| Topic: |
Science > Physics |
| User: |
"Sam Wormley" |
| Date: |
17 Apr 2007 12:08:11 AM |
| Object: |
Dragging on |
Dragging on
http://cosmicvariance.com/2007/04/15/dragging-on/
The annual April meeting of the American Physical Society is
currently underway. This meeting brings together thousands of
physicists, from all branches except condensed matter. The condensed
matter types have their own meeting (in March), which dwarfs ours.
For the next few days, there will be a flurry of press releases
originating in Jacksonville, Florida. Although I have been missing
the action down south, there is one press release which was
conspicuous in its absence. A measurement of frame dragging was not
announced by the Gravity Probe B satellite (affectionately known as
GP-B), as originally planned. Instead, NASA issued an Interim Report
summarizing the state of the data analysis thus far. The press
release is here.
See:http://cosmicvariance.com/2007/04/15/dragging-on/
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| User: "Daniel G. Emilio" |
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| Title: Re: Dragging on |
17 Apr 2007 07:47:41 PM |
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On Apr 16, 10:08 pm, Sam Wormley <sworml...@mchsi.com> wrote:
Dragging on
http://cosmicvariance.com/2007/04/15/dragging-on/
<snip> Although I have been missing
the action down south, there is one press release which was
conspicuous in its absence. A measurement of frame dragging was not
announced by the Gravity Probe B satellite (affectionately known as
GP-B), as originally planned. Instead, NASA issued an Interim Report
summarizing the state of the data analysis thus far. <snip>
It seems to me there are two possibilities.
The first possibility is that frame dragging was detected but there
was a large error and they needed additional time to clean it up. (If
detected with only small error, they would never be funded for the
extension to December considering how much this experiment has already
cost. Further, if that was the case then wouldn't they also not have
announced the results of the geodetic effect). But if they detected
frame dragging at all, then why not announce that fact. There would
be nothing to lose.
The second possibility is that frame dragging was not detected in any
amount. If that was the case, then their silence regarding any result
is totally understandable. They would need, and would get, extra time
and funding to eliminate all possibility that extraneous factors
contributed to the null result and they would never make such an
announcement of null result until after they did everything they could
to confirm it.
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| User: "" |
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| Title: Re: Dragging on |
19 Apr 2007 05:20:06 PM |
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Daniel G. Emilio <dgelaw@gmail.com> wrote:
On Apr 16, 10:08 pm, Sam Wormley <sworml...@mchsi.com> wrote:
Dragging on
http://cosmicvariance.com/2007/04/15/dragging-on/
<snip> Although I have been missing
the action down south, there is one press release which was
conspicuous in its absence. A measurement of frame dragging was not
announced by the Gravity Probe B satellite (affectionately known as
GP-B), as originally planned. Instead, NASA issued an Interim Report
summarizing the state of the data analysis thus far. <snip>
It seems to me there are two possibilities.
The first possibility is that frame dragging was detected but there
was a large error and they needed additional time to clean it up. (If
detected with only small error, they would never be funded for the
extension to December considering how much this experiment has already
cost. Further, if that was the case then wouldn't they also not have
announced the results of the geodetic effect). But if they detected
frame dragging at all, then why not announce that fact. There would
be nothing to lose.
The second possibility is that frame dragging was not detected in any
amount. If that was the case, then their silence regarding any result
is totally understandable. They would need, and would get, extra time
and funding to eliminate all possibility that extraneous factors
contributed to the null result and they would never make such an
announcement of null result until after they did everything they could
to confirm it.
The third possibility -- which is what is really happening -- is that
they won't know whether frame dragging was observed, and if so, how much,
until they understand their systematic errors better. In particular,
the experiment has four independent gyros, which are observed separately.
At the moment, the differences among the gyros is larger than the predicted
amount of frame-dragging. So, being good scientists, the GP-B people are
not yet prepared to make a claim one way or the other.
According to the people I've talked to, there is a good chance that the
differences among the gyros can be understood, in part because the mission
had a long calibration run to see how the gyros responded to various external
perturbations. If the external torques can be modeled, the results should
be good enough to give a fairly good number for frame-dragging. If they
can't, the conclusion will be that the experiment simply wasn't accurate
enough to say.
