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General relativity survives gruelling pulsar test -- Einstein at least 99.95% right
EurekAlert (AAAS) ^ | 13 September 2006 | Staff

Posted on 09/13/2006 10:57:52 AM PDT by PatrickHenry

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To: El Gato

Cool beans. :-)


61 posted on 09/13/2006 1:28:41 PM PDT by RadioAstronomer (Senior member of Darwin Central)
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To: Moonman62

Will be an exciting day. :-)


62 posted on 09/13/2006 1:29:33 PM PDT by RadioAstronomer (Senior member of Darwin Central)
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To: calex59
Some people have no sense of humor. Are you one of them?

In general, no. But humor doesn't come through very well sometimes. It's often hard to tell the difference between a joke and simple ignorance. So I assume people are being serious. Since you apparently weren't, I retract the statement.

63 posted on 09/13/2006 1:30:57 PM PDT by El Gato
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To: Blind Eye Jones
Yes, but he is definitely wrong on the remaining 0.5%.

It is close to 90 millionths of a second and the ratio of the observed and predicted values is 1.0001 +/- 0.0005 - a precision of 0.05%.

Did you mean the other 0.05%? The headline is misleading. Apparently the observed values were dispersed because of measurement of error. Some percentage (68%, 95%?) were in the range of between 0.9996 and 1.0006 of the theoretical value.

The situation is a little complicated, but for the sake of argument, say that Einstein perdicted 100 microseconds of Shapiro delay. The experiment is repeated once every 2.4 hours for three years. The average delay is 100.01, with values dispersed above and below. If the population is normally distributed with a standard deviation of 0.05 microseconds, we would say that ratio of measured to expected was 1.0001 +/- 0.0005. Not bad really. It doesn't mean that Einstein got .05% wrong, only that if he was wrong the experiment did not have enough sensitivity to detect the error.

The above was greatly simplified for the purposes of illustration, of course. In the first place, the delay can probably measured with enormous accuracy, much better than a nansecond. The uncertainty surely lies in the estimates of GR model parameters, that is in the application of the theory. The uncertainty isn't in the measured delay, but in figuring out what GR predicts.

If you're interested you can read Shapiro's own original treatment in Radar Astronomy, Evans and Hagfors (Editors), McGraw-Hill, 1968. Shapiro wrote chapter 3, see especially 3-2B, "Effects of General Relativity". A cracking good yarn!

64 posted on 09/13/2006 1:36:01 PM PDT by Lonesome in Massachussets (NYT Headline: 'Protocols of the Learned Elders of CBS: Fake But Accurate, Experts Say.')
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To: El Gato

I put a smile sign at the end of my comment so humorless people could tell I was kidding. I guess I will have to do something else in the future, maybe spell out in big words "i AM JOKING".


65 posted on 09/13/2006 1:36:52 PM PDT by calex59 (Hillary Clinton is dumber than a one eyed monkey with a brain tumor(credit to Harley69))
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To: KarlInOhio
...whenever you think of cutting edge astronomy.

I believe it's in a very limited, if not banned area for any and all broadcasting. In other words, it's
a pretty quiet place in terms of man-made transmissions.

IIRC, it started out as an NSA site, and as technology advanced, the NSA no longer needed it, and it transitioned to radioastronomy along the way.

I think at one point, the land was supposed to be traded with somebody, and that's when Byrd seized the
opportunity to have yet another thing named after himself, using public funds.

66 posted on 09/13/2006 1:48:35 PM PDT by Calvin Locke
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To: HeartlandOfAmerica
since it contributed to the federal deficit, maybe we should call it the Robert C. Byrd Federal Deficit as well :)

ROTFL! Hey, he wants his name to live forever, doesn't he?

67 posted on 09/13/2006 1:58:35 PM PDT by jennyp (There's ALWAYS time for jibber jabber!)
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To: PatrickHenry

The first observational evidence for gravity waves.

This is an historic occasion!

I'll always remember where I was when I saw the first reports of evidence for gravity waves.

I still remember where I was when I heard that the Z particle had been discovered. I was sitting at home and had just opened a fresh bag of Doritos...


68 posted on 09/13/2006 2:01:20 PM PDT by <1/1,000,000th%
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To: PatrickHenry

So, does this impact the hypothesis that there's an aspect of gravity that only shows up at very large distances, or is 2000 light-years still too close and/or 0.05% error bars too big to say?


