Expanding Universe

KickLaBuka · Aug 18, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>How would intrinsic redshift explain the observed time-dilation of SN1a supernovae? Or the increase in the apparent angular diameter of galaxies with redshifts of over z=1.6? Both observations are entirely consistent with an expanding universe.If the redshifts of these objects were due to a different cause, we need a mechanism by which Type 1a supernovae seem to have speeded up the duration of their explosions during the history of the universe and then slowed down again more recently, and a mechanism by which galaxies over a certain distance away (as measured by their apparent magnitude) seem to retain a similar structure to brighter galaxies, but get larger and larger in size the the more distant they are. Posted by SpeedFreek</DIV> Thanks for the homework assignment.  <div class="Discussion_UserSignature"> -KickLaBuka </div>

SpeedFreek · Aug 18, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>Thanks for the homework assignment.  Posted by KickLaBuka</DIV>Heheh, you are welcome!I only used these examples to show that there is a lot more evidence that the universe is expanding than just redshift. Redshifts are only one way to tell that the scale factor of the universe is changing, and they (in the vast majority of cases) confirm the expansion. Sure, we have a few observations that don't seem to fit, but seeing as the overwhelming majority of the other observations do fit, we have to assume the anomolous redshifts are being misinterpreted somehow.The highest redshift galaxies we see are very dim, as their light has been travelling for the longest time. But the size of these galaxies in the sky increases with redshift until the dimmest galaxies are almost twice the size of closer, a lot brighter galaxies.This would make perfect sense if those dimmest galaxies were actually relatively close to us when they emitted their light (as the angular diameter of an object shows how distant it was at the time - how big it looked).So if redshift is wrong, and the universe is not expanding, then we have some very large looking, dim and ghostly high redshift galaxies that must be closer to us than some very small looking, bright and low redshift galaxies and structurally, the galaxies look similar to each other. Or it would seem that all the galaxies in the universe were somehow shrinking but only until around 10 billion years ago.Either that, or the universe is expanding as the redshifts of galaxies seems to confirm. And then there is also the time-dilation of SN1a supernovae.... <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

bzannone · Aug 29, 2008

   If red shift does support expansion, how do galaxies collide if they should be moving away from each other, and if the rate of expansion is greater than the speed of light, is possible that these smaller, similar shaped galaxies are in fact our own galaxy? Also, could someone explain the "rogue black hole" concept? If a body is part of a gravitational system, how could it wander throughout that system?

SpeedFreek · Aug 30, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>   If red shift does support expansion, how do galaxies collide if they should be moving away from each other, and if the rate of expansion is greater than the speed of light, is possible that these smaller, similar shaped galaxies are in fact our own galaxy? Also, could someone explain the "rogue black hole" concept? If a body is part of a gravitational system, how could it wander throughout that system? Posted by bzannone</DIV>The expansion (whatever its nature) is very weak and gravity easily overcomes it. When the distance between 2 objects is so large that there is virually no gravitational attraction between them, the expansion causes the distance between those objects to increase. This leads to a scenario where galaxies cluster together due to gravity and within those clusters the galaxies can move around and towards each other, but the distance between the separate clusters increases due to expansion.How the rate of expansion works is that the further we look (outside of our super-cluster of gravitationally-bound galaxies), the faster a galaxy seems to be receding from us. This is easy to understand using a model of constant expansion where all of space is increasing in size at the same rate - all distances increase by the same factor over a given time.In this simple expansion example, in the same time it takes 1 billion light-years to increase to 2 billion light years, 10 billion will increase to 20 billion. So, after that given time, the closer object will have moved away only 1 billion light-years, but the more distant one has moved away by 10 billion light-years and thus seems to be receding faster. Of course, to that distant galaxy cluster, the clusters around it are only receding slowly and it is our cluster that is receding quickly. A simpler example:If you mark off metres on the ground, into the distance... 1,2,3,4,5... then stretch the ground to double its original size, the first mark will now be 2 metres away, the second 4, etc. So 1,2,3,4,5 doubles to 2,4,6,8,10. Say it only took 1 second to stretch the ground.So the first mark moved 1 metre in 1 second. It went from 1 to 2 metres away, in 1 second. The fifth mark, however, moved 5 metres in 1 second - it went from 5 to 10 metres away. The more distant mark receded at 5 times the speed of a closer one, but all the ground expanded at a constant rate. The mark is not moving over the ground, the ground is stretching around it. A mark that was 300,000 km away would have receded to 600,000 km, meaning it receded at 300,000 km/s - the speed of light. This is a very simple model to illustrate how the expanding universe causes distant galaxies to have the apparent recession speed faster than light, due to the same concept as above. Those galaxies are not moving through the universe faster than light though. What is happening is that the way the universe expands simply makes it look like they are receding faster than light. They would see our galaxy (or what was here before, billions of years ago) as receding from them faster than light too, but we know we aren't travelling through space faster than light, don't we? There is no reason to think that any of the distant galaxies we see might be our own galaxy. Remarkably, astronomers have checked for this, but ironically the idea that the distant galaxies have recession speeds faster than light actually prevents it. There was a possible scenario where the whole universe was actually a lot smaller than our observable universe. If the shape of the universe were such that light could circumnavigate it and return to where it started, then we might be seeing the same regions of space in different directions. Unfortunately, after looking in-depth for evidence of this, none has been found. It seems that our observable universe is all made up of unique galaxies, and we are not seeing the same galaxies in different places (except for the odd case of gravitational lensing).Due to the acceleration of the rate of expansion, even if the universe was shaped in such a way, the edges of our observable universe are now receding so fast that even light emitted there right now will never be able to reach us, let alone light that had to circumnavigate the universe. <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

