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There's a May 2009 clarification request by User Cesiumfrog in the 'Astrophysics and Gravitational section'. It was discussed at the time in 2 sections above (now archived to here and here) by 2 users (both now banned), but not fixed. As we are expecting that this article will need to be cleaned up for ITN purposes by Thursday, I've left a request on Cesiumfrog's Talk page asking him/her to give more detail about what it is that he/she wants clarified. Tlhslobus ( talk) 20:57, 9 February 2016 (UTC)
If we continue to get no details from Cesiumfrog, does anybody know what to do about this (I don't)? Tlhslobus ( talk) 03:27, 11 February 2016 (UTC)
I don't understand the reasoning behind this statement, "The Earth will break apart from tidal forces if it orbits closer than a few radii from the Sun. This would form a ring around the Sun and instantly stop the emission of gravitational waves", specifically the word "instantly". Is there some theoretical lower limit of a mass, below which gravitational waves are not emanated when it moves? Just because the hypothetical Earth in this situation has broken up, does not mean its mass has vanished. Certainly, waves from each of the individual post-breakup particles will carry far less energy than did the whole Earth. Also, because of the roughly circular distribution of the particles and their proximity to one another, the waves will tend to merge and cancel, thus making their detection from a significant distance much more challenging. But the total mass and average orbital speed of particles proximately post-breakup will be the same as the Earth had immediately prior to the breakup, so should the total amount of energy being gravitationally radiated away not also be the same? 108.13.99.101 ( talk) 23:16, 10 February 2016 (UTC)
The 'To do list' currently at the top of this page was created sometime in 2005, and has seemingly not been changed since, even tho many, most, or all the items on it have probably been adequately addressed. So can somebody who understands this subject and/or our ITN quality standards a lot better than me please either update it or delete it - otherwise it's liable to be a source of misdirected effort and/or a cause of unnecessary delay in getting this item posted to ITN if and when the rumoured announcement later today leads to an ITN posting request. Tlhslobus ( talk) 03:47, 11 February 2016 (UTC)
I've now added a warning to this effect at the bottom of the list and also as near the top as I could manage. (If at first you can't see the warnings you may have to click on the 'refresh' command at the top of the list.) Tlhslobus ( talk) 04:32, 11 February 2016 (UTC)
Here is the report on today's announcement: http://www.nsf.gov/news/news_summ.jsp?cntn_id=137628 100.15.120.162 ( talk) 16:18, 11 February 2016 (UTC)
References 1, 7, 57 and 58 should probably be removed, and replaced by reference 8 (the discovery PRL paper) plus a pointer to the LIGO 'Scientific Summary' (semi-technical account) at https://www.ligo.caltech.edu/system/media_files/binaries/301/original/detection-science-summary.pdf ... and the surrounding text adjusted in each case. NormanGray ( talk) 17:28, 11 February 2016 (UTC)
Aaarg! Sorry, I've messed up the reference to the LIGO article, not sure exactly how. I moved the 2016 LIGO detection text to the rear of the section from the front. The reason being it seemed not to be consistent in date order. 80.189.172.184 ( talk) 18:26, 11 February 2016 (UTC)
Isn't is great that gravitational waves were detected exactly one hundred years from when Einstein predicted them in 1916? Titus III ( talk) 23:49, 11 February 2016 (UTC)
Pages are being updated pretty rapidly, but these are pages that still may need to be updated due to the recent news:
If a page doesn't need any changes, or if the needed changes are made, please feel free to edit my comment to cross that page off. Cheers, -- Hirsutism ( talk) 18:29, 11 February 2016 (UTC)
Now that it is in the news, I looked at this page and was surprised that it does not refer to the key item from 1959 on plane solutions [1] . I will not meddle with this page, but whoever likes to, please update with some history. Robinson is still alive, and is probably drinking and celebrating right now. Gravity, gravy, etc. ( talk) 19:36, 11 February 2016 (UTC)
I am puzzled by the use of the word prediction in the article to talk about Albert Einstein's theory. According to Merriam-Webster's definition of the word prediction it is "a statement about what will happen or might happen in the future" or "the act of saying what will happen in the future". Einstein did not say that Gravitational Waves would exist or be found in the future. He theorized about them which according to Merriam-Webster's definition of the word theorize which means "to think of or suggest ideas about what is possibly true or real" I think it would be much more accurate in describing Einstein role in the existence of Gravitational Waves. He understood them and explained them, he didn't say "in a future time scientists will find Gravitational Waves". — Preceding unsigned comment added by 151.33.78.149 ( talk) 09:55, 12 February 2016 (UTC)
The article doesn't talk about gravitons. I'm curious if LIGO measuring these gravity waves, connected to general relativity, can tell us anything about quantum theory? Tom Ruen ( talk) 14:41, 12 February 2016 (UTC)
The section of the article titled "Effects of passing" states:.
