The relation beween black holes and dark matter.

Manafest_Destiny · Jan 14, 2009

In this installment I will address the relationship between dark matter and black holes as theorized by myself. I have had a suprizing amount of feed back regarding this subject, so I have decided to touch base on some of the basic concepts of the theory...  Enjoy!   Ever since Einstein made the world aware of the existance of black holes they have perplexed and fasinated sientists with almost inconcivable ideas of huge masses and distorting space-time. We have almost unanimosly coined them as the devourers of the universe.   Allow us, for a moment, to consider a more Newtonian idea, where light and matter that pass beyond the event horizon are not destroyed, but converted. As matter enters the black hole it is streched, essintialy disintergrting it. Proton and nuetrons are stripped of their electrons as the matter breaks down into an even smaller thread form. Now here comes the fun part. Not only is this trapped light and matter losing substance as it's torn apart at a sub-atomic level, but the distortion of space-time caused by the black hole in addition to the amazing speeds at which the matter..light is moving causes all of this to happen in a nearly timeless enviroment.   This is where our current understanding of mathamatics becomes useless. Because we have no way to see beyond an event horizon, the nessisary variables escape us. Still, it doesn't take much of a stretch to assume that all of that matter..light is not destroyed, simply converted into a form that mirrors the perfect stability of the black hole the spawned it. Naturaly, if black holes create a new material, then the amount of matter consumed by a black hole mutiplied by the enourmous amount of black holes in the universe, would inevitably cause whatever element they created to be the most plentiful matierial in the universe.   Upon searching for an overly ubundant element that was perfectly stable and let off no energy, thus rendering it undetectable by current means, one answer jumped out. Dark matter. Because of the very nature of this matter it is the only (know) material the would fit the profile perfectly. Far more perfect than I ever expeceted.   First, the presense of large quantities of dark matter around a black hole would explain the mushroom shaped distortion of some of the radiation eminating from a quazar. I would have been happy if it ended there, but like all good stories, this was just the begaining. It ocurred to me that these thin jets of radiation were not the only thing that dark matter pushed around. Suddenly the universe started falling into place like a puzzle that had been put together the whole time, but we were simply to close to see the entire picture.    As different black holes pump out dark matter, the surrounding area fills up, pushing regular matter into clumps, thus explaining the mystery of how galaxies grow. These same forces also explain haw galaxies form on an accretion disk, as the galaxy material "cuts" through the surounding dark matter it causes the dark matter in that area to thin, after that it's natural prosesses that causes the galaxy material to travel the path of least resistanse, increasing it's size and flatening it into a disk.   There is one more affect of the black hole created dark matter theory that I'll address... The expansion of the universe. As most of you are aware the universe is expanding in every direction. Modern theory states that this is causes by a major explosion or a Big Bang. Big Bang theory says that the entire universe was at one point in time condensed to a single point that exploded, sending the first elements shooting in ever direction. Unfortunatly sientists are well aware of the contradictions in this theory. The most obvious problem is that if the universe started with a big bang then everything should be moving away from everything else at the same speed. But we find that isn't the case. In fact, the farther away an object is the faster it's moving away from us. This new dark matter theory has an explanation for that too. It states that as two black holes fill their surrounding area with dark matter, they push away from each other as the space between them becomes filled. This means that the more black holes in an area, the faster the space between them is filled, thus the faster they move apart. The end product is a predictable increase in the rate at which an object moves away from us the farther away it is from us. In other words the more black holes between us and an object, the faster it travels.   In conclusion I urge you to reconcider your views of black holes as an embodiment of destuction, and consider the posibility that they may be the true architechs of our universe.   Thank you for taking the time to read this post. I hope you enjoyed the read. I would love to get some feedback. .

Manafest_Destiny · Jan 14, 2009

In this installment I will address the relationship between dark matter and black holes as theorized by myself. I have had a suprizing amount of feed back regarding this subject, so I have decided to touch base on some of the basic concepts of the theory...  Enjoy!   Ever since Einstein made the world aware of the existance of black holes they have perplexed and fasinated sientists with almost inconcivable ideas of huge masses and distorting space-time. We have almost unanimosly coined them as the devourers of the universe.   Allow us, for a moment, to consider a more Newtonian idea, where light and matter that pass beyond the event horizon are not destroyed, but converted. As matter enters the black hole it is streched, essintialy disintergrting it. Proton and nuetrons are stripped of their electrons as the matter breaks down into an even smaller thread form. Now here comes the fun part. Not only is this trapped light and matter losing substance as it's torn apart at a sub-atomic level, but the distortion of space-time caused by the black hole in addition to the amazing speeds at which the matter..light is moving causes all of this to happen in a nearly timeless enviroment.   This is where our current understanding of mathamatics becomes useless. Because we have no way to see beyond an event horizon, the nessisary variables escape us. Still, it doesn't take much of a stretch to assume that all of that matter..light is not destroyed, simply converted into a form that mirrors the perfect stability of the black hole the spawned it. Naturaly, if black holes create a new material, then the amount of matter consumed by a black hole mutiplied by the enourmous amount of black holes in the universe, would inevitably cause whatever element they created to be the most plentiful matierial in the universe.   Upon searching for an overly ubundant element that was perfectly stable and let off no energy, thus rendering it undetectable by current means, one answer jumped out. Dark matter. Because of the very nature of this matter it is the only (know) material the would fit the profile perfectly. Far more perfect than I ever expeceted.   First, the presense of large quantities of dark matter around a black hole would explain the mushroom shaped distortion of some of the radiation eminating from a quazar. I would have been happy if it ended there, but like all good stories, this was just the begaining. It ocurred to me that these thin jets of radiation were not the only thing that dark matter pushed around. Suddenly the universe started falling into place like a puzzle that had been put together the whole time, but we were simply to close to see the entire picture.    As different black holes pump out dark matter, the surrounding area fills up, pushing regular matter into clumps, thus explaining the mystery of how galaxies grow. These same forces also explain haw galaxies form on an accretion disk, as the galaxy material "cuts" through the surounding dark matter it causes the dark matter in that area to thin, after that it's natural prosesses that causes the galaxy material to travel the path of least resistanse, increasing it's size and flatening it into a disk.   There is one more affect of the black hole created dark matter theory that I'll address... The expansion of the universe. As most of you are aware the universe is expanding in every direction. Modern theory states that this is causes by a major explosion or a Big Bang. Big Bang theory says that the entire universe was at one point in time condensed to a single point that exploded, sending the first elements shooting in ever direction. Unfortunatly sientists are well aware of the contradictions in this theory. The most obvious problem is that if the universe started with a big bang then everything should be moving away from everything else at the same speed. But we find that isn't the case. In fact, the farther away an object is the faster it's moving away from us. This new dark matter theory has an explanation for that too. It states that as two black holes fill their surrounding area with dark matter, they push away from each other as the space between them becomes filled. This means that the more black holes in an area, the faster the space between them is filled, thus the faster they move apart. The end product is a predictable increase in the rate at which an object moves away from us the farther away it is from us. In other words the more black holes between us and an object, the faster it travels.   In conclusion I urge you to reconcider your views of black holes as an embodiment of destuction, and consider the posibility that they may be the true architechs of our universe.   Thank you for taking the time to read this post. I hope you enjoyed the read. I would love to get some feedback. .