Steve Carlip
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| User: "Daniel G. Emilio" |
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| Title: Re: Dragging on |
21 Apr 2007 08:40:57 PM |
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On Apr 19, 3:20 pm, wrote:
Daniel G. Emilio <dge...@gmail.com> wrote:
On Apr 16, 10:08 pm, Sam Wormley <sworml...@mchsi.com> wrote:
Dragging on
http://cosmicvariance.com/2007/04/15/dragging-on/
<snip> Although I have been missing
the action down south, there is one press release which was
conspicuous in its absence. A measurement of frame dragging was not
announced by theGravity Probe Bsatellite (affectionately known as
GP-B), as originally planned. Instead, NASA issued an Interim Report
summarizing the state of the data analysis thus far. <snip>
It seems to me there are two possibilities.
The first possibility is that frame dragging was detected but there
was a large error and they needed additional time to clean it up. (If
detected with only small error, they would never be funded for the
extension to December considering how much this experiment has already
cost. Further, if that was the case then wouldn't they also not have
announced the results of the geodetic effect). But if they detected
frame dragging at all, then why not announce that fact. There would
be nothing to lose.
The second possibility is that frame dragging was not detected in any
amount. If that was the case, then their silence regarding any result
is totally understandable. They would need, and would get, extra time
and funding to eliminate all possibility that extraneous factors
contributed to the null result and they would never make such an
announcement of null result until after they did everything they could
to confirm it.
The third possibility -- which is what is really happening -- is that
they won't know whether frame dragging was observed, and if so, how much,
until they understand their systematic errors better. In particular,
the experiment has four independent gyros, which are observed separately.
At the moment, the differences among the gyros is larger than the predicted
amount of frame-dragging. So, being good scientists, the GP-B people are
not yet prepared to make a claim one way or the other.
According to the people I've talked to, there is a good chance that the
differences among the gyros can be understood, in part because the mission
had a long calibration run to see how the gyros responded to various external
perturbations. If the external torques can be modeled, the results should
be good enough to give a fairly good number for frame-dragging. If they
can't, the conclusion will be that the experiment simply wasn't accurate
enough to say.
Steve Carlip- Hide quoted text -
- Show quoted text -
On the other hand, I suspect that even if they do understand the
differences in the gyros and yet still do not detect frame dragging
the results won't be accepted in any event. Maybe I'm wrong. But
after 100 years I doubt if any negative result would ever make any
difference. It reminds me of George Bush and the Iraq war. I believe
he will go to his grave believing that he only needed more time to
prove his approach was right. There's simply too much invested to
scrap current thinking. If frame dragging is detected by any amount
then case closed. But if it isn't detected by any amount then case
still closed - there would never be a repeat of this experiment.
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| User: "Ken S. Tucker" |
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| Title: Re: Dragging on |
22 Apr 2007 11:32:49 AM |
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On Apr 21, 6:40 pm, "Daniel G. Emilio" <dge...@gmail.com> wrote:
On Apr 19, 3:20 pm, wrote:
Daniel G. Emilio <dge...@gmail.com> wrote:
On Apr 16, 10:08 pm, Sam Wormley <sworml...@mchsi.com> wrote:
Dragging on
http://cosmicvariance.com/2007/04/15/dragging-on/
<snip> Although I have been missing
the action down south, there is one press release which was
conspicuous in its absence. A measurement of frame dragging was not
announced by theGravity Probe Bsatellite (affectionately known as
GP-B), as originally planned. Instead, NASA issued an Interim Report
summarizing the state of the data analysis thus far. <snip>
It seems to me there are two possibilities.
The first possibility is that frame dragging was detected but there
was a large error and they needed additional time to clean it up. (If
detected with only small error, they would never be funded for the
extension to December considering how much this experiment has already
cost. Further, if that was the case then wouldn't they also not have
announced the results of the geodetic effect). But if they detected
frame dragging at all, then why not announce that fact. There would
be nothing to lose.
The second possibility is that frame dragging was not detected in any
amount. If that was the case, then their silence regarding any result
is totally understandable. They would need, and would get, extra time
and funding to eliminate all possibility that extraneous factors
contributed to the null result and they would never make such an
announcement of null result until after they did everything they could
to confirm it.
The third possibility -- which is what is really happening -- is that
they won't know whether frame dragging was observed, and if so, how much,
until they understand their systematic errors better. In particular,
the experiment has four independent gyros, which are observed separately.
