posted by @ulaulaman about #Higgs #higgsboson #ATLAS
I try to explain because I think that tomorrow it will not be the announce of the Higgs boson discover. First of all the official statements of Sergio Bertolucci, CERN Director for Research and Computing (CERN press release):
We now have more than double the data we had last year that should be enough to see whether the trends we were seeing in the 2011 data are still there, or whether they've gone away. It's a very exciting time.
A combined search for the Standard Model Higgs boson with the ATLAS detector at the LHC is presented. The datasets used correspond to integrated luminosities from 4.6 $fb^-1$ to 4.9 $fb^-1$ of proton-proton collisions collected at sqrt(s) = 7 TeV in 2011. The Higgs boson mass ranges of 111.4 GeV to 116.6 GeV, 119.4 GeV to 122.1 GeV, and 129.2 GeV to 541 GeV are excluded at the 95% confidence level, while the range 120 GeV to 560 GeV is expected to be excluded in the absence of a signal. An excess of events is observed at Higgs boson mass hypotheses around 126 GeV with a local significance of 2.9 standard deviations (sigma). The global probability for the background to produce an excess at least as significant anywhere in the entire explored Higgs boson mass range of 110-600 GeV is estimated to be ~15%, corresponding to a significance of approximately one sigma.
I must rember you that, to declare a discover of a new particle, the result must be released with 5 sigma, and ATLAS data is given with 2.9 sigma(1).
We are really near to the Higgs boson, but we don't have the certainty, so I think that tomorrow nobody say We have discovered the Higgs boson (but I could be wrong).
posted by @ulaulaman about #higgs #physics #tevatron
This is the week of the Higgs. Indeed, wednesday, at CERN, ATLAS and CMS announced the results of the elaboration of the data collected in the first part of 2012... and a lot of journalists write about the probable discover of the Higgs boson. Indeed the two collaborations are disegned in order to discover the boson related to the mechanism that provides the mass to the other particles. Waiting for the conference, today CDF and DZero, the two collaborations of Tevatron, publicize in two conferences the first elaboration of the complete set of data about Higgs research. Their result was summarize by the following plot:
In the image there is the combination of the final results from the two collaborations. The two experiments combined detecte an excess in signals around 125 GeV with a 2.5 sigma. It is not the discover of the Higgs boson, but it could be a good clue for the existence of the boson. So I don't know if ATLAS and CMS will confirm or update this result in their next conferences, but in every case I must remmber to the readers that with a mass of 125 GeV we have need of physics beyond Standard Model, because the only SM is not sufficient to explain our universe. In order to explain better, I reprint here some considerations that I just published for the previous Higgs day:
It seems interesting for all mathematics teachers (via Tiny Teaching)
Rethinking Mathematics (RM) is ready for its second edition and needs contributors! We are excited to put forward this call and are calling on authors to submit manuscripts for consideration to Rethinking Schools as soon as possible. Our deadline for submissions for next edition of the book is September 1.
We are looking for submissions in four principal areas:
manuscripts describing teaching and learning mathematics for social justice (e.g., see RM chapters 1, 5, 9, or 12);
manuscripts describing salient issues in T/L mathematics for social justice (e.g., RM chapters 2, 3, 4, 7, or 14);
one- to three- page "mini-lessons" or "activity boxes" that teachers can use and adapt to their contexts (see RM pp. 16-18; p. 23; 29-30; or 64-67);
resources for teaching math for social justice (see RM, "Resources" section and RM itself) including cartoons, graphics, graphs, pictures, and other creative and lively ideas.
Of these, the first is our priority. And for these, we are especially looking for chapters written by (or with) classroom teachers who have actually taught the social justice lessons, and those manuscripts that emphasize student voice, real classrooms, and all the challenges of doing this work (including how teachers themselves learn and grow in the process). If you are not familiar with the Rethinking Schools magazine, please read the chapters in RM and articles in the magazine to get a sense of what Rethinking Schools publishes, and see the Rethinking Schools contributor guidelines. Several areas that we want to emphasize are articles for younger grades (K-5), international perspectives (and authors from the Global South), issues of mathematics and bi/multilingual contexts, contributions focusing on culture and cultural relevance, and submissions by authors of color.