SpeedFreek · Jan 15, 2009

Hi there, welcome to Space.com! You seem to have an enthusiastic thirst for knowledge so you have come to the right place.   Replying to: <DIV CLASS='Discussion_PostQuote'>Ever since Einstein made the world aware of the existance of black holes they have perplexed and fasinated sientists with almost inconcivable ideas of huge masses and distorting space-time. We have almost unanimosly coined them as the devourers of the universe.</DIV>But they are subject to the inverse-square law of gravity just like everything else in the universe. They do not hoover up everything around them, only stuff that crosses the event horizon cannot escape. You can move past a black hole without getting sucked in.Replying to: <DIV CLASS='Discussion_PostQuote'>Allow us, for a moment, to consider a more Newtonian idea, where light and matter that pass beyond the event horizon are not destroyed, but converted. As matter enters the black hole it is streched, essintialy disintergrting it. Proton and nuetrons are stripped of their electrons as the matter breaks down into an even smaller thread form. Now here comes the fun part. Not only is this trapped light and matter losing substance as it's torn apart at a sub-atomic level, but the distortion of space-time caused by the black hole in addition to the amazing speeds at which the matter..light is moving causes all of this to happen in a nearly timeless enviroment.</DIV>Tidal forces would cause such a difference between the gravity at your feet and the gravity at your head that you would be "spaghettified"! Your timeless environment is only relative, a second will still last a second for you and your watch would still be ticking when you reach the event horizon (if you weren't spaghettified first!), but to an observer outside the event horizon you would not even be seen to reach the event horizon, due to gravitational time-dilation. At the event horizon you would theoretically look frozen in time to the outside world, but the outside world would need an infinite amount of time to see you get there. Time-dilation is a relative effect, so your timeless environment would only exist for observers outside the event horizon. But none of this is central to your idea anyway, so let's move on...  Replying to: <DIV CLASS='Discussion_PostQuote'>This is where our current understanding of mathamatics becomes useless. Because we have no way to see beyond an event horizon, the nessisary variables escape us. Still, it doesn't take much of a stretch to assume that all of that matter..light is not destroyed, simply converted into a form that mirrors the perfect stability of the black hole the spawned it. Naturaly, if black holes create a new material, then the amount of matter consumed by a black hole mutiplied by the enourmous amount of black holes in the universe, would inevitably cause whatever element they created to be the most plentiful matierial in the universe.</DIV>But gravity seems to act upon whatever dark matter is, the same as other matter, and matter cannot escape the event horizon. And it is dark energy (whatever that is) that is thought to be the most plentiful material in the universe, not dark matter, at a ratio of about 3 to 1. Dark energy is what is thought to be driving the acceleration of the expansion of the universe and dark matter is what is thought to cluster around galaxies, holding them together (in simple terms).  Replying to: <DIV CLASS='Discussion_PostQuote'>There is one more affect of the black hole created dark matter theory that I'll address... The expansion of the universe.</DIV>Ahh good, my favorite subject! Replying to: <DIV CLASS='Discussion_PostQuote'>As most of you are aware the universe is expanding in every direction. Modern theory states that this is causes by a major explosion or a Big Bang. Big Bang theory says that the entire universe was at one point in time condensed to a single point that exploded, sending the first elements shooting in ever direction. Unfortunatly sientists are well aware of the contradictions in this theory. The most obvious problem is that if the universe started with a big bang then everything should be moving away from everything else at the same speed. But we find that isn't the case. In fact, the farther away an object is the faster it's moving away from us.</DIV>It is a common misconception that the universe was supposed to be like an explosion. It is more accurately explained as an expanding volume of space with stuff in it, where the distance in between any given coordinates within that volume increases by the same factor at any given time. So in the time that 1 meter becomes 2 meters, 100 meters becomes 200 meters. If the volume is expanding evenly throughout at any given time, even if the rate of expansion changes, objects that were originally equidistant remain equidistant, but the measure of distance changes. Let's make a model here, to illustrate exactly what I mean.Now to model an expanding volume with space in it, we need to assign coordinates within that space. For the moment, forget about any edges to the volume, we don't need edges, we just need coordinates in order to measure the expansion of a volume of space. Galaxies come later, so for now just imagine a 3 dimensional grid. At each grid intersection we will assign a coordinate, a point, a dot. Let's say each intersection point is 1 meter apart. Put yourself on a point somewhere in this volume. Whatever axis you look along you see neighbouring points 1, 2, 3, 4, 5 etc meters away, receding off into the distance. Then we introduce some expansion. Let's say the volume grows to 10 times its original size in 1 second! That seems fast perhaps, but this is just a model with easy numbers. The key thing to remember is that the grid expands with the volume. So, here we are, still sitting on our point (but it could have been any point) 1 second later. Now lets look along an axis. We see those neighbouring points are now 10, 20, 30, 40, 50 etc meters away. The volume increased to 10 times the size, and so did the distance between each intersection point on that grid. Our nearest neighbouring point has receded from 1 to 10 meters in 1 second, so it has receded at 9 meters per second. The next point away has receded from 2 to 20 meters in 1 second, so that point receded at 18 meters per second. The fifth point has moved from 5 to 50 meters away in 1 second, so that one has receded at 45 meters per second. The further away you look, the faster a point will seem to have receded! And the view would be the same, whatever viewpoint you choose in the grid. Remember I said the grid of points receded off into the distance.. well a point that was initially 33,000,000 meters away will have moved away to 330,000,000 meters in 1 one second, meaning that it has receded at 300,000,000 meters per second - the speed of light. Any point initially more distant than 33,000,000 meters away from another point will have receded from that point faster than the speed of light. That is the distance were an object recedes at light speed in this "little" model of expansion. If you look at a point that has receded at the speed of light, then from that point, the point you are on has receded at the speed of light. Now I know this is a very simple model, dealing with a simple 10 times expansion in 1 second. This might seem very different from a universe where the rate of expansion was slowing from immense speed and then starting to accelerate, but if you start your grid very small and apply different rates of expansion to that grid, incrementally, over different rates of time, to simulate slowing it down and then speeding it up, when you look at the end result it is essentially the same. (Whenever there is a change in the rate of expansion, it is the rate of expansion for the whole grid that changes). You might be asking how useful this model actually is. Well you can substitute light years for meters and use time-scales over billions of years if you like but the principle remains. If you sprinkle clusters of galaxies through the grid at random and then expand that grid and have clusters move with it, you get effects pretty much like how we think the universe expands. So hopefully you can now see why the observation that the further away a galaxy is, the faster it seems to recede, is true whether the rate of expansion is decelerating, constant, or accelerating. The fact that the most distant galaxies are receding the fastest is not the reason we think the rate of expansion is accelerating.Before you go any further with your thought-experiments, it might be worth you having a look at what the real scientific view of the universe is, so here is a good introduction.Misconceptions about the Big Bang.Also, I should point out that when our observable universe was a "singularity", (which doesn't necessarily mean it was point-like, let's just say it was very small), the whole universe might have already been absolutely huge, or possibly even infinite. We might be able to theoretically trace our observable universe (including the parts that were not observable after inflation but would have been observable without/before inflation) back to a very small volume, but that isn't neccesarily all the universe there was at the time. This really is mind-bending stuff!  But what is most important is that you enjoy learning about the universe, so keep it up! <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-smile.gif" border="0" alt="Smile" title="Smile" /> <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

