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Old 16th February 2016, 07:00 AM   #241
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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."
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Old 16th February 2016, 07:27 AM   #242
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Originally Posted by Craig B View Post
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.
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Old 16th February 2016, 07:34 AM   #243
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Originally Posted by hecd2 View Post
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)".
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Old 16th February 2016, 12:06 PM   #244
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Originally Posted by hecd2 View Post
"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)
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Old 16th February 2016, 12:34 PM   #245
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Which radio station he listens to depends on how long he's listening.
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Last edited by alexi_drago; 16th February 2016 at 12:35 PM.
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Old 16th February 2016, 03:41 PM   #246
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Originally Posted by Elind View Post
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.
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Old 16th February 2016, 05:02 PM   #247
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Originally Posted by Elind View Post
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.

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Old 16th February 2016, 05:31 PM   #248
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Originally Posted by Mikemcc View Post
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.

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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.
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Old 16th February 2016, 06:43 PM   #249
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Question ..

what other phenomena COULD trigger a ligo detection in both locations and NOT be a gravitational wave ?
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Old 16th February 2016, 06:50 PM   #250
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Originally Posted by macdoc View Post
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!
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Old 16th February 2016, 07:00 PM   #251
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Sort of what I figured...the design and noise cancelling procedures nearly rule out strong false positives beyond the devils in the "injection room".
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Old 16th February 2016, 08:04 PM   #252
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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?
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Old 16th February 2016, 10:09 PM   #253
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Originally Posted by macdoc View Post
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.
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Old 16th February 2016, 10:38 PM   #254
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Did not answer my question....what could cause a false positive in two detectors a long way apart.
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Old 16th February 2016, 11:43 PM   #255
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Originally Posted by macdoc View Post
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.
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Old 17th February 2016, 12:35 AM   #256
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Originally Posted by rjh01 View Post
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.
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Old 17th February 2016, 01:39 AM   #257
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exactly

rjh01
Quote:
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.?
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Old 17th February 2016, 03:56 AM   #258
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Originally Posted by MikeG View Post
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.
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Old 17th February 2016, 04:13 AM   #259
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Originally Posted by rjh01 View Post
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/...onal-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.
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Old 17th February 2016, 04:17 AM   #260
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Originally Posted by MikeG View Post
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.
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Old 17th February 2016, 04:24 AM   #261
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Originally Posted by Elind View Post
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.
That's because I'm unsure of the answer concerning the effects of the wavelength and gravitational lensing and didn't want to give a potentially wrong one.

Whilst the effects on the speed of light are very small in interstellar space the distances involved are huge, so even small effects are detectable. There are time differences between X-ray and visible light propagation times (used to watch for GMBs and novas). The Gravitational Waves are different in that they aren't slowed in the way that light is.
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Old 17th February 2016, 11:45 AM   #262
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Originally Posted by JeanTate View Post
Originally Posted by Cl1mh4224rd
Not much, apparently:

Originally Posted by Dr. Amber Stuver
Now assume that we are 2 m (~6.5 ft) tall and floating outside the black holes at a distance equal to the Earth’s distance to the Sun. I estimate that you would feel alternately squished and stretched by about 165 nm (your height changes by more than this through the course of the day due to your vertebrae compressing while you are upright). This is more than survivable.
Your Questions About Gravitational Waves, Answered
Thanks!

Now what would be really, really terrific is at least an overview of how she arrived at her estimate, like a BOTE calculation ...
Here's my BOTE (Back Of The Envelope) calc:

Strain observed by LIGO: 10^-21
Length of a LIGO arm: 4 km
Amplitude of GW observed: 4x10^-18 m
Distance to GW150914: 410 Mpc
Distance ratio, 410 Mpc/1 au: 8.5x10^13
Strain at 1 au from BBH merger: 8.5x10^-8
Amplitude of GW at 1 au, for a 2m object (e.g. a tall human): 1.7x10^-7 m

Which is 170 nm, in agreement with Dr. Amber Stuver. Yay!

