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Posts

April 21, 2014

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3:45 AM | Cross-validation in finance, psychology, and political science
A large chunk of machine learning (although not all of it) is concerned with predictive modeling, usually in the form of designing an algorithm that takes in some data set and returns an algorithm (or sometimes, a description of an algorithm) for making predictions based on future data. In terminology more friendly to the philosophy […]

Bailey, D., Borwein, J., de Prado, M.L. & Zhu, Q. (2014). Pseudo-Mathematics and Financial Charlatanism: The Effects of Backtest Overfitting on Out-of-Sample Performance, Notices of the American Mathematical Society, 61 (5) 458. DOI:

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April 19, 2014

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8:25 PM | Monotonicity of EM Algorithm Proof
Here the monotonicity of the EM algorithm is established. $$ f_{o}(Y_{o}|\theta)=f_{o,m}(Y_{o},Y_{m}|\theta)/f_{m|o}(Y_{m}|Y_{o},\theta)$$ $$ \log L_{o}(\theta)=\log L_{o,m}(\theta)-\log f_{m|o}(Y_{m}|Y_{o},\theta) \label{eq:loglikelihood} $$ where \( L_{o}(\theta)\) is the likelihood under the observed data and \(L_{o,m}(\theta)\) is the likelihood under the complete data. Taking the expectation of the second line with respect to the conditional distribution of […]

Ruslan R Salakhutdinov, Sam T Roweis & Zoubin Ghahramani (2012). On the Convergence of Bound Optimization Algorithms, arXiv, arXiv:

Wu C.F.J. (1983). On the Convergence Properties of the EM Algorithm, The Annals of Statistics, 11 (1) 95-103. DOI:

McLachlan G. & Peel D. DOI:

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7:48 PM | Simulate the transit of extrasolar planets
by @ulaulaman about #exoplanets #planetary_transit #kepler_mission #nasa #astronomy The search for extrasolar planets (or exoplanets) had its first success in 1991 with the discovery of some planets orbiting around the pulsar PSR1257+12(1, 2, 3), measuring the variations of the radio pulses coming from the star. The second important milestone in exoplanet research takes place in 1995, with the discovery around the star 51 Pegasi (a star like our Sun) of a Jupiter-like planet, found at a […]

Wolszczan, A. & Frail, D. (1992). A planetary system around the millisecond pulsar PSR1257 + 12, Nature, 355 (6356) 145-147. DOI:

Wolszczan, A. (1994). Confirmation of Earth-Mass Planets Orbiting the Millisecond Pulsar PSR B1257 + 12, Science, 264 (5158) 538-542. DOI:

Mayor, M. & Queloz, D. (1995). A Jupiter-mass companion to a solar-type star, Nature, 378 (6555) 355-359. DOI:

Borucki, W., Koch, D., Basri, G., Batalha, N., Brown, T., Caldwell, D., Caldwell, J., Christensen-Dalsgaard, J., Cochran, W., DeVore, E. & Dunham, E. (2010). Kepler Planet-Detection Mission: Introduction and First Results, Science, 327 (5968) 977-980. DOI:

Lissauer, J., Fabrycky, D., Ford, E., Borucki, W., Fressin, F., Marcy, G., Orosz, J., Rowe, J., Torres, G., Welsh, W. & Batalha, N. (2011). A closely packed system of low-mass, low-density planets transiting Kepler-11, Nature, 470 (7332) 53-58. DOI:

George, S. (2011). Extrasolar planets in the classroom, Physics Education, 46 (4) 403-406. DOI:

LoPresto, M. & McKay, R. (2005). An introductory physics exercise using real extrasolar planet data, Physics Education, 40 (1) 46-50. DOI:

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April 16, 2014

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5:50 PM | L'universo spiegato a mia sorella
Non voglio fare concorrenza alla splendida spiegazione di Amedeo o a quella tecnica di Corrado, ma mia sorella, leggendo il post di pancia scritto nella sera dell'annuncio di BICEP2, ha candidamente confessato di non aver capito cosa era accaduto quel giorno. E allora proviamoci, a raccontarlo. (da The Cartoon History of the Universe #1 di Larry Gonick)C'era una volta un'idea di universo, che era la Terra al centro, quindi il Sole, la Luna e gli altri pianeti e sullo sfondo le stelle fisse, […]

