LIGO Progress

Does anyone have any new information on anything new being done to the LIGO
detector?
After hearing the LIGO gravity wave detector was not sensitive enough to
detect gravity waves what are the steps being done to fix it? Are they
planning to rip the guts out of it?
That project sucked quite a bit of money out of the NSF piggy bank and I
hope more funds are not going to be solicited unlessss they’re absolutely
sure LIGO is going to work.

"Mike" wrote in message
news:v45Vf.9083$6%2.5456@trnddc08...
Does anyone have any new information on anything new being done to the
LIGO
detector?
After hearing the LIGO gravity wave detector was not sensitive enough to
detect gravity waves what are the steps being done to fix it? Are they
planning to rip the guts out of it?
That project sucked quite a bit of money out of the NSF piggy bank and I
hope more funds are not going to be solicited unlessss they’re absolutely
sure LIGO is going to work.

LIGO will work (and they are already working
on LIGO 2 which improves the sensitivity) but
whether it will detect gravitational waves is
another matter. The point is that a null result
at a sensitivity better than predicted for
detection would also be significant.

George

"George Dishman" wrote in message
...

"Mike" wrote in message
news:v45Vf.9083$6%2.5456@trnddc08...
Does anyone have any new information on anything new being done to the
LIGO
detector?
After hearing the LIGO gravity wave detector was not sensitive enough to
detect gravity waves what are the steps being done to fix it? Are they
planning to rip the guts out of it?
That project sucked quite a bit of money out of the NSF piggy bank and I
hope more funds are not going to be solicited unlessss they're absolutely
sure LIGO is going to work.

LIGO will work (and they are already working
on LIGO 2 which improves the sensitivity) but
whether it will detect gravitational waves is
another matter. The point is that a null result
at a sensitivity better than predicted for
detection would also be significant.

George



.... a significant waste of money!

But it won't be - they computer post-process the data, and answers they get
will be have to be probabilities. So they will say "almost certain" or "very
likely". And the calculations can reasonably only be done on their own
computers, and so the realistic options for peer review are zero, the
incentive for exaggeration is enormous.

"Peter Webb" wrote in message
...

"George Dishman" wrote in message
...

"Mike" wrote in message
news:v45Vf.9083$6%2.5456@trnddc08...
Does anyone have any new information on anything new being done to the
LIGO
detector?
After hearing the LIGO gravity wave detector was not sensitive enough to
detect gravity waves what are the steps being done to fix it? Are they
planning to rip the guts out of it?
That project sucked quite a bit of money out of the NSF piggy bank and I
hope more funds are not going to be solicited unlessss they're
absolutely
sure LIGO is going to work.

LIGO will work (and they are already working
on LIGO 2 which improves the sensitivity) but
whether it will detect gravitational waves is
another matter. The point is that a null result
at a sensitivity better than predicted for
detection would also be significant.

George



... a significant waste of money!

But it won't be - they computer post-process the data, and answers they
get will be have to be probabilities.

The answers they get will be something like
probable amplitudes for waves from specific
sources and can be compared against known
objects in those locations

So they will say "almost certain" or "very likely". And the calculations
can reasonably only be done on their own computers, and so the realistic
options for peer review are zero, the incentive for exaggeration is
enormous.

The data is what it is. The algorithms used
can and will be reviewed. It is also possible
that the data will be independently reprocessed
as Markwardt did for the Anderson data on Pioneer

http://www.arxiv.org/abs/gr-qc/0208046

Those who exaggerate tend to get found out.

George

Mike wrote:
Does anyone have any new information on anything new being done to the LIGO
detector?

LIGO has only quite recently reached its design sensitivity. A year-long
"science run" began in mid-November (it will actually run about a year and
a half to collect a full year's data).

After hearing the LIGO gravity wave detector was not sensitive enough to
detect gravity waves what are the steps being done to fix it?

It's not at all clear that "the LIGO gravity wave detector was not sensitive
enough to detect gravity waves." The basic problem is that detectability
depends on how far away a source is, and we don't have good estimates of
-- for instance -- how many neutron star binaries there are in the galaxy.
It is still quite possible that interesting things will be seen in the
current run.