SpeedFreek · Jan 15, 2009

Hi there, welcome to Space.com! You seem to have an enthusiastic thirst for knowledge so you have come to the right place.   Replying to: <DIV CLASS='Discussion_PostQuote'>Ever since Einstein made the world aware of the existance of black holes they have perplexed and fasinated sientists with almost inconcivable ideas of huge masses and distorting space-time. We have almost unanimosly coined them as the devourers of the universe.</DIV>But they are subject to the inverse-square law of gravity just like everything else in the universe. They do not hoover up everything around them, only stuff that crosses the event horizon cannot escape. You can move past a black hole without getting sucked in.Replying to: <DIV CLASS='Discussion_PostQuote'>Allow us, for a moment, to consider a more Newtonian idea, where light and matter that pass beyond the event horizon are not destroyed, but converted. As matter enters the black hole it is streched, essintialy disintergrting it. Proton and nuetrons are stripped of their electrons as the matter breaks down into an even smaller thread form. Now here comes the fun part. Not only is this trapped light and matter losing substance as it's torn apart at a sub-atomic level, but the distortion of space-time caused by the black hole in addition to the amazing speeds at which the matter..light is moving causes all of this to happen in a nearly timeless enviroment.</DIV>Tidal forces would cause such a difference between the gravity at your feet and the gravity at your head that you would be "spaghettified"! Your timeless environment is only relative, a second will still last a second for you and your watch would still be ticking when you reach the event horizon (if you weren't spaghettified first!), but to an observer outside the event horizon you would not even be seen to reach the event horizon, due to gravitational time-dilation. At the event horizon you would theoretically look frozen in time to the outside world, but the outside world would need an infinite amount of time to see you get there. Time-dilation is a relative effect, so your timeless environment would only exist for observers outside the event horizon. But none of this is central to your idea anyway, so let's move on...  Replying to: <DIV CLASS='Discussion_PostQuote'>This is where our current understanding of mathamatics becomes useless. Because we have no way to see beyond an event horizon, the nessisary variables escape us. Still, it doesn't take much of a stretch to assume that all of that matter..light is not destroyed, simply converted into a form that mirrors the perfect stability of the black hole the spawned it. Naturaly, if black holes create a new material, then the amount of matter consumed by a black hole mutiplied by the enourmous amount of black holes in the universe, would inevitably cause whatever element they created to be the most plentiful matierial in the universe.</DIV>But gravity seems to act upon whatever dark matter is, the same as other matter, and matter cannot escape the event horizon. And it is dark energy (whatever that is) that is thought to be the most plentiful material in the universe, not dark matter, at a ratio of about 3 to 1. Dark energy is what is thought to be driving the acceleration of the expansion of the universe and dark matter is what is thought to cluster around galaxies, holding them together (in simple terms).  Replying to: <DIV CLASS='Discussion_PostQuote'>There is one more affect of the black hole created dark matter theory that I'll address... The expansion of the universe.</DIV>Ahh good, my favorite subject! Replying to: <DIV CLASS='Discussion_PostQuote'>As most of you are aware the universe is expanding in every direction. Modern theory states that this is causes by a major explosion or a Big Bang. Big Bang theory says that the entire universe was at one point in time condensed to a single point that exploded, sending the first elements shooting in ever direction. Unfortunatly sientists are well aware of the contradictions in this theory. The most obvious problem is that if the universe started with a big bang then everything should be moving away from everything else at the same speed. But we find that isn't the case. In fact, the farther away an object is the faster it's moving away from us.</DIV>It is a common misconception that the universe was supposed to be like an explosion. It is more accurately explained as an expanding volume of space with stuff in it, where the distance in between any given coordinates within that volume increases by the same factor at any given time. So in the time that 1 meter becomes 2 meters, 100 meters becomes 200 meters. If the volume is expanding evenly throughout at any given time, even if the rate of expansion changes, objects that were originally equidistant remain equidistant, but the measure of distance changes. Let's make a model here, to illustrate exactly what I mean.Now to model an expanding volume with space in it, we need to assign coordinates within that space. For the moment, forget about any edges to the volume, we don't need edges, we just need coordinates in order to measure the expansion of a volume of space. Galaxies come later, so for now just imagine a 3 dimensional grid. At each grid intersection we will assign a coordinate, a point, a dot. Let's say each intersection point is 1 meter apart. Put yourself on a point somewhere in this volume. Whatever axis you look along you see neighbouring points 1, 2, 3, 4, 5 etc meters away, receding off into the distance. Then we introduce some expansion. Let's say the volume grows to 10 times its original size in 1 second! That seems fast perhaps, but this is just a model with easy numbers. The key thing to remember is that the grid expands with the volume. So, here we are, still sitting on our point (but it could have been any point) 1 second later. Now lets look along an axis. We see those neighbouring points are now 10, 20, 30, 40, 50 etc meters away. The volume increased to 10 times the size, and so did the distance between each intersection point on that grid. Our nearest neighbouring point has receded from 1 to 10 meters in 1 second, so it has receded at 9 meters per second. The next point away has receded from 2 to 20 meters in 1 second, so that point receded at 18 meters per second. The fifth point has moved from 5 to 50 meters away in 1 second, so that one has receded at 45 meters per second. The further away you look, the faster a point will seem to have receded! And the view would be the same, whatever viewpoint you choose in the grid. Remember I said the grid of points receded off into the distance.. well a point that was initially 33,000,000 meters away will have moved away to 330,000,000 meters in 1 one second, meaning that it has receded at 300,000,000 meters per second - the speed of light. Any point initially more distant than 33,000,000 meters away from another point will have receded from that point faster than the speed of light. That is the distance were an object recedes at light speed in this "little" model of expansion. If you look at a point that has receded at the speed of light, then from that point, the point you are on has receded at the speed of light. Now I know this is a very simple model, dealing with a simple 10 times expansion in 1 second. This might seem very different from a universe where the rate of expansion was slowing from immense speed and then starting to accelerate, but if you start your grid very small and apply different rates of expansion to that grid, incrementally, over different rates of time, to simulate slowing it down and then speeding it up, when you look at the end result it is essentially the same. (Whenever there is a change in the rate of expansion, it is the rate of expansion for the whole grid that changes). You might be asking how useful this model actually is. Well you can substitute light years for meters and use time-scales over billions of years if you like but the principle remains. If you sprinkle clusters of galaxies through the grid at random and then expand that grid and have clusters move with it, you get effects pretty much like how we think the universe expands. So hopefully you can now see why the observation that the further away a galaxy is, the faster it seems to recede, is true whether the rate of expansion is decelerating, constant, or accelerating. The fact that the most distant galaxies are receding the fastest is not the reason we think the rate of expansion is accelerating.Before you go any further with your thought-experiments, it might be worth you having a look at what the real scientific view of the universe is, so here is a good introduction.Misconceptions about the Big Bang.Also, I should point out that when our observable universe was a "singularity", (which doesn't necessarily mean it was point-like, let's just say it was very small), the whole universe might have already been absolutely huge, or possibly even infinite. We might be able to theoretically trace our observable universe (including the parts that were not observable after inflation but would have been observable without/before inflation) back to a very small volume, but that isn't neccesarily all the universe there was at the time. This really is mind-bending stuff!  But what is most important is that you enjoy learning about the universe, so keep it up! <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-smile.gif" border="0" alt="Smile" title="Smile" /> <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

