directly, rather than just observing the effects of them.
This is obviously because gravity does not exist, but the observed effect is a result of an higher intelligence pushing things down.
http://www.theonion.com/content/node/39512
> The worst, that could happen for a physicist, would be that the observations could be explained with GR.
This kind of (extremely common) remarks strike me as frivolous. It is one thing to say that physicists enjoy being disproved, because this shows the length of the road ahead; it is another thing to say that physicists would hate to attain knowledge in one particular area or other. Science is in the business of securing truths, not in the business of idly advancing ever-refutable theories.
More like a cycle... observe, theorise, observe to check results, refine theory.
In this case, this is exactly what's happened - the observations looks like they may not fit the theory perfectly - hence, once that's been double-checked, go back and revise the theory and try to find out why.
If you don't test the theory, it's worthless. And if you posit a theory, only observation will definitively "prove" it. Science is about positing theories, observing results, and if they fit the theory - WONDERFUL... you just "predicted" part of the universe that nobody has before.
Unless horses get so expensive and building carts so cheap you'd rather prepare a thouosand different carts just to be absolutely sure of which kind of horse you're going to invest all your effort trying to find.
Not really. String theory is based on observations like any theory. You can observe things, see that it lines up with your theory, and you can falsify string theory. The problem with string theory, and the reason why people complain about it, is that most of its observations are also true of the boring old theories we have right now or true of other variations of string theory. People get a little annoyed when you come up with a dozen contradictory string theories and according to all known observations they could all be true and no one can figure out a way to disprove any of them shorting of lighting off a big bang.
Intelligent Design has theories? What, if anything, does it predict? How could it be falsified?
This is like that Babbage quote: I am not able rightly to comprehend the kind of confusion of ideas that could provoke such a question.
Those who advocate genocide deserve every protection afforded by law, and none afforded by common human decency.
Thats half-way there. Observe, then theorise, then make a prediction, and test that. The problem is that we have General Relativity and Quantum Mechanics, and both describe their own domains very well (the very large and very small, respectively) - but we have no way of combining the two into a single, unified theory.
String theory in its various permutations could be (partial) theoretical solutions to this, but coming up with testable predictions of such theories (such as large-amplitude gravitational waves) is horrendously tricky. Indeed, some theories are pretty much untestable by definition - many string theories have been considered to come into this category.
So we have our observation (GR and QM both work well, but are hard to unify), we have many predictions (string theories, etc), and now we have a test of many such theories in the form of this experiment.
"Observe then theorise" is all well and good, but when you can't you can test predictions of your theory, its not worth much.
Whilst scientists, being human, sometimes form attachments to a particular theory, the failure to find predicted gravity waves can only possibly be good for physics. It is also an exciting time for physicists; failures of existing theories to explain observations provide the kind of mystery a scientist can make a name for himself or herself by solving.
If we can put a man on the moon, why can't we shoot people for Apollo-related non-sequiturs?
That's apprehend
Languages aren't inherently fast -- implementations are efficient
We know that pulsars conserve energy because they keep turning their lights off!
Now maybe the string theorists, such as Michio Kaku, will spend a little more time back at the drawing board and a little less time pretending to be Carl Sagan crossed with Alan Alda.
I doubt it. There is no such thing as "String theory". It should be more accurately called "String Theories". It's like a multi-headed hydra that lives forever. Falsify one part of it and 3 other theories pop up to replace it.
The only thing that can really kill String Theories is a experimentally verified competing theory that's unifies quantum mechanics and general relativity. Kill the body and the head will die.
AccountKiller
I like to see string theory crumbling as much as the next man, but err.. that :
dark matter can be explained by the evolution of advanced technological civilizations based on *known* physics (through molecular nanotechnology and extreme engineering)
If given the choice between these two propositions, I think I'll stick with string theory and its 26+ space dimensions. But kudos to you for pioneering a new approach to astrophysics that consists in claiming "space aliens did it".
You just got troll'd!
Intelligent Design has theories? What, if anything, does it predict?
That is actually the wrong criticism of ID. ID can certainly predict things. If the 'designers' are a bunch of bored aliens that like to do anal probes, you could predict that the aliens will cause changes in animals DNA such that they tend towards having ass holes. If the FSM is the designer, than you will predict that creatures will be designed towards higher spaghetti creating lifeforms. If the designer is an all powerful omnipotent god that thinks beetles totally kick ass, you will predict that there will be a crap ton of beetles (which there in fact are).
