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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.
Gravity sucks.
It always lets us down
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.
An experiment is only a failure if you don't learn anything from it.
There are still degrees of success.
I tend to consider it a failure if all I learned is: "I should wear fireproof clothes for all my pyrotechnical flamabilities experiments.
Especially after the third time I learn the same lesson.
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.
Any experiment that doesn't result in a large explosion is a failure.
No, there are exact gravitational radiation solutions, and you can also predict gravitational radiation from weak-field situations where the linearized approximation is very, very accurano te (the h^2 term would be less than 10^-15 for the sun's gravitational field at Earth's orbit, for example). The decay of orbits due to gravitational radiation has been observed indirectly in PSR B1913+16, and matches the theoretical prediction. If no gravitational radiation is observed at the expected amplitudes for things like that, it will throw a lot more than just string theory into question, and would raise the obvious conservation of energy question about that pulsar.
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.
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!
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?
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.
Well, it's easy to explain: It conveys the wrong message. While the curvature of space is indeed similar to the curvature of a rubber hose when a mass is on it, the image you get is wrong at quite a lot of counts:
I hope those explanations did help a bit.
The Tao of math: The numbers you can count are not the real numbers.