Good current paper on mass / luminosity and rotation curves
in [Physics]
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From: eric gisse on 11 Jul 2010 15:20 nuny(a)bid.nes wrote: > On Jul 2, 10:41 pm, Yousuf Khan <bbb...(a)spammenot.yahoo.com> wrote: >> On 7/3/2010 6:49 AM, eric gisse wrote: >> >> > Turbulence typically refers to self-interactions within a fluid. I'm >> > pointing out the specific exception now rather than having to point out >> > later and then deal with 'but you said there's no turbulence!!!!' >> > response. >> >> > Its' like people aren't listening when I say dark matter is modeled as >> > a perfect fluid. What the hell do folks think that implies? >> >> Then it's not a perfect fluid if there are self-interactions. You can >> say it's *close* enough to a perfect fluid at the galactic scale. At >> bigger scales, it is not. Second of all, you do realize that all of >> these "if...then...but if...else..." type behaviours of Dark Matter is >> exactly what Dark Fluid is supposed to address. >> >> Yousuf Khan > > Is Dark Fluid a superfluid [...] It is not a fluid in any way, shape, or form. There are no fluidic analogies either in behavior or mathematical structure.
From: Y.Porat on 11 Jul 2010 23:14 On Jul 10, 11:14 pm, dlzc <dl...(a)cox.net> wrote: > Dear Y.Porat: > > On Jul 9, 7:51 pm, "Y.Porat" <y.y.po...(a)gmail.com> wrote: > > > > > On Jul 9, 7:48 pm,dlzc<dl...(a)cox.net> wrote: > > > > Dear Y.Porat: > > > > On Jul 9, 10:23 am, "Y.Porat" <y.y.po...(a)gmail.com> wrote: > > > > > On Jun 30, 7:52 pm,dlzc<dl...(a)cox.net> wrote: > > > > > >http://arxiv.org/abs/1005.3154 > > > > > > Provides a lot of background into how Dark > > > > > Matter is arrived at (as a free parameter, > > > > > whose spatial distribution is far from > > > > > simple, depending on the M/L modelled > > > > > internal to the target galaxy). > > > > > -------------------- > > > > see My 'Circlon'' idea !!! > > > > Y.Porat > > > > --------------------- > > > > Doesn't work, even if light had mass. The mass > > > is bound to galaxies, and there is not enough > > > gravity to do that far from black holes. > > > ---------------------- > > YOU HAVE TO DECIDE ONCE AND FOR ALL > > WHETHER TH EPHOTON HAS MASS OR NOT > > OR ELSE YOU CANT MAKE REAL ADVANCE !!! > > DO NOT SHOUT. > > Your circlons still travel at c. They cannot be Dark Matter. That is > my total concern. >---------------------- did i say anything about the velocity of the Circlon ??!! i said that its motion is a double motion 1 the velocity in its circle 2 the velocity of the plan in which it moves **perpendicular to that plan** althogether a hellix !! (you see i dont shout now ... (:-) so onlynoe i suggest a velocity for it it is velocity desctibed i part 2 above iow thevelocity perpendicular toth eplan of its circula motion ie the velocity in which that ;hellix' moves is c !!! so now i just wonder if that velocity **in that above circle** (of the hellix)-- might be Pai times c ?? is it better for your findings ?? or may be no connection between velocity 1 and velocity 2 ??? 3 how does your dark matter makes any attraction?? TIA Y.Porat -------------------------- > If I were trying to reconcile my utter disdain of Dark Matter, I > certainly would not choose a model of light that is obviated by all > the other most successful physics theories we have. Hard enough to get > people to look at the band-aid that is Dark Matter, without bringing > in *your* personal kook-ese. > > I don't mind kook-ese, as long as I have enough milk. I don't. > > David A. Smith
From: dlzc on 12 Jul 2010 09:59 On Jul 10, 3:45 pm, eric gisse <jowr.pi.nos...(a)gmail.com> wrote: > dlzc wrote: > > [...] > > > > > The intergalactic and interstellar materials are known > > (by the heavier elements) to be *ionized* to that > > temperature, not "moving at that speed". > > Learning what temperature means would be abundantly > helpful here. > > [...] http://arxiv.org/abs/1005.1085 http://arxiv.org/abs/0911.2192 http://arxiv.org/abs/0712.0476 Hard to believe one could have gravitationally bound matter, that was moving in excess of escape speed. So yes, Eric, again you do need to know a bit more about temperature, and that the "kinetic theory of gases" is not the only way to do that. *If* it is so bound. I've already said they measured the temperature by the first ionization, the first absorption band, of one of the minority constituents. If you feel this is invalid... David A. Smith