origin · Jan 20, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Hi there, welcome to Space.com! You seem to have an enthusiastic thirst for knowledge so you have come to the right place.  But they are subject to the inverse-square law of gravity just like everything else in the universe. They do not hoover up everything around them, only stuff that crosses the event horizon cannot escape. You can move past a black hole without getting sucked in.Tidal forces would cause such a difference between the gravity at your feet and the gravity at your head that you would be "spaghettified"! Your timeless environment is only relative, a second will still last a second for you and your watch would still be ticking when you reach the event horizon (if you weren't spaghettified first!), but to an observer outside the event horizon you would not even be seen to reach the event horizon, due to gravitational time-dilation. At the event horizon you would theoretically look frozen in time to the outside world, but the outside world would need an infinite amount of time to see you get there. Time-dilation is a relative effect, so your timeless environment would only exist for observers outside the event horizon. But none of this is central to your idea anyway, so let's move on...  But gravity seems to act upon whatever dark matter is, the same as other matter, and matter cannot escape the event horizon. And it is dark energy (whatever that is) that is thought to be the most plentiful material in the universe, not dark matter, at a ratio of about 3 to 1. Dark energy is what is thought to be driving the acceleration of the expansion of the universe and dark matter is what is thought to cluster around galaxies, holding them together (in simple terms).  Ahh good, my favorite subject! It is a common misconception that the universe was supposed to be like an explosion. It is more accurately explained as an expanding volume of space with stuff in it, where the distance in between any given coordinates within that volume increases by the same factor at any given time. So in the time that 1 meter becomes 2 meters, 100 meters becomes 200 meters. If the volume is expanding evenly throughout at any given time, even if the rate of expansion changes, objects that were originally equidistant remain equidistant, but the measure of distance changes. Let's make a model here, to illustrate exactly what I mean.Now to model an expanding volume with space in it, we need to assign coordinates within that space. For the moment, forget about any edges to the volume, we don't need edges, we just need coordinates in order to measure the expansion of a volume of space. Galaxies come later, so for now just imagine a 3 dimensional grid. At each grid intersection we will assign a coordinate, a point, a dot. Let's say each intersection point is 1 meter apart.Put yourself on a point somewhere in this volume. Whatever axis you look along you see neighbouring points 1, 2, 3, 4, 5 etc meters away, receding off into the distance. Then we introduce some expansion. Let's say the volume grows to 10 times its original size in 1 second! That seems fast perhaps, but this is just a model with easy numbers. The key thing to remember is that the grid expands with the volume.So, here we are, still sitting on our point (but it could have been any point) 1 second later. Now lets look along an axis. We see those neighbouring points are now 10, 20, 30, 40, 50 etc meters away. The volume increased to 10 times the size, and so did the distance between each intersection point on that grid.Our nearest neighbouring point has receded from 1 to 10 meters in 1 second, so it has receded at 9 meters per second. The next point away has receded from 2 to 20 meters in 1 second, so that point receded at 18 meters per second. The fifth point has moved from 5 to 50 meters away in 1 second, so that one has receded at 45 meters per second. The further away you look, the faster a point will seem to have receded! And the view would be the same, whatever viewpoint you choose in the grid.Remember I said the grid of points receded off into the distance.. well a point that was initially 33,000,000 meters away will have moved away to 330,000,000 meters in 1 one second, meaning that it has receded at 300,000,000 meters per second - the speed of light. Any point initially more distant than 33,000,000 meters away from another point will have receded from that point faster than the speed of light. That is the distance were an object recedes at light speed in this "little" model of expansion. If you look at a point that has receded at the speed of light, then from that point, the point you are on has receded at the speed of light. Now I know this is a very simple model, dealing with a simple 10 times expansion in 1 second. This might seem very different from a universe where the rate of expansion was slowing from immense speed and then starting to accelerate, but if you start your grid very small and apply different rates of expansion to that grid, incrementally, over different rates of time, to simulate slowing it down and then speeding it up, when you look at the end result it is essentially the same. (Whenever there is a change in the rate of expansion, it is the rate of expansion for the whole grid that changes). You might be asking how useful this model actually is. Well you can substitute light years for meters and use time-scales over billions of years if you like but the principle remains. If you sprinkle clusters of galaxies through the grid at random and then expand that grid and have clusters move with it, you get effects pretty much like how we think the universe expands.So hopefully you can now see why the observation that the further away a galaxy is, the faster it seems to recede, is true whether the rate of expansion is decelerating, constant, or accelerating. The fact that the most distant galaxies are receding the fastest is not the reason we think the rate of expansion is accelerating.Before you go any further with your thought-experiments, it might be worth you having a look at what the real scientific view of the universe is, so here is a good introduction.Misconceptions about the Big Bang.Also, I should point out that when our observable universe was a "singularity", (which doesn't necessarily mean it was point-like, let's just say it was very small), the whole universe might have already been absolutely huge, or possibly even infinite. We might be able to theoretically trace our observable universe (including the parts that were not observable after inflation but would have been observable without/before inflation) back to a very small volume, but that isn't neccesarily all the universe there was at the time. This really is mind-bending stuff!  But what is most important is that you enjoy learning about the universe, so keep it up! Posted by SpeedFreek</DIV> As always well written, easy to understand, and accurate.  Good job. <div class="Discussion_UserSignature"> </div>