At the moment, the differences among the gyros is larger than the predicted
amount of frame-dragging. So, being good scientists, the GP-B people are
not yet prepared to make a claim one way or the other.
IIRC correctly each of those 4 gyro's was able
to measure the frame-dragging to 1%. Now it
sounds like the error bars are being pushed out
to 100%, (100x) because they didn't find it.
According to the people I've talked to, there is a good chance that the
differences among the gyros can be understood, in part because the mission
had a long calibration run to see how the gyros responded to various external
perturbations. If the external torques can be modeled, the results should
be good enough to give a fairly good number for frame-dragging. If they
can't, the conclusion will be that the experiment simply wasn't accurate
enough to say.
This sounds like the null result of the MMX,
if you can't find the ether, blame the equipment.
One way or the other, an equipment malfunction
occurred causing an error rate of 100x design
specification OR the frame-dragging effect is
100x less than theory predicted.
Since the geodetic effect banged in well, and no
previous report of 100x equipment design specification
error is indicated, the experiment proves there is
NO frame dragging.
It appears to be the case for LIGO too which is related.
Steve Carlip
On the other hand, I suspect that even if they do understand the
differences in the gyros and yet still do not detect frame dragging
the results won't be accepted in any event. Maybe I'm wrong. But
after 100 years I doubt if any negative result would ever make any
difference. There's simply too much invested to
scrap current thinking. If frame dragging is detected by any amount
then case closed. But if it isn't detected by any amount then case
still closed - there would never be a repeat of this experiment.
There may be other ways to do the experiment,
but I've seen calculations where it nulls out always,
IOW's it's a CS figment.
Ken S. Tucker
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| User: "" |
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| Title: Re: Dragging on |
23 Apr 2007 12:56:28 PM |
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Ken S. Tucker <dynamics@vianet.on.ca> wrote:
On Apr 21, 6:40 pm, "Daniel G. Emilio" <dge...@gmail.com> wrote:
On Apr 19, 3:20 pm, wrote:
[...]
The third possibility -- which is what is really happening --
is that they won't know whether frame dragging was observed,
and if so, how much, until they understand their systematic
errors better. In particular, the experiment has four
independent gyros, which are observed separately. At the
moment, the differences among the gyros is larger than the
predicted amount of frame-dragging. So, being good scientists,
the GP-B people are not yet prepared to make a claim one way
or the other.
IIRC correctly each of those 4 gyro's was able
to measure the frame-dragging to 1%. Now it
sounds like the error bars are being pushed out
to 100%, (100x) because they didn't find it.
Really? What makes you think that? Have you looked at the data?
Or are you just expressing your general belief in a vast conspiracy
of scientists?
According to the people I've talked to, there is a good chance
that the differences among the gyros can be understood, in part
because the mission had a long calibration run to see how the
gyros responded to various external perturbations. If the
external torques can be modeled, the results should be good
enough to give a fairly good number for frame-dragging. If they
can't, the conclusion will be that the experiment simply wasn't
accurate enough to say.
This sounds like the null result of the MMX,
if you can't find the ether, blame the equipment.
One way or the other, an equipment malfunction
occurred causing an error rate of 100x design
specification OR the frame-dragging effect is
100x less than theory predicted.
Really? What makes you think that? Have you looked at the data?
Or are you just expressing your general belief in a vast conspiracy
of scientists?
Since the geodetic effect banged in well, and no
previous report of 100x equipment design specification
error is indicated, the experiment proves there is
NO frame dragging.
Really? What makes you think that? Have you looked at the data?
Or are you just expressing your general belief in a vast conspiracy
of scientists?
(Clue: What was the expected magnitude of the geodetic effect? What
was the expected magnitude of frame dragging? Do you think that
knowing these might help you make more sensible comments?)
Steve Carlip
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| User: "Ken S. Tucker" |
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| Title: Re: Dragging on |
23 Apr 2007 02:30:42 PM |
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On Apr 23, 10:56 am, wrote:
Ken S. Tucker <dynam...@vianet.on.ca> wrote:
On Apr 21, 6:40 pm, "Daniel G. Emilio" <dge...@gmail.com> wrote:
On Apr 19, 3:20 pm, wrote:
[...]
The third possibility -- which is what is really happening --
is that they won't know whether frame dragging was observed,
and if so, how much, until they understand their systematic
errors better. In particular, the experiment has four
independent gyros, which are observed separately. At the
moment, the differences among the gyros is larger than the
predicted amount of frame-dragging. So, being good scientists,
the GP-B people are not yet prepared to make a claim one way
or the other.
