DimaMazin Posted November 26, 2014 Share Posted November 26, 2014 yes, maybe I was supposed to say that I'm happy with yours answers. probably I'm burn some processors to lift up this question here.. Relativity says that ether doesn't exist. Big bang theory says that ether expands. I don't see a conformity. -1 Link to comment Share on other sites More sharing options...
Mordred Posted November 26, 2014 Share Posted November 26, 2014 The big bang says nothing about the ether. What it truly entails is the standard model of particles+ the thermodyanamic laws + plus measurement data. If you were to study particle thermodynamic symmetry breaking in conformance to the ideal gas laws. With either the SO(5) or the SO(10) standard model in terms of cosmology history and applications in terms of the various epochs and phase transitions you would develop a solid understanding of big bang nucleosynthesis. This prediction is one of the single most least understood and most missed detail in the predictive ability of BBN as set forth by the concordance LCDM model. for further clarity see my web site on my Sig. Various technical manuals with the concordance model is provided there. In particular the two articles on early universe particle physics and thermodynamicd Link to comment Share on other sites More sharing options...
DimaMazin Posted November 26, 2014 Author Share Posted November 26, 2014 The big bang says nothing about the ether. What it truly entails is the standard model of particles+ the thermodyanamic laws + plus measurement data. Far galaxies were nearer(agreeing with big bang theory) therefore light from them should arrive earlier(agreeing with relativity) than it makes. Apples aren't oranges. We can see galaxies at distance 13.7 billions light years(it is an instant of light emission) , this is age of our universe. When did they have time to escape to this distance?Or do you think ether has carried away us? -1 Link to comment Share on other sites More sharing options...
MigL Posted November 26, 2014 Share Posted November 26, 2014 Say a car is 100m away from you. And say that car is moving at 100m/s away from you. After one second it is no longer 100m distant, but 200m distant. The universe is 13.7 bil yrs old, but it has been expanding ( at variable rates ) since then. Do you see how it works Dima ? Link to comment Share on other sites More sharing options...
Strange Posted November 26, 2014 Share Posted November 26, 2014 Far galaxies were nearer(agreeing with big bang theory) therefore light from them should arrive earlier(agreeing with relativity) than it makes. Apples aren't oranges. We can see galaxies at distance 13.7 billions light years(it is an instant of light emission) , this is age of our universe. When did they have time to escape to this distance?Or do you think ether has carried away us? (Actually, the furthest galaxy seen so far is about 13.3 billion light years away.) At the risk of confusing you further, those galaxies were only about 4 billion light years away when that light was emitted, and are now about 40 billion light years away. Link to comment Share on other sites More sharing options...
DimaMazin Posted November 26, 2014 Author Share Posted November 26, 2014 Say a car is 100m away from you. And say that car is moving at 100m/s away from you. After one second it is no longer 100m distant, but 200m distant. The universe is 13.7 bil yrs old, but it has been expanding ( at variable rates ) since then. Do you see how it works Dima ? No. I see the car on distance of 100m.Because light travels at "c" in my frame. (Actually, the furthest galaxy seen so far is about 13.3 billion light years away.) At the risk of confusing you further, those galaxies were only about 4 billion light years away when that light was emitted, and are now about 40 billion light years away. We should see those galaxies only at 4 billion light years away. Link to comment Share on other sites More sharing options...
Endy0816 Posted November 26, 2014 Share Posted November 26, 2014 The light itself is impacted by the expansion. Basically the distance the light has to travel increases, while its own speed remains constant. You can think of it as a treadmill. If you move forward at 5m/s but are moved backwards at 4 m/s you are going to only advance at 1m/s. Link to comment Share on other sites More sharing options...
DimaMazin Posted November 26, 2014 Author Share Posted November 26, 2014 The light itself is impacted by the expansion. Basically the distance the light has to travel increases, while its own speed remains constant. You can think of it as a treadmill. If you move forward at 5m/s but are moved backwards at 4 m/s you are going to only advance at 1m/s. Agen stream of ether. Link to comment Share on other sites More sharing options...
Strange Posted November 26, 2014 Share Posted November 26, 2014 We should see those galaxies only at 4 billion light years away. Why? The light has taken 13.3 billion light years to get here (because of the expansion of space). Link to comment Share on other sites More sharing options...
Endy0816 Posted November 26, 2014 Share Posted November 26, 2014 (edited) Agen stream of ether. The light or whole superclusters aren't actually being moved though. The distance alone is all that is increasing. I've yet to find a really good analogy to use for this. You can imagine adding a meter, 10 meters, 100 meters, and then a kilometer between you and something you are looking at, that is probably the simplest thought experiment. Still not accurate for actual expansion but gives a sense of things anyways. Edited November 26, 2014 by Endy0816 Link to comment Share on other sites More sharing options...