The effects of a passing gravitational wave can be visualized by imagining a perfectly flat region of spacetime with a group of motionless test particles lying in a plane (e.g′., the surface of a computer screen)." This description is ignorant of Relativity. A 2D space-time diagram has one axis for space and one axis for time, so particles can only be shown in a straight line, not a ring as is being discussed in that section. The diagram also has no time axis. The author seems to think that space-time is just a fancy way of saying "space". 1.75.240.2 ( talk) 09:06, 13 February 2016 (UTC)
Can anyone explain this animation [3] from space.com, showing two orbital black holes, and a rainbow colored stretched surface below, which bends downwards for mass, but after 0:40 it bents upwards on the orthogonal directions of the black holes. Is the bending upwards implying some sort of "spacial contraction" (versus ordinary gravity expansion of space, slowing of time) or otherwise a "repulsive gravity force" (like the traditional tabletop model of gravity on a curved surface) or something else? What is gravity doing in those "upward" domains? Tom Ruen ( talk) 17:02, 13 February 2016 (UTC)
I realized the gravitational waves could be longitudinal wave (like sound), or transverse wave (like light), or could be both! I'd assume gravitational waves are more like sound, with space-time compression/distortions, but this article talks about polarization, which suggests transverse waves. It seems like this wave-nature is something that can be clarified in this article. Tom Ruen ( talk) 00:42, 17 February 2016 (UTC)
FT2 ( Talk | email) 10:38, 17 February 2016 (UTC)
From the Wikipedia pages we find that: 1. “ Systems that have nonzero energy but zero rest mass, such as photons moving in a single direction, do not have ‘center-of-mass’ frames, because there is no frame in which they have zero net momentum. They always possess a net momentum magnitude that is equal to their energy divided by the speed of light. 2. The angular momentum of light is a vector quantity that expresses the amount of dynamical rotation present in the electromagnetic field of the light. Indeed, a beam of light, while traveling approximately in a straight line, can also be rotating (or “spinning”, or “twisting”) around its own axis. This rotation, while not visible to the naked eye, can be revealed by the interaction of the light beam with matter, as shown in the figure below: The total angular momentum of light and matter is conserved in time. But there are actually two distinct forms of rotation of a light beam, one involving its polarization and the other its wave-front shape. These two forms of rotation are hence associated with two distinct forms of angular momentum, respectively named (i) light spin angular momentum (SAM) and (ii) light orbital angular momentum (OAM).” From the above statements it appears that a photon moving in straight line with an orbital angular momentum, as shown in a picture in the Wikipedia page, is likely to radiate gravitational waves. What is the opinion of the expert editors? Question from: Hasmukh K. Tank 117.228.140.245 ( talk) 15:46, 24 February 2016 (UTC)
Dear Friend, Please find the references. Based on the references we can understand and partly explain the 'cosmological red-shift' in terms of extra galactic light loosing energy because of gravitational waves radiation. Hasmukh K. Tank, 117.229.15.132 ( talk) 17:02, 4 April 2016 (UTC)
At present the article reads: "If the dumbbell spins like a wheel on an axle, it will not radiate gravitational waves; if it tumbles end over end, as in the case of two planets orbiting each other, it will radiate gravitational waves. The heavier the dumbbell, and the faster it tumbles, the greater is the gravitational radiation it will give off. In an extreme case, such as when the two weights of the dumbbell are massive stars like neutron stars or black holes, orbiting each other quickly, then significant amounts of gravitational radiation would be given off."