bzannone · Sep 1, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>The expansion (whatever its nature) is very weak and gravity easily overcomes it. When the distance between 2 objects is so large that there is virually no gravitational attraction between them, the expansion causes the distance between those objects to increase. This leads to a scenario where galaxies cluster together due to gravity and within those clusters the galaxies can move around and towards each other, but the distance between the separate clusters increases due to expansion.How the rate of expansion works is that the further we look (outside of our super-cluster of gravitationally-bound galaxies), the faster a galaxy seems to be receding from us. This is easy to understand using a model of constant expansion where all of space is increasing in size at the same rate - all distances increase by the same factor over a given time.In this simple expansion example, in the same time it takes 1 billion light-years to increase to 2 billion light years, 10 billion will increase to 20 billion. So, after that given time, the closer object will have moved away only 1 billion light-years, but the more distant one has moved away by 10 billion light-years and thus seems to be receding faster. Of course, to that distant galaxy cluster, the clusters around it are only receding slowly and it is our cluster that is receding quickly. A simpler example:If you mark off metres on the ground, into the distance... 1,2,3,4,5... then stretch the ground to double its original size, the first mark will now be 2 metres away, the second 4, etc. So 1,2,3,4,5 doubles to 2,4,6,8,10. Say it only took 1 second to stretch the ground.So the first mark moved 1 metre in 1 second. It went from 1 to 2 metres away, in 1 second. The fifth mark, however, moved 5 metres in 1 second - it went from 5 to 10 metres away. The more distant mark receded at 5 times the speed of a closer one, but all the ground expanded at a constant rate. The mark is not moving over the ground, the ground is stretching around it. A mark that was 300,000 km away would have receded to 600,000 km, meaning it receded at 300,000 km/s - the speed of light. This is a very simple model to illustrate how the expanding universe causes distant galaxies to have the apparent recession speed faster than light, due to the same concept as above. Those galaxies are not moving through the universe faster than light though. What is happening is that the way the universe expands simply makes it look like they are receding faster than light. They would see our galaxy (or what was here before, billions of years ago) as receding from them faster than light too, but we know we aren't travelling through space faster than light, don't we? There is no reason to think that any of the distant galaxies we see might be our own galaxy. Remarkably, astronomers have checked for this, but ironically the idea that the distant galaxies have recession speeds faster than light actually prevents it. There was a possible scenario where the whole universe was actually a lot smaller than our observable universe. If the shape of the universe were such that light could circumnavigate it and return to where it started, then we might be seeing the same regions of space in different directions. Unfortunately, after looking in-depth for evidence of this, none has been found. It seems that our observable universe is all made up of unique galaxies, and we are not seeing the same galaxies in different places (except for the odd case of gravitational lensing).Due to the acceleration of the rate of expansion, even if the universe was shaped in such a way, the edges of our observable universe are now receding so fast that even light emitted there right now will never be able to reach us, let alone light that had to circumnavigate the universe. Posted by SpeedFreek</DIV>                       Ok, I got what your saying about the the universe being smaller than observed if light could circumnavigate it. I was under the impression that the expansion was a result of the Big Bang, if true, the expansion would be uniform in all directions outward from a central location, presumably the center of the universe. Is this just a too simplistic view? If not, then the rate that galaxies or clusters are receding from one another is irrelevant to the question of whether or not light observed from the direction of the event (B.B.) could be our own if we were or are moving through space faster than light. You posed the question, was it rhetorical, because I don't know that we are not travelling that fast through space (I did mention my ignorance?) Is that indeed an accepted demonstrable fact or is it one of those givens because theoretically nothing can move that fast? One more, if something only appears to travelling faster than light, then for all practical purposes, isn't it?