origin · Jan 20, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Hi there, welcome to Space.com! You seem to have an enthusiastic thirst for knowledge so you have come to the right place.  But they are subject to the inverse-square law of gravity just like everything else in the universe. They do not hoover up everything around them, only stuff that crosses the event horizon cannot escape. You can move past a black hole without getting sucked in.Tidal forces would cause such a difference between the gravity at your feet and the gravity at your head that you would be "spaghettified"! Your timeless environment is only relative, a second will still last a second for you and your watch would still be ticking when you reach the event horizon (if you weren't spaghettified first!), but to an observer outside the event horizon you would not even be seen to reach the event horizon, due to gravitational time-dilation. At the event horizon you would theoretically look frozen in time to the outside world, but the outside world would need an infinite amount of time to see you get there. Time-dilation is a relative effect, so your timeless environment would only exist for observers outside the event horizon. But none of this is central to your idea anyway, so let's move on...  But gravity seems to act upon whatever dark matter is, the same as other matter, and matter cannot escape the event horizon. And it is dark energy (whatever that is) that is thought to be the most plentiful material in the universe, not dark matter, at a ratio of about 3 to 1. Dark energy is what is thought to be driving the acceleration of the expansion of the universe and dark matter is what is thought to cluster around galaxies, holding them together (in simple terms).  Ahh good, my favorite subject! It is a common misconception that the universe was supposed to be like an explosion. It is more accurately explained as an expanding volume of space with stuff in it, where the distance in between any given coordinates within that volume increases by the same factor at any given time. So in the time that 1 meter becomes 2 meters, 100 meters becomes 200 meters. If the volume is expanding evenly throughout at any given time, even if the rate of expansion changes, objects that were originally equidistant remain equidistant, but the measure of distance changes. Let's make a model here, to illustrate exactly what I mean.Now to model an expanding volume with space in it, we need to assign coordinates within that space. For the moment, forget about any edges to the volume, we don't need edges, we just need coordinates in order to measure the expansion of a volume of space. Galaxies come later, so for now just imagine a 3 dimensional grid. At each grid intersection we will assign a coordinate, a point, a dot. Let's say each intersection point is 1 meter apart.Put yourself on a point somewhere in this volume. Whatever axis you look along you see neighbouring points 1, 2, 3, 4, 5 etc meters away, receding off into the distance. Then we introduce some expansion. Let's say the volume grows to 10 times its original size in 1 second! That seems fast perhaps, but this is just a model with easy numbers. The key thing to remember is that the grid expands with the volume.So, here we are, still sitting on our point (but it could have been any point) 1 second later. Now lets look along an axis. We see those neighbouring points are now 10, 20, 30, 40, 50 etc meters away. The volume increased to 10 times the size, and so did the distance between each intersection point on that grid.Our nearest neighbouring point has receded from 1 to 10 meters in 1 second, so it has receded at 9 meters per second. The next point away has receded from 2 to 20 meters in 1 second, so that point receded at 18 meters per second. The fifth point has moved from 5 to 50 meters away in 1 second, so that one has receded at 45 meters per second. The further away you look, the faster a point will seem to have receded! And the view would be the same, whatever viewpoint you choose in the grid.Remember I said the grid of points receded off into the distance.. well a point that was initially 33,000,000 meters away will have moved away to 330,000,000 meters in 1 one second, meaning that it has receded at 300,000,000 meters per second - the speed of light. Any point initially more distant than 33,000,000 meters away from another point will have receded from that point faster than the speed of light. That is the distance were an object recedes at light speed in this "little" model of expansion. If you look at a point that has receded at the speed of light, then from that point, the point you are on has receded at the speed of light. Now I know this is a very simple model, dealing with a simple 10 times expansion in 1 second. This might seem very different from a universe where the rate of expansion was slowing from immense speed and then starting to accelerate, but if you start your grid very small and apply different rates of expansion to that grid, incrementally, over different rates of time, to simulate slowing it down and then speeding it up, when you look at the end result it is essentially the same. (Whenever there is a change in the rate of expansion, it is the rate of expansion for the whole grid that changes). You might be asking how useful this model actually is. Well you can substitute light years for meters and use time-scales over billions of years if you like but the principle remains. If you sprinkle clusters of galaxies through the grid at random and then expand that grid and have clusters move with it, you get effects pretty much like how we think the universe expands.So hopefully you can now see why the observation that the further away a galaxy is, the faster it seems to recede, is true whether the rate of expansion is decelerating, constant, or accelerating. The fact that the most distant galaxies are receding the fastest is not the reason we think the rate of expansion is accelerating.Before you go any further with your thought-experiments, it might be worth you having a look at what the real scientific view of the universe is, so here is a good introduction.Misconceptions about the Big Bang.Also, I should point out that when our observable universe was a "singularity", (which doesn't necessarily mean it was point-like, let's just say it was very small), the whole universe might have already been absolutely huge, or possibly even infinite. We might be able to theoretically trace our observable universe (including the parts that were not observable after inflation but would have been observable without/before inflation) back to a very small volume, but that isn't neccesarily all the universe there was at the time. This really is mind-bending stuff!  But what is most important is that you enjoy learning about the universe, so keep it up! Posted by SpeedFreek</DIV> As always well written, easy to understand, and accurate.  Good job. <div class="Discussion_UserSignature"> </div>