The first line makes little sense: "If the dumbbell spins like a wheel on an axle, it will not radiate gravitational waves; if it tumbles end over end, as in the case of two planets orbiting each other, it will radiate gravitational waves." If the dumbbell spins like a wheel on an axle that is the same like "it tumbles end over end." So, that is not well expressed.
The second part: "The heavier the dumbbell, and the faster it tumbles, the greater is the gravitational radiation it will give off. In an extreme case, such as when the two weights of the dumbbell are massive stars like neutron stars or black holes, orbiting each other quickly, then significant amounts of gravitational radiation would be given off." That implies that simply by tumbling it is somehow radiating energy from some source. What is the source of that energy? I suspect, but am uncertain, that the energy is the result of the change of the potential energy of the two masses as they spiral into each other. If that is not the source of energy then what is it? Mass and energy that enters the critical radius of a black hole is there to stay forever with the exception of the extraction of energy associated with the spin energy of each BH through the Penrose Process. But the Penrose Process is not the source of the gravitational energy and the orbit of the masses about each other does not magically create energy. The only source of energy I see here is due to the decrease of Potential Energy as a result of their spiralling into each other. Potential Energy results in an increase of the kinetic energy of the BH and some of that PE is carried away in the form of gravitational waves. Zedshort ( talk) 14:39, 6 March 2016 (UTC)
I disagree with this revert of my edit. "We must align this article with the electromagnetic radiation article" is not an acceptable reason for a blanket revert, and I disagree with the premise. There is no good reason why the presentation here should align closely with that other article, and even if that were so that would not justify all of the changes that were reverted in this edit.-- Srleffler ( talk) 06:08, 9 March 2016 (UTC)
Gravitational waves because of two black holes merge was detected, but why not being sucked? 星耀晨曦 ( talk) 06:42, 10 March 2016 (UTC)
has given the most axiomatic and complete description of gravitational waves, Annali di Matematica Pura & Appl. 4 [1960] p 1-95 "Ondes et Radiation Électromagnétiques et Gravitationelles en Relativité Générale", although in an old-fashioned way with indices instead of basis-free. It should be included in the bibliography! — Preceding unsigned comment added by 72.77.197.12 ( talk) 14:28, 19 March 2016 (UTC)
No particle is able to travel faster than the speed of light, but usually briefly space chunks themselves at extreme conditions (for example during big bangs or black hole mergers). During the normalization process all quantum information is emitted subluminally (under the light-speed limit) but biased polarization statistics reveal the event.