SpeedFreek · Sep 1, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>Ok, I got what your saying about the the universe being smaller than observed if light could circumnavigate it. I was under the impression that the expansion was a result of the Big Bang, if true, the expansion would be uniform in all directions outward from a central location, presumably the center of the universe. Is this just a too simplistic view? Posted by bzannone</DIV>Yes, I am afraid it is a simplistic view and we do not think there is a central location where the expansion is uniform in all directions. Or perhaps I should say that we are at that central location, and everything (outside of our cluster of gravitationally bound galaxies) is receding uniformly from us, in all directions! We don't think we are at the centre of the universe however, we think that the view would be the same wherever you put yourself in the universe. Whatever galaxy you are in, the distant galaxies recede from you uniformly in all directions.If you take my "stretching the ground" example, you should be able to see how this works, how any mark you choose to sit on will look like the centre of expansion. But if it is not clear, I will go a little further! Here is an explanation I used on another forum - it uses the principle from "stretching the ground", but puts it into three dimensions. Let's make a model. 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 apart with it, you get effects pretty much like how we think the universe expands. This is a very simplified view, but I hope it is a helpful one! If the whole thing expands and you cannot see an edge, it always looks like you are at the centre.  Replying to: <DIV CLASS='Discussion_PostQuote'>If not, then the rate that galaxies or clusters are receding from one another is irrelevant to the question of whether or not light observed from the direction of the event (B.B.) could be our own if we were or are moving through space faster than light. You posed the question, was it rhetorical, because I don't know that we are not travelling that fast through space (I did mention my ignorance?) Is that indeed an accepted demonstrable fact or is it one of those givens because theoretically nothing can move that fast? One more, if something only appears to travelling faster than light, then for all practical purposes, isn't it? Posted by bzannone</DIV>Yes, it was a rhetorical question, sorry about that.You mention light observed from the direction of the event (Big-Bang). Well, we are looking back towards earlier times whichever direction we look outwards. Every direction leads back towards the Big-Bang. Our observable universe stretches out to a distance (measured by the time that light has taken to reach us) of 13.7 billion (light) years in all directions. We are at the centre of an observable sphere of space 13.7 billion years in radius. The edge of that sphere represents the furthest back we can possibly see and the only thing we can see coming from there is the radiation left over when atoms formed (the Cosmic Microwave Background Radiation).The observable universe:Imagine the beginning of time. If there is light around, it will take time to reach you, but this is the beginning of time so no light has had time to move yet. Right at the beginning, your observable universe has no size at all! As time moves forward, any light that exists will move at the speed of light. Suddenly you can see a small distance all around you, as light starts coming in from different directions.After a year, you would be able to see 1 light-year in all directions. After 100 years therefore, your observable universe would be a sphere, 100 light-years in radius. After 13.7 billion years, your observable universe would be 13.7 billion light-years in radius, as you receive light that has been travelling for 13.7 billion years.If only it were that simple! The problem comes when considering that the universe is expanding and at the start our observable part of it was very small and was expanding incredibly fast, much faster than light. Also, light did not exist as an independant particle until around 370,000 years after the Big-Bang. Before that, photons were bound to other particles and atoms didn't exist as everything was very hot and mixed up!But at 370,000 years in, the universe had expanded and the temperature had cooled enough for atoms to form in a flash of light (when photons first moved freely throughout the universe). These photons filled the universe at that time, and we still receive these photons today. They are now stretched into microwaves (by the expansion of the universe) and are known as the Cosmic Microwave Background Radiation (CMBR).But as all this was happening, the universe was expanding. We measured how much those photons had been stretched and it told us how much bigger the universe is today, than it was when those photons were emitted. We estimate that, when the CMBR was emitted, our observable universe was 40 million light-years in radius.Hang on, didn't I earlier imply that, 370,000 years after the BB, our observable universe would be 370,000 light-years in radius? Well, that radius, based on the time that light takes to travel, is not actually a useful measure of distance at all! It is a measure of time elapsed only. When astronomers say the universe is 13.7 billion light-years in radius they are not giving you a distance through space, they are giving you a distance through time. Proper distance is a different thing entirely (although at distances closer to today, they are essentially the same). The CMBR photons we receive today have been travelling for 13.7 billion years, but they were emitted at a proper distance of only 40 million light-years away, all that time ago. The reason they have taken so long to reach us is that the universe is expanding, putting more distance in between photons and their eventual "targets". At the beginning, a point in space was right next to the point where our galaxy finally formed, but only 370,000 years later that point in space was 40 million light-years away - that's how fast the universe was expanding, early on.13.7 billion years later we receive those CMBR photons that were only emitted 40 million light-years away. And the real mind-bender is that we think that emission point is now over 46 BILLION light-years away. The edge of our observable universe, the most distant point from which we have received CMBR photons, is 46 billion light years away and continues to recede from us. That "edge", known as the surface of last scattering, was receding from this point in space at over 58 times the speed of light when those CMBR photons were emitted, it is still receding at around 3 times the speed of light today and we assume there are galaxies there now, but all we see is radiation emitted from there, long ago. The other mind-bender is that the whole universe is probably larger than our observable universe. After a fraction of a second, when our observable universe only had a radius of 10cm, there may well have been the same thing happening 20cm away. When the CMBR was emitted, and our observable universe was only 40 million light-years in radius, there might have been CMBR emitted 80 million light-years away, or much further away than that. Today, when we think our observable universe has a radius of 46 billion light-years and we assume that, as galaxies formed in these parts there would be galaxies throughout, there could be galaxies whose own observable part of the universe is totally separate from ours, galaxies that are 100s of billions of light-years away.Sorry for the incredibly long-winded post, but these are complicated concepts and even over-simplifying them takes a lot of space! This is a very basic summing up of the mainstream view, and hopefully it will help you understand the nature of your question, but if not, feel free to ask some more (I know I didn't answer all your questions)! If quoting this post, please edit it!<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>