And hey, all of the above might very well be true.
If someone wants to go out and try and prove it, more power to them. The issue is that ID is nothing more than an attempt by religious nuts to try and teach about baby Jesus in the schools. If there were people that were taking the 'study' of ID seriously, they would sit around designing experiments to catch whatever the mysterious force is that manipulates DNA to force evolution and create their spiffy designed universe. Further, when they pondered what the force was, they would have to constrain themselves to theories based upon real physics. This would handily rule out 'magic' and 'god juice'. If they want to show that the force is god juice, they then need to go ahead and reinvent physics to try and explain how the force of god juice works. At no point does 'magic', 'just cause', or 'humans can't understand because they are not Jesus' acceptable.
The issue with ID is that science doesn't accept 'magic' as an answer. If you say a designer is forcing evolution, you need to go and figure out the force being used, and it either needs to conform to current theories or you need to find new ones that explain all observable events. This is what makes the ID folks nothing more than religious whack jobs. When Darwin declare that natural selection was the answer, people went to work figuring out how natural selection works and didn't just decide it was a magical force that just happens. They tore it apart by from a macroscopic level that studied how animals compete and co-opt, they tore it apart on the biological level understanding how cells reproduces, and they keep on drilling down until they are looking at atoms and figuring out how quantum affects influence evolution. At no point was anyone ever satisfied with 'magic' as the answer.
Why 17 years after "Nanosystems" was published do we still not have an complete atomic level design for a molecular nanoassembler?
Patience, young grasshopper. Game of Life rules published in Martin Gardners column in October 1970, first turing machine in GoL that I'm aware of, April 2000. Wait at least another 13 years or so.
http://en.wikipedia.org/wiki/Conway's_Game_of_Life#cite_note-0
http://www.rendell-attic.org/gol/tm.htm
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
You just said what he said, but he used the language of science while you used the language of bonghits-in-a-dorm-at-a-good-college.
No, no...I was confused at his post too (wow this guy reads too much SF!) but then I realized that his first statement is not about the existence of advanced civilisations, but rather suggests that an advanced civilisation will have more of the tools and ability to solve these problems. He is suggesting that WE need to focus on such efforts as nanotechnology and such, because once we're one of those `high tech civilisations', doing physics will be easier. To an extent I think he's got a point; we can certainly do much better physics now than Gallileo (if only because of apparati), and nanotechnology may indeed allow us to build larger (or smaller) and more stable structures, which may be necessary to directly detect some of the more elusive universal secrets.
Please see the LISA mission:
http://lisa.nasa.gov/
LISA can be thought of as a giant Michelson interferometer in space. The spacecraft separation sets the range of GW frequencies LISA can observe (from 0.03 milliHertz to above 0.1 Hertz).
-- I was raised on the command line, bitch
If you talk to a string theorist, it feels like you are talking to a religious person.
-- I was raised on the command line, bitch
My own "pet theory" for this was that they would never be detected because although they do exist, they perturb the measurement device to the same degree that they do everything else, ie a gravity wave may perturb one arm of a LIGO detector, but it also correspondingly perturbs the waves of the laser beam passing through it. As a result it isn't detected.
An analogy: It would be like measuring everything in a room with a ruler, then scaling the whole room including the ruler up or down. You wouldn't see a change with the same scaled ruler; you'd have to bring one in from outside.
I bounced this idea off a few physicists (including Bruce Allen who runs the Einstein@Home project on LIGO) but they don't seem to like it. :^) Maybe it will turn out to be correct, who knows. It certainly seems to be turning out to be more difficult to detect gravity waves than was initially predicted.
-- Insert witty one-liner here. --
Since when do ID people look at evidence? In the Pennsy ID trial the ID proponents admitted to not running any of the experiments they proposed. Yes, in science when a theory doesn't fit the evidence you either adjust it or throw it out. For example, experiments looking for the ether led to the dismissal of both the particle and wave theories of light. They gave way to the theory of relativity which is still being rigorously tested because scientists don't take anything for granted.