As far as I can see the following reference is omitted:
Also the reference to Einstein 1918 is repeated as refs 3 and 32. I would make the changes myself but how to do it? JFB80 ( talk) 13:37, 13 May 2016 (UTC)
So I came across this paper claiming that the upper limit on gravitational wave propagation is 1.7c. http://arxiv.org/abs/1602.04188 Does anyone know if there is a critique or rebuttal to this paper anywhere, or could someone tell me how this paper is wrong? Thanks. — Preceding unsigned comment added by 96.50.27.58 ( talk) 01:53, 25 June 2016 (UTC)
Nothing wrong with the paper as far as I can see. It just states direct experimental upper limits on speed of gravitational wave propagation, assuming no underlying models with Lorentz symmetry and come up with 1.7c. In models with Lorentz symmetry we have c as the universal speed limit of course. — Preceding unsigned comment added by Sharanbngr ( talk • contribs) 15:57, 13 September 2016 (UTC)
In 1905 Henri Poincaré first predicted gravitational waves ondes gravifiques emanating from a body and propagating at the speed of light as being required by the formalism of spacetime. [1]
This must be included in this Wikipedia article. — Preceding unsigned comment added by 173.65.234.214 ( talk) 13:22, 30 June 2016 (UTC)
References
That is completely right, but Poincares prediction was in the context of special relativity, since general relativity has not been invented in 1905! — Preceding unsigned comment added by 130.133.155.68 ( talk) 09:31, 2 July 2016 (UTC)
NO, Poincarré is talking about GRAVITY, the propagation of GRAVITY, it's supposed speed of propagation, according to Laplace, etc. He is NOT talking about "gravitationnal waves". Different subjects. In "ondes gravifique" the adjective "gravifique" means "that PRODUCE gravity". Gravitationnal waves don't produce any gravity or gravitationnal effects. They ORIGINATE from a gravitationnal situation i.e. accelerations. The sound of moving leaves in a tree doesn't produce wind. — Preceding unsigned comment added by 163.47.106.116 ( talk) 00:24, 13 January 2017 (UTC)
All matter (atoms, stars etc.) emit gravitational waves (usually undetectably negligible). All stars emit gravitational waves in a galaxy (at much lower levels than a black hole merger event), and that energy is absorbed by other stars more and more in relation to the distance from the galactic core. Of course that idea is moronic, but in Wikipedia we should mention all ideas, if it is silly like that one we should analyze that the provided energy wouldn't be enough. Censorship doesn't help! — Preceding unsigned comment added by 2A02:587:4109:5C00:3102:EF8:C9E5:D035 ( talk) 17:36, 16 September 2016 (UTC)
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | ← | Archive 3 | Archive 4 | Archive 5 |
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | ← | Archive 3 | Archive 4 | Archive 5 |
There's a May 2009 clarification request by User Cesiumfrog in the 'Astrophysics and Gravitational section'. It was discussed at the time in 2 sections above (now archived to here and here) by 2 users (both now banned), but not fixed. As we are expecting that this article will need to be cleaned up for ITN purposes by Thursday, I've left a request on Cesiumfrog's Talk page asking him/her to give more detail about what it is that he/she wants clarified. Tlhslobus ( talk) 20:57, 9 February 2016 (UTC)
If we continue to get no details from Cesiumfrog, does anybody know what to do about this (I don't)? Tlhslobus ( talk) 03:27, 11 February 2016 (UTC)
I don't understand the reasoning behind this statement, "The Earth will break apart from tidal forces if it orbits closer than a few radii from the Sun. This would form a ring around the Sun and instantly stop the emission of gravitational waves", specifically the word "instantly". Is there some theoretical lower limit of a mass, below which gravitational waves are not emanated when it moves? Just because the hypothetical Earth in this situation has broken up, does not mean its mass has vanished. Certainly, waves from each of the individual post-breakup particles will carry far less energy than did the whole Earth. Also, because of the roughly circular distribution of the particles and their proximity to one another, the waves will tend to merge and cancel, thus making their detection from a significant distance much more challenging. But the total mass and average orbital speed of particles proximately post-breakup will be the same as the Earth had immediately prior to the breakup, so should the total amount of energy being gravitationally radiated away not also be the same? 108.13.99.101 ( talk) 23:16, 10 February 2016 (UTC)