derekmcd · Sep 1, 2008

One of my favorite papers by Lineweaver regarding all this: http://arxiv.org/abs/astro-ph/0305179 Scientific American also has a pretty lengthy article written by Lineweaver and Davis:http://www.sciam.com/article.cfm?id=misconceptions-about-the-2005-03Here's the paper the article is based off of:http://www.mso.anu.edu.au/~charley/papers/DavisLineweaver04.pdf Tons of easy to read and understand information in the two papers along with the article.  And enough math in the first paper to please the more rigorous minded individuals.    <div class="Discussion_UserSignature"> <div> </div> <div>"If something's hard to do, then it's not worth doing." - Homer Simpson</div> </div>

SpeedFreek · Sep 1, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>One of my favorite papers by Lineweaver regarding all this: http://arxiv.org/abs/astro-ph/0305179Scientific American also has a pretty lengthy article written by Lineweaver and Davis:http://www.sciam.com/article.cfm?id=misconceptions-about-the-2005-03Here's the paper the article is based off of:http://www.mso.anu.edu.au/~charley/papers/DavisLineweaver04.pdfTons of easy to read and understand information in the two papers along with the article.  And enough math in the first paper to please the more rigorous minded individuals.    Posted by derekmcd</DIV>Heh, "easy to read and understand information"... yes, I admit these recent posts of mine are a bit "all over the place", but all of it is based on my understanding of those second two links you posted. I had somehow missed that first paper you posted, I have now downloaded it and will be studying it intensely! Many thanks.  <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

derekmcd · Sep 1, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>Heh, "easy to read and understand information"... yes, I admit these recent posts of mine are a bit "all over the place", but all of it is based on my understanding of those second two links you posted. I had somehow missed that first paper you posted, I have now downloaded it and will be studying it intensely! Many thanks.  Posted by SpeedFreek</DIV>The easy to read comment was, in no way, a reflection on you and your posts.  You always explain it quite clear.  I just thought I would add the comment so folks don't automatically assume the papers are overly complication and shy away from giving them a good read.  <div class="Discussion_UserSignature"> <div> </div> <div>"If something's hard to do, then it's not worth doing." - Homer Simpson</div> </div>

SpeedFreek · Sep 1, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>The easy to read comment was, in no way, a reflection on you and your posts.  You always explain it quite clear.  I just thought I would add the comment so folks don't automatically assume the papers are overly complication and shy away from giving them a good read.  Posted by derekmcd</DIV>Well, I was looking up at my "wall of post" above and thinking it looked a bit intimidating myself, when you posted, so I apologise for implying that you were implying it too! The first paper is the most comprehensive summing up I have seen so far. I can't believe its been out there for 5 years and this is the first time I have seen it!The second link is the best simplified explanation on the internet, in my opinion, and the paper it is based on is a classic.  <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

KickLaBuka · Sep 2, 2008

I'm working on your question about "aparent time-dialation" with "distant" supernova, Speed.  Bear with me.  But let me reiterate, YOU'RE WRONG ABOUT EXPANSION.  <div class="Discussion_UserSignature"> -KickLaBuka </div>

SpeedFreek · Sep 2, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>I'm working on your question about "aparent time-dialation" with "distant" supernova, Speed.  Bear with me.  But let me reiterate, YOU'RE WRONG ABOUT EXPANSION.  Posted by KickLaBuka</DIV>Don't forget the angular diameter - redshift distance relationship of galaxies too. Once you understand this concept, it is hard to argue against redshift showing us that the universe is expanding, unless you also introduce new physics. You need a mechanism by which the dimmest galaxies are larger or closer than much brighter ones, simply put. "Intrinsic redshift" as you refer to it, will struggle to explain this one. Observational Cosmology: World Models and Classical Tests And it's not about me being wrong, as I simply explain the current mainstream view in cosmology. <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

