Robittybob1
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What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
Why do you bring nuclear binding energy to a discussion on gravity? The free neutrons have more energy /mass than if they were bound but they don't just get attracted together by gravity and then lose this binding energy and fuse together. So how close can two neutrons be naturally without being forced together. In that experiment they seem to have neutrons going into their device and they are observed to fall in stages. Is that the Earth's gravity pulling them down in quanta? http://arxiv.org/pdf/hep-ph/0306198.pdf I'll reread the paper but I need a bit more understanding to start comprehending it. -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
I think one of the best explanations for the difference between relativity (GR) and Newtonian gravity is the following paragraph from the paper: I was surprised by this statement: I wonder when they can tell when the signal first arrived? For when I put a ruler across the tops of the waves the Hanford strain trace lasts longer than the Livingston one yet the peaks seem to be earlier in the Hanford site at the beginning of the signal. This might be part of the issue with superimposing wave signals as I was explaining in #66, where in different regions of space the signals will form nodes and others regions not as much. This suggests a more top/bottom or even an intermediary line of sight rather than a true side on view. The time domain data covers a period of just over 0.2 seconds. The observed time delay 6.9 ms: Are they saying the signal arrived in Livingston first? Are they using the largest peak to take these times from? How can they pick up when the signal started when the reading is virtually flat? . -
What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
"1 joule is equal to 1.0E+12 picojoule" So pico is much smaller than Peta! I've never used these descriptions before. Thanks -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
http://arxiv.org/pdf/1602.03840v1.pdf "The posterior PDF shows that an orientation of the total orbital angular momentum of the BBH strongly misaligned to the line of sight is disfavoured; the probability that 45◦ < θJN < 135◦ is 0.35." Orbital angular momentum is orthogonal to the orbital plane is that correct? So they say the chances (probability) of it being a side on view are not favoured. For the angles of total angular momentum as the range only occur with a somewhat side on view. Is that the correct interpretation of that sentence from the paper? @Strange - Reading your post we are now on the same page as they say. When they give the outcome in a measure of probability one can't rule out the opposite being true in some cases. There are some nice traces of the LIGO detection, very spread out Fig 6 page 10/19. "So 30 degrees off perpendicular to the plane." Do you mean "the orbital plane was 60 degrees to the line of sight" That could mean we are looking at it from underneath in a manner of speaking. -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
This is interesting So if there is any connection to how GW work the passing GW would not change strength but only direction and that would make my statement quoted in #61 possibly true. I think time will tell. Let's take a break. I'm also going to take a break and step away for a while. -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
Very good observations thanks Imatfaal. Can anyone explain what polarisation means in this context? Is that the degrees of motion (directions) to which the test particles would move when the wave passed? "circularly polarized" "Linearly polarized" -
What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
size of the units. so that is 10 to the power of -3, 3,6,9,12,15, and 18 respectively. They are 8.0E-16 m but they need to be in the order of 8.0E-18 m apart to have a PeV of gravitational potential. OK I might have a better understanding of the experiment now. 2.93E-34 Joules is something else. absolute gravitational potential = Gm/(r^2) for a neutron = 1.75E-07 J/kg "At least 12 frikkin' orders of magnitude smaller than the nuclear binding energy." -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
General relativity is used, I agree, but once the waves are in space traveling at the speed of light why can't we revert to general physics after that? If for some reason the spacial arrangement of the Gwaves were not isotropic around the BH then my model would definitely fail. If it was possible to measure GE directly would any part of the BH be producing more energy at the level of the event horizon than at any other point? Or would it be like polar jets of GE? This would be an extreme example image https://upload.wikimedia.org/wikipedia/commons/thumb/f/f8/Galaxies-AGN-Inner-Structure.svg/270px-Galaxies-AGN-Inner-Structure.svg.png -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
My model could be wrong and that statement I made earlier could be wrong (contained in #61) but I have thought the problem through since and on the basis of Gwaves being produced continuously and the way waves would superimpose. So my best shot at understanding how the physics is predicted to work was in #62 http://www.scienceforums.net/topic/93875-warped-spacetime-around-bh-and-the-barycenter/page-4#entry910990 You can either agree or disagree. The exact answer to the question you've asked may not have yet been resolved. I don't know of any papers covering that particular question. Katie Mack needs to give her reasons then for saying what she did in that tweet. This is my best shot: "So you will get nodes (above and below the orbital plane) where the waves are superimposed (nodes) and the nodes will travel, but the frequency (at the nodes) is halved and the intensity is doubled (2 waves merged into one) so the amount of GE is still the same (passing through a detector in line of sight) over time. But because the orbital radius is changing rapidly and erratically in most cases where the masses are unequal these nodes also will be occurring in different positions (in space) every orbit." Above and below the orbital plane is it true there will never be superposition of the G-wave from the one BH as it orbits? I'm thinking the waves will always be far enough apart that no position of line of sight will allow a wave from a previous orbit to be superimposed on a subsequent one, no matter from which part of the orbit it originated. Does this logic hold true? -
What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
Are you working with different radii than in Wikipedia? 0.8 X 10-15 m is the same as 8.0E-16 isn't it? So that force was when the two neutons were theoretically touching. Is this not possible? What radius are you using please? -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
Please, how do you define orbital plane? Define the angle of inclination of the orbital plane to the line of sight. -
What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
Newtons sorry -
"TEDxBoulder - Thad Roberts - Visualizing Eleven Dimensions" was a help to me understanding the other dimensions. It was just a talk though. But there were terms in there that would help with other searches.