The 'To do list' currently at the top of this page was created sometime in 2005, and has seemingly not been changed since, even tho many, most, or all the items on it have probably been adequately addressed. So can somebody who understands this subject and/or our ITN quality standards a lot better than me please either update it or delete it - otherwise it's liable to be a source of misdirected effort and/or a cause of unnecessary delay in getting this item posted to ITN if and when the rumoured announcement later today leads to an ITN posting request. Tlhslobus ( talk) 03:47, 11 February 2016 (UTC)
I've now added a warning to this effect at the bottom of the list and also as near the top as I could manage. (If at first you can't see the warnings you may have to click on the 'refresh' command at the top of the list.) Tlhslobus ( talk) 04:32, 11 February 2016 (UTC)
Here is the report on today's announcement: http://www.nsf.gov/news/news_summ.jsp?cntn_id=137628 100.15.120.162 ( talk) 16:18, 11 February 2016 (UTC)
References 1, 7, 57 and 58 should probably be removed, and replaced by reference 8 (the discovery PRL paper) plus a pointer to the LIGO 'Scientific Summary' (semi-technical account) at https://www.ligo.caltech.edu/system/media_files/binaries/301/original/detection-science-summary.pdf ... and the surrounding text adjusted in each case. NormanGray ( talk) 17:28, 11 February 2016 (UTC)
Aaarg! Sorry, I've messed up the reference to the LIGO article, not sure exactly how. I moved the 2016 LIGO detection text to the rear of the section from the front. The reason being it seemed not to be consistent in date order. 80.189.172.184 ( talk) 18:26, 11 February 2016 (UTC)
Isn't is great that gravitational waves were detected exactly one hundred years from when Einstein predicted them in 1916? Titus III ( talk) 23:49, 11 February 2016 (UTC)
Pages are being updated pretty rapidly, but these are pages that still may need to be updated due to the recent news:
If a page doesn't need any changes, or if the needed changes are made, please feel free to edit my comment to cross that page off. Cheers, -- Hirsutism ( talk) 18:29, 11 February 2016 (UTC)
Now that it is in the news, I looked at this page and was surprised that it does not refer to the key item from 1959 on plane solutions [1] . I will not meddle with this page, but whoever likes to, please update with some history. Robinson is still alive, and is probably drinking and celebrating right now. Gravity, gravy, etc. ( talk) 19:36, 11 February 2016 (UTC)
I am puzzled by the use of the word prediction in the article to talk about Albert Einstein's theory. According to Merriam-Webster's definition of the word prediction it is "a statement about what will happen or might happen in the future" or "the act of saying what will happen in the future". Einstein did not say that Gravitational Waves would exist or be found in the future. He theorized about them which according to Merriam-Webster's definition of the word theorize which means "to think of or suggest ideas about what is possibly true or real" I think it would be much more accurate in describing Einstein role in the existence of Gravitational Waves. He understood them and explained them, he didn't say "in a future time scientists will find Gravitational Waves". — Preceding unsigned comment added by 151.33.78.149 ( talk) 09:55, 12 February 2016 (UTC)
The article doesn't talk about gravitons. I'm curious if LIGO measuring these gravity waves, connected to general relativity, can tell us anything about quantum theory? Tom Ruen ( talk) 14:41, 12 February 2016 (UTC)
The section of the article titled "Effects of passing" states:.