KickLaBuka · Sep 2, 2008

I'm not complete on my understanding because I've never spoken with anyone from the EU community.  It would have been nice to have more time, but I feel it's important to adjust the conversation.  This is what I can gather, and we can poke at the holes to find the solutions.  Hopefully I don't bring in any falsehoods to the Electric name, because I'm not involved with their organization beyond some simple studying and some basic courses.  All of everyone's observations will be key in understanding its finer points and determining actual current density and voltage. Stars or Celestial Bodies:  The current density is higher at the arms of galaxies because they are moving faster through the electric plasma.  Stars in the path of intense Birkeland Currents also effect the charge for the same reason.  Those spinning faster also have more impact on the stars’ charge because of trigonometric properties of charged spheres spinning.  All in all:  Charge in motion.  Spin is a common effect of the interaction between electric and their resultant magnetic fields.  These conditions make stars of the same size more luminous or less luminous.  When a star spins fast enough or begins a tighter turn around the galaxy or get's in the path of strong currents, the star gathers enough charge in its double layer where it reaches a maximum capacitance; the double layer begins to push its limits at a comfortable distance from the iron shell.  Double Layer:  double layer is the place where the positive ions from the stars’ surface can accumulate due to atmospheric conditions, and where the negative ions from space can seek out.  Bright stars have an overabundance of these charges.  The earth’s double layer is small, but visible during the day.  Supernova:  The double layer presses at the poles because the electric field is weaker due to its rotation.  The charge also likes the straight magnetic field lines to travel between on their journey to spread out from the overabundance of charge.  The charge makes a downward funnel at the poles.  There comes a critical point where an electrostatic discharge occurs between the surface voltage and the double layer, and that bolt goes straight through the axis and blows it apart.  charges and debris find a more steady state than before due to increased surface area. Replying to: <DIV CLASS='Discussion_PostQuote'>Don't forget the angular diameterPosted by SpeedFreek</DIV>  The size of these galaxies in the sky increases with redshift until the dimmest galaxies are almost twice the size of closer, a lot brighter galaxies.  Charged objects that are spinning create magnetic field lines that make a doughnut shape around the charge.  If it’s spinning clockwise, those magnetic field lines go out the top and turn back down the sides.  If there are lots of charged objects spinning, those magnetic field lines would find a happy medium where they can share similar forces from other stars’ electric fields.   Systems become galaxies and stronger field lines make tigher packed systems.  I believe the question of why dimmer galaxies are bigger is a no brainer.  Time dialation:  This is what has been gnawing at me for this time.  It is observed that weaker overall galaxies with a high intensity star that explodes have slower dimming supernova events than stronger galaxies’ supernova events.  Is this the observation?  Is there anymore information about these?  I saw the light curve over time for the two speeds of novae, and the slow ones are pretty interesting; surely not a “stretch” from flying away faster, but somewhat similar to the “fast” novae in the brighter galaxies.  I wonder how the weaker field lines distribute the charge during such an event.  These observations over time must be amazing. <div class="Discussion_UserSignature"> -KickLaBuka </div>

SpeedFreek · Sep 3, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>The size of these galaxies in the sky increases with redshift until the dimmest galaxies are almost twice the size of closer, a lot brighter galaxies.  Charged objects that are spinning create magnetic field lines that make a doughnut shape around the charge.  If it’s spinning clockwise, those magnetic field lines go out the top and turn back down the sides.  If there are lots of charged objects spinning, those magnetic field lines would find a happy medium where they can share similar forces from other stars’ electric fields.   Systems become galaxies and stronger field lines make tigher packed systems.  I believe the question of why dimmer galaxies are bigger is a no brainer. Posted by KickLaBuka</DIV>Remember, the angular size of galaxies decreases with redshift until a certain point around redshift z~1.4 and then with increasing redshift we see increasing angular size. Using our current model, the size of galaxies gets smaller out to around 9 billion light years away (light-travel time), and then more distant galaxies get larger out to the most distant we have seen at around 12.7 billion light years away (light-travel time). With the current mainstream model, the Lambda-CDM concordance model, this is easily explained, as those most distant galaxies were actually closer to us when they emitted their light than the brighter galaxies, as they emitted their light when the universe was a lot smaller than it was when the brighter galaxies emitted their light.If your explanation is to hold, you need to explain why your electrical effects stopped affecting the size of galaxies 9 billion years ago, why we see the increasing angular size of galaxies only before that time.With the mainstream model, a galaxy at z~7 was only 3.5 billion light years away, 12.7 billion years ago, but a galaxy with a redshift of z~1.4 was 5.7 billion light years away, 9 billion years ago. We receive their light at the same time, due to the expansion of the universe putting more distance between those photons and their eventual target. Simple. <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