Hubble E. (1929). A relation between distance and radial velocity among extra-galactic nebulae, Proceedings of the National Academy of Sciences, 15 (3) 168-173. DOI:

Gamow G. (1948). The Evolution of the Universe, Nature, 162 (4122) 680-682. DOI:

Alpher R.A. & Herman R. (1948). Evolution of the Universe, Nature, 162 (4124) 774-775. DOI:

Alpher R., Bethe H. & Gamow G. (1948). The Origin of Chemical Elements, Physical Review, 73 (7) 803-804. DOI:

Peebles P.J.E., Schramm D.N., Turner E.L. & Kron R.G. (1994). The Evolution of the Universe, Scientific American, 271 (4) 52-57. DOI:

McLeish T.C.B., Bower R.G., Tanner B.K., Smithson H.E., Panti C., Lewis N. & Gasper G.E.M. (2014). History: A medieval multiverse, Nature, 507 (7491) 161-163. DOI:

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April 14, 2014

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3:45 AM | Big data, prediction, and scientism in the social sciences
Much of my undergrad was spent studying physics, and although I still think that a physics background is great for a theorists in any field, there are some downsides. For example, I used to make jokes like: “soft isn’t the opposite of hard sciences, easy is.” Thankfully, over the years I have started to slowly […]

Lazer, D., Kennedy, R., King, G. & Vespignani, A. (2014). Big data. The parable of Google Flu: traps in big data analysis., Science, 343 (6176) 1203-1205. PMID:

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April 11, 2014

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6:02 PM | La serie infinita del triangolo aureo
Un triangolo aureo è un triangolo isoscele in cui il rapporto tra uno dei lati uguali con la base è pari alla sezione aurea $\varphi$. Utilizzando un triangolo aureo di lato 1, è possibile dimostrare che \[1 + \frac{1}{\varphi^2} + \frac{1}{\varphi^4} + \cdots = \varphi\] \[\frac{1}{\varphi} + \frac{1}{\varphi^3} + \cdots = 1\] \[\frac{1}{\varphi} + \frac{1}{\varphi^2} + \frac{1}{\varphi^3} + \cdots = \varphi\] Il triangolo aureo qui sopra è lo screenshot della applet realizzata da Irina […]

Edwards S. (2014). Proof Without Words: An Infinite Series Using Golden Triangles, The College Mathematics Journal, 45 (2) 120-120. DOI:

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1:53 PM | La serie infinita del triangolo aureo
Un triangolo aureo è un triangolo isoscele in cui il rapporto tra uno dei lati uguali con la base è pari alla sezione aurea $\varphi$. Utilizzando un triangolo aureo di lato 1, è possibile dimostrare che \[1 + \frac{1}{\varphi^2} + \frac{1}{\varphi^4} + \cdots = \varphi\] \[\frac{1}{\varphi} + \frac{1}{\varphi^3} + \cdots = \1] \[\frac{1}{\varphi} + \frac{1}{\varphi^2} + \frac{1}{\varphi^3} + \cdots = \varphi\] Il triangolo aureo qui sopra è lo screenshot della applet realizzata da Irina […]

Edwards S. (2014). Proof Without Words: An Infinite Series Using Golden Triangles, The College Mathematics Journal, 45 (2) 120-120. DOI:

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April 07, 2014

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3:45 AM | Kleene’s variant of the Church-Turing thesis
In 1936, Alonzo Church, Alan Turing, and Emil Post each published independent papers on the Entscheidungsproblem and introducing the lambda calculus, Turing machines, and Post-Turing machines as mathematical models of computation. A myriad of other models followed, many of them taking seemingly unrelated approaches to the computable: algebraic, combinatorial, linguistic, logical, mechanistic, etc. Of course, […]

Dershowitz, N. & Gurevich, Y. (2008). A natural axiomatization of computability and proof of Church's Thesis, Bulletin of Symbolic Logic, 14 (3) 299-350. DOI:

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March 30, 2014

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10:14 AM | When gaming is NP-hard
by @ulaulaman about #candycrush #bejeweled #shariki #nphard #computerscience Shariki is a puzzle game developed by the russian programmer Eugene Alemzhin in 1994. The rules are simple: (...) matching three or more balls of the same color in line (vertical or horizontal). These balls then explode and a new ones appear in their place.The first Shariki's clone is Tetris Attack, a fusion between Shariki and the most famous Tetris, also this developed in Soviet Union by Alexey Pajitnov. But the […]

Toby Walsh (2014). Candy Crush is NP-hard, arXiv:

Luciano Gualà, Stefano Leucci & Emanuele Natale (2014). Bejeweled, Candy Crush and other Match-Three Games are (NP-)Hard, arXiv:

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March 26, 2014

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3:45 AM | Algorithmic Darwinism
The workshop on computational theories of evolution started off on Monday, March 17th with Leslie Valiant — one of the organizers — introducing his model of evolvability (Valiant, 2009). This original name was meant to capture what type of complexity can be achieved through evolution. Unfortunately — especially at this workshop — evolvability already had […]

Feldman, V. (2008). Evolvability from learning algorithms., Proceedings of the 40th annual ACM symposium on Theory of Computing, 619-628. DOI:

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March 17, 2014

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1:00 AM | Computational theories of evolution
If you look at your typical computer science department’s faculty list, you will notice the theorists are a minority. Sometimes they are further subdivided by being culled off into mathematics departments. As such, any institute that unites and strengthens theorists is a good development. That was my first reason for excitement two years ago when […]

Angelino, E. & Kanade, V. (2014). Attribute-efficient evolvability of linear functions., Proceedings of the 5th conference on Innovations in Theoretical Computer Science, 287-300. DOI:

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March 15, 2014

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10:02 PM | Breve storia del pi greco - parte 2
Come l'anno scorso, anche quest'anno ecco l'estrazione delle notizie pi greche per far loro posto in un articolo a parte, consono per l'aggregazione. Ovviamente il Carnevale della Matematica #71 dedicato al pi day è sempre a disposizione per la consultazione.Warped di Mike Cavna via Bamdad's Math Comics Una volta introdotto nella matematica il $\pi$, uno dei problemi a margine per la determinazione delle sue cifre fu, evidentemente, comprenderne la sua natura, ovvero che genere di numero esso […]

Laczkovich M. (1997). On Lambert's Proof of the Irrationality of π, The American Mathematical Monthly, 104 (5) 439-443. DOI:

Zhou L. & Markov L. (2010). Recurrent Proofs of the Irrationality of Certain Trigonometric Values, American Mathematical Monthly, 117 (4) 360-362. DOI:

Niven I. (1947). A simple proof that $\pi$ is irrational, Bulletin of the American Mathematical Society, 53 (6) 509-510. DOI:

Chow T.Y. (1999). What is a Closed-Form Number?, The American Mathematical Monthly, 106 (5) 440. DOI:

Bailey D.H., Plouffe S.M., Borwein P.B. & Borwein J.M. (1997). The quest for PI, The Mathematical Intelligencer, 19 (1) 50-56. DOI:

Jesus Guillera (2008). History of the formulas and algorithms for pi, La Gaceta de la RSME, 10 (2007) 159-178, arXiv:

Aragón Artacho F.J., Bailey D.H., Borwein J.M. & Borwein P.B. (2013). Walking on Real Numbers, The Mathematical Intelligencer, 35 (1) 42-60. DOI:

Bailey D.H., Borwein J.M., Calude C.S., Dinneen M.J., Dumitrescu M. & Yee A. (2012). An Empirical Approach to the Normality of π, Experimental Mathematics, 21 (4) 375-384. DOI:

Aistleitner C. (2013). Normal Numbers and the Normality Measure, Combinatorics, Probability and Computing, 22 (03) 342-345. DOI:

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5:51 PM | Breve storia del pi greco - parte 2
Come l'anno scorso, anche quest'anno ecco l'estrazione delle notizie pi greche per far loro posto in un articolo a parte, consono per l'aggregazione. Ovviamente il Carnevale della Matematica #71 dedicato al pi day è sempre a disposizione per la consultazione.Warped di Mike Cavna via Bamdad's Math Comics Una volta introdotto nella matematica il $\pi$, uno dei problemi a margine per la determinazione delle sue cifre fu, evidentemente, comprenderne la sua natura, ovvero che genere di numero esso […]

