Dark Matters

Recent dark musings now summarised on vixra.

News from Fermi

From Fermi LAT:

One example is the well-known radio galaxy NGC 1275, which is a bright, isolated source below 10 GeV. At higher energies it fades appreciably and another nearby source begins to appear. Above 100 GeV, NGC 1275 becomes undetectable by Fermi, while the new source, the radio galaxy IC 310, shines brightly.

More Quick Neutrinos

I was told that New Scientist had yet another story on the impossibility of superluminal neutrinos, but it turns out to be yet another case of imposing a classical concept of energy on a phenomenomen that quite clearly won't be adequately explained by such a theory, if true. Weak logic makes poor news. Back in OPERA month, we mentioned classical tachyons, whose low energy states move at the fastest speed, but this old rule could easily be inverted in quantum gravity, so that tachyons travelling just faster than $c$ are the black sheep.

A more interesting article from this edition is a note on dark matter in globular clusters.

Perturbative Dark Matter

The $N = 8$ discussion on the dark sector reminds us that dark matter is empirically described at galactic scales by MOND. Recall that we required duality in order to justify the existence of a stable $1/r$ law, and abstract duality does indeed underlie the $2 \times 2$ Jordan structure of the $N = 8$ theory, which may be expressed in braid diagrams.

What about galaxy cluster scales? Assumptions regarding perturbative locality must break down somewhere. For a galaxy, we correlate the so called dark force with the acceleration of outer bodies. This empirical observation alone strongly suggested a tight connection between the dark energy and the dark matter.

Quote of the Month

"Our work has shown that stars have no problem making complex organic compounds under near-vacuum conditions,” says Kwok. “Theoretically, this is impossible, but observationally we can see it happening.”

via Physics World

Dark Matter at the LHC III

Now we see what this whole AdS/CFT business is about: the two sides of the correspondence are actually exactly the same thing, appearing distinct only through the use of a wrong language and wrong physics. Quark lepton complementarity informs us about electroweak scale physics, as we extend the mirror neutrino CMB correspondence to the Koide masses of the quarks.

$\bullet$ mirror $\nu$: cosmic $T \in (1.40, 2.73, 135.9)$ K (future, present, past)
$\bullet$ u quarks: $T \in (4.8 \times 10^{9}, 3.0 \times 10^{12}, 4.1 \times 10^{14})$ K
$\bullet$ d quarks: $T \in (1.3 \times 10^{10},1.8 \times 10^{11},1.1 \times 10^{13})$ K

Observe that the $(u,d,s)$ triplet have temperatures below the QCD critical point at $4 \times 10^{11}$ K, while the $(c,b,t)$ triplet has temperatures above this point. The minimal quark temperature of $T_{u} = 5 \times 10^{9}$ K corresponds to the quark to lepton transition in the early universe. In our time, the RHIC and ALICE ion collision experiments create temperatures of trillions of degrees in the laboratory, and the other LHC experiments also observe a quark gluon plasma. In the next few years, we should learn a great deal about EW symmetry breaking.

Superluminal Astrophysics II

What the mountain of new hep-ph reports won't tell you is that apparent superluminal motion is possible within classical general relativity, such as in an application of the Kerr metric to black hole jet observations. Jets of quasars, like 3C273 and 3C345, also exhibit apparent superluminal motion, if one takes seriously the redshift as a distance indicator.

Broderick's Blazars

For today, a brief summary of Avery Broderick's excellent PI talk on TeV blazars. The hypothesis is that complex plasma instabilities, that arise in the interaction of photons, produced $e^{-}e^{+}$ pairs and the CMB background, efficiently thermalise the very high energy gamma rays. The talk discusses the consequences of this hypothesis. Observations of around $50$ nearby extragalactic TeV blazars were made with HESS, Magic and Veritas, and compared to Fermi LAT results in the $< 100$ GeV range.

For the full results see this series of papers. The blazar count peaks at the small redshift of $z = 0.1$, suggesting that TeV gamma rays from further away are absorbed, and the question is, via what process? Supposedly, the TeV photons pair produce, resulting in a so called inverse Compton cascade, where interaction with the CMB results in secondary gamma ray photons. Altogether, we have an intergalactic background plasma, which is studied numerically to obtain parameters such as an inverse Compton cooling rate. Potential consequences include the following.

1. An improved understanding of the intergalactic magnetic field. Fermi has indicated a strong IGMF, but the plasma instabilities could act to randomise the orientation of the $e^{-}e^{+}$ pairs.
2. There should be many more objects at high $z$, that are simply not visible. A successful blazar luminosity function was constructed using $30$ sources and a translation of the quasar luminosity function, suggesting that both object types belong to the same population.
3. A fit for the gamma ray background, which tends to be overproduced in most models.
4. Heating of the intergalactic medium, forcing a rewrite of the cosmic thermal history, whereby there is little heating today in comparison to the past. Details of Hot Void Ly$\alpha$ distributions were considered, producing good fits at low density for $z = 3$. Missing dwarf galaxies are suppressed by blazar heating, which kills around one third of them, in agreement with the observation that many dwarf haloes form at late times. An entropy history suggests that most cluster gas accretes later than $z = 1$, giving two core populations, one hot (late time) and one cold (early).