derekmcd · Sep 3, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>Remember, the angular size of galaxies decreases with redshift until a certain point around redshift z~1.4 and then with increasing redshift we see increasing angular size. Using our current model, the size of galaxies gets smaller out to around 9 billion light years away (light-travel time), and then more distant galaxies get larger out to the most distant we have seen at around 12.7 billion light years away (light-travel time). With the current mainstream model, the Lambda-CDM concordance model, this is easily explained, as those most distant galaxies were actually closer to us when they emitted their light than the brighter galaxies, as they emitted their light when the universe was a lot smaller than it was when the brighter galaxies emitted their light.If your explanation is to hold, you need to explain why your electrical effects stopped affecting the size of galaxies 9 billion years ago, why we see the increasing angular size of galaxies only before that time.</DIV>The reason for this phenomena is due to the accelerated expansion of the universe.  About 4 billion years ago, the universe became dark energy dominate.  Essentially, the first 9 billion years, the expansion was slowing down.  For a brief time, the slowing of the expansion stopped and became constant until the universe eventually began to accelerate.  Any galaxy that emitted it's light less than 4 billion years ago that is reaching us today is under the influence of accelerated expansion.  In other words, the distance based on the angular diameter will not keep up with the distance based on redshift when the light was emitted up to 4 billion years ago as it is further away that it would appear due to acceleration.   The longer the light has had to travel after 4 billion years, the faster it will catch back up to the distance based on redshift.I think that makes sense. Replying to: <DIV CLASS='Discussion_PostQuote'>With the mainstream model, a galaxy at z~7 was only 3.5 billion light years away, 12.7 billion years ago, but a galaxy with a redshift of z~1.4 was 5.7 billion light years away, 9 billion years ago. We receive their light at the same time, due to the expansion of the universe putting more distance between those photons and their eventual target. Simple. Posted by SpeedFreek</DIV>I'm sure an innocent mistake on your part, but your distance of 3.5 and 5.7 are the angular size distances which aren't the actual distance from us when the light was emitted.  I think you meant .77 and 4.6 repsectively. <div class="Discussion_UserSignature"> <div> </div> <div>"If something's hard to do, then it's not worth doing." - Homer Simpson</div> </div>

SpeedFreek · Sep 3, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>The reason for this phenomena is due to the accelerated expansion of the universe.  About 4 billion years ago, the universe became dark energy dominate.  Essentially, the first 9 billion years, the expansion was slowing down.  For a brief time, the slowing of the expansion stopped and became constant until the universe eventually began to accelerate.  Any galaxy that emitted it's light less than 4 billion years ago that is reaching us today is under the influence of accelerated expansion.  In other words, the distance based on the angular diameter will not keep up with the distance based on redshift when the light was emitted up to 4 billion years ago as it is further away that it would appear due to acceleration.   The longer the light has had to travel after 4 billion years, the faster it will catch back up to the distance based on redshift. I think that makes sense. Posted by derekmcd</DIV>Dark energy and the accelerating expansion have nothing to do with the increase in the angular size of galaxies over z~1.6 I'm afraid. The increase in angular size is purely a function of the fast rate of expansion to begin with and would be apparent in a purely decelerating universe. It is to do with the hubble radius and how it recedes from us over time, so accelerating expansion might have an effect on the point where angular size-redshift relationship reverses, but the increase in size for objects outside of our hubble radius would remain even with no acceleration. The acceleration started relatively recently, but the increase in apparent angular size ends at around z=1.6 which is over 9 billion years ago, and begins as far back as we can see. Would acceleration that didn't start happening until billions of years after the increase in angular diameter stops, affect the relationship, since light never overtakes light? The following is from another of my long posts (sorry):  Consider the distance where an object (or a co-moving coordinate) is apparently receding at the speed of light. As the rate of expansion (or more accurately, the change in the scale factor of the background metric) was very fast in the early universe, this means that the distance at which a co-moving coordinate was apparently receding at c was close to this point in space. If the expansion rate had remained constant, then so would the distance at which a co-moving coordinate was receding at c would have remained constant. But the rate of expansion decelerated and therefore the distance at which a co-moving coordinate was apparently receding at c became larger. The rate of expansion continued to slow, and after something over 100 million years, the earliest galaxies formed. The observable universe was something around 2 billion light years in radius at that time. We have seen dim blobs that might be these galaxies, but the oldest, dimmest, most distant galaxy we have reliable measurements for emitted its light around 800 million years after the Big-Bang, it has a redshift just under z=7 and is estimated to have been 3.5 billion light years away when it emitted its light. Now lets look at a galaxy at redshift z=3. This (much brighter) light was emitted when the universe was 2.2 billion years old, 11.5 billion years ago when that galaxy is estimated to have been 5.3 billion light years away. Now we move closer still to redshift z=1.4 and here is where we find the galaxies that are apparently receding at the speed of light – that is, they were receding at the speed of light when they emitted the light we are now seeing. The light we are seeing was emitted when the universe was around 4.6 billion years old, just over 9 billion years ago. These galaxies are estimated to have been 5.7 billion years away when they emitted the light we see, and what is more, they are the most distant objects we have seen in the universe! Let me say that again. Objects that are apparently receding at the speed of light are the most distant objects we have actually seen. Let me explain what I mean by this... We use measurements of a galaxy's angular diameter (how big the object actually looks in the sky) to determine how far away they were when they emitted the light we are now seeing. This makes sense, as you always see any object at the distance it was when the light left it, regardless of whatever it does or however it moves afterwards. Anyway, that is how astronomers determine the distance a galaxy was from us when it emitted the light we are now seeing (of course, they also have to determine what the galaxy's actual or absolute size was to do this, and this is a whole other subject unto itself!). We find that the most distant galaxies by angular size are the ones that are apparently receding at c, and yet we see light from more distant (in time) galaxies that are dimmer and more redshifted and yet those galaxies have increasing angular diameter the further we look in that direction. Lets look at the figures (The first line is the CMBR or surface of last scattering) I took from Ned Wrights cosmology pages. Redshift____Distance then____Time since emission z=1089_____42 million ly_____13.7 billion years ago z=7________3.5 billion ly_____12.8 billion years ago z=3________5.3 billion ly_____11.5 billion years ago z=1.4______5.7 billion ly_______9 billion years ago z=1________5.4 billion ly______7.7 billion years ago The key thing to remember is that light never overtakes light. If you look at those figures above and also remember that we received all those photons at pretty much the same time you will find that: Photons were emitted 3.5 billion light years away, 12.8 billion years ago. 1.3 billion years later, photons were emitted 5.3 billion light years away and if light never overtakes light then those older photons must have been "moved away by the expansion" to that distance (i.e the older photons would have been passing those "closer" galaxies). 2.5 billion years later still, photons were emitted 5.7 billion years away and so our older photons must have "moved away" that far by then. And all those photons reached us at the same time.So the light from that redshift=7 galaxy was receding from us (as it made its way towards us) from emission at 12.8 billion years ago until it passed the point where objects were apparently receding at lightspeed from us, 9 billion years ago. All light we receive that was emitted more than 9 billion years ago was effectively moving away from us whilst it made its way towards us until it passed that point 5.7 billion light years away that was receding at c and then the light took another 9 billion years to reach us after that through a universe where the rate of expansion was levelling out and starting to accelerate again. This is all shown on the space-time diagrams on pages 3 and 11 of the Lineweaver-Davis: "Expanding Confusion" paper. The line representing our light-cone shows the distance the photons we receive were when they were emitted.This is the reason for the increase in apparent angular diameter of distant galaxies. Not only were they receding superluminally when they emitted their light, but the distance to their light was increasing faster than light for a few billion years after wards. Their light had receded to 5.7 billion years away before the rate of expansion slowed enough for the light to start making real progress towards us, passing galaxies that were receding from us slower than light.From Observational Cosmology: World Models and Classical Tests "It is interesting that, for any given positive value of q0, there exists a minimum in the q(z) relation for any linear size; things at higher redshift look bigger again because they were quite nearby when the light was emitted. For q0=1/2, the angular diameter goes through a minimum at z=5/4."  Replying to: <DIV CLASS='Discussion_PostQuote'>I'm sure an innocent mistake on your part, but your distance of 3.5 and 5.7 are the angular size distances which aren't the actual distance from us when the light was emitted.  I think you meant .77 and 4.6 respectively. Posted by derekmcd</DIV>Sorry, but the angular size distance is the actual distance from us, the proper distance, that the object was when it emitted the light we are now seeing.  Your figures are for the age of the universe at emission - .77 billion years old at z=7 and 4.6 billion years old at z=1.4.But I think you must be misunderstanding me, as I am sure I have seen you post The Distance Scale of the Universe before. <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