The effects of a passing gravitational wave can be visualized by imagining a perfectly flat region of spacetime with a group of motionless test particles lying in a plane (e.g′., the surface of a computer screen)." This description is ignorant of Relativity. A 2D space-time diagram has one axis for space and one axis for time, so particles can only be shown in a straight line, not a ring as is being discussed in that section. The diagram also has no time axis. The author seems to think that space-time is just a fancy way of saying "space". 1.75.240.2 ( talk) 09:06, 13 February 2016 (UTC)
Can anyone explain this animation [3] from space.com, showing two orbital black holes, and a rainbow colored stretched surface below, which bends downwards for mass, but after 0:40 it bents upwards on the orthogonal directions of the black holes. Is the bending upwards implying some sort of "spacial contraction" (versus ordinary gravity expansion of space, slowing of time) or otherwise a "repulsive gravity force" (like the traditional tabletop model of gravity on a curved surface) or something else? What is gravity doing in those "upward" domains? Tom Ruen ( talk) 17:02, 13 February 2016 (UTC)
I realized the gravitational waves could be longitudinal wave (like sound), or transverse wave (like light), or could be both! I'd assume gravitational waves are more like sound, with space-time compression/distortions, but this article talks about polarization, which suggests transverse waves. It seems like this wave-nature is something that can be clarified in this article. Tom Ruen ( talk) 00:42, 17 February 2016 (UTC)
FT2 ( Talk | email) 10:38, 17 February 2016 (UTC)
From the Wikipedia pages we find that: 1. “ Systems that have nonzero energy but zero rest mass, such as photons moving in a single direction, do not have ‘center-of-mass’ frames, because there is no frame in which they have zero net momentum. They always possess a net momentum magnitude that is equal to their energy divided by the speed of light. 2. The angular momentum of light is a vector quantity that expresses the amount of dynamical rotation present in the electromagnetic field of the light. Indeed, a beam of light, while traveling approximately in a straight line, can also be rotating (or “spinning”, or “twisting”) around its own axis. This rotation, while not visible to the naked eye, can be revealed by the interaction of the light beam with matter, as shown in the figure below: The total angular momentum of light and matter is conserved in time. But there are actually two distinct forms of rotation of a light beam, one involving its polarization and the other its wave-front shape. These two forms of rotation are hence associated with two distinct forms of angular momentum, respectively named (i) light spin angular momentum (SAM) and (ii) light orbital angular momentum (OAM).” From the above statements it appears that a photon moving in straight line with an orbital angular momentum, as shown in a picture in the Wikipedia page, is likely to radiate gravitational waves. What is the opinion of the expert editors? Question from: Hasmukh K. Tank 117.228.140.245 ( talk) 15:46, 24 February 2016 (UTC)
Dear Friend, Please find the references. Based on the references we can understand and partly explain the 'cosmological red-shift' in terms of extra galactic light loosing energy because of gravitational waves radiation. Hasmukh K. Tank, 117.229.15.132 ( talk) 17:02, 4 April 2016 (UTC)
At present the article reads: "If the dumbbell spins like a wheel on an axle, it will not radiate gravitational waves; if it tumbles end over end, as in the case of two planets orbiting each other, it will radiate gravitational waves. The heavier the dumbbell, and the faster it tumbles, the greater is the gravitational radiation it will give off. In an extreme case, such as when the two weights of the dumbbell are massive stars like neutron stars or black holes, orbiting each other quickly, then significant amounts of gravitational radiation would be given off."
The first line makes little sense: "If the dumbbell spins like a wheel on an axle, it will not radiate gravitational waves; if it tumbles end over end, as in the case of two planets orbiting each other, it will radiate gravitational waves." If the dumbbell spins like a wheel on an axle that is the same like "it tumbles end over end." So, that is not well expressed.
The second part: "The heavier the dumbbell, and the faster it tumbles, the greater is the gravitational radiation it will give off. In an extreme case, such as when the two weights of the dumbbell are massive stars like neutron stars or black holes, orbiting each other quickly, then significant amounts of gravitational radiation would be given off." That implies that simply by tumbling it is somehow radiating energy from some source. What is the source of that energy? I suspect, but am uncertain, that the energy is the result of the change of the potential energy of the two masses as they spiral into each other. If that is not the source of energy then what is it? Mass and energy that enters the critical radius of a black hole is there to stay forever with the exception of the extraction of energy associated with the spin energy of each BH through the Penrose Process. But the Penrose Process is not the source of the gravitational energy and the orbit of the masses about each other does not magically create energy. The only source of energy I see here is due to the decrease of Potential Energy as a result of their spiralling into each other. Potential Energy results in an increase of the kinetic energy of the BH and some of that PE is carried away in the form of gravitational waves. Zedshort ( talk) 14:39, 6 March 2016 (UTC)
I disagree with this revert of my edit. "We must align this article with the electromagnetic radiation article" is not an acceptable reason for a blanket revert, and I disagree with the premise. There is no good reason why the presentation here should align closely with that other article, and even if that were so that would not justify all of the changes that were reverted in this edit.-- Srleffler ( talk) 06:08, 9 March 2016 (UTC)
Gravitational waves because of two black holes merge was detected, but why not being sucked? 星耀晨曦 ( talk) 06:42, 10 March 2016 (UTC)
has given the most axiomatic and complete description of gravitational waves, Annali di Matematica Pura & Appl. 4 [1960] p 1-95 "Ondes et Radiation Électromagnétiques et Gravitationelles en Relativité Générale", although in an old-fashioned way with indices instead of basis-free. It should be included in the bibliography! — Preceding unsigned comment added by 72.77.197.12 ( talk) 14:28, 19 March 2016 (UTC)
No particle is able to travel faster than the speed of light, but usually briefly space chunks themselves at extreme conditions (for example during big bangs or black hole mergers). During the normalization process all quantum information is emitted subluminally (under the light-speed limit) but biased polarization statistics reveal the event.