Our view is that Rethinking Mathematics is really an ongoing project for Rethinking Schools and the wider teaching and learning mathematics for social justice "community". That is, we will always be open to considering articles for the magazine and for future editions of the book in case we are not able to accept your submission for this edition. Of course, Rethinking Schools can never guarantee publication, but the Rethinking Schools editors are committed to working with potential authors in shaping your submissions for the book or magazine.
posted by @ulaulaman #photography #computer #science #technology
Sometimes, using the Android application Wondershare Panorama, I try to shot some panoramical photos. The result is good, but it could be better, like everything: indeed the actual camera (also in our smartphones) work near the fundamental limit of 1–10 megapixels for millimetre-scale apertures(1). In theory(2) we are able to upgrade this limit. If we define $SW$ like the upper limit for the number of data channels which can be handled in parallel(2), after some calculations, Adolf W. Lohmann found that without aberration, it would increase quadratically with the scaling factor $M$(2). This result is different from the purely geometry result that states $SW$ indipendent from scaling.
That result cannot be realistic, otherwise, very long focal length lens systems would be fairly useless. In practice, the apertures of these long systems are reduced, more or less according to the empirical rule(2)
Now a team of researchers develop a new photographical device that can resolve at 50 gigapixels: AWARE-2 camera(1, *).
And below there are some examples of its capabilities(1):
posted by @ulaulaman #AlanTuring #mathematics #biology #genetics #ecology
One hundred years ago was born Alan Turing. He was known essentially for his role during the Second World War: he encrypted the Enigma machine. But He is also a brillant mathematichian and today I would try to describe one of his better model, that today biologists are applying to their research field.
A vibrating object tends to vibrate at certain preferred frequencies, called natural frequencies. These frequencies depend on properties such as the density and tension of the vibrating object. Mathematicians and physicists can determine the natural frequencies of an object when they know the values for these other properties. This article describes new work being done to solve the reverse problem - calculation of properties such as density when the natural frequencies of the object are known.
As I was scraping a brass plate with a sharp iron chisel in order to remove some spots from it and was running the chisel rather rapidly over it, I once or twice, during many strokes, heard the plate emit a rather strong and clear whistling sound: on looking at the plate more carefully, I noticed a long row of fine streaks parallel and equidistant from one another. Scraping with the chisel over and over again, I noticed that it was only when the plate emitted this hissing noise that any marks were left upon it; when the scraping was not accompanied by this sibilant note there was not the least trace of such marks.(1)
Some years after Galilei (1680), Robert Hooke
was able to see the nodal patterns associated with the modes of vibration of glass plates.
In 1787 Ernst Chladni repeated Hooke's experiments and published his results in Entdeckungen über die Theorie des Klanges (Discoveries in the Theory of Sound). Finally in 1967 Hans Jenny published Kymatik (Cymatics), a book based on Chladni's work, and cymatics became an interesting science, in particular for artists! For example, Jeff Volk, poet, writes an interesting article about Jenny and the pattern of sound: From Vibration to Manifestation (pdf). In particular he presents an image from Alexander Lauterwasser's Water Sound Images
Pay attention: following Lauterwasser and Volk we could explain the pattern of leopard's coat, but the first explanation come from one of the Alan Turing's paper The Chemical Basis of Morphogenesis(2). In this paper Turing is interested in the formation and development of path in biology (the so called phenomenon of morphogenesis).
Any pattern or shape observed in nature, even though governed by genetics, is most likely produced by an unknown mechanism. Thus, determining these mechanisms that generate pattern and shape in organisms is an important goal of theoretical biologists.(3)
The most used model for this type of systems is the reaction-diffusion system, described by the following formula:
\[u_t = d \Delta u + f (\gamma, u)\]
where $u$is the position of the gene, $u_t$ the diffusion speed, $d$, $\gamma$ real constants. We can write two similar formulas for every morphogene in the system.
Reaction-diffusion models are particularly compelling with regard to their ability to capture complex evolving patterns.(3)
Similar equations are really complex to analyze, due to their local and general phenomena. In an intuitively way, we can see the pattern formation like a challenge between reaction mode and diffusion mode. In his paper, Turing
suggested that a system of reacting and diffusing chemicals (morphogens) can interact to produce stable patterns in concentration (Turing patterns).(3)
Or in a more simple way: we can imagine the presence of an activator molecule of the morphogenesis. This molecule will be produced more and more thanks an autocatalysis process, but the activator will produce also an inhibitor, that will limit the production of the activator. The dynamics between activator and inhibitor will generate the pattern observed in nature (for example tigers' stripes). Tipically the two diffusion velocities are different, so we can explain the great variety of patterns.