Compare that with dogmatic writings that get promoted as absolute unchanging truth in spite of being full of internal contradictions as well contradictions with history and with science.
I proposed the "really tiny strings" theory long ago that said that a really tiny string is attached between the gravitational bodies like the earth and the moon. Sure, some laughed and countered with their silly "spooling paradox" argument, but sometimes it takes decades to appreciate a true genius.
I swear to God...I swear to God! That is NOT how you treat your human!
ID it not a theory, it is a religious/political ideology being presented as a theory that aims to explain the perceived weaknesses of science in order to advance the interests of certain groups and individuals.
- This beautiful, complex interaction could not have possibly arisen spontaneously, therefore God's will.
- This makes no apparent sense/has no apparent purpose, therefore descent from God's will.
- You cannot explain something neatly, therefore God's will or the descent from it.
That's not a theory. The aim of a theory is to predict something that you can then test for. ID doesn't predict anything, there is no empirical test for God and deciding arbitrarily whether things are as God intended or not does not increase our understanding of them - it's merely a reactionary attitude advanced by old men who are afraid of change and what it means for their status.
Besides, even if you believe in God the creator, the ID advocacy of ignorance still seems bogus; God gave you all these wonderful cognitive capabilities, so why not use them to try to fully appreciate his grand work? You would be wasting God's gifts if you didn't. :p
Even as you read this, your pants are strangling your loins! Aaa!
Yep. OK, enough with ID vs evolution, let's move on to the other battlefront of the science vs faith war. Climate change!
Global warming, schmobal schmwarming! Temperatures have gone done for the last 10 years (facts here [wikipedia.org]), so everything is just fine, it's just evil liberals who hate our benevolent oil companies because they're in the pocket of Big Ethanol. Discuss.
You just got troll'd!
You *are* aware that Dark Matter has been observed, right? Or did you just miss the announcement of the Bullet Cluster results (among others)? As for Dark Energy, that isn't really a theory, so much as an observation with no explanation. Specifically, the rate of expansion of the universe is increasing. This is a fact. *Why*, we don't know, so we just call it Dark Energy for now. It's a placeholder, nothing more.
So please, take your trolls and go back into your basement, as it's pretty clear you don't really know what you're talking about.
Hey, I'm having a party tonight and I want to make sure it wraps up by 1 o'clock. Could you stop by at about 12:55 and bore everyone out of the place for me?
. Science is in the business of securing truths, not in the business of idly advancing ever-refutable theories.
I'm sorry, science is in the business of proving theories wrong. All current scientific theories are merely those that have yet to be proved wrong. They are extremely valuable in that they can be used to predict future behavior of the universe to a significant degree of confidence. However, scientific theories cannot be proven true, they can only be proven false.
The great weakness of science is that people have a tendency to view theories that have been around for a long time and not proven false to be true. All it really means is that they are reliable predictors of the behavior of the universe insofar as our technology allows us to observer the behavior of the universe. Sometimes this means that they are good theories that are very useful (say General Relativity), other times it merely means that our technology has not yet reached the point where we can reliably test any of the theory's predictions (say the various String Theories).
The truth is that all men having power ought to be mistrusted. James Madison
That is actually the wrong criticism of ID. ID can certainly predict things.
Quite correct, that is the wrong criticism. Unfortunately, yours is, too. The argument that "science doesn't accept 'magic' as an answer", and therefore ID isn't science is a circular one. ie, if ID is magic, then science doesn't accept magic, therefore ID isn't science. Well, yeah, duh, no kidding. Heck, technically, I think that might actually be "begging the question".
No, the *real* problem with ID is that it isn't *falsifiable*. And this is specifically because any attempt to falsify the theory, by providing evidence which contradicts any "predictions", could easily be reinterpreted under the lens of "god did that, too". And if a theory can't be falsified, it simply isn't science.
How does *failing* to find the thing which was predicted to exist by Einstein, prove Einstein right? Granted, they weren't *expecting* to see gravitational waves at this point, because they were only looking for waves which would have been at such a high magnitude that they weren't expected to exist *except by string theorists* because of part of string theory. So, that part of string theory was *dis-proved*, but Einstein's theory has not yet been proved correct (though they expect it will be 'soon' when they start looking for smaller magnitude waves).