KickLaBuka · Sep 5, 2008

Sorry guys,But Mr. Tolman had no right basing his formulations off of hubble law, because hubble law is not allowed to be used as a measure of distance.  Further, using (1+z) = the factor that space has stretched by, as well as (1+z) = the factor that clocks have sped up since then, as well as (1+z)(1+z) = surface brightness dropoff.  If he needed it, Mr. Tolman would put in another (1+z) for himself, but it turns out multiplying these mistakes (1+z)(1+z)(1+z)(1+z) was all he needed to "prove" the universe is expanding.  Common guys.  Things for you change around 1 because that's called a parabola and your math makes it happen there.Any chance I can get you to tell us exactly what the x and y axis formulas are?  Cause don't you use (1+z) in there for your angular diameters too?  So in short, there is no need for electricity to explain such a ridiculous graph.  And it's science's responsibility to gather information at the basic level, and THEN find corellations.  Not keep adding factors of (1+z) until we get something that goes along with your theory.I don't mean to be rude, but if this is the basis for acceleration the astronomy community has laid out, it doesn't deserve to be called a science.  At best, it's "fun with parabolas."   <div class="Discussion_UserSignature"> -KickLaBuka </div>

SpeedFreek · Sep 5, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>I don't mean to be rude, but if this is the basis for acceleration the astronomy community has laid out, it doesn't deserve to be called a science.  At best, it's "fun with parabolas."   Posted by KickLaBuka</DIV>You obviously don't understand how our observations fit with those "parabolas" then. If you want the formulas for the axes, you will find them all here and here As for angular diameter, it is a simple set of observations. We found through observation that the dimmer the galaxy, the higher the redshift and the smaller the apparent angular size of the galaxy. But then we found that as galaxies get really dim and highly redshifted, the apparent angular size gets larger again. These are the observed relationships between the galaxies we see. Those "parabolas" are the averaged curves that best fit all the observations. Simple. <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