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What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
I looked up Neutron radius yesterday and they gave it as 8.00E-16 meters so that is quite close to "~10^-18 m". The experiment is then in the lab rather than in space. From that and the mass I worked out the G force between two protons was 2.93E-34 Newtons [Edit: not Joules.] -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
Show me where it says that please? Define orbital plane as you use it please? Here is my definition from Wikipedia "In the Solar System, the inclination of the orbit of a planet is defined as the angle between the plane of the orbit of the planet and the ecliptic.[2] Therefore Earth's inclination is, by definition, zero." Would references to the way waves superimpose help then? For to me the same physics would apply. Wave tank experiments showing where the waves increase in intensity? Its been awhile since I've seen those experiments. This experiment would be similar to how I predict GWaves would spread out through space "Physics Lab Demo 14: Ripple Tank" that is a YT demonstration done by a teacher. What we'd really need is a ripple tank with the two points rotating (constantly in the water). Even that will only produces waves on the plane of orbit (Orbital plane) Can you think how you could set up a wave tank that would show the waves above and below the orbital plane. If you had a large deep tank and had 2 masses orbiting slowly deep under the water I wonder if the waves would appear on the surface? This is not the usual wave tank setup. We would not want any reflection from the sides of the tank for we are not going to get reflection of GWaves. In fact that would start the water rotating along with the masses causing the waves. so after a while you would get no waves or at least less waves being generated. I can't think how you could physically demonstrate 3D waves being generated by a quadrupole. -
What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
I found the abstract only at this stage but it sounds really important, I wonder if it has gained acceptance? http://www.nature.com/nature/journal/v415/n6869/full/415297a.html The number of neutrons and mass would be highly correlated wouldn't it? So in the above abstract was the neutron falling from one height to the other the action of a quanta? A quanta of what? Energy? Is that a change in its mass? Nesvizhevsky is on YT. found a paper: http://arxiv.org/pdf/hep-ph/0306198.pdf "Measurement of quantum states of neutrons in the Earth’s gravitational field" @John - Do you understand what that paper is about? -
What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
Force came out to 2.93E-34 Newtons. If they were gravitationally bound could we use another force to move them to confirm they were bound? Unbound ones should be easier to move, is that right? -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
Are you willing to look at wave patterns on diagrams/animations? This was from my own analysis so it is another of the predictions. I could see what @AstroKatie (Katie Mack, an astrophysicist) was talking about but the effect was sporadic and only stronger quite close to the merging BHs from studying the animation. This occurred where the two waves added together (superimposed) and the frequency in effect was halved. The waves were approaching each other at an angle (around 60 - 120 degrees) so they don't travel in that strong phase as they will pass through that point of superposition. Do you want another YT video linked to the thread? I'll find it but it is complex in the extreme. You'll need to view it. I brought the speed down to 0.25 and the best view was 10 secs into the animation. Maybe it's not the one I saw yesterday but it is close. At about 8 - 10 secs into it the waves superimpose directly above the orbital plane. The animation makes it look like that the gravitational waves are pulsations from the surface of the BH. The whole animation could be wrong. I am tending to think it is more an artefact rather than real for if the GW is coming continuously of the body as it is accelerating continuously in orbit there is a spot which is equidistant from both of the orbiting BHs At these spots the GW superimpose and the intensity will be high but more or less continuous or at least slower in frequency and hence harder to pick up. I'm in two minds over this one. It is much harder to think through. Would I be right in thinking a strong low frequency GW is going to be more difficult to pick up. (Compared to the "chirp") To have the waves as close as this animation the BHs would need to going faster than the speed of light. If the circumference of the orbit is 2 * pi() * r and they are going at 0.5c the radiation from each body should be 4 * pi() * r apart (the wave per each should be twice the orbital circumference away from the BH it emanates from) or every wave (that is from the 2 bodies in the binary) should be at about 2 * pi() * r apart radiating from each BH of an equal mass BBH going at 0.5c. At 0.5c the waves should be around 12.6 times the orbital radius apart from its particular source. So you will get nodes where the waves are superimposed and the nodes will travel, but the frequency is halved and the intensity is doubled (2 waves merged into one) so the amount of GW is still the same over time. But because the orbital radius is changing rapidly and erratically in most cases where the masses are unequal these nodes also will be occurring in different positions every orbit. If you had a series of GW waves at these nodes and were being picked up by LIGO I wonder how they would distinguish them from the same frequency waves but coming from the orbital plane? I would predict (from the above considerations) the chances of getting the chirp exactly dead center from equal mass BBHs is going to be very rare. -
What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
Individual Neutrons. it seems like you can have a very dense object quite close to another F = G m^2 / ( r^2 ). R^2 would be a very small number so can the force be measured? -
What is the smallest mass proven to have gravity?
