taeto Posted April 12, 2020 Share Posted April 12, 2020 On 4/11/2020 at 3:00 AM, Bmpbmp1975 said: Oh you don’t mean the void you mean where we are. Sorry misunderstood but there is no proof this ever happens and no reason to believe it could right? So far as I can see, this whole thing is very hypothetical, and there is no proof that it ever happened anywhere, nor that it will happen. But of course, if it could happen, then it is reasonable to expect that it could happen anywhere with equal chance, including where we are. Of course that would seem extremely unlikely. Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 12, 2020 Author Share Posted April 12, 2020 (edited) 55 minutes ago, taeto said: So far as I can see, this whole thing is very hypothetical, and there is no proof that it ever happened anywhere, nor that it will happen. But of course, if it could happen, then it is reasonable to expect that it could happen anywhere with equal chance, including where we are. Of course that would seem extremely unlikely. So I was right thank you,this is a non issue I think I am finally learning a little Now if I understand correctly these voids either regular or supervoid are areas in the cosmos that not many galaxies and allot of empty space. Also these areas are colder than other areas around it with more galaxies. but the coldness is not a big difference that the coldness of the universe around it.Am I correct so far. Question: are these voids newish or have they existed for a long time meaning are they forming now or have always been there? Edited April 12, 2020 by Bmpbmp1975 1 Link to comment Share on other sites More sharing options...
Strange Posted April 13, 2020 Share Posted April 13, 2020 19 hours ago, Bmpbmp1975 said: Question: are these voids newish or have they existed for a long time meaning are they forming now or have always been there? The formed very early in the universe. The large scale structure of the universe (walls, filaments, nodes, and voids) were formed by the action of gravity, from the small variations in density in the universe that originally came from quantum fluctuations in the initial hot dense state. So in a sense, they have always been there. Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 4 minutes ago, dimreepr said: No more than entropy is... How new is entropy? Link to comment Share on other sites More sharing options...
Strange Posted April 13, 2020 Share Posted April 13, 2020 24 minutes ago, Bmpbmp1975 said: how about temp difference The cosmic background (CMB) appears cooler where voids are because the light has not passed through as much matter. The difference is tiny; just a few thousandths of a degree. 1 Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 8 minutes ago, Strange said: Ignore it. It is irrelevant. Why is it irrelevant? This has to do with the voids and coldness of the universe. Which is part of the subject. How does entropy ply into this I thought entropy has to do with heat death? Link to comment Share on other sites More sharing options...
Strange Posted April 13, 2020 Share Posted April 13, 2020 Just now, Bmpbmp1975 said: Why is it irrelevant? This has to do with the voids and coldness of the universe. Which is part of the subject. How does entropy ply into this I thought entropy has to do with heat death? Entropy is irrelevant. Dimreeper was just trolling again. Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 (edited) 33 minutes ago, Strange said: Entropy is irrelevant. Dimreeper was just trolling again. Not sure if that entropy deals with temperature of the universe which has to do with the voids. it also deals with heatdeath, so is that what’s happening the voids are the beginning of heat death since they are newly formed objects, I think that’s what dim was implying If the cosmological constantis zero, the universe will approach absolute zerotemperature over a very long timescale. However, if the cosmological constant is positive, as appears to be the case in recent observations, the temperature will asymptote to a non-zero positive value, and the universe will approach a state of maximum entropy in which no further work is possible.[9] so we are positive does positive not mean a true vacuum state? well that’s my understanding from what I read Edited April 13, 2020 by Bmpbmp1975 Link to comment Share on other sites More sharing options...
MigL Posted April 13, 2020 Share Posted April 13, 2020 The temperature of the 'cold spot' or any part of the CMB, is only distantly related ( temporally ) to the density of matter in that area. Recall that the CMB is a 'snapshot' of the temperature of the universe at the time of recombination, when the universe was 300 000 yrs new; when electrons were finally able to stick to nuclei, at about 3000 deg K. If this temperature can be assumed to be nearly isotropic and homogenous, then as the universe expanded some 1040 times over the last 13.8 billion years, any variations in temperature would have become evident over the years. The fact that the CMB has a present variation of 2 parts in 10 000 of the average 2.7 deg K, shows exactly how small the original variations, and the fluctuations that led to them, were. Voids, having less gravitating masses to 'bind' them, had less of a mitigating effect on expansion, and present day voids may be even larger than one would expect from the CMB temperature variation. Link to comment Share on other sites More sharing options...
Strange Posted April 13, 2020 Share Posted April 13, 2020 1 hour ago, Bmpbmp1975 said: Not sure if that entropy deals with temperature of the universe which has to do with the voids. it also deals with heatdeath, so is that what’s happening the voids are the beginning of heat death since they are newly formed objects, I think that’s what dim was implying If the cosmological constantis zero, the universe will approach absolute zerotemperature over a very long timescale. However, if the cosmological constant is positive, as appears to be the case in recent observations, the temperature will asymptote to a non-zero positive value, and the universe will approach a state of maximum entropy in which no further work is possible.[9] so we are positive does positive not mean a true vacuum state? well that’s my understanding from what I read And that has nothing to do with the subject of this thread. Link to comment Share on other sites More sharing options...