IIRC correctly each of those 4 gyro's was able
to measure the frame-dragging to 1%. Now it
sounds like the error bars are being pushed out
to 100%, (100x) because they didn't find it.
Really? What makes you think that? Have you looked at the data?
Yes, the engineering spec called for 1% accuracy
where the FD effect is to be measured, compared
to (IIRC) the Lageous etc, (previous measurements)
were supposedly calculated to ~ 20-30%.
Or are you just expressing your general belief in a vast conspiracy
of scientists?
Excuse me, I'd do the same as they are. I'd assume
the FD is real and then find if the data can be re-calibrated
to reproduce that result using some rationale. However
that "rationale" now has 100x the error rate, the original
spec called for. So I'll repeat, the goal posts are being
moved, because a 100x error rate is a serious malfunction,
that has NOT been reported.
According to the people I've talked to, there is a good chance
that the differences among the gyros can be understood, in part
because the mission had a long calibration run to see how the
gyros responded to various external perturbations. If the
external torques can be modeled, the results should be good
enough to give a fairly good number for frame-dragging. If they
can't, the conclusion will be that the experiment simply wasn't
accurate enough to say.
This sounds like the null result of the MMX,
if you can't find the ether, blame the equipment.
One way or the other, an equipment malfunction
occurred causing an error rate of 100x design
specification OR the frame-dragging effect is
100x less than theory predicted.
Really? What makes you think that? Have you looked at the data?
Or are you just expressing your general belief in a vast conspiracy
of scientists?
See Steve, it's the repetition of your remarks,
as opposed to a serious discourse that belittles
your reputation as a serious GRist. Of course
if your joking at my expense, fine, but most of
the fella's really respect you.
Since the geodetic effect banged in well, and no
previous report of 100x equipment design specification
error is indicated, the experiment proves there is
NO frame dragging.
Really? What makes you think that? Have you looked at the data?
Or are you just expressing your general belief in a vast conspiracy
of scientists?
Duh.
(Clue: What was the expected magnitude of the geodetic effect?
I noted the error bars were expanded so that the
geodetic effect lost a great deal of precision. In
turn I base that on the need to maintain sufficient
imprecision to permit those same error bars to
expand over the FD effect to ~ 100% = 100x error.
What was the expected magnitude of frame dragging?
About 1/170, I'll use 1/200 ~ 0.5 % for discussion.
Do you think that knowing these might help you make
more sensible comments?
Of course, Steve, has the mission accuracy been
compromised by 100x the error as originally spec'd
in the engineering.
You have "insider" info, taxpayers paid near $billion,
(show a little respect to a fellow taxpayer), do we in
your opinion, suffer a performance compromise from
what we tax-payers bought.
That's a clear question to Dr. Carlip, he can say Yes
or No, or sit on the fence and be disregarded.
Best Wishes
Ken S. Tucker
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| User: "" |
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| Title: Re: Dragging on |
27 Apr 2007 02:14:24 PM |
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Ken S. Tucker <dynamics@vianet.on.ca> wrote:
On Apr 23, 10:56 am, wrote:
[...]
Or are you just expressing your general belief in a vast conspiracy
of scientists?
Excuse me, I'd do the same as they are. I'd assume
the FD is real and then find if the data can be re-calibrated
to reproduce that result using some rationale. However
that "rationale" now has 100x the error rate, the original
spec called for. So I'll repeat, the goal posts are being
moved, because a 100x error rate is a serious malfunction,
that has NOT been reported.
It certainly has been reported. It was discussed in detail at
the APS April meeting, for example; you can even download a
video of Everitt's talk there from the GP-B Web site. The
raw data will be publicly available in June.
Note that your "100x error rate" has a very specific form -- it's
a difference in the precession rates of the four gyros, indicating
that each has a different external torque acting on it. There is
a good chance that these extra torques can be analyzed and eliminated
-- GP-B has a great deal of calibration data measuring the responses
of the gyros to various changes in things like spacecraft orientation
and spin. We'll see.
Steve Carlip
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| User: "Ken S. Tucker" |
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| Title: Re: Dragging on |
27 Apr 2007 02:54:18 PM |
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On Apr 27, 12:14 pm, wrote:
Ken S. Tucker <dynam...@vianet.on.ca> wrote:
On Apr 23, 10:56 am, wrote:
[...]