Robittybob1 replied to Robittybob1's topic in Classical Physics
can we see gravitational attraction between two neutrons as between two neutron stars? Would they tend to clump together? Would we have a problem of getting rid of their gravitational potential energy? -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
We have the orbital plane (OP) that extends indefinitely. that could be like the x axis. and we have the Earth defining the line of sight back to the BBHs. The line of sight meets the orbital plane at an angle Theta. The distance along the line of sight becomes the hypotenuse of a right angle triangle. If each of the BHs produce a wave and they are at opposite sides of the binary orbit and the BHs have a different mass their orbital radii will be related by the barycenter calculation, the length of the hypotenuse changes depending whether you are closest to the inner or outer BH. If the orbit is divided perpendicular to the line of sight,in each half orbit period this will change. In one half M1 is closest then the next half orbital period M2 will be closest Let r be the distance that the BHs are apart Let M1 be the mass of the lighter BH Let M2 be the mass of the heavier BH Distance to the barycenter for M1 is A1 Distance to the barycenter for M2 is A2 If the barycenter is (0,0) A1 is further from (0,0) than A2 so theta changes whether the wave originated from M1 (theta1 is greater) or M2 (theta2 is lesser). If the wave originated from M1 theta1 is greater. If the wave originated from M2 theta2 is lesser. So the adjacent side (along the x axis) and the hypotenuse changes when you are observing the different BHs Hypotenuse to M1 = H1 Hypotenuse to M2 = H2 From the side of the orbit where the waves that reach the Earth come from: A1 = r * M2 / (M1 + M2) [A1 is longer hence M1 closer to Earth] A2 = r * M1 / (M1 + M2) [A2 is shorter hence M2 further from Earth] So if the length of the adjacent to M1 is X1 the length to M2 is X2 then X2 = X1 + ( A1 - A2 ) [Note: X2 > X1 because A1 > A2] Tan Theta1 = H1 / X1 Tan Theta2 = H2 / X2 [Note: as theta increases the ratio of changes in H1 and H2 become less marked.] The minimum angle could be zero degrees where the difference in H1 and H2 will be most marked, hence the time to travel to Earth will cause the waves to bunch in groups of two. This bunching is also noted when the masses of the BH are markedly different. The maximum angle to the orbital plane is 90 degrees. At that position the Earth would receive a constant flow of gravitational energy and hence it would not register on the LIGO. There could be angles where the two waves added together and appeared more powerful but then the frequency would be halved as the two waves were added together. (This effect is apparent on some of the simulations, particularly the one showing the 3D nature of the GWs.) So 0 - 30 degrees is somewhat aligned to the orbital plane 60 - 90 degrees could be described as nearly orthogonal to the orbital plane. 30 - 60 degrees neither. -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
As I said before from looking at the delayed wave and advanced wave and thinking about how at a greater the angle these differences in distance would disappear. (Trigonometric considerations) -
Ramifications of electrons not having gravitational mass (split)
Robittybob1 replied to John Cuthber's topic in Speculations
Comparative mass: Proton is 1837 times heavier than an electron. Neutron = 1 Proton = 0.99862349 Electron = 0.00054386734 So for every electron you have a proton and a neutron so the ratio is roughly 1:2*1837 or approx. 0.000272183 Is that the ratio you are using? -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
What form did "the data" have? It was a wave pattern which I'm calling a graph. Graph might not be the right word but it is close. One never knows if you are being ignored or not? "Define "somewhat aligned"." I predict it would have a line of sight that would have been within 30 degrees of the orbital plane (above or below). Animations, simulations, simulated strain graphs that type of data to compare actual data with. That is what they were saying in that recording of the conference at the announcement. -
Warped spacetime around BH and the barycenter
Robittybob1 replied to Robittybob1's topic in Relativity
What does it say about the orbital plane? So does that mean they are saying the orbital plane "probably" aligns with the line of sight? (end of page 6 beginning 7) My prediction was just for the last 3 orbits before the merger. During that time I predict it was aligned with the line of site. OK that is what I meant, they compared the results of animations and simulations to the Interferometer strain readings to predict what sort of BBH situation they were dealing with. I think we are saying the same thing in fact. Some animations could be completed after the recording of the chirp was made too. That doesn't matter in reality but the point is they are comparing computer analyses of hypothetical situations to an actual recording. Is that your understanding too? .