Anyhow, what's wrong with proving that our ideas about the natural universe are either correct or incorrect (or somewhere in between, in some cases)? You know, one never knows all the applications of scientific knowledge until long after that knowledge is obtained. Perhaps spending all this money now to do this science today, will lay the groundwork for very useful applications in the future? Perhaps the knowledge gained from these observatories will help us figure out how to make fusion work economically, or help us develop more advanced spacecraft, or even more advanced terrestrial vehicles? Or help us detect the aliens which are spying on us with advanced cloaking devices but can't hide their G-waves (ok, that last is mostly a joke, but one never knows)?
Scientific knowledge is, in itself, largely useful - how much has our technology and economy, our health and standard of living, improved, because of scientific advances achieved in past centuries that are only now being put to great use?
Well played sir. I'd mod you funny but I'm a little pissed off about the coffee dribbling down my screen.
In a field of grain, you can grow wheat, barley, rye or oats. It's still a field. ID is still an area that people study. It's a field. You may not agree with it. I may or may not agree with things that come out of it. That's fine. It's still a field of study. Get over it.
sudo mount --milk --sugar
In a field of grain, you can grow wheat, barley, rye or oats.
That's very true, of course. But you can't grow wheat, barley, and Ford Pintos. I'm arguing that physics, philosophy, and automobile repair are fields of study, while ID is not. It is a platform. An agenda. It's like saying the people paid by the tobacco companies to falsify studies on the effects of tobacco smoke are conducting science. Apples to orangutans.
Disclaimer: I don't work on LIGO, but I work with people who do.
LIGO didn't expect to see a signal above the noise here. What it has done, is largely rule out a lot of 'exotic' sources - sources with equations of state that don't fit the normal matter we see, but some of the more ambitious parts of string theory thought might be possible. What they have achieved is a phenomenal reduction in their 'noise curve' - the background above which a signal must register to be considered real. So far it's only been a one-way test - just ruling out exotic sources, but nothing that we think should necessarily be there.
LIGO primer and vast oversimplification:
LIGO is an interferometer. The way it works is that a laser is split into two parts, each of which goes down an equal length tunnel, at right angles to one another. If the light went the same distance, when it is reflected back, it should still be in phase, and should interfere constructively (think back to intro physics and the way waves on a string add). If a gravitational wave which had the right polarization passed through the region in the time of detection, one tunnel will have been 'shorter' due to the contracting geometry caused by the wave, and hence the beams will no longer be in phase when they return, so will not interfere constructively in the same way.
So why is it so hard to see waves? Well, all kinds of things (drilling, trucks going by, someone sneezing!) can cause a minute wobbling of any part of the equipment and thus will cause the waves to interfere in the wrong way. What LIGO looks for is a specific 'signature' measured at three sites concurrently, the signature being the waves predicted to occur from certain galactic events (two black holes spiraling into one another, for example). They do some pretty impressive data processing to look for this, but so far have only found that they can't see anything above the noise. We've ruled out some of the less likely things that could be going on - types of matter that some string theories allow, but certainly aren't predicted to exist by established theories (like GR).
However, over time with a few additions to 'advanced' LIGO, or the amazing LISA project we should have a two-way test: Either we'll see the wave that GR predicts to exist from standard black hole collisions, or theoretical physicists have a lot of explaining to do.
Here you have just given away that you start with the philosophical assumption of naturalism: that is, everything that is (or everything that affects the universe) happens inside the universe. There is not, cannot be, any supernatural. That's not a proof you have, it's an assumption that you start with. And that's fine, we all make assumptions (e.g., logic works), but it's better if you're honest about it.
Let's try an analogy. Computers operate by rules, right? Everything in the computer can be defined by the state of its memory, registers, and disk (toss in whatever extra motherboard or micro-architectural state you want). How it transitions from one state to another depends only on what the state before it was, and any inputs into the system. The vast majority of those state transitions are 100% deterministic. (I know, I did my PhD thesis on this stuff.) Only a relatively small amount of input when you boot up determines whether you're playing Quake with friends or writing posts on Slashdot. In fact, for a running system overall, the less input needed to make the whole run smoothly the better designed it was.
Now, suppose there were a self-aware program living in your computer, looking at the state of the system, and trying to determine if there were such things as these mysterious "users", and if so, how they affected the state of the system. All you know is "data"; you can't see the physical world. Since these mysterious "users" don't live in data, to you they're essentially super-natural. Now ask your question: How is it that these "users" affect data?