Or are you just expressing your general belief in a vast conspiracy
of scientists?
Excuse me, I'd do the same as they are. I'd assume
the FD is real and then find if the data can be re-calibrated
to reproduce that result using some rationale. However
that "rationale" now has 100x the error rate, the original
spec called for. So I'll repeat, the goal posts are being
moved, because a 100x error rate is a serious malfunction,
that has NOT been reported.
It certainly has been reported. It was discussed in detail at
the APS April meeting, for example; you can even download a
video of Everitt's talk there from the GP-B Web site. The
raw data will be publicly available in June.
Note that your "100x error rate" has a very specific form -- it's
a difference in the precession rates of the four gyros, indicating
that each has a different external torque acting on it. There is
a good chance that these extra torques can be analyzed and eliminated
-- GP-B has a great deal of calibration data measuring the responses
of the gyros to various changes in things like spacecraft orientation
and spin. We'll see.
Rhetorical questions...
s/c spin???, I thought GP-b was, within it's canister,
an "inertial frame", within it's small volume, meaning
no spin effects induced by the nature of the s/c.
Wasn't the idea for using micro thrusters to alleviate
the effects of atmospherical braking for the same reason,
to keep the gyros in a "perfect inertial frame".
Roger, I mean Steve, "We'll see".
Regards and thanks for the info.
Ken S. Tucker
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| User: "Sue..." |
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| Title: Re: Dragging on |
23 Apr 2007 03:27:24 PM |
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On Apr 23, 2:56 pm, wrote:
Ken S. Tucker <dynam...@vianet.on.ca> wrote:
On Apr 21, 6:40 pm, "Daniel G. Emilio" <dge...@gmail.com> wrote:
On Apr 19, 3:20 pm, wrote:
[...]
The third possibility -- which is what is really happening --
is that they won't know whether frame dragging was observed,
and if so, how much, until they understand their systematic
errors better. In particular, the experiment has four
independent gyros, which are observed separately. At the
moment, the differences among the gyros is larger than the
predicted amount of frame-dragging. So, being good scientists,
the GP-B people are not yet prepared to make a claim one way
or the other.
IIRC correctly each of those 4 gyro's was able
to measure the frame-dragging to 1%. Now it
sounds like the error bars are being pushed out
to 100%, (100x) because they didn't find it.
Really? What makes you think that? Have you looked at the data?
Or are you just expressing your general belief in a vast conspiracy
of scientists?
If the Lens-Thirring ~interpretation~ is wrong it won't matter how
far you push the error bars... and the evidence
against it is stronger than the evidence for it.
<<... a superconductive gyroscope is capable of generating
a powerful gravitomagnetic field, and is therefore the
gravitational counterpart of the magnetic coil. Depending
on further confirmation, this effect could form the basis for
a new technological domain, which would have numerous
applications in space and other high-tech sectors" says
ESA study manager Clovis de Matos. Although just 100
millionths of the acceleration due to the Earth's gravitational
field, the measured field is a surprising one hundred million
trillion times larger than Einstein's General Relativity
predicts. >>
http://www.esa.int/SPECIALS/GSP/SEM0L6OVGJE_0.html
Einstein isn't even offer enthusiastic about a coupling
to *space* in 1923.
<<... Newton recognized that the
law of inertia is unsatisfactory
in a context so far unmentioned in this
exposition, namely that it gives no
real cause for the special physical
position of the states of motion of the
inertial frames relative to all other
states of motion. It makes the observable
material bodies responsible for the
gravitational behaviour of a material
point, yet indicates no material cause
for the inertial behaviour of the material
point but devises the cause for it
(absolute space or inertial ether). This
is not logically inadmissible although
it is unsatisfactory. For this reason
E. Mach demanded a modification of the
law of inertia in the sense that the
inertia should be interpreted as an
acceleration resistance of the bodies
against one another and not against "space".
This interpretation governs the expectation
that accelerated bodies have concordant
accelerating action in the same
sense on other bodies (acceleration induction).
This interpretation is even more
plausible according to general relativity
which eliminates the distinction between
inertial and gravitational effects. >>
http://nobelprize.org/nobel_prizes/physics/laureates/1921/einstein-lecture.html
Sue...