10_stone_5 · Jan 21, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Misconceptions about the Big Bang.Also, I should point out that when our observable universe was a "singularity", (which doesn't necessarily mean it was point-like, let's just say it was very small) ... Posted by SpeedFreek</DIV>I like Poul Andersen's description of the 'singularity' as a monobloc. <div class="Discussion_UserSignature"> </div>

10_stone_5 · Jan 21, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Misconceptions about the Big Bang.Also, I should point out that when our observable universe was a "singularity", (which doesn't necessarily mean it was point-like, let's just say it was very small) ... Posted by SpeedFreek</DIV>I like Poul Andersen's description of the 'singularity' as a monobloc. <div class="Discussion_UserSignature"> </div>

neilsox · Jan 21, 2009

As far as I know, the speedfreek description agrees with the mainstream except, he likely should have said 1000 times volume increase to go with the ten times spacing increase. Area would increase by 100 times.   Neil

neilsox · Jan 21, 2009

As far as I know, the speedfreek description agrees with the mainstream except, he likely should have said 1000 times volume increase to go with the ten times spacing increase. Area would increase by 100 times.   Neil

BoJangles · Jan 21, 2009

<edited for readability> Im just curious here, is there any evidence of dark matter existing with out an assicotiated black hole ( galactic ) in the vicinity.I.e i know about the bullet galaxy but presumably they (both) had galactic black holes. i think since dark matter is an open topic nothing can be excluded, unless otherwise proven.So question, are there galaxies with-out galactic black holes, and do these galaxies exhibit a lack of dark matter?Also i was reading somewhere the other day, some close satellite galaxies don't exhibit galactic black holes, though do these galaxies show a lack of dark matter?  <div class="Discussion_UserSignature"> -------------- Let me start out with the standard disclaimer ... I am an idiot, I know almost nothing, I haven’t taken calculus, I don’t work for NASA, and I am one-quarter Bulgarian sheep dog. With that out of the way, I have several stupid questions... *** A few months blogging can save a few hours in research *** </div>

BoJangles · Jan 21, 2009

<edited for readability> Im just curious here, is there any evidence of dark matter existing with out an assicotiated black hole ( galactic ) in the vicinity.I.e i know about the bullet galaxy but presumably they (both) had galactic black holes. i think since dark matter is an open topic nothing can be excluded, unless otherwise proven.So question, are there galaxies with-out galactic black holes, and do these galaxies exhibit a lack of dark matter?Also i was reading somewhere the other day, some close satellite galaxies don't exhibit galactic black holes, though do these galaxies show a lack of dark matter?  <div class="Discussion_UserSignature"> -------------- Let me start out with the standard disclaimer ... I am an idiot, I know almost nothing, I haven’t taken calculus, I don’t work for NASA, and I am one-quarter Bulgarian sheep dog. With that out of the way, I have several stupid questions... *** A few months blogging can save a few hours in research *** </div>

origin · Jan 21, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>As far as I know, the speedfreek description agrees with the mainstream except, he likely should have said 1000 times volume increase to go with the ten times spacing increase. Area would increase by 100 times.   Neil Posted by neilsox</DIV> Good catch neilsox.  He should just talk about the diameter increase of the universe instead of the volume increase so as not to confuse the less math savy people, or me as it turns out!  <div class="Discussion_UserSignature"> </div>

origin · Jan 21, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>As far as I know, the speedfreek description agrees with the mainstream except, he likely should have said 1000 times volume increase to go with the ten times spacing increase. Area would increase by 100 times.   Neil Posted by neilsox</DIV> Good catch neilsox.  He should just talk about the diameter increase of the universe instead of the volume increase so as not to confuse the less math savy people, or me as it turns out!  <div class="Discussion_UserSignature"> </div>