DimaMazin Posted November 26, 2014 Author Share Posted November 26, 2014 Why? The light has taken 13.3 billion light years to get here (because of the expansion of space). Well. Link to comment Share on other sites More sharing options...
michel123456 Posted November 26, 2014 Share Posted November 26, 2014 Say a car is 100m away from you. And say that car is moving at 100m/s away from you. After one second it is no longer 100m distant, but 200m distant. The universe is 13.7 bil yrs old, but it has been expanding ( at variable rates ) since then. Do you see how it works Dima ? My question is the following: You look at the West and observe far away galaxies 12 billion years from us. You look at the East and observe far away galaxies again. As much you look in the past the more the galaxies are far away from each other (the West from the East) And suddenly the BBT tells us that the West and East galaxies, instead of being diametrically far away from each other, were together. That is difficult to swallow. Link to comment Share on other sites More sharing options...
Strange Posted November 26, 2014 Share Posted November 26, 2014 (edited) And suddenly the BBT tells us that the West and East galaxies, instead of being diametrically far away from each other, were together. That is difficult to swallow. Because the distance between them has increased. In the past they were closer together. That doesn't seem too hard to understand. Edited November 26, 2014 by Strange Link to comment Share on other sites More sharing options...
Mordred Posted November 27, 2014 Share Posted November 27, 2014 (edited) Here is a way to think of the distance light can travel and the size of the observable universe. First for clarity we need to define two regions. The Hubble sphere and the cosmological event horizon. The Hubble sphere is basically the distance light can travel multiplied by the age of the universe. The ccosmological event horizon represents the size of the observable universe. This is the age of the universe plus speed of light plus expansion The latter does not simply add up as expansion rates is exponenential. To keep extremely simple we will apply some numbers. Take a 12" ruler set 1" as one light year. In the former each year represents one year of light travel so the Hubble sphere equals the age of the universe in light years. The the case of expansion however it gets more complex. Take the same ruler look ahead one light year. Now each measurement point in that ruler has increased in distance by approx 70 km/Mpc/sec ( Hubble constant=rate of expansion at a specific moment in time constant everywhere only at a specified moment in time) Now what does this do.. The light has travelled one light year. However the distance between us and the light path is increasing as well as the distance already travelled So locally light has no problem travelling faster than the Hubbles constant. It's far faster than 70 km/Mpc/sec. However the distance between its current location and us also increases. This means it will take longer to close that added distance ( the FLRW metric takes this into account) However the space already travelled is also increasing. For the light path already travelled this has no effect other than to the observer. This increase of distance causes the wavelength of light to stretch (cosmological redshift)(part of the FLRW metric) As a result of expansion the cosmological event horizon is larger than the Hubble sphere. The cosmological event horizon is roughly 46 Gly in radius the age of the universe is roughly 13.78 years the Hubble sphere equals the age in Gly hope this helps if not my signature has a calculator which I assisted in development. As well as numerous articles under misconceptions. I would recommend reading Redshift and expansion which I wrote under the cosmology101 signature link as well as the Cosmological horizons article under misconceptions by Brian Powell a good friend and colleague of mine. He has years of exp answering forum questions and he wrote that article as a time saver. (I proof read and added some advise) (I also proof read his dissertation more on the grammar as his math ability far exceeds mine) http://cosmology101.wikidot.com/redshift-and-expansion http://tangentspace.info/docs/horizon.pdf Both articles require little math to understand they have simple formulas as a reference. I also recommend This FAQ style article http://arxiv.org/abs/1304.4446 *"What we have learned from observational cosmology" ( working from phone so ignore spell and grammar mistakes currently 50 km from true North pole) Edited November 27, 2014 by Mordred 2 Link to comment Share on other sites More sharing options...
Ophiolite Posted November 27, 2014 Share Posted November 27, 2014 @Michel and Dima, Are you unable to understand this, or do you not want to understand this? I am curious. Both of you appear to be using the argument of personal incredulity. 1 Link to comment Share on other sites More sharing options...
Strange Posted November 27, 2014 Share Posted November 27, 2014 Agen stream of ether. There was no mention of, nor need for, any such aether. Imagine you and Michael are floating alone in space. You are also drifting apart slowly. The two of you are tossing a ball between you and, because there is nothing else to do, timing how long it takes. Because you are drifting apart, the ball takes a greater time to travel the distance each time you throw it. Does that require "aether" to explain it? Link to comment Share on other sites More sharing options...
Mordred Posted November 27, 2014 Share Posted November 27, 2014 To add to To the latter comments. Their is no mysterious substance such as the ether. Needed to explain the thermodynamic properties of the big bang theory nor in the popular LQC alternative. When you study thermodynamic history and observable measurements as well as combine that understanding with the SO(5) or SO(10) particle physics models. A greater sense of true understanding applies. The articles I posted is just a preliminary touching ground. The site in my link has a full manual though older roughly 5 years The info is provided the details come with how much you choose to study to truly understand Link to comment Share on other sites More sharing options...