If you do, you'll see that in this case "magic" (meaning, "something not described in the rules of the system") is an acceptable answer; in fact, "magic" is by definition the only answer. Users create the input from the keyboard, mouse, network, &c that feed into the system. Users really can decide which processes live and die; but what does that look like to a program? Some random data came in on a certain line which fed into a program, which when certain data hits inside a certain area on the screen (the "X" button on the upper right-hand-side of a window), the program sends a signal to another program which sends a signal to another program which tells it to exit. An atheist program might say those inputs were random, like states in quantum physics. Furthermore, really technical humans may have even more control: They can use in-circuit-emulators to directly change state on the CPU and use PCI bus devices hidden from the cpu to directly read and write memory. They can rewrite the register after an ADD instruction to make it look like it added 2 and 2 and got 5.
People who believe in the Judeo-Christian God believes that God has that kind of access to the universe. If he can feed 5000 people from five loaves of bread and 2 fishes, turn water into wine, and come back from the dead, surely he can twiddle some DNA at key points in history. By definition, a "miracle" is a temporary suspension or contravention of the normal laws of the universe. And thus, by definition, the "force being used" may not be detectable or describable under the laws of physics, any more than changes a programmer makes using an in-circuit-emulator would be detectable or describable by a program inside the computer trying to determine if the universe consisted only of data, or if there was a "supernatural" outside of the data.
Note that my point is not to defend any particular ID theories or people who promote them. I have a lot of biologist friends who are Christians, and think that the evidence pretty clearly supports the current scientific understanding of the development of life here on Earth. Believing that God can intervene in the natural world doesn't mean that you can't believe in and shouldn't look for natural laws and natural explanations for things. But your logic of "ID is bad because it will accept a supernatural explanation (i.e., magic)" isn't sound.
TCP: Why the Internet is full of SYN.
Science studies that which is not "magic". A supernatural explanation may be true and it would still not be science. This is a necessary limit of science.
However, even if the answer is "God did it", if God chooses to do things according to some set of rules (as most religions would have us believe), then those rules should be apparant from the patterns observable in the universe, and science should be able to deduce those rules.
That is the point of science: to observe the patterns than events in our universe follow, and produce a set of rules -- a predictive model -- that explain those patterns. This approach only fails if there are effects in our observable universe with an arbitrary or random cause outside of it. Only a God who actually behaved in an arbitrary and random way would affect the predictive success of scientific models.
Socialism: a lie told by totalitarians and believed by fools.
That isn't a valid argument. You could say the same thing about any subject. Such as:
At many levels, Mathematics is an agenda as well. Why else would there be such a push to have it taught in schools?
The simple answer is because evolutionism is actually based on scientific evidence. ID is simply a religion that is trying to make itself look scientific so it can be lobbied to be taught in public schools.
If ID is magic, then it's not science, therefore ID is magic. :)
Now this is a perfect example of begging the question -- you assume the thing you want to prove as a premise in your argument.
Thought thinks itself.
A statistical test akin to testing for a biased coin would be sufficient to create an ID test.
So then do it. Create the test and give us the results, let us verify your test methodology and your data and your results. Until such a time, ID is merely conjecture and not a scientific hypothesis.
You invent experiments to PROOF you theory, not to falsify it.
Sorry, no, that's just wrong. You *can't* prove *any* theory, as there may always be some case that the theory gets wrong. This would be why no modern theory, no matter how well it's predictions match experimental result, has ever been promoted to a law (see General Relativity for an excellent example).
The purpose of experiment, then, is to test the theory and see if reality matches it. If it doesn't, the theory is falsified and you go back to the drawing board, either by revising the theory or positing an entirely new one. If, however, reality does match the prediction, you go on to the next experiment, once again seeing if you can falsify the theory with the next result.
Contrast this with Intelligent Design. ID can certainly posit certain predictions (eg, irreducible complexity of the eye). And you can certainly try to falsify it ("See, look, here are the chain of fossils that show the evolution of the eye"). But an ID proponent can simply declare that God made it that way, and then move on to the next prediction. IOW, the theory is impossible to falsify, as it always gives the believer an "out".