SpeedFreek · Jan 21, 2009

Trust me, there is no difference, as I was talking about the scale factor.  The scale factor of the universe has increased by around 1100 times since the CMBR was emitted. My "10 times expansion in 1 second" was, as I said, just an arbitrary choice to keep the numbers easy for that example.If the scale factor has increased by 1100 times since the CMBR was emitted, then so has the distance measure. Thus, the current mainstream view is that the CMBR photons that we currently detect were originally emitted at a distance of only 42 million light-years away, and that coordinate that they were emitted from has receded to 46 billion light-years away in the 13.7 billion years since. 42 million * 1100 = 46 billion.It is the scale factor that counts, and that is what I was trying to explain in my original answer. If the scale factor were 10, then all distances would have increased by a factor of 10 and the radius (and the diameter!) of the universe would have increased by a factor of 10. I wasn't measuring the increase in cubic volume, I was talking about the factor by which the volume had expanded. Getting into things like the increase in volume and area just complicates things, so I only talk in terms of distance and the expansion factor.Neilsox's observation, whilst valid, is not what I was refering to when I said "the volume increased to 10 times the size", but perhaps I should reword it next time to say the diameter of the volume is 10 times larger. The problem I have with that is it implies a sphere and I want to avoid putting a boundary on the volume, as we don't know if the universe has a boundary or not. When you see mention of cosmological redshift, it is usually written as the scale factor, in the form 1+z. So if you are looking at a galaxy with a redshift of z=7, the universe is now 8 times larger and that galaxy is now 8 times further away than it was when the light from that galaxy was emitted. When you look at a galaxy at z=1, you are looking at light that was emitted when the universe was half the size it is today. If a CMBR photon has a redshift of z=1089, the universe is now 1090 times larger than it was when that photon was emitted, and so on. <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

SpeedFreek · Jan 21, 2009

Trust me, there is no difference, as I was talking about the scale factor.  The scale factor of the universe has increased by around 1100 times since the CMBR was emitted. My "10 times expansion in 1 second" was, as I said, just an arbitrary choice to keep the numbers easy for that example.If the scale factor has increased by 1100 times since the CMBR was emitted, then so has the distance measure. Thus, the current mainstream view is that the CMBR photons that we currently detect were originally emitted at a distance of only 42 million light-years away, and that coordinate that they were emitted from has receded to 46 billion light-years away in the 13.7 billion years since. 42 million * 1100 = 46 billion.It is the scale factor that counts, and that is what I was trying to explain in my original answer. If the scale factor were 10, then all distances would have increased by a factor of 10 and the radius (and the diameter!) of the universe would have increased by a factor of 10. I wasn't measuring the increase in cubic volume, I was talking about the factor by which the volume had expanded. Getting into things like the increase in volume and area just complicates things, so I only talk in terms of distance and the expansion factor.Neilsox's observation, whilst valid, is not what I was refering to when I said "the volume increased to 10 times the size", but perhaps I should reword it next time to say the diameter of the volume is 10 times larger. The problem I have with that is it implies a sphere and I want to avoid putting a boundary on the volume, as we don't know if the universe has a boundary or not. When you see mention of cosmological redshift, it is usually written as the scale factor, in the form 1+z. So if you are looking at a galaxy with a redshift of z=7, the universe is now 8 times larger and that galaxy is now 8 times further away than it was when the light from that galaxy was emitted. When you look at a galaxy at z=1, you are looking at light that was emitted when the universe was half the size it is today. If a CMBR photon has a redshift of z=1089, the universe is now 1090 times larger than it was when that photon was emitted, and so on. <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

origin · Jan 21, 2009

Put yourself on a point somewhere in this volume. Whatever axis you look along you see neighbouring points 1, 2, 3, 4, 5 etc meters away, receding off into the distance. Then we introduce some expansion. Let's say the volume grows to 10 times its original size in 1 second! That seems fast perhaps, but this is just a model with easy numbers. The key thing to remember is that the grid expands with the volume.So, here we are, still sitting on our point (but it could have been any point) 1 second later. Now lets look along an axis. We see those neighbouring points are now 10, 20, 30, 40, 50 etc meters away. The volume increased to 10 times the size, and so did the distance between each intersection point on that grid.Speedfreak, his point is correct, if the volume increased by 10. then the distances between points will not also increase by a factor of 10.  Your idea is dead on it is just that you are just forgeting that volume cubed and the distance is not.volume increases from 10m to 100m.10m = 4/3pi*r^3    ::  r = 1.34m100m = 4/3pir^3    :: r = 2.88mThe linear distance does not increase by a factor of 10 <div class="Discussion_UserSignature"> </div>

origin · Jan 21, 2009

Put yourself on a point somewhere in this volume. Whatever axis you look along you see neighbouring points 1, 2, 3, 4, 5 etc meters away, receding off into the distance. Then we introduce some expansion. Let's say the volume grows to 10 times its original size in 1 second! That seems fast perhaps, but this is just a model with easy numbers. The key thing to remember is that the grid expands with the volume.So, here we are, still sitting on our point (but it could have been any point) 1 second later. Now lets look along an axis. We see those neighbouring points are now 10, 20, 30, 40, 50 etc meters away. The volume increased to 10 times the size, and so did the distance between each intersection point on that grid.Speedfreak, his point is correct, if the volume increased by 10. then the distances between points will not also increase by a factor of 10.  Your idea is dead on it is just that you are just forgeting that volume cubed and the distance is not.volume increases from 10m to 100m.10m = 4/3pi*r^3    ::  r = 1.34m100m = 4/3pir^3    :: r = 2.88mThe linear distance does not increase by a factor of 10 <div class="Discussion_UserSignature"> </div>

derekmcd · Jan 22, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'><edited for readability> Im just curious here, is there any evidence of dark matter existing with out an assicotiated black hole ( galactic ) in the vicinity.I.e i know about the bullet galaxy but presumably they (both) had galactic black holes. i think since dark matter is an open topic nothing can be excluded, unless otherwise proven.So question, are there galaxies with-out galactic black holes, and do these galaxies exhibit a lack of dark matter?Also i was reading somewhere the other day, some close satellite galaxies don't exhibit galactic black holes, though do these galaxies show a lack of dark matter?  Posted by BoJangles</DIV>There were a couple papers last year concerning this.  One was a search for intermediate sized black holes in dwarf galaxies.  I believe the results were negative placing constraints on smaller black holes merging to form supermassive black holes.The other was the discovery of several dwarf/satellite galaxies in the local group that were of extreme low luminosity.  However, by measuring their rotations and orbits within the local group, they were far more massive than their luminosity suggested.  In other words, they are heavily influenced by dark matter.My recollection of these papers may be lacking and don't have time to dig them up, but they're out there.  The point being is that there is no direct corelation between supermassive black holes and whether smaller galaxies have dark matter or not.  It would appear that any massive concentration of matter will involve dark matter to varying degrees. <div class="Discussion_UserSignature"> <div> </div> <div>"If something's hard to do, then it's not worth doing." - Homer Simpson</div> </div>