KickLaBuka · Sep 5, 2008

your observations have built-in multipliers, do they not?  You can't guess the angular size until you have already guessed the distance, right?  I understand my last email was a bit rash and disrespectful.  I do appreciate all of your guys' help and I never would have gotten here if it hadn't been for your teaching.  But I'm here also to explain how things went wrong, hoping that science will get better.  <div class="Discussion_UserSignature"> -KickLaBuka </div>

SpeedFreek · Sep 5, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>your observations have built-in multipliers, do they not?  You can't guess the angular size until you have already guessed the distance, right?  Posted by KickLaBuka</DIV>The multiplier you refer to is the scale factor of the universe since emission. All the observations will, of course, make sense only when considered in the context of the scale factor. Without it, we have to account for all sorts of strange phenomena like, for instance, galaxies in the early universe being of a similar structure but much larger (in absolute size) than galaxies are today, and decreasing in absolute size only for a certain length of time, and supernovae lasting for shorter and shorter durations as time progresses.We do not have to guess the apparent angular diameter, as it is apparent, and that is what we are talking about - the size we see these objects as (we do, however, have to guess the absolute angular diameter). But if dimness and size are an indicator of distance at emission, why are the dimmest galaxies larger than much brighter ones? Do you actually understand what z represents?  <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

KickLaBuka · Sep 5, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>Do you actually understand what z represents?  Posted by SpeedFreek</DIV> I am under the impression that it represents the wavelength difference between what you see and what you expect to see from the hydrogen line, divided by the expected hydrogen line wavelength.  This gives you z right?  Would you list all of the places that Z is used and in their formulas?  You're right.  What you say makes me think z has become something much much more.  If you would take the time, I would be much obliged. <div class="Discussion_UserSignature"> -KickLaBuka </div>

SpeedFreek · Sep 5, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>I am under the impression that it represents the wavelength difference between what you see and what you expect to see from the hydrogen line, divided by the expected hydrogen line wavelength.  This gives you z right?  Would you list all of the places that Z is used and in their formulas?  You're right.  What you say makes me think z has become something much much more.  If you would take the time, I would be much obliged. Posted by KickLaBuka</DIV>Well, of course you are correct that z represents shift in an objects spectrum, but as you correctly suspect it has become something much more. The mainstream view is that cosmological redshift is caused by the change in the scale factor of the universe, the amount the universe has expanded, during the time that the light was travelling. Our other observations tie into this scale factor too, assuming that cosmological redshift represents expansion.Simply put: The universe is now twice as large as it was at z=1. The universe is now 8 times as large as it was at z=7. The universe is now 1089 times as large as it was at z=1088. (1 + z).The durations of type 1a supernovae correlate with the scale factor too, these "standard candles" that always seem to burn for the same duration at a given distance, well their duration increases along with z. And I have gone into great depth already as to how the angular size-redshift(z) relationship works. It all points to expansion. I don't know enough to myself list all the places or formulas where z is used, but I can give you some pages to start you off.http://en.wikipedia.org/wiki/Redshifthttp://en.wikipedia.org/wiki/Angular_diameter_distancehttp://en.wikipedia.org/wiki/Angular_size_redshift_relationas well as the links I earlier posted.    <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

KickLaBuka · Sep 5, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>We do not have to guess the apparent angular diameter, as it is apparent, and that is what we are talking about - the size we see these objects as. posted by SpeedFreak</DIV> Thank you for helping to explain the angular diameter measurement.  The size we see these objects as.  I'm guessing you mean aparent is the number of arc seconds that the object takes to pass a fixed (to earth) point in a telescope.  So from arc angle, how do you get arc length?  You need a distance to the object.  Two guesses:  using parallax angles when the earth is at two sides of the sun.  That distance from month to month is known, and you witness the movement of the galaxies to those in the background, assuming these are fixed and move over the course of millions of years.  But from what I can gather about parallax angles, these things are just too far for the earth’s perspective to make a difference.  This causes any error to skyrocket the results.  The second guess is the arc angle and lensing in the telescope for distance. <div class="Discussion_UserSignature"> -KickLaBuka </div>

SpeedFreek · Sep 5, 2008

Yup, that's right, you need a distance. A combination of apparent luminosity, redshift and angular size, based on the cosmological model that best fits the largest range of observations with the least error. <div class="Discussion_UserSignature"> _______________________________________________ SpeedFreek </div>

KickLaBuka · Sep 5, 2008

Replying to: <DIV CLASS='Discussion_PostQuote'>Yup, that's right, you need a distance. A combination of apparent luminosity, redshift and angular size, based on the cosmological model that best fits the largest range of observations with the least error. Posted by SpeedFreek</DIV> The least error if we assume the universe is expanding.  If we don't assume that, then these direct observations are all we know. <div class="Discussion_UserSignature"> -KickLaBuka </div>

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