MigL Posted April 13, 2020 Share Posted April 13, 2020 1 hour ago, Bmpbmp1975 said: If the cosmological constantis zero, the universe will approach absolute zerotemperature over a very long timescale. However, if the cosmological constant is positive, as appears to be the case in recent observations, the temperature will asymptote to a non-zero positive value, and the universe will approach a state of maximum entropy in which no further work is possible.[9] so we are positive does positive not mean a true vacuum state? A positive Cosmological Constant ( above a threshold value ) simply means that expansion is accelerating, and we will reach maximal entropy sooner than if the CC was a lesser value. And no, it won't happen anytime soon. The fact that expansion is accelerating, COULD mean that we are still in a 'slow roll' from a false vacuum state, to a lower false vacuum state, or the true vacuum state. Or it could not; that's why we call it 'dark' energy. Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 3 minutes ago, MigL said: A positive Cosmological Constant ( above a threshold value ) simply means that expansion is accelerating, and we will reach maximal entropy sooner than if the CC was a lesser value. And no, it won't happen anytime soon. The fact that expansion is accelerating, COULD mean that we are still in a 'slow roll' from a false vacuum state, to a lower false vacuum state, or the true vacuum state. Or it could not; that's why we call it 'dark' energy. So your saying we can turn to a true vaccum state soon Link to comment Share on other sites More sharing options...
Strange Posted April 13, 2020 Share Posted April 13, 2020 2 minutes ago, Bmpbmp1975 said: So your saying we can turn to a true vaccum state soon NO. NO NO NO NO NO STOP IT. NO ONE HAS SAID THAT. Sheesh. Grow up. Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 1 minute ago, Strange said: NO. NO NO NO NO NO STOP IT. NO ONE HAS SAID THAT. Sheesh. Grow up. I was just trying to interpret this comment The fact that expansion is accelerating, COULD mean that we are still in a 'slow roll' from a false vacuum state, to a lower false vacuum state, or the true vacuum state. Or it could not; that's why we call it 'dark' energy. Link to comment Share on other sites More sharing options...
MigL Posted April 13, 2020 Share Posted April 13, 2020 (edited) 9 minutes ago, Bmpbmp1975 said: So your saying we can turn to a true vaccum state soon That is not what I said. 12 minutes ago, MigL said: And no, it won't happen anytime soon. NOT anytime soon. 12 minutes ago, MigL said: to a lower false vacuum state, or the true vacuum state One OR the other, just like always ( IF we are still in the slow roll phase ) Edited April 13, 2020 by MigL Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 Thank you Link to comment Share on other sites More sharing options...
Strange Posted April 13, 2020 Share Posted April 13, 2020 3 minutes ago, Bmpbmp1975 said: I was just trying to interpret this comment "Would you like a cup of tea, I just made it?" "Are you saying the world is going to end!!!" Just stop. 1 Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 2 minutes ago, Strange said: "Would you like a cup of tea, I just made it?" "Are you saying the world is going to end!!!" Just stop. I am sorry I thought that the cosmo constant was always negative and I just found out it’s positive Link to comment Share on other sites More sharing options...
MigL Posted April 13, 2020 Share Posted April 13, 2020 Wow, it's like walking on eggshells around here. You really have to be careful what you say. ( no matter how many ifs, coulds, mays, etc. you put in there ) Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 Just now, MigL said: Wow, it's like walking on eggshells around here. You really have to be careful what you say. ( no matter how many ifs, coulds, mays, etc. you put in there ) I miss read your comment I am sorry , I have been trying a lot harder lately. As I said above thought that the cosmo constant was always negative and I just found out it’s positive or has it always been positive Link to comment Share on other sites More sharing options...
MigL Posted April 13, 2020 Share Posted April 13, 2020 1 minute ago, Bmpbmp1975 said: As I said above thought that the cosmo constant was always negative Since you've taken a liking to reading scientific papers... https://cds.cern.ch/record/485959/files/0102033.pdf It talks about the Cosmo Constant "In this paper it is shown that the recently suggested cosmological model [14] predicts the value = 2:036 10−35s−2 for the cosmological constant. This value of is in excellent agreement with the measurements recently ob- tained by the High-Z Supernova Team and the Supernova Cosmological Project" Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 8 minutes ago, MigL said: Since you've taken a liking to reading scientific papers... https://cds.cern.ch/record/485959/files/0102033.pdf It talks about the Cosmo Constant "In this paper it is shown that the recently suggested cosmological model [14] predicts the value = 2:036 10−35s−2 for the cosmological constant. This value of is in excellent agreement with the measurements recently ob- tained by the High-Z Supernova Team and the Supernova Cosmological Project" I have seen that paper before that paper states constant is positive. My question is has it always been positive or has it switched from negative to positive? Link to comment Share on other sites More sharing options...
MigL Posted April 13, 2020 Share Posted April 13, 2020 The Cosmological Constant was 'added' by A Einstein to the gravitational field equations to counteract gravity and keep the universe stable ( not expanding/not collapsing ); and it was to be determined experimentally. As a positive constant results in ( accelerating ? ) expansion, then a negative constant would add to gravity and result in contraction or collapse ( depending on the value ). When do you think that's happened ??? Link to comment Share on other sites More sharing options...
Bmpbmp1975 Posted April 13, 2020 Author Share Posted April 13, 2020 1 minute ago, MigL said: The Cosmological Constant was 'added' by A Einstein to the gravitational field equations to counteract gravity and keep the universe stable ( not expanding/not collapsing ); and it was to be determined experimentally. As a positive constant results in ( accelerating ? ) expansion, then a negative constant would add to gravity and result in contraction or collapse ( depending on the value ). When do you think that's happened ??? When do I think what happened Link to comment Share on other sites More sharing options...
MigL Posted April 13, 2020 Share Posted April 13, 2020 When do you think contraction or collapse has happened ? Ever ? You really have to work on your reading comprehension... Link to comment Share on other sites More sharing options...
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