LIGO gravitational wave announcement

[hecd2]

Miles Mathis has been off-form recently, but he has made a magnificent come-back with this "article" on the LIGO discovery here. The whole thing is stuffed with priceless assertions, but this one, as a preamble to some epic numerology, is particularly, shall we say, entertaining (referring to the gravitationlal wave signal): "Since the frequency is 128 Hz at .42 seconds, that is a frequency of about 300 at one second, and that corresponds to a wavelength
of about 10^5 meters".

The rest of tte article isn't far behind. As performance art, it's brilliant, but I wonder whether he's beginning to believe himself? His hubris is approaching Myron Evans-like proportions as are some of his rants: "In conclusion, what we have here is not an exciting scientific discovery, it is another discovery of massive fraud. Since billions of dollars were bilked from the treasury under false pretexts, these people should be arrested and charged under the proper laws."

 

[Elind]

Do gravitational waves get delayed by gravity wells?

To clarify, it's not directly "delayed", but redirected by gravitational lensing which lengthens the path taken.

As to whether the same effect applies to gravity waves; it's a good question. I don't know.

 

[W.D.Clinger]

Miles Mathis has been off-form recently, but he has made a magnificent come-back with this "article" on the LIGO discovery here. The whole thing is stuffed with priceless assertions, but this one, as a preamble to some epic numerology, is particularly, shall we say, entertaining (referring to the gravitationlal wave signal): "Since the frequency is 128 Hz at .42 seconds, that is a frequency of about 300 at one second, and that corresponds to a wavelength of about 10^5 meters".

That reminds me of a news article that discussed possible global warming of "2 degrees Celsius (35.6 degrees Fahrenheit)".

 

[smartcooky]

"Since the frequency is 128 Hz at .42 seconds, that is a frequency of about 300 at one second, and that corresponds to a wavelength of about 10^5 meters".

So, math is not his strong point eh!?

(See what I did there)

 

[alexi_drago]

Which radio station he listens to depends on how long he's listening.

 

[Elind]

To clarify, it's not directly "delayed", but redirected by gravitational lensing which lengthens the path taken.

As to whether the same effect applies to gravity waves; it's a good question. I don't know.

Adding to my own point; if gravity waves behave similarly to electromagnetic, photon, ones in gravity fields then one would expect that they don't follow the same exact path since the wavelengths are so vastly different.

 

[Mikemcc]

Adding to my own point; if gravity waves behave similarly to electromagnetic, photon, ones in gravity fields then one would expect that they don't follow the same exact path since the wavelengths are so vastly different.

No, they actually behave differently. GW wave propagate at the speed of light, but are affected by gravitational lensing. EM radiation is also affected by lensing but also the media it is propagating through.

Sent from my GT-I9505 using Tapatalk

 

[Elind]

No, they actually behave differently. GW wave propagate at the speed of light, but are affected by gravitational lensing. EM radiation is also affected by lensing but also the media it is propagating through.

Sent from my GT-I9505 using Tapatalk

You don't address my point regarding differences in lensing due to wavelength. However while I am no expert, I read enough to feel pretty sure that "media" in interstellar (or inter galaxy) has no significant effect on the speed of photons other than possibly changing their polarization or frequency/wavelength.

 

[macdoc]

Question ..

what other phenomena COULD trigger a ligo detection in both locations and NOT be a gravitational wave ?

 

[marplots]

Question ..

what other phenomena COULD trigger a ligo detection in both locations and NOT be a gravitational wave ?

Telekinesis.
God.

We've been looking for evidence and here it is!

 

[macdoc]

Sort of what I figured...the design and noise cancelling procedures nearly rule out strong false positives beyond the devils in the "injection room".

 

[Mark the Hiker]

I have a question regarding energy transfer by gravitational waves. When this wave passed through the detectors, it moved the mirrors by a very small amount. Does this mean that the wave actually imparted momentum to the mirrors, or does the fact that space itself was bent negate that? Do these waves lose energy/amplitude when they pass through a mass?

I understand that the momentum transferred would be very slight, but would it be exactly zero?

 

[rjh01]

Question ..

what other phenomena COULD trigger a ligo detection in both locations and NOT be a gravitational wave ?

There could be a lot of false positives. They check with the other detectors and eventually by the laws of probability the other stations also have a false positive at the time, so it is mistaken for a true signal.

I do not think it is this, but will have to wait to find more signals. We need more detectors and better ones so that more waves can be detected and confirmed in real time.

 

[macdoc]

Did not answer my question....what could cause a false positive in two detectors a long way apart.

 

[rjh01]

Did not answer my question....what could cause a false positive in two detectors a long way apart.

Let me put it another way. Coincidence.

I want to know what is the of rate false positives that are detected in one detector. Then we can work out the chance that this was a coincidence.

 

[MikeG]

There could be a lot of false positives. They check with the other detectors and eventually by the laws of probability the other stations also have a false positive at the time, so it is mistaken for a true signal.

I do not think it is this, but will have to wait to find more signals. We need more detectors and better ones so that more waves can be detected and confirmed in real time.

You might have a point if there were any false positives recorded. My understanding, from a BBC radio programme on the subject, is that there were no other signals recorded at all in 3 years.

 

[macdoc]

exactly

rjh01

Let me put it another way. Coincidence.

I want to know what is the of rate false positives that are detected in one detector. Then we can work out the chance that this was a coincidence.

I don't think you understand the tech very well.

WHAT is it you think CAN trigger a false positive.?

 

[rjh01]

You might have a point if there were any false positives recorded. My understanding, from a BBC radio programme on the subject, is that there were no other signals recorded at all in 3 years.

My understanding is that they have just turned it on after an upgrade. There has been no time to find out how many false positives there are. Yes, the machine had been on before the upgrade but it was nowhere near as sensitive as it is now.

Though yes, I agree I am probably wrong. I even said that in my first post on the subject. I am looking forward to another announcement saying the are detecting one every few months. That would be a good reason to build more and better detectors.

 

[Craig B]

My understanding is that they have just turned it on after an upgrade. There has been no time to find out how many false positives there are. Yes, the machine had been on before the upgrade but it was nowhere near as sensitive as it is now.

Though yes, I agree I am probably wrong. I even said that in my first post on the subject. I am looking forward to another announcement saying the are detecting one every few months. That would be a good reason to build more and better detectors.

PhysicsWorld http://physicsworld.com/cws/article...ghts-emerge-from-ligo-gravitational-wave-data had an interesting report on 15 Feb.

Researchers from the LIGO collaboration who last week announced they had detected the first ever gravitational waves – spewed out from two merging black holes – have also picked up a second possible gravitational-wave event. Although the signal from "LVT151012" is much weaker than the confirmed “GW150914” event, the LIGO team says it most likely has an astrophysical source and arose from two coalescing black holes. The researchers have in addition spotted “several even less significant events in the data, most likely just due to some disturbance at the detectors", which they are now analysing to see if any are from gravitational waves. Their conclusions, expected over the course of this year, will see the new era of gravitational-wave astronomy finally start ... These events suggest that the rate of binary-black-hole mergers is higher than expected, between six and 400 per cubic gigaparsec per year.​

 

[smartcooky]

You might have a point if there were any false positives recorded. My understanding, from a BBC radio programme on the subject, is that there were no other signals recorded at all in 3 years.

That is my understanding as well. There isn't anything that these detectors could detect other than GWs.

They are very sensitive to seismic events (both natural and man-made ground vibrations), but they compensate for that, and besides, the observatory "listens" for seismic activity.