DimaMazin Posted November 27, 2014 Author Share Posted November 27, 2014 (edited) There was no mention of, nor need for, any such aether. Imagine you and Michael are floating alone in space. You are also drifting apart slowly. The two of you are tossing a ball between you and, because there is nothing else to do, timing how long it takes. Because you are drifting apart, the ball takes a greater time to travel the distance each time you throw it. Does that require "aether" to explain it? t=(distance at instant of emission) /c What is your equation? Edited November 27, 2014 by DimaMazin Link to comment Share on other sites More sharing options...
Strange Posted November 27, 2014 Share Posted November 27, 2014 t=(distance at instant of emission) /c What is your equation? I am not talking about equations. I am simply pointing out that changing distance (and the corresponding changes in travel time) do not require an aether. But actually your equation is wrong. It fails to take into account the fact the distance is changing while the ball or light is travelling. Link to comment Share on other sites More sharing options...
DimaMazin Posted November 28, 2014 Author Share Posted November 28, 2014 I am not talking about equations. I am simply pointing out that changing distance (and the corresponding changes in travel time) do not require an aether. But actually your equation is wrong. It fails to take into account the fact the distance is changing while the ball or light is travelling. You don't make math but do you think the shame on me? Your math is: t=(distance at instant of emission)/(c+velocity of source) Link to comment Share on other sites More sharing options...
MigL Posted November 28, 2014 Share Posted November 28, 2014 Yes, to put it simply, extremely far-away galaxies will move away from us faster than c, so their light will never reach us. There is an 'outside' to what we can observe ( observable universe ) which we'll never see and can never affect us. Link to comment Share on other sites More sharing options...
Mordred Posted November 28, 2014 Share Posted November 28, 2014 (edited) You don't make math but do you think the shame on me? Your math is: t=(distance at instant of emission)/(c+velocity of source) This math is still wrong. It does not account for expansion. You evidentally didn't read my post in regards to the Hubble sphere and cosmological event horizon ( observable universe) The proper distance to a stellar object is given by [latex]Proper distance =\frac{\stackrel{.}{a}(t)}{a}[/latex] a is the scale factor. The dot above represents the scale factor today. See my earlier posted articles for clarification. Yes, to put it simply, extremely far-away galaxies will move away from us faster than c, so their light will never reach us. There is an 'outside' to what we can observe ( observable universe ) which we'll never see and can never affect us. To clarify this we can see objects with an apparent recessive velocity at z=1090 of 3c . However the object is not moving at 3c . Recessive velocity is a distance dependant measurement. Hubble's law states " the greater the distance the greater the recessive velocity." [latex]v_{recessive}=H_oD[/latex] Locally light can overcome the rate of expansion 70 km/s/Mpc. At each Mpc divident the rate of expansion is no obstacle. Recessive velocity becomes greater than c past the Hubble sphere. However that measurement is total distance between us and the Hubble sphere. It is an apparent not an actual velocity. All of this is covered in the article I posted earlier. http://tangentspace.info/docs/horizon.pdf However as the universe is flat S(k)=0. You can use the 4d distance formula of the FLRW metric conniving distance equation. (In the notation from Barbara Ryden "Introductory to Cosmology" [latex]d{s^2}=-{c^2}d{t^2}+a{t^2}[d{r^2}+{Sk}{r^2}d\Omega^2][/latex] [latex]S\kappa r= \begin{cases} Rsin ,r/R & k=+1\\ r & k=0\\ Rsinh,r/R & k=-1 \end {cases}[/latex] See the universe geometry article below its 2 pages http://cosmology101.wikidot.com/universe-geometry The link to page two is http://cosmology101.wikidot.com/geometry-flrw-metric/ This breaks down the distance measures in 2d 3d and 4d with the FLRW metric. The first page describes what is meant by flat or curved universe geometry. The second page shows the metrics in each case. Flat, positive or negative curved. The difference between commoving and proper can be found here http://en.m.wikipedia.org/wiki/Comoving_distance You will note Another varient on the commoving distance formula both are compatible Edited November 28, 2014 by Mordred 1 Link to comment Share on other sites More sharing options...
Strange Posted November 28, 2014 Share Posted November 28, 2014 Yes, to put it simply, extremely far-away galaxies will move away from us faster than c, so their light will never reach us. Actually, we can see galaxies that are receding faster than c. 1 Link to comment Share on other sites More sharing options...
MigL Posted November 28, 2014 Share Posted November 28, 2014 Yeah, maybe I put it too simply. And Mordred had already explaned the difference between the Hubble sphere and Cosmological event horizon. Link to comment Share on other sites More sharing options...
Mordred Posted November 28, 2014 Share Posted November 28, 2014 (edited) my two favourite articles covering distance measure and superluminal expansion is "Distance measures in Cosmology by David Hogg's http://arxiv.org/abs/astro-ph/?9905116 http://arxiv.org/abs/astro-ph/0310808:"Expanding Confusion: common misconceptions of cosmological horizons and the superluminal expansion of the Universe" Lineweaver and Davies Edited November 28, 2014 by Mordred 1 Link to comment Share on other sites More sharing options...
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