derekmcd · Jan 22, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'><edited for readability> Im just curious here, is there any evidence of dark matter existing with out an assicotiated black hole ( galactic ) in the vicinity.I.e i know about the bullet galaxy but presumably they (both) had galactic black holes. i think since dark matter is an open topic nothing can be excluded, unless otherwise proven.So question, are there galaxies with-out galactic black holes, and do these galaxies exhibit a lack of dark matter?Also i was reading somewhere the other day, some close satellite galaxies don't exhibit galactic black holes, though do these galaxies show a lack of dark matter?  Posted by BoJangles</DIV>There were a couple papers last year concerning this.  One was a search for intermediate sized black holes in dwarf galaxies.  I believe the results were negative placing constraints on smaller black holes merging to form supermassive black holes.The other was the discovery of several dwarf/satellite galaxies in the local group that were of extreme low luminosity.  However, by measuring their rotations and orbits within the local group, they were far more massive than their luminosity suggested.  In other words, they are heavily influenced by dark matter.My recollection of these papers may be lacking and don't have time to dig them up, but they're out there.  The point being is that there is no direct corelation between supermassive black holes and whether smaller galaxies have dark matter or not.  It would appear that any massive concentration of matter will involve dark matter to varying degrees. <div class="Discussion_UserSignature"> <div> </div> <div>"If something's hard to do, then it's not worth doing." - Homer Simpson</div> </div>

BoJangles · Jan 22, 2009

Thanks derekmcd, that pretty well answered my question. <div class="Discussion_UserSignature"> -------------- Let me start out with the standard disclaimer ... I am an idiot, I know almost nothing, I haven’t taken calculus, I don’t work for NASA, and I am one-quarter Bulgarian sheep dog. With that out of the way, I have several stupid questions... *** A few months blogging can save a few hours in research *** </div>

BoJangles · Jan 22, 2009

Thanks derekmcd, that pretty well answered my question. <div class="Discussion_UserSignature"> -------------- Let me start out with the standard disclaimer ... I am an idiot, I know almost nothing, I haven’t taken calculus, I don’t work for NASA, and I am one-quarter Bulgarian sheep dog. With that out of the way, I have several stupid questions... *** A few months blogging can save a few hours in research *** </div>

yevaud · Jan 22, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>I like Poul Andersen's description of the 'singularity' as a monobloc. Posted by 10_stone_5</DIV>That was actually said by someone - I can't quite recollect whom, but one of the Physics greats - who referred to the original conglomeration of matter from which the Big Bang occurred as the "Primordial Monobloc." <div class="Discussion_UserSignature"> Differential Diagnosis: "I am both amused and annoyed that you think I should be less stubborn than you are." </div>

yevaud · Jan 22, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>I like Poul Andersen's description of the 'singularity' as a monobloc. Posted by 10_stone_5</DIV>That was actually said by someone - I can't quite recollect whom, but one of the Physics greats - who referred to the original conglomeration of matter from which the Big Bang occurred as the "Primordial Monobloc." <div class="Discussion_UserSignature"> Differential Diagnosis: "I am both amused and annoyed that you think I should be less stubborn than you are." </div>

SpeedFreek · Jan 22, 2009

Replying to: <DIV CLASS='Discussion_PostQuote'>Speedfreak, his point is correct, if the volume increased by 10. then the distances between points will not also increase by a factor of 10.  Your idea is dead on it is just that you are just forgeting that volume cubed and the distance is not.volume increases from 10m to 100m.10m = 4/3pi*r^3    ::  r = 1.34m100m = 4/3pir^3    :: r = 2.88mThe linear distance does not increase by a factor of 10 Posted by origin</DIV>Yes, Neils point is correct as I already said, so I obviously need to reword my explanation! (Anyone know a good editor?)The basic point is that if the cosmic scale factor (1+z) doubles, then all distances double and the radius, the diameter, the size of the universe doubles. If the scale factor is 10, then all distances increase 10 times and the diameter of the universe is 10 times bigger. If the universe is now 1100 times larger (in diameter) than when the CMBR was emitted, then the metric that defines distance has increased 1100 times and a coordinate that is co-moving with the expansion is now 1100 times further away than it was when the CMBR was emitted. It is my terminology that is confusing the issue, so I will have to avoid using the word "volume" and just call it the diameter of the universe instead.If my conceptual 3D grid, which expands with the universe, increases in diameter (now that sounds wrong, how can a boundless grid have a diameter? But if I use the word "size" does it imply I am talking about the volume of the grid?) by a factor of 10, then all intersection points become 10 times more distant from their neighbouring points, and the whole grid is now 10 times larger than it was to begin with. Any two points on that grid, however far away from each other they were to begin with, they end up 10 times more distant. I was always talking about the distance measure within a volume of space. Obviously, I introduced a problem when I said the "volume grows to 10 times its original size". I meant the distance across that volume, the diameter of that volume, not the volume of the volume! Who on Earth talks about the volume of the universe?! I was talking about a volume of space increasing in size, not the volume of space increasing in size. But it was my bad wording that caused this mess as the word could be taken in the wrong context. Thanks for the heads-up guys, it took me a while to realise what the problem was. I was just modelling an expanding volume of space by embedding a grid in it and talking in terms of the distance measure for that grid. I will in future try to avoid using the word volume when describing distance across a volume of space. I can see how using the word is misleading. Just as long as you understand that the expanding grid model is a useful tool for showing how the further away an object is, the faster it will recede if the whole, err.. thing increases in size equally throughout. <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-wink.gif" border="0" alt="Wink" title="Wink" /> <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

The relation beween black holes and dark matter.

Manafest_Destiny

Guest

Manafest_Destiny

Guest

SpeedFreek

Guest

SpeedFreek

Guest

origin

Guest

origin

Guest

10_stone_5

Guest

10_stone_5

Guest

neilsox

Guest

neilsox

Guest

BoJangles

Guest

BoJangles

Guest

origin

Guest

origin

Guest

SpeedFreek

Guest

SpeedFreek

Guest

origin

Guest

origin

Guest

derekmcd

Guest

derekmcd

Guest

BoJangles

Guest

BoJangles

Guest

yevaud

Guest

yevaud

Guest

SpeedFreek

Guest

Similar threads

TRENDING THREADS

Latest posts

Share this page