Are they planning to rip the guts out of it?

There are well-developed plans for "Advanced LIGO," with many elements
now in the development and testing stage. The sensitivity will increase
by a factor of ten. This means that Advanced LIGO will be able to see
sources in 1000 times the spatial volume that LIGO can. Current plans
are for Advanced LIGO to start observations in 2013.

If Advanced LIGO fails to see anything, that failure will in itself be
a major result -- it will be a demonstration that our current understanding
of gravitational radiation is wildly wrong. If this is the case, it's
worth knowing. If it does see gravitational radiation, it will allow us
to look at processes we cannot otherwise see at all -- for example, the
merger of a pair of black holes.

Steve Carlip

For what's its worth I still believe if the LIGO detectors were moving at
least few miles per second in free space the detection of these elusive
waves would be more forth coming.

While it was pointed out earlier that in a relative sense the LIGO detectors
were in fact moving. To me that statement gives the impression the apparatus
is being fed a diet of stale bread and crackers when it should be afforded
the red carpet treatment.

Thanks, your responses are most informative.

"George Dishman" wrote in message
...

"Peter Webb" wrote in message
...

"George Dishman" wrote in message
...

"Mike" wrote in message
news:v45Vf.9083$6%2.5456@trnddc08...
Does anyone have any new information on anything new being done to the
LIGO
detector?
After hearing the LIGO gravity wave detector was not sensitive enough
to
detect gravity waves what are the steps being done to fix it? Are they
planning to rip the guts out of it?
That project sucked quite a bit of money out of the NSF piggy bank and
I
hope more funds are not going to be solicited unlessss they're
absolutely
sure LIGO is going to work.

LIGO will work (and they are already working
on LIGO 2 which improves the sensitivity) but
whether it will detect gravitational waves is
another matter. The point is that a null result
at a sensitivity better than predicted for
detection would also be significant.

George



... a significant waste of money!

But it won't be - they computer post-process the data, and answers they
get will be have to be probabilities.

The answers they get will be something like
probable amplitudes for waves from specific
sources and can be compared against known
objects in those locations

Any idea of the spatial resolution provided by LIGO 1? And unless the
resolution is of the order of a few arc-seconds, how will they know what
object generated the signal?



So they will say "almost certain" or "very likely". And the calculations
can reasonably only be done on their own computers, and so the realistic
options for peer review are zero, the incentive for exaggeration is
enormous.

The data is what it is. The algorithms used
can and will be reviewed. It is also possible
that the data will be independently reprocessed
as Markwardt did for the Anderson data on Pioneer

http://www.arxiv.org/abs/gr-qc/0208046


That is a link to a review of a different and far easier data set.

Have you any corresponding evidence that the LIGO data can or will be
subject to external review?


Those who exaggerate tend to get found out.

George


And those who publish completely irrelevant links also get found out.

"PW" == Peter Webb writes:

PW Any idea of the spatial resolution provided by LIGO 1? And unless
PW the resolution is of the order of a few arc-seconds, how will they
PW know what object generated the signal?

That's a very good question. I know that at least some people
associated with LIGO are thinking about this problem, namely, suppose
they think they've found a result---will anybody else, will they
themselves, accept it unless some electromagnetic counterpart is found.

In fact, one of the things I've heard mentioned is that LIGO would
take triggers from other telescopes so as to provide the direction
(actually the timing) for the putative gravitational wave signal,
which would help make the analysis easier.

--
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"M" == Mike writes:

M For what's its worth I still believe if the LIGO detectors were
M moving at least few miles per second in free space the detection of
M these elusive waves would be more forth coming.

I find this a fascinating statement. A ground-based experiment
costing of order $200M is described as a potential waste of money, but
putting it in space without first testing it on the ground is
considered fiscally responsible?

Putting anything in space is tremendously expensive. Doing a
ground-based test, to the maximum extent possible, in order to work
out the bugs is always a good idea.

--
Lt. Lazio, HTML police | e-mail:
No means no, stop rape. | http://patriot.net/%7Ejlazio/
sci.astro FAQ at http://sciastro.astronomy.net/sci.astro.html