As far as I can see the following reference is omitted:
Also the reference to Einstein 1918 is repeated as refs 3 and 32. I would make the changes myself but how to do it? JFB80 ( talk) 13:37, 13 May 2016 (UTC)
So I came across this paper claiming that the upper limit on gravitational wave propagation is 1.7c. http://arxiv.org/abs/1602.04188 Does anyone know if there is a critique or rebuttal to this paper anywhere, or could someone tell me how this paper is wrong? Thanks. — Preceding unsigned comment added by 96.50.27.58 ( talk) 01:53, 25 June 2016 (UTC)
Nothing wrong with the paper as far as I can see. It just states direct experimental upper limits on speed of gravitational wave propagation, assuming no underlying models with Lorentz symmetry and come up with 1.7c. In models with Lorentz symmetry we have c as the universal speed limit of course. — Preceding unsigned comment added by Sharanbngr ( talk • contribs) 15:57, 13 September 2016 (UTC)
In 1905 Henri Poincaré first predicted gravitational waves ondes gravifiques emanating from a body and propagating at the speed of light as being required by the formalism of spacetime. [1]
This must be included in this Wikipedia article. — Preceding unsigned comment added by 173.65.234.214 ( talk) 13:22, 30 June 2016 (UTC)
References
That is completely right, but Poincares prediction was in the context of special relativity, since general relativity has not been invented in 1905! — Preceding unsigned comment added by 130.133.155.68 ( talk) 09:31, 2 July 2016 (UTC)
NO, Poincarré is talking about GRAVITY, the propagation of GRAVITY, it's supposed speed of propagation, according to Laplace, etc. He is NOT talking about "gravitationnal waves". Different subjects. In "ondes gravifique" the adjective "gravifique" means "that PRODUCE gravity". Gravitationnal waves don't produce any gravity or gravitationnal effects. They ORIGINATE from a gravitationnal situation i.e. accelerations. The sound of moving leaves in a tree doesn't produce wind. — Preceding unsigned comment added by 163.47.106.116 ( talk) 00:24, 13 January 2017 (UTC)
All matter (atoms, stars etc.) emit gravitational waves (usually undetectably negligible). All stars emit gravitational waves in a galaxy (at much lower levels than a black hole merger event), and that energy is absorbed by other stars more and more in relation to the distance from the galactic core. Of course that idea is moronic, but in Wikipedia we should mention all ideas, if it is silly like that one we should analyze that the provided energy wouldn't be enough. Censorship doesn't help! — Preceding unsigned comment added by 2A02:587:4109:5C00:3102:EF8:C9E5:D035 ( talk) 17:36, 16 September 2016 (UTC)
![]() | This is an archive of past discussions. Do not edit the contents of this page. If you wish to start a new discussion or revive an old one, please do so on the current talk page. |
Archive 1 | ← | Archive 3 | Archive 4 | Archive 5 |