According to the people I've talked to, there is a good chance
that the differences among the gyros can be understood, in part
because the mission had a long calibration run to see how the
gyros responded to various external perturbations. If the
external torques can be modeled, the results should be good
enough to give a fairly good number for frame-dragging. If they
can't, the conclusion will be that the experiment simply wasn't
accurate enough to say.
This sounds like the null result of the MMX,
if you can't find the ether, blame the equipment.
One way or the other, an equipment malfunction
occurred causing an error rate of 100x design
specification OR the frame-dragging effect is
100x less than theory predicted.
Really? What makes you think that? Have you looked at the data?
Or are you just expressing your general belief in a vast conspiracy
of scientists?
Since the geodetic effect banged in well, and no
previous report of 100x equipment design specification
error is indicated, the experiment proves there is
NO frame dragging.
Really? What makes you think that? Have you looked at the data?
Or are you just expressing your general belief in a vast conspiracy
of scientists?
(Clue: What was the expected magnitude of the geodetic effect? What
was the expected magnitude of frame dragging? Do you think that
knowing these might help you make more sensible comments?)
Steve Carlip
.
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| User: "Raving" |
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| Title: Gravity probe measures Earth's dent in space-time |
17 Apr 2007 04:52:48 PM |
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On Apr 17, 1:08 am, Sam Wormley <sworml...@mchsi.com> wrote:
Dragging on
http://cosmicvariance.com/2007/04/15/dragging-on/
The annual April meeting of the American Physical Society is
currently underway. This meeting brings together thousands of
physicists, from all branches except condensed matter. The condensed
matter types have their own meeting (in March), which dwarfs ours.
For the next few days, there will be a flurry of press releases
originating in Jacksonville, Florida. Although I have been missing
the action down south, there is one press release which was
conspicuous in its absence. A measurement of frame dragging was not
announced by theGravityProbeB satellite (affectionately known as
GP-B), as originally planned. Instead, NASA issued an Interim Report
summarizing the state of the data analysis thus far. The press
release is here.
See:http://cosmicvariance.com/2007/04/15/dragging-on/
Gravity probe measures Earth's dent in space-time
* 17:32 16 April 2007
* NewScientist.com news service
* Valerie Jamieson, Jacksonville
A NASA mission that took 40 years to get off the drawing board has
finally measured how the Earth dents the fabric of space-time.
The first result from the Gravity Probe B satellite confirms a
prediction of Einstein's general theory of relativity to a precision
of better than 1%. "For the first time, we have seen one of Einstein's
effects directly," says mission leader Francis Everitt of Stanford
University in California, US. ...
http://space.newscientist.com/article.ns?id=dn11615&feedId=online-news_rss20
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| User: "nightbat" |
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| Title: Re: Gravity probe measures Earth's dent in space-time |
18 Apr 2007 01:44:00 AM |
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nightbat wrote
Raving wrote:
On Apr 17, 1:08 am, Sam Wormley <sworml...@mchsi.com> wrote:
Dragging on
http://cosmicvariance.com/2007/04/15/dragging-on/
The annual April meeting of the American Physical Society is
currently underway. This meeting brings together thousands of
physicists, from all branches except condensed matter. The condensed
matter types have their own meeting (in March), which dwarfs ours.
For the next few days, there will be a flurry of press releases
originating in Jacksonville, Florida. Although I have been missing
the action down south, there is one press release which was
conspicuous in its absence. A measurement of frame dragging was not
announced by theGravityProbeB satellite (affectionately known as
GP-B), as originally planned. Instead, NASA issued an Interim Report
summarizing the state of the data analysis thus far. The press
release is here.
See:http://cosmicvariance.com/2007/04/15/dragging-on/
Gravity probe measures Earth's dent in space-time
* 17:32 16 April 2007
* NewScientist.com news service
* Valerie Jamieson, Jacksonville
A NASA mission that took 40 years to get off the drawing board has
finally measured how the Earth dents the fabric of space-time.
The first result from the Gravity Probe B satellite confirms a
prediction of Einstein's general theory of relativity to a precision
of better than 1%. "For the first time, we have seen one of Einstein's
effects directly," says mission leader Francis Everitt of Stanford
University in California, US. ...
http://space.newscientist.com/article.ns?id=dn11615&feedId=online-news_rss20
nightbat
Thanks for that excellent report Officer Raving, keep up the
good work.
as you were,
the nightbat
.
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