Vesta South Pole II

Via Universe Today, a new view of Vesta's south pole mountain.

The News Today

In the BBC news:

Astronomers have spotted gamma ray emissions coming from the Crab Pulsar at far higher energies than expected. This challenges notions of how these powerful electromagnetic rays ... are formed, researchers suggest in Science.

Superluminal Astrophysicists

While the rest of us are blogging, the true glory seekers have shut themselves in their offices to write papers. Seriously, I have seen them do exactly this. Now, courtesy of Collider Blog, the arXiv onslaught begins: an arXiv paper on the superluminal neutrinos.

More OPERA

Collider Blog has been fitting the three data points for the local $\Delta v/c$, from MINOS and OPERA. I have amended the graph with a constant pink line for crazy theory, which many string theorists appear to have endorsed.

Now what about the supernova results? Four detectors were operating during the day of the SN 1987A event. Wikipedia tells us what they observed: (1) Kamiokande $11$ $\overline{\nu}$, IMB $8$ $\overline{\nu}$, Baksan $5$ $\overline{\nu}$ over $13$ seconds, three hours before the photons, (2) Mont Blanc $5$ $\nu$ (yes, neutrinos) over $7$ seconds, six hours before the photons. The Mont Blanc events are generally not thought to be correlated with SN 1987A.

Let us now do the crazy theory thing and consider the possibility that astronomers do not understand supernovae. That is, from our Earth bound perspective we assume a simultaneity of both photon and neutrino output from the burst. The antineutrinos still travel at a speed very close to $c$, in order to arrive at roughly the same time as the photons (which has already been pointed out a gazillion times on the blogosphere), but we find that all $\nu$ and $\overline{\nu}$ are traveling at a speed greater than $c$.

Theoretical consistency then begs the question: why does the pink line drop to zero for large distances, in a vacuum, in the MeV range? Note that there are already several variables to play with here. First, assume that the MeV range is not the culprit (think MiniBooNE). Perhaps the pink line really is a local result, obtaining the maximum $\Delta v/c$, whereas the SN 1987A neutrinos are only tachyonic as they pass through (all very classical thinking) the stellar debris (someone already suggested this somewhere).

Many possibilities. Another crazy one is the following. What if the tachyonic neutrinos left the burst long after (as in years) the photons, so that $\Delta v/c$ matched the constant. Who are we to say that this is not the case in our frame.

Vesta South Pole

From DAWN via Universe Today, this beautiful image of the strange south pole basin on Vesta. Hopefully Louise will tell us more.

Fermi Shines II

Fermi also confirms the rise in the positron spectrum up to $200$ GeV. This would make stringers happy if there was good evidence for WIMPs, but alas there is not.

Fermi Shines

Fermi shows today that $31$ percent of gamma ray sources in its all sky map are of unknown origin.

Rebels Fight Back

Thanks to Oldershaw for pointing out a nice recent paper: The case for primordial black holes as dark matter, by the astronomer M. Hawkins. In particular, he mentions (equation (15)) Louise's cosmological law, which appears in a 1974* paper by Carr and Hawking.

*Carr B.J., Hawking S.W., 1974, MNRAS, 168, 399

Dawn At Vesta

As Louise Riofrio reminds us, Dawn has reached Vesta. The asteroid's varied surface features indicate an internal heat source.

Vote for South Africa

Where should the SKA be built? The shortlisted sites are Australia/NZ and South Africa, and the decision is due to be made early next year. At PhysicsWorld, you can cast your vote! Bear in mind that both sites have reasonable radio quietness and a willingness to devote infrastructure. So I figure it comes down to their relative appreciation for fundamental research. Vote for South Africa.

Cosmo Crisis II

One very nice talk at the conference, by Itzhak Bars, discusses the necessity of antigravity between bangs and crunches, using a special potential that is amenable to analytic solution. This is motivated by conformality conditions in Bars' two time physics, and their claim is that antigravity is unavoidable at singularities even in a semiclassical analysis. Possible observational consequences will be considered in future work.

Cosmo Crisis

The latest PI conference is titled Challenges for Early Universe Cosmology. The participants appear to be taking the theme seriously. Many talks have the title TBA. In the few talks I have watched, the speakers openly criticise the standard Big Bang cosmology, as if they had been doubtful about it for years. Turok invited people with interesting ideas to join in, but I advise against taking this suggestion seriously if you value your life. The smart move is to pretend you knew all about the insurmountable challenges facing the old world view, all along, with blatant disregard for historical analogy. They appear to have two token female speakers.