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From: Simple Simon on 17 Mar 2010 09:31 eric gisse wrote: > Simple Simon wrote: > >> Is it possible that some of the dark matter is simply matter that is >> outside of our past light cone but gravitationally bound to objects >> within it? > > No. /!y?/
From: Simple Simon on 17 Mar 2010 09:31 Tom Roberts wrote: > Simple Simon wrote: >> Is it possible that some of the dark matter is simply matter that is >> outside of our past light cone but gravitationally bound to objects >> within it? > > No. It is not possible for such matter to REMAIN outside our past > lightcone. > > > Tom Roberts I don't understand. You seem to be saying that it is not possible for the path of objects (an hence their position relative to other objects to which they are gravitationally bound (e.g. within the same galaxy) within our current past-lightcone to have been effected by matter outside it because any such matter would necessarily be within some future past-lightcone of ours. Is that correct?
From: Androcles on 17 Mar 2010 08:43 "Simple Simon" <pi.r.cubed-nospam(a)gmail.com> wrote in message news:cY3on.88403$K81.65523(a)newsfe18.iad... > Tom Roberts wrote: >> Simple Simon wrote: >>> Is it possible that some of the dark matter is simply matter that is >>> outside of our past light cone but gravitationally bound to objects >>> within it? >> >> No. It is not possible for such matter to REMAIN outside our past >> lightcone. >> >> >> Tom Roberts > > I don't understand. You seem to be saying that it is not possible for the > path of objects (an hence their position relative to other objects to > which > they are gravitationally bound (e.g. within the same galaxy) within our > current past-lightcone to have been effected by matter outside it because > any such matter would necessarily be within some future past-lightcone of > ours. > Is that correct? > Dork matter can do whatever the dorks say it can do.
From: Simple Simon on 17 Mar 2010 10:10 Simple Simon wrote: > Tom Roberts wrote: >> Simple Simon wrote: >>> Is it possible that some of the dark matter is simply matter that is >>> outside of our past light cone but gravitationally bound to objects >>> within it? >> >> No. It is not possible for such matter to REMAIN outside our past >> lightcone. >> >> >> Tom Roberts > > I don't understand. You seem to be saying that it is not possible for > the path of objects (an hence their position relative to other > objects to which they are gravitationally bound (e.g. within the same > galaxy) within our current past-lightcone to have been effected by > matter outside it because any such matter would necessarily be within > some future past-lightcone of ours. > Is that correct? Corrected typos: I don't understand. You seem to be saying that it is not possible for the path of objects (and hence their positions relative to other objects to which they are gravitationally bound (e.g. within the same galaxy)) within our current past-lightcone to have been effected by matter outside it because any such matter would necessarily be within some future past-lightcone of ours. Is that correct?
From: dlzc on 17 Mar 2010 09:58
Dear Simple Simon: On Mar 17, 7:10 am, "Simple Simon" <pi.r.cubed-nos...(a)gmail.com> wrote: > Simple Simon wrote: > > Tom Roberts wrote: > >> Simple Simon wrote: > >>> Is it possible that some of the dark matter > >>> is simply matter that is outside of our > >>> past light cone but gravitationally bound > >>> to objects within it? > > >> No. It is not possible for such matter to > >> REMAIN outside our past lightcone. > > I don't understand. You seem to be saying > that it is not possible for the path of > objects (and hence their positions relative > to other objects to which they are > gravitationally bound (e.g. within the same > galaxy)) within our current past-lightcone > to have been effected by matter outside it > because any such matter would necessarily > be within some future past-lightcone of > ours. > Is that correct? It does not even have to wait for a future light cone. If we are looking at a collection of matter + Dark Matter 1 Gly away, and we can see to 13+ Gly, how can the collection of matter + Dark Matter have had the Dark Matter disappear at this "time slice" of observation? David A. Smith |