Like many people, I had assumed that what was observed follows an inverse square relationship ... that's true for the energy of the GW, but what was observed was the amplitude, which goes as inverse distance!

"like many people"? One was Scott Aaronson, in his blog post The universe has a high (but not infinite) Sleep Number The blog post ends with this:
Originally Posted by Scott Aaronson
As if I needed to say it, this post is an invitation for experts to correct whatever I got wrong. Public humiliation, I’ve found, is a very fast and effective way to learn an unfamiliar field.
The blog post, and the comments, are a delight to read.
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Old 18th February 2016, 07:35 PM   #263
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For anybody interested, there is an absolutely hilarious thread on this by the geniuses at Dunderdolts: http://www.thunderbolts.info/forum/p...hp?f=3&t=16172
Well worth a read if you are running out of things to find funny.
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Old 18th February 2016, 07:58 PM   #264
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Originally Posted by jonesdave116 View Post
For anybody interested, there is an absolutely hilarious thread on this by the geniuses at Dunderdolts: http://www.thunderbolts.info/forum/p...hp?f=3&t=16172
Well worth a read if you are running out of things to find funny.
Weird. What is this obsession with electricity that they apply to anything?
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Old 18th February 2016, 09:12 PM   #265
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Originally Posted by jonesdave116 View Post
For anybody interested, there is an absolutely hilarious thread on this by the geniuses at Dunderdolts: http://www.thunderbolts.info/forum/p...hp?f=3&t=16172
Well worth a read if you are running out of things to find funny.
Originally Posted by Elind View Post
Weird. What is this obsession with electricity that they apply to anything?

Reading the stupidity of electric universe nitwits as they discuss/dismiss GWs is somewhat reminiscent of a cartoon I once saw many years ago, in which a couple of Daleks (original ones) are at the foot of a flight of stairs, and one is saying to the other.....

"Well, this stuffs our plans to conquer the universe!!"
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Old 18th February 2016, 10:22 PM   #266
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Not read the entire thread recently and only read a little of it just now. I do not think though, how they knew the size of the black holes. It has just occurred to me how they might have done it. The waves they detected are the sum of two sine waves. The amplitude of each wave is related to the size of one of the black holes. So that gives them the relative sizes of the black holes. They then work out the absolute size of the black holes by noting at how fast they were orbiting each other when they merged. Once they know the absolute size of the black holes it is easy to work out the distance from earth they are.

How close am I to the facts? If I am wrong wheat is the correct answer?
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Old 19th February 2016, 12:31 AM   #267
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Originally Posted by rjh01 View Post
........If I am wrong wheat is the correct answer?
I don't know, but I'm pretty sure it isn't this
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Old 19th February 2016, 11:55 AM   #268
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Originally Posted by jonesdave116 View Post
For anybody interested, there is an absolutely hilarious thread on this by the geniuses at Dunderdolts: http://www.thunderbolts.info/forum/p...hp?f=3&t=16172
Well worth a read if you are running out of things to find funny.
I, uh, I guess I need to get out more. I didn't even know that there are people who are certain that gravity waves travel way faster than c. When did this happen and where did these people come from? More importantly-what the hell are they basing this on?
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Old 19th February 2016, 04:20 PM   #269
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Originally Posted by DuvalHMFIC View Post
More importantly-what the hell are they basing this on?

Observations of their local brown hole would be my guess...
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Old 19th February 2016, 04:43 PM   #270
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Originally Posted by DuvalHMFIC View Post
<snip>

More importantly-what the hell are they basing this on?
Good luck with getting a clear answer to that!

One source is a guy, now dead, who proposed a wide range of crackpot ideas; another is their personal intuition, in which 'common sense' plays a central role.

An example: the gravitational pull of the Sun, on the Earth, seems, to us here on the Earth, to 'point' directly at the Sun. In Newtonian gravity, this is easy to understand, because gravity 'propagates' instantaneously. In GR, you'd expect the 'pointing' to lag somewhat, due to the delay in gravity propagating at c. But it doesn't!

