michel123456 Posted January 17, 2015 Posted January 17, 2015 Yes correct but..... is that what we are observing?
Mordred Posted January 17, 2015 Posted January 17, 2015 We observe the image you posted. You calculate the proper position
michel123456 Posted January 18, 2015 Posted January 18, 2015 We don't observe a wall of galaxy clusters in the deep universe.
Mordred Posted January 18, 2015 Posted January 18, 2015 Of course not the image you showed is no where near precise. It's simply a tool to aid understanding not an exact map. Its simply showing that galaxies are closer together the further you look back in time. 1
michel123456 Posted January 18, 2015 Posted January 18, 2015 Of course not the image you showed is no where near precise. It's simply a tool to aid understanding not an exact map. Its simply showing that galaxies are closer together the further you look back in time. Can you provide evidence of this? Some data?
Mordred Posted January 19, 2015 Posted January 19, 2015 (edited) http://arxiv.org/pdf/astro-ph/0402278v1.pdf[/url Here is a dissertation specifically on expansion. This calculator will allow you to see the expansion history yourself. It can calculate redshift distance now distance then evolution of the Hubbles sphere and observable universe etc Etc open column selections to choose. Number of steps for row control. http://www.einsteins-theory-of-relativity-4engineers.com/LightCone7/LightCone.html http://cosmocalc.wikidot.com/lightcone-tutorial http://cosmocalc.wikidot.com/lightcone-userguide As far as my proving the most proven model to observational evidence model to date LCDM. There is no need for me to prove the concordance model. There is tons of supporting evidence. The Planck datasets are in strong agreement with LCDM http://www.cosmos.esa.int/web/planck/publications tons of datasets there for ya Edited January 19, 2015 by Mordred
michel123456 Posted January 19, 2015 Posted January 19, 2015 (edited) I don't see anywhere data about distance being smaller between far away galaxy clusters. Maybe it is hidden somewhere inside the impressive planck dataset? Edited January 19, 2015 by michel123456
StringJunky Posted January 19, 2015 Posted January 19, 2015 I don't see anywhere data about distance being smaller between far away galaxy clusters. Maybe it is hidden somewhere inside the impressive planck dataset? If the universe is expanding now, it's pretty clear that if we reverse what has happened, the galaxies will have been closer together in the past.
michel123456 Posted January 19, 2015 Posted January 19, 2015 If the universe is expanding now, it's pretty clear that if we reverse what has happened, the galaxies will have been closer together in the past. This argument you can find thousand times over the Internet. What I ask for is a corroborating evidence. An astronomical measurement of smaller distances between far away galaxies. Data. 1
imatfaal Posted January 19, 2015 Posted January 19, 2015 This argument you can find thousand times over the Internet. What I ask for is a corroborating evidence. An astronomical measurement of smaller distances between far away galaxies. Data. I get what you are asking for now - and it seems totally reasonable. I have started a trawl - because I had no memory of such information that I have previously encountered. First off I wanted to check how possible it was to answer the question. At high redshift - ie way way back in the galactic past there were now galaxies; say at z=11 there is/was just the hot plasma that gives/gave off the cosmic background radiation. So we need to go back far enough for expansion to be noticeable - but not so far that the makeup of the universe was significantly different (otherwise the density of galaxies would be incommensurable) http://arxiv.org/abs/1404.2844 this paper would make me think that even at relatively low red shifts the propensity of galaxies to form differently and at different rates would make the comparison meaningless. But I am intrigued and will continue to look
Mordred Posted January 20, 2015 Posted January 20, 2015 Have you looked at the calculator? You can graph the expansion history distance now and distance then Here this might be clearer http://www.ifa.hawaii.edu/info/press-releases/flows/ http://arxiv.org/abs/1306.0091. This is local data group The others I located require software example http://supernova.lbl.gov/union/ I'll keep looking
michel123456 Posted January 20, 2015 Posted January 20, 2015 Wonderful Mordred. Your link to the video is formidable! http://irfu.cea.fr/cosmography However, I don't see evident signs of concentration of clusters as a function of distance.
JohnSSM Posted January 21, 2015 Posted January 21, 2015 Wonderful Mordred. Your link to the video is formidable! http://irfu.cea.fr/cosmography However, I don't see evident signs of concentration of clusters as a function of distance. That video is just awe inspiring...Finally someone used 3d modelling that shows vectors and space time g flow...why we cant do the same thing on smaller scales to show the geometry of GR in action for a solar system is puzzling... The flow into the zones of much mass in red, slows down and becomes more compact...the flow out of the blue zones of little mass, is faster and more spread out in comparison...Does that mean you could travel faster out of a void, than you could into a black hole, using the same energy?
michel123456 Posted January 21, 2015 Posted January 21, 2015 I don't even recognize space expansion in this video. I see much more complicated moves.
Mordred Posted January 21, 2015 Posted January 21, 2015 (edited) The problem is finding datasets that are easily related to. I could post numerous articles with datasets such as this one http://berkeley.edu/news/media/releases/2007/07/perlmutter-team.pdf but would it help you? It is a dataset supporting and constraining systematic errors. However the paper is not easily understood. Papers like this are easily found. However visualization of expansion from this is not an easy task (Ps that's one of the reasons Jorrie built the lightcone calculator in my signature) I've been scouring the internet for several days looking for the easy to relate to articles etc with the data sets included. Not as easy as one might think most require software installations to use. Speaking of videos you guys will love this one. http://www.mpa-garching.mpg.de/galform/virgo/millennium/ this took incredible supercomputer time over 3 months to generate. Note these two videos is a 100% simulated universe to test out model LCDM http://m.youtube.com/watch?v=NjSFR40SY58 Edited January 21, 2015 by Mordred
imatfaal Posted January 21, 2015 Posted January 21, 2015 (edited) I don't even recognize space expansion in this video. I see much more complicated moves. Modred can check my sums - but those distances in the video would mean a redshift of around about 0.01 to 0.02. That is strictly very local in universal terms Edited January 21, 2015 by imatfaal Correcting figures
GeneralDadmission Posted January 30, 2015 Posted January 30, 2015 Why would expansion not be considered an aspect of gravitation? Could the BB not have been considered to simply regulate observation of expansion to the point we can only observe expansion along our universes trajectory?
Mordred Posted January 30, 2015 Posted January 30, 2015 (edited) The metrics of expansion and cosmology is an ideal gas gravity contributes to the positive pressure, while the cosmological attributes to the negative pressure. Gravity is an attraction only, there is no anti gravity. http://cosmology101.wikidot.com/redshift-and-expansion http://cosmology101.wikidot.com/universe-geometry every contributor particles,radiation matter etc has an equation of state that correlates its energy density to pressure contribution. http://en.m.wikipedia.org/wiki/Equation_of_state_(cosmology) This includes particles/antiparticles The only difference between the two is the charge. Their EoS is identical. Edited January 30, 2015 by Mordred
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