What is astronomers' dust. It begins with Newton's concept of a fine dust dust that permeated all space. It arose as a consequence of an absurdity as understood by Newton. How could the gravitational force, action at a distance, be transmitted through the empty vacuum of space? He surmised it couldn't and proposed an "atomic" solution. Space itself was filled with an extremely fine dust that filled all space between planets and stars that did not impede the flow of matter through it. There was no inertial impedance to the flow of matter particles.
Matter these days is baryonic stuff made up ultimately of the first generation or flavour of fractionally charged quarks, with charge exactly balanced by electrons to build the basic building blocks of matter we call elements or atoms.
Astronomers' dust is a generic term. Were one to take a variety of meteorites, grind them up and sort them into individual piles of grains of various mesh sizes we might expect the following abbreviated list.
Silicate grains, aluminosilicates, iron spicules and iron oxides, predominantly reduced ferrous and low ferric oxides, carbonates, elemental carbon, graphite, abiogenic organic carbon polymers, poly aromatics (PAH's), water ices with ammonia. The carbon moities are endless, literally thousands of species from methanol and hydrocarbons to amino acids to even porphyrins and panspermian bacteria and virii , while we await RNA or DNA. It's huge list and every member is made up of baryobnic fermions.
All astronomers' dust and its temperature in the interstellar environment is based upon spectrometric analysis from photons which are bosons that are the carrier force in interactions between these atoms or molecules. Infrared analysis aims to identify the species responsible for rotational and vibrational spectra within galaxies as gas clouds or interstellar dust components with broad poorly resolved spectra. Astronomers' dust is neither homogenous nor isotropic. We observe it countless times as dustlanes. In the vicinity of starforming regions we expect it to be hot, and in old star regions, cold. The heat is transported by bosons, the photon of the standard model. As a carrier of the interaction or force we can not contemplate a universe made up solely of photons at any temperature. At ultra high energies Weinberg considered the baryonic matter content of the early universe as a contaminant or trace, then only 4 baryons per cubic metre, whereas the photon numerosity was ca. 1 billion fold greater; a huge numerical ratio which he could never satisfactorily explain; baryonic dust was insufficient to thermalise radiation and account for this ridiculous ratio.
Galametz et al (MNRAS 2012) Mapping the cold dust temperatures and masses of nearby Kingfish
galaxies with Herschel http://arxiv.org/pdf/1207.1301v2.pdf
note a worrying implication on page 14 I would characterise as a major problem for baryonic dust
On the contrary, the
grand-design spiral NGC 628 or bulge-less objects like NGC 3621
or NGC 7793 show cold dust temperatures that are homogenous
throughout the structure of the galaxies. The fact that the cold
dust temperature distribution does not seem to correlate with any
dust heating source (neither star forming regions, nor old stellar
populations or radius) within the galaxies is worrying and ques-
tions the use of a free beta factor in the model, at least for this type of galaxy
Although not cited in this paper Hwang et al "Evolution of Dust Temperature of Galaxies through
Cosmic Time as seen by Herschel" 2010 http://arxiv.org/pdf/1009.1058v1.pdf
faced the same quandary, their figures 2-4 page 4 onwards.
Out to z=1 and for comparison galactic abundances tail off rapidly past z=2 for the four ultradeep surveys , the detailed sample coverage includes interacting ones and AGN's the astronomers' dust appears homogenous with dust temperatures within the limit 20-40 Kelvin with outliers in the AGN Goods survey to 50 Kelvin, whereas IR luminosities cover a three orders of magnitude variation. I would hazard a guess that dust types haven't changed in 6 billion years but that the absolute magnitude of dust mass has been increasing ie. astronomers' metallicities have increased. Yet there must be astronomers' dust because we observe the dustlanes that are not homogenous and not isotropic and yes there is a great range of dust temperatures in our immediate locale. Yet such dust is not a far more fundemental neutrino dust that operates much like Newton's concept of extremely fine dust. It could conceivably represent baryonic atomic matter I mentioned three years ago in the DM thread. Such dark atoms up 27 fold greater size than atoms carried only 1/3 charge of the atoms we know of and would have provided rotational excitations in the IR at 30 fold longer wavelengths. Such dm candidates were abandoned in favour of neutrino dust with low rest masses.
What then is Neutrino dust? First of all the neutrino is a fundamental fermion, one could argue it is more fundamental than the charged lepton or quarks in that it lacks a charge, simpler stuff by one quantum number. Flip Tonedo posted this brilliant post over on quantum diaries-http://www.quantumdiaries.org/2011/06/19/helicity-chirality-mass-and-the-higgs/
"Helicity, Chirality, Mass, and the Higgs". It is worth reading several times because it took Flip many attempts at editing to finally get it right, with a lot of help from the readership.