There's no contradiction; if you work through the (tough!) GR math, you'll find that gravity 'points' in the exact direction determined by experiment/observation. However, EU fanatics don't 'do math', they rely upon personal intuition ... therefore, to them, gravity travels at a speed far exceeding c ...
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Old 20th February 2016, 10:20 AM   #271
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Excellent article on the history and uncertainty of GW.

Quote:
Even Einstein Didn't Think Gravitational Waves Existed

Wired Science
For 20 years Albert Einstein equivocated about gravitational waves, unsure whether these undulations in the fabric of space and time were predicted or ruled out by his revolutionary 1915 theory of general relativity.
http://www.wired.com/2016/02/even-ei...waves-existed/

Note Feynman's sticky bead argument ....that's a visual.....and had an important role to play in the search for GW

snip
Quote:
“Well, since we know that the particles move, all we have to do is imagine a stick, and on the stick we can put some beads. As the wave passes by, the beads will move back and forth, but the stick will stay rigid because the electromagnetic forces in the stick will try to keep the atoms and electrons in the same positions as they were previously. So the beads will drag against the stick, and the friction will produce energy. And the energy must have come from the gravitational wave. So I conclude that the wave has energy.” So this famous “sticky bead” thought experiment convinced a lot of people that there wasn’t any reason for the skepticism that Rosen had advanced. And then people like Joe Weber started trying to detect gravitational waves shortly after.

Quote:
Einstein showed in 1918 that dumbbell-like systems that rotate about two axes at once, such as binary stars, radiate gravitational waves
wow - effective graphic showing theory prediction versus actual detection


Quote:
The gravitational-wave “chirp” observed by Advanced LIGO’s Hanford (top left) and Livingston (top right) detectors, compared to theoretical predictions (bottom row) of the chirp from two black holes of 29 and 36 solar masses, respectively, merging 1.3 billion light-years away. B. P. ABBOTT ET AL., OBSERVATION OF GRAVITATIONAL WAVES FROM A BINARY BLACK HOLE MERGER, PHYS. REV. LETT. 116, 061102
story conclusion .....this should be in everyone's lexicon of "How science works"...

Quote:
There’s this hope that LIGO will “open up a new window on the universe” by detecting gravitational waves from previously unknown astrophysical objects. Considering the effort that went into recognizing the signal from a black-hole merger, how will we be able to see the unexpected?

Yes, the real excitement would be to find something we didn’t expect. One possibility is that the unexpected might help us out by being a very large signal. Our hopes for that have been dampened somewhat, because the original LIGO was online for quite a while and if the signal were very large it might have seen it. It does look like the unexpected is not going to be easy, so how do we dig the signal out of the noise?

One answer is that there are certain kinds of techniques that people have been looking at where you don’t commit yourself to knowing precisely what the signal looks like, but you just look for certain kinds of regularities—for instance, maybe this unexpected signal is at least a periodic signal. And LIGO is certainly doing that. They even have an “Einstein@Home” project, where they’ll send a piece of LIGO data to your home computer if you sign up for this, and your computer will help look for simple things like that. Another approach is to use machine learning to try to teach machines to look for signals. You start with what you know, but there is some hope that over time these techniques might grow and develop to where they become sufficiently flexible to catch things that aren’t what you expect.


What do you take away from this story?

I am struck by the collective nature of the endeavor. It had to be a collaborative effort; each step was sufficiently difficult that it had to link to the next step. And collective efforts come with vitriol and disputes. People shouted at each other. But the finer qualities of human nature won out. People got over their anger. Einstein got over his anger. People admitted they were wrong. And eventually, as a community, we got there.
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Old 20th February 2016, 02:35 PM   #272
smartcooky
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Originally Posted by JeanTate View Post
An example: the gravitational pull of the Sun, on the Earth, seems, to us here on the Earth, to 'point' directly at the Sun. In Newtonian gravity, this is easy to understand, because gravity 'propagates' instantaneously. In GR, you'd expect the 'pointing' to lag somewhat, due to the delay in gravity propagating at c. But it doesn't!