69 posted on 09/13/2006 2:05:17 PM PDT by jennyp (There's ALWAYS time for jibber jabber!)
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To: jennyp

I don't think that's part of this. But I'll let the smart guys give their more worthy opinions.


70 posted on 09/13/2006 2:12:41 PM PDT by PatrickHenry (Where are the anachronistic fossils? Where are the moderate creationists?)
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To: Red Badger

You mean they haven't? I couldn't tell when I was driving the Robert C. Byrd memorial highway (I-77) or stopping at the Robert C. Byrd memorial rest areas...

In all seriousness, a churchmate of mine in Michigan is a steelworker and worked on the construction of that telescope. Big honkin' sucker.


71 posted on 09/13/2006 3:58:47 PM PDT by MikeD (We live in a world where babies are like velveteen rabbits that only become real if they are loved.)
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To: El Gato
Gravitation and cosmology

There are quite a few copies on the used market, many under $50.00.

See Bookfinder.com.

One is as low as $16.99.

72 posted on 09/13/2006 4:12:21 PM PDT by Coyoteman (I love the sound of beta decay in the morning!)
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To: jennyp
ROTFL! Hey, he wants his name to live forever, doesn't he?

*laugh* Yah. President Reagan once said that a tax is the nearest thing to immortality in the fed govt. I think that a deficit is really close though :)

I figure the Congress will get the deficit under control about the day after the universe ends.

73 posted on 09/13/2006 4:45:14 PM PDT by HeartlandOfAmerica ('... we want the human rights officers, we want the Americans to come back' - Abu Ghraib Prisoner)
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To: jennyp
So, does this impact the hypothesis that there's an aspect of gravity that only shows up at very large distances,

Actually, my first thought was, "So there ARE gravity waves! If we can find em, we can control 'em!" As in anti-gravity :)

74 posted on 09/13/2006 4:47:37 PM PDT by HeartlandOfAmerica ('... we want the human rights officers, we want the Americans to come back' - Abu Ghraib Prisoner)
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To: tallhappy
This is an excellent example of the different nature between physical sicence and theories and biolgical science and theories. There are no comparable theories in biology to test so rigourously.

No theory in science (physics, chemistry, biology, or any other) is ever proven. All a scientist can do is collect experimental data. If the experimental data is close to what the theory predicts, you can say that the data supports the theory (or hypothesis). This is inductive reasoning, not a proof.

This is a point of confusion in most people who are not scientists. Unfortunately, scientists do not help to clarify how they work. I suppose they want people to think they are right, and that is supposed to end any arguments.

75 posted on 09/13/2006 5:06:57 PM PDT by stripes1776
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To: stripes1776
scientists do not help to clarify how they work.

Some do take the trouble, usually after they have done their major work in their discipline. There are plenty of books available already that explain how it works and what the limitations are. Michael Polanyi was particularly good at this.

76 posted on 09/13/2006 5:11:03 PM PDT by RightWhale (Repeal the law of the excluded middle)
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To: RightWhale
Some do take the trouble...

Yes, you are right. Some scientist do take the trouble to explain how science works. But how many write for the general public rather than for their fellow specialists? I would say not a lot.

A large part of the problem is also journalists who don't take the time to explain things adequately in a news story. There is some experiment and the headline becomes: "Scientists Prove XYZ Theory."

77 posted on 09/13/2006 5:22:50 PM PDT by stripes1776
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To: stripes1776; RightWhale
Some do take the trouble...

Yes, you are right. Some scientist do take the trouble to explain how science works. But how many write for the general public rather than for their fellow specialists? I would say not a lot.

A large part of the problem is also journalists who don't take the time to explain things adequately in a news story. There is some experiment and the headline becomes: "Scientists Prove XYZ Theory."

And then there the science-deniers who will not believe anything that goes against their preconceived ideas, no matter how well documented. We see a lot of this lately from some creationists, although there still a few geocentrists and flat-earthers still around.

78 posted on 09/13/2006 5:32:31 PM PDT by Coyoteman (I love the sound of beta decay in the morning!)
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To: RadioAstronomer
Evidence of gravity waves placemarker.

Speaking of which, has anyone started a suicide watch for a certain Freeper who shall remain nameless?

79 posted on 09/13/2006 5:34:46 PM PDT by longshadow (FReeper #405, entering his ninth year of ignoring nitwits, nutcases, and recycled newbies)
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To: longshadow

Or removed any rope-like material from the belfry?


80 posted on 09/13/2006 5:35:56 PM PDT by js1138 (Well I say there are some things we don't want to know! Important things!")
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