Laczkovich M. (1997). On Lambert's Proof of the Irrationality of π, The American Mathematical Monthly, 104 (5) 439-443. DOI:

Zhou L. & Markov L. (2010). Recurrent Proofs of the Irrationality of Certain Trigonometric Values, American Mathematical Monthly, 117 (4) 360-362. DOI:

Niven I. (1947). A simple proof that $\pi$ is irrational, Bulletin of the American Mathematical Society, 53 (6) 509-510. DOI:

Chow T.Y. (1999). What is a Closed-Form Number?, The American Mathematical Monthly, 106 (5) 440. DOI:

Bailey D.H., Plouffe S.M., Borwein P.B. & Borwein J.M. (1997). The quest for PI, The Mathematical Intelligencer, 19 (1) 50-56. DOI:

Jesus Guillera (2008). History of the formulas and algorithms for pi, La Gaceta de la RSME, 10 (2007) 159-178, arXiv:

Aragón Artacho F.J., Bailey D.H., Borwein J.M. & Borwein P.B. (2013). Walking on Real Numbers, The Mathematical Intelligencer, 35 (1) 42-60. DOI:

Bailey D.H., Borwein J.M., Calude C.S., Dinneen M.J., Dumitrescu M. & Yee A. (2012). An Empirical Approach to the Normality of π, Experimental Mathematics, 21 (4) 375-384. DOI:

Aistleitner C. (2013). Normal Numbers and the Normality Measure, Combinatorics, Probability and Computing, 22 (03) 342-345. DOI:

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March 14, 2014

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9:39 PM | A brief history of pi: part 2
by @ulaulaman about #piday #pi #MachinFormula #EulerIdentity Today is the pi day, so I continue the brief history of $\pi$After the introduction of $\pi$ in mathematics, one of the quest linked with the calculation of its digits is the research about its nature, or in other words what kind of number it is. Numbers classification is simple for all: we start with natural numbers (positive and negative), and so we can define rational numbers, as the numbers generated by the ratio between two […]

Laczkovich M. (1997). On Lambert's Proof of the Irrationality of π, The American Mathematical Monthly, 104 (5) 439-443. DOI:

Li Zhou (2009). Irrationality proofs à la Hermite, arXiv:

Zhou L. & Markov L. (2010). Recurrent Proofs of the Irrationality of Certain Trigonometric Values, American Mathematical Monthly, 117 (4) 360-362. DOI:

Niven I. (1947). A simple proof that $\pi$ is irrational, Bulletin of the American Mathematical Society, 53 (6) 509-510. DOI:

Chow T.Y. (1999). What is a Closed-Form Number?, The American Mathematical Monthly, 106 (5) 440. DOI:

Bailey D.H., Plouffe S.M., Borwein P.B. & Borwein J.M. (1997). The quest for PI, The Mathematical Intelligencer, 19 (1) 50-56. DOI:

Jesus Guillera (2008). History of the formulas and algorithms for pi, La Gaceta de la RSME, 10 (2007) 159-178, arXiv:

Aragón Artacho F.J., Bailey D.H., Borwein J.M. & Borwein P.B. (2013). Walking on Real Numbers, The Mathematical Intelligencer, 35 (1) 42-60. DOI:

Bailey D.H., Borwein J.M., Calude C.S., Dinneen M.J., Dumitrescu M. & Yee A. (2012). An Empirical Approach to the Normality of π, Experimental Mathematics, 21 (4) 375-384. DOI:

Aistleitner C. (2013). Normal Numbers and the Normality Measure, Combinatorics, Probability and Computing, 22 (03) 342-345. DOI:

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March 13, 2014

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3:45 AM | From heuristics to abductions in mathematical oncology
As Philip Gerlee pointed out, mathematical oncologists has contributed two main focuses to cancer research. In following Nowell (1976), they’ve stressed the importance of viewing cancer progression as an evolutionary process, and — of less clear-cut origin — recognizing the heterogeneity of tumours. Hence, it would seem appropriate that mathematical oncologists might enjoy Feyerabend’s philosophy: […]

Nowell, P. (1976). The clonal evolution of tumor cell populations, Science, 194 (4260) 23-28. DOI:

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March 10, 2014

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8:51 PM | Stephen Hawking and the (cosmological) Riemann's zeta function
Following Emilio Elizalde (read this presentation in pdf) I found a paper by Stephen Hawking in which he used the Riemann's zeta function: This paper describes a technique for regularizing quadratic path integrals on a curved background spacetime. One forms a generalized zeta function from the eigenvalues of the differential operator that appears in the action integral. The zeta function is a meromorphic function and its gradient at the origin is defined to be the determinant of the operator. […]

Hawking S.W. (1977). Zeta function regularization of path integrals in curved spacetime, Communications in Mathematical Physics, 55 (2) 133-148. DOI:

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March 09, 2014

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10:28 AM | Extracting energy from a black hole
The Penrose process is a process theorised by Roger Penrose wherein energy can be extracted from a rotating black hole. That extraction is made possible because the rotational energy of the black hole is located, not inside the event horizon of the black hole, but on the outside of it in a region of the Kerr spacetime called the ergosphere, a region in which a particle is necessarily propelled in locomotive concurrence with the rotating spacetime. All objects in the ergosphere become dragged by […]

Reva Kay Williams (2002). The Gravitomagnetic Field and Penrose Processes, arXiv:

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March 06, 2014

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4:45 AM | Misleading models in mathematical oncology
I have an awkward relationship with mathematical oncology, mostly because oncology has an awkward relationship with math. Although I was vaguely familiar that evolutionary game theory (EGT) could be used in cancer research, mostly through Axelrod et al. (2006), I never planned to work on cancer. I wasn’t eager to enter the field because I […]

Michor, F., Hughes, T., Iwasa, Y., Branford, S., Shah, N., Sawyers, C. & Nowak, M.A. (2005). Dynamics of chronic myeloid leukaemia, Nature, 435 (7046) 1267-1270. DOI:

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February 28, 2014

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3:00 AM | Cooperation, enzymes, and the origin of life
Enzymes play an essential role in life. Without them, the translation of genetic material into proteins — the building blocks of all phenotypic traits — would be impossible. That fact, however, poses a problem for anyone trying to understand how life appeared in the hot, chaotic, bustling molecular “soup” from which it sparked into existence […]

Bianconi, G., Zhao, K., Chen, I.A. & Nowak, M.A. (2013). Selection for replicases in protocells., PLoS Computational Biology, 9 (5) PMID:

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February 27, 2014

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3:32 PM | Ganz viele Tripel-Produkte
Wieviele unterschiedliche Paar-Summen kann man aus einer bestimmten Anzahl ganzer Zahlen bilden? Aus zwei Zahlen a und b kann man offensichtlich drei Paar-Summen bilden: a+a, a+b und b+b und die sind auch alle drei unterschiedlich, wenn a und b unterschiedlich waren. Bei drei Zahlen a, b, c ist es schon nicht mehr so klar: aus…

Razborov, A. (2014). A product theorem in free groups, Annals of Mathematics, 179 (2) 405-429. DOI:

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4:45 AM | Approximating spatial structure with the Ohtsuki-Nowak transform
Can we describe reality? As a general philosophical question, I could spend all day discussing it and never arrive at a reasonable answer. However, if we restrict to the sort of models used in theoretical biology, especially to the heuristic models that dominate the field, then I think it is relatively reasonable to conclude that […]

Ohtsuki, H. & Nowak, M.A. (2006). The replicator equation on graphs., Journal of Theoretical Biology, 243 (1) 86-97. PMID:

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February 20, 2014

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10:15 PM | Un buco nero nel taschino
Grazie alla gif animata qui sotto, condivisa da +Marco Cameriero (ma ora, dopo la pubblicazione automagica su G+ gli andrà una notifica matemistica?), recupero, in italiano, un post che ho pubblicato a settembre 2013 su Doc Madhattan. Sagittarius A* (Sgr A*) è una sorgente radio astronomica brillante e molto compatta al centro della Via Lattea, vicino al confine delle costellazioni del Sagittario e dello Scorpione. SGr A* è parte di una più grande figura astronomica nota come Sagittarius A. […]

Doeleman S.S., Weintroub J., Rogers A.E.E., Plambeck R., Freund R., Tilanus R.P.J., Friberg P., Ziurys L.M., Moran J.M. & Corey B. & (2008). Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre, Nature, 455 (7209) 78-80. DOI:

Hamaus N., Paumard T., Müller T., Gillessen S., Eisenhauer F., Trippe S. & Genzel R. (2009). Prospects for testing the nature of Sgr A*'s near-infrared flares on the basis of current very large telescope - and future very large telescope interferometer - observations, The Astrophysical Journal, 692 (1) 902-916. DOI:

Wang Q.D., Nowak M.A., Markoff S.B., Baganoff F.K., Nayakshin S., Yuan F., Cuadra J., Davis J., Dexter J. & Fabian A.C. & (2013). Dissecting X-ray-Emitting Gas Around the Center of Our Galaxy, Science, 341 (6149) 981-983. DOI:

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February 19, 2014

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4:11 PM | Microstoria di una violazione
Succede che nel 2010 presso il RHIC gli sperimentali riescono a violare la parità in un plasma di quark e gluoni. E succede che dopo tre anni circa presso i laboratori Jefferson siano riusciti a completare una misura riguardante proprio la violazione della parità in un urto tra elettroni e quark(6).La cosa potrebbe avere un po' il gusto del tecnico, se non fosse che la parità è una trasformazione di simmetria secondo cui le leggi della fisica risultano conservate per un ribaltamento […]

Cox R.T., McIlwraith C.G. & Kurrelmeyer B. (1928). Apparent Evidence of Polarization in a Beam of beta-Rays., Proceedings of the National Academy of Sciences of the United States of America, 14 (7) 544-549. PMID:

Lee T. & Yang C. (1956). Question of Parity Conservation in Weak Interactions, Physical Review, 104 (1) 254-258. DOI:

Wu C.S., Ambler E., Ayward R.W., Hoppes D.D. & Hudson R.P. (1957). Experimental Test of Parity Conservation in Beta Decay, Physical Review, 105 (4) 1413-1415. DOI:

Garwin R., Lederman L. & Weinrich M. (1957). Observations of the Failure of Conservation of Parity and Charge Conjugation in Meson Decays: the Magnetic Moment of the Free Muon, Physical Review, 105 (4) 1415-1417. DOI:

Roy A. (2005). Discovery of parity violation, Resonance, 10 (12) 164-175. DOI:

Wang D., Pan K., Subedi R., Deng X., Ahmed Z., Allada K., Aniol K.A., Armstrong D.S., Arrington J. & Bellini V. & (2014). Measurement of parity violation in electron–quark scattering, Nature, 506 (7486) 67-70. DOI:

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February 17, 2014

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4:30 PM | I rompicapi di Alice: Il problema dei servizi
"Inizia dall'inizio", disse il Re con gravità, "e vai fino a che non arrivi alla fine; quindi fermati"Lewis Carroll da Alice nel Paese delle MeraviglieLa teoria dei grafi inizia con la risoluzione di un problema di geometria reale. Il geniale matematico svizzero Eulero, infatti, propose in un famoso articolo(1) la soluzione di un rompicapo basato sulla città di Konigsberg e i suoi sette ponti: (via David Galvin - pdf)la cittadina prussiana è tagliata dal fiume Pregel al cui centro si trovano […]

Kullman D.E. (1979). The Utilities Problem, Mathematics Magazine, 52 (5) 299-302. DOI:

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11:30 AM | I rompicapi di Alice: Il problema dei servizi
"Inizia dall'inizio", disse il Re con gravità, "e vai fino a che non arrivi alla fine; quindi fermati"Lewis Carroll da Alice nel Paese delle MeraviglieLa teoria dei grafi inizia con la risoluzione di un problema di geometria reale. Il geniale matematico svizzero Eulero, infatti, propose in un famoso articolo(1) la soluzione di un rompicapo basato sulla città di Konigsberg e i suoi sette ponti: (via David Galvin - pdf)la cittadina prussiana è tagliata dal fiume Pregel al cui centro si trovano […]

Kullman D.E. (1979). The Utilities Problem, Mathematics Magazine, 52 (5) 299-302. DOI:

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February 15, 2014

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4:36 PM | La conservazione dell'energia del Sole
Oggi la cattura e la conservazione dell'energia del Sole viene fatta attraverso i pannelli solari, che possiamo considerare come un primo, primitivo passo verso un controllo energetico consapevole. La