There's no contradiction; if you work through the (tough!) GR math, you'll find that gravity 'points' in the exact direction determined by experiment/observation. However, EU fanatics don't 'do math', they rely upon personal intuition ... therefore, to them, gravity travels at a speed far exceeding c ...
I don't think you even need the math actually, I think all you have to do is look at what the two theories propose

If gravity were a force as Newton suggested, but travelling at c then the lag of one object orbiting the other would exist.... the forces would not "point" directly at each other

However, gravity is not a force, its a three dimensional distortion of the fabric of spacetime. That distortion "exists where it exists" regardless of the relative speeds of the two objects.

NOTE: Regardless of what someone else has said here, its not difficult to visualize the distortion in 3D; I have no trouble doing it.


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Old 20th February 2016, 02:37 PM   #273
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What happened in the nearby vicinity when those two BH coalesced?

Talking about distances like our solar system. How big was the gravitational wave impact to nearby objects?
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Old 20th February 2016, 04:32 PM   #274
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Originally Posted by carlosy View Post
What happened in the nearby vicinity when those two BH coalesced?

Talking about distances like our solar system. How big was the gravitational wave impact to nearby objects?
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Old 20th February 2016, 06:54 PM   #275
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about right....most everything in a solar system radius would be included in the sudden conversion of 3 solar masses to energy....the most giantest flashbulb evah.
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Old 20th February 2016, 07:23 PM   #276
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Originally Posted by macdoc View Post
about right....most everything in a solar system radius would be included in the sudden conversion of 3 solar masses to energy....the most giantest flashbulb evah.
Hold on a minute there. The wave may contain 3 solar masses of energy, directed in all three dimensions equally, and there is no suggestion that any time it encounters an object with mass it transfers all that energy to the mass it encounters. If it did it would never survive a billion or more light years of space travel. In any case it is not an interactive energy wave, it is a modification of space time. I question if it actually deposited any energy to the detectors at all. Many things are detectable without drawing energy from them.
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Old 21st February 2016, 12:38 AM   #277
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Quote:
The wave may contain 3 solar masses of energy,
This is incorrect...

What do thing the big flash was? .....the gravitational wave was a RESULT of the ginormous conversion of mass to energy....we didn't see the flash...anything within a solar system distance was blasted to whatever raw bits apply by that 50 x output of all the stars in the universe flash.

The gravitational wave occurred because of the abrupt change in mass that occurred as a result of the conversion of mass to energy.
That change in mass generated the gravitational wave,.
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Old 21st February 2016, 02:11 AM   #278
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So, how close would a human had to be to notice the gravitational wave itself (not the energy blast / em-waves) on his own body? Would that even be possible?

Last edited by carlosy; 21st February 2016 at 02:13 AM.
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Old 21st February 2016, 02:18 AM   #279
Craig B
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Originally Posted by carlosy View Post
So, how close would a human had to be to notice the gravitational wave itself (not the energy blast / em-waves) on his own body? Would that even be possible?
I already asked that, more or less, at #108.
I was wondering what would have happened if we had been much closer to the event, so that let's say the arms of the LIGO momentarily changed length by a hundred metres. Would that have caused utter disruption of all material structures, including the planet, or would it just have rippled past leaving things as unaffected as is a cork floating on a pond agitated by a breeze?
The responses I received haven't really enlightened me, I must admit.
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Old 21st February 2016, 02:24 AM   #280
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I think there is a conceptal issue here....you don't "notice" curved space you notice the change in gravity that causes the change to the curve in space which a gravitational wave engenders.

Collapsing orbiting black holes managed to dispose of 3 solar masses in a very short time with an incredible amount of accompanying sturm und drang as Einsteins equation of mass and energy was demonstrated.....the result of that was a sudden change in gravity.....if you were outside the blast and radiation zone ....I doubt very much you would "notice" a gravitational wave of exceedingly short duration moving at the speed of light.
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