Remember particles are created in pairs, particles and antiparticles and are equiabundant with photons at their pair production temperatures. The only sm fermion with rest mass with an unrecognised pair production temperature are neutrinos. The antimatter particle to matter particle begin with eg. Flip's electron and positron. Forget the Higgs which is relish to the story which is not a fermion yet again has conceptually a pair production temperature associated with its production in a hot enough bath of photons. From conservation laws we expect one photon with sufficient energy per particle or two fold for the particle pair; a simple small number and not a 109
Chemists have known about helicity and chirality for six generations. For the particle physicist little more than a generation of erudition has passed. In the mid 1960's biochemists and chemists had always attempted to separate gooey mixes of optically active molecules into pure fractions and gooey fractions by definition aren't pure. Enzymes would be employed to selectively remove say right handed species, the result was the enzymes would self digest themselves and results were usually notoriously bad, full of lysed enzymes. With the advance of high resolution gas liquid chromatography on chiral liquid phases, chiral because we had formed them by total synthesis from optically pure amino acids, we were able to separate such LH and RH forms. Some gluey goooes thought to be pure from good melting point and derivative tests, contained three or four chemically different forms, notably triterpenoids. Much simpler were the protein amino acids. Leucine has two forms. Isoleucine had two known forms until two new forms were observed to be present in equilibrium mixes, denoted alloisoleucine as a left handed and a right handed form. By convention these other forms were called allo, meaning other without any preconceived idea what " other" meant than a chemically different form. There were four forms and not two. Of course, we knew structurally exactly what they were. The term mirror would imply it was a mirror reflection, which it was because we knew beforehand what the structure actually was.
The particle physicist hasn't got or lived with that luxury yet- which is why I stick to chemical nomenclature or alloneutrinos. When I say neutrino I really mean the more long winded neutrino and antineutrino pair. When I write alloneutrino it refers to the ensemble that the physicist has yet to recognise. There are twice as many neutrinos that are yet known in the physics philosophy, Marni's mirror set, yet to a chemist it's necessary and old relish! Of course the chiral sm consorts with only one of thes forms; the rest one may correctly associate with dark matter, but two of these unrecognised forms are alloneutrinos. Why should I be so arrogant about it. Because if I am wrong the cmb temperature would be 5.45 Kelvin and not precisely to great accuracy 2.725Kelvin. Why is the cmb radiation at that temperature? The simple answer is a hidden assumption. It happens to be a precise temperature on a cooling curve that so happens to be what it is because our era is the here and now after 13.7 billion years of evolution. It has to have a temperature along the cooling curve but how hot was it initially; the Planck temperature perhaps just prior to one correct inflation model. Or was there a temperature limit at 1016
Kelvin. Also if it went out of equilibrium so early and is relic radiation why did it retain its thermodynamic profile for so long? The Big Bang retains many ad hoc assumptions even with inflation. Had measurements reported 5, 10 , 15 Kelvin the self same story would have become ingrained.
Neutrinos now have rest mass , an ultra low rest mass, a cumulative mass of ~0.06eV from three flavours and the implications are truly enormous to cosmology, so much so that like the Phlogiston theory that was a physicist's theory can be safely binned with BB theory and the origin of the cmb radiation. The cmb radiation is not relic radiation at all; it is the result of photon neutrino pair production; it is what space is, what the vacuum represents- a fine mist of granular, a neutino fine dust moiety of Compton grains 1.06mm diameter , more spherical cows:). Of course chemist's love allo forms of moities that are not spherical cows and neither I expect are alloneutrinos simply preonic cows either. Unlike atoms we don't see them yet.
Marni again has reported on the dilemma yesterday. http://arcadianomegafunctor.blogspot.co.nz/
In all modesty we don't care to cite our joint vixra paper from 2010, nobody else does bar a few. Nevertheless, we did predict the creation annihilation temperatures for the suite or neutrino ensemble of three flavours, 2.725 Kelvin for the cosmic cmb and at higher densities, where the second flavour ensembles are created, at homogenous and isotropic ~21 Kelvin. So why is the spread to 50 Kelvin or 0.021eV equivalent? One may bitch about the eigenflavour values that contribute to the discrete eigenstatemasses but there is now little controversy re- the bound at 0.060eV for cumulative neutrino masses of the three flavours, 1/3 of that measure.
"Graham keeps telling us that MINOS had their chance and blew it. Probably he is right, but a poor theorist has to put some trust in the data".
Of course as scientists we have to trust data, that's the whole point of the method and there's no point reciting it any more. The Astronomical Implications thread might now as well be a dead parrot.
I spent some time, several days with a squad of British army officers, in Andalusia, on my recent visit there. I befriended a dwarf green parrot that cared to dwell on the window eaves adjacent to the cottage. It made a horrendous racket when I first approached but by day four, and after many tiny morsels of food Alexander became tame. All the time I whispered to it "What's your name" and " You are mortal". I had to leave before it risked my shoulder as a perch. Rather than being right too often they all agreed I was politely, they are all politically correct these days, eccentric rather than absolutely bonkers. One shouldn't bet on the likelihood of an inside straight, but when one is dealt it, there's no option but to bet the farm. The best thing Minos can do is fill in the mineshaft from the inside
. I grew to love that little parrot. I know nothing about parrot gender of course but I hope it survives and finds a mate. It had a mate since all parrots come in pairs too. It's mate simply went missing just before I arrived. That's life, riding high in April shot down in May.
A man went to an auction. He saw an exotic green dwarf parrot pair. The prat wanted a male bird, nobody wanted both birds, so he bid. He kept bidding, but was always outbid. He refused to stop. He finally won. The bird was his! He paid for the parrot and said to the auctioneer,
"I hope he talks. I'd hate to pay all this for a dumb parrot"
"Of course his mate can talk," said the auctioneer. "Who do you think bid against you?"