From: Yousuf Khan on 12 Jul 2010 11:22 On 7/6/2010 9:43 AM, dlzc wrote: > Dear Yousuf Khan: > > On Jul 5, 2:32 am, Yousuf Khan<bbb...(a)yahoo.com> wrote: >>> 1 atom per cc in the Milky Way is known. I figure this >>> comes out to 0.3 solar masses per cubic light year. >> >> Well, the 1 atom/cc average probably includes the >> mass of stars and their orbiting stellar systems. > > No. It is inferred from various measurements, and is *just* the gas / > dust between the stars, or average, for the Milky Way. > >> So by the law of averages, in areas of vacuum, the >> average density is probably less. The 0.3 solar >> mass/cly sounds an awful lot like the density of >> the surrounding neighbourhood of the Sun: the Sun >> is the only star for 4 light years, so dividing the >> mass of the Sun around this volume would likely >> result in 0.3 solar masses per cubic light year. > > No, this is actually the interstellar density, in addition to the Sun. Okay, I know you've corrected this in a later post: > I was off by a factor of about 1000. It is more like 1/1000th of the > mass of our Sun per cubic light year, at least near the galactic > plane. So does this change your opinion somewhat? Does this mean there isn't enough regular invisible matter inside galaxies to account for the Newtonian galaxy rotation curves? Also where are you getting your figures from? >>>> then why aren't we seeing it within our own galaxy, >>>> where there should be plenty of X-ray sources >>>> lighting up the sky, at least from within the galactic >>>> disk? >> >>> We know this normal mass is here. We cannot see >>> variations in these x-ray sources along the galactic >>> plane, in much the same way we did not "know" the >>> ozone layer blocked UV from stars, until the ozone >>> hole allowed UV spectral lines to be detected. >> >> We didn't know the ozone was blocking UV >> beforehand? I find that hard to believe. The ozone >> layer scare was only in the early 80's/late 70's, so >> we learned about this connection so recently? > > Some people knew ozone absorbed UV. But it surprised scientists that > stars "developed" UV spectra on film through the ozone hole. > http://www.theozonehole.com/fact.htm > .... talks about what was known and suddenly realized. Well, I had recently posted a link about how on some planets around red dwarfs, UV may actually be producing more ozone, which blocks further UV from penetrating the planet surface. Red Dwarfs May Be Safe Havens For Life : Discovery News "But there is one big catch. Young red dwarfs have a petulant youth stretching over billions of years. Titanic stellar flares erupt without warning and blast out lethal doses of ultraviolet radiation. Ocean life on a planet may be safe from the UV just a few feet underwater and still extract enough light for photosynthesis. But anything living on the surface could get fried without a liberal coating of Sunscreen 2000. But we now have a glimmer of hope for red dwarf planets. Astrobiologist Antigona Segura of the Universidad Nacional Aut�noma de M�xico (UNAM) in Mexico City, simulated how a 1985 flare from the nearby red dwarf AD Leonis would have affected a hypothetical Earth-like planet orbiting a dwarf. Agular dwarf-large He found that UV radiation actually split molecules of oxygen to create more ozone than it destroyed. The simulation made a thicker ozone layer in the planetary atmosphere such that the surface experienced no more radiation than is typical on a sunny day on Earth." http://news.discovery.com/space/red-dwarfs-may-be-safe-havens-for-life.html#mkcpgn=rssnws1 >>> The M/L assumption assumes the "average stars" >>> in all areas of the disk: >>> - are the same size / volume, >>> - same temperature / age, >>> - are "amplified" by the same amount of attendant >>> dust (scatters light from nearby stars), and >>> - are accompanied by the same amount of >>> "unbelievably ionized" normal matter per unit area >>> (rather than volume). If it is diffuse, there needn't >>> be viscosity to speak of, just interfaces defined by >>> stellarsheaths. >> >> I'm not getting what you're trying to say about >> ionized matter (regardless of whether it is >> "unbelievably" ionized or not). What's the ionized >> matter supposed to represent? > > Emissions form stars, supernovae, and remnants of the Big Bang. So how does this ionized matter affect what you're trying to prove here? >> Also not getting what the difference is whether they >> are assuming it over a unit area or a unit volume. What >> difference would that make? > > Visible or luminous matter is confined to a thin disk, that gets > thinner with increasing r. Yet "Dark Matter" is semispherical or > torus shaped, if Andromeda is a good guide. The difference is the > average density required... So you're saying that there's more ionized matter above and below the galactic disk? Yousuf Khan
From: Steve Willner on 12 Jul 2010 13:41
In article <09924fc4-4e68-4f41-ad96-b3faa7002ed9(a)y12g2000prb.googlegroups.com>, dlzc <dlzc1(a)cox.net> writes: > The intergalactic and interstellar materials are known (by the heavier > elements) to be *ionized* to that temperature, not "moving at that > speed". The kinetic temperature of a plasma indicates the speeds of motion of the ions and electrons. At high temperatues and even at modest ones of a few thousand K, the Maxwell distribution is an excellent approximation for the speeds. The ionization state of a plasma may or may not reflect its kinetic temperature. In H II regions, for example, the hydrogen is nearly fully ionized by UV radiation from nearby stars, but the kinetic temperature is only of order 10^4 K. The buzz phrase to look for is "local thermodynamic equilibrium" or LTE. -- Help keep our newsgroup healthy; please don't feed the trolls. Steve Willner Phone 617-495-7123 swillner(a)cfa.harvard.edu Cambridge, MA 02138 USA |