Field of Science


Systematics of Putative Euparkeriids from the Triassic of China2 hours ago in Chinleana



Black Yeasts, Black Lichens and Rotting Wood: the Chaetothyriomycetidae1 day ago in Catalogue of Organisms



Religious and paranormal believers are high in empathy – but confused about how the world works1 week ago in Epiphenom


Women in Science: an Example of Roadblocks1 week ago in Angry by Choice






Blogging Microbes Communicating Microbiology to Netizens1 month ago in Memoirs of a Defective Brain

ReBlog: June Was 6th Warmest Globally4 months ago in The View from a Microbiologist

Geology and Generals: How Geology influenced the Gettysburg Campaign (Part I.)4 months ago in History of Geology


Rule of 6ix has moved7 months ago in Rule of 6ix



Live coverage of Big Protist Conference (ICOP) in Vancouver, 28 Jul  02 Aug1 year ago in Skeptic Wonder



The Lure of the Obscure? Guest Post by Frank Stahl2 years ago in Sex, Genes & Evolution

Finding a new translation factor, and verifying it with help from my experimental friends2 years ago in Protein Evolution and Other Musings



The Large Picture Blog Has Moved3 years ago in The Large Picture Blog

Lab Rat Moving House3 years ago in Life of a Lab Rat

Goodbye FoS, thanks for all the laughs3 years ago in Disease Prone

Branson getting into microbial diversity in the deep sea3 years ago in The Greenhouse
The globe of Galileo
video by @ulaulaman #levitation
It's just a little Earth, turns and levitates above its base, reminding those who contributed to give it its rightful place in space. The globe can light up using the switch on the base. It works in the current network.Published by Gianluigi (@ulaulaman) in data:
Fabiola Gianotti, Director General at CERN
http://t.co/rYzcXWlvR0 about #FabiolaGianotti #CERN #ATLAS
Fabiola Gianotti is an Italian particle physicist, a former spokesperson of the ATLAS experiment at the Large Hadron Collider (LHC) at CERN in Switzerland, considered one of the world's biggest scientific experiments. She has been selected as the next DirectorGeneral of CERN, starting on 1 January 2016.She is the 4th italian particle physicist to became Director General at CERN after Amaldi (19521954), Rubbia (19891993) and Maiani (19992003).
A bit concession to the SEO!
Planck results, ATLAS and the dark matter
http://t.co/jJxD8rhCr6 by @ulaulaman about #Planck, #ATLAS, #DarkMatter at #LHC
The last issue of Astronomy & Astrophysics (that it's free) is devoted to the Planck 2013 results:
This collection of 31 articles presents the initial scientific results extracted from this first Planck dataset, which measures the cosmic microwave background (CMB) with the highest accuracy to date. It provides major new advances in different domains of cosmology and astrophysics.In the first paper there is an overview of 2013 science results, and we can read:
The Universe observed by Planck is wellfit by a six parameter, vacuumdominated, cold dark matter (ACDM) model, and we provide strong constraints on deviations from this model.But, in the meanwhile, ATLAS published a preprint about the quest of the dark matter in LHC:
The data are found to be consistent with the Standard Model expectations and limits are set on the mass scale of effective field theories that describe scalar and tensor interactions between dark matter and Standard Model particles. Limits on the darkmatternucleon crosssection for spinindependent and spindependent interactions are also provided. These limits are particularly strong for lowmass dark matter. Using a simplified model, constraints are set on the mass of dark matter and of a coloured mediator suitable to explain a possible signal of annihilating dark matter.Tommaso Dorigo, examining ATLAS' results, concludes:
the ATLAS search increases significantly the sensitivity with respect to past searches, but no signal is found. As attractive as DM existence is as an economical explanation of a wealth of cosmological observations, the nature of dark matter continues to remain unknown.
via phys.org
Regge theory
http://t.co/alaasqcHwl @ulaulaman says #goodbye to #TullioRegge
In quantum physics, Regge theory is the study of the analytic properties of scattering as a function of angular momentum, where the angular momentum is not restricted to be an integer but is allowed to take any complex value. The nonrelativistic theory was developed by Tullio Regge in 1957.Following Chew and Frautschi (pdf), the key papers by Tullio Regge are:
Regge T. (1959). Introduction to complex orbital momenta, Il Nuovo Cimento, 14 (5) 951976. DOI: http://dx.doi.org/10.1007/bf02728177 (pdf)
In this paper the orbital momentumj, until now considered as an integer discrete parameter in the radial SchrÃ¶dinger wave equations, is allowed to take complex values. The purpose of such an enlargement is not purely academic but opens new possibilities in discussing the connection between potentials and scattering amplitudes. In particular it is shown that under reasonable assumptions, fulfilled by most field theoretical potentials, the scattering amplitude at some fixed energy determines the potential uniquely, when it exists. Moreover for special classes of potentials $V(x)$, which are analytically continuable into a function $V(z)$, $z=x+iy$, regular and suitable bounded in $x > 0$, the scattering amplitude has the remarcable property of being continuable for arbitrary negative and large cosine of the scattering angle and therefore for arbitrary large real and positive transmitted momentum. The range of validity of the dispersion relations is therefore much enlarged.
Regge T. (1960). Bound states, shadow states and mandelstam representation, Il Nuovo Cimento, 18 (5) 947956. DOI: http://dx.doi.org/10.1007/bf02733035
In a previous paper a technique involving complex angular momenta was used in order to prove the Mandelstam representation for potential scattering. One of the results was that the number of subtractions in the transmitted momentum depends critically on the location of the poles (shadow states) of the scattering matrix as a function of the complex orbital momentum. In this paper the study of the position of the shadow states is carried out in much greater detail. We give also related inequalities concerning bound states and resonances. The physical interpretation of the shadow states is then discussed.The importance of the model is summarized by the following:
As a fundamental theory of strong interactions at high energies, Regge theory enjoyed a period of interest in the 1960s, but it was largely succeeded by quantum chromodynamics. As a phenomenological theory, it is still an indispensable tool for understanding nearbeam line scattering and scattering at very large energies. Modern research focuses both on the connection to perturbation theory and to string theory.During the 1980s, Regge is interested also in the mathematical art, using Anschauliche Geometrie by David Hilbert and Stefan CohnVossen like inspiration for a lot of mathematical objects. Good bye, Mr. Regge, and thanks for all...
Alan Guth, eternal inflation and the multiverse
http://t.co/CnvvOY0mAI about #AlanGuth #multiverse #CosmicInflation #icep2014
At the beggining of October, Alan Guth was at the workshop FineTuning, Anthropics and the String Landscape at Madrid, and he concluded his talk with the following slide:
The complete talk, without question time, follows:
Just a bit of blue
http://t.co/hgbABOxUlm by @ulaulaman about #nobelprize2014 on #physics #led #light #semiconductors
Created with SketchBookX
Now, in band theory, the probability that an electron occupies a given band is calculated using the FermiDirac distribution: this means that there is a nonzero probability that an insulator's electron in the valence band is promoted to the conduction band, but it is extremely low because of the large energy difference between the two levels. Moreover, there is an energy level said Fermi level that, while in the conductors is located within the conduction band, in the insulation is located between the two bands, the conduction and valence, allowing a valence electron to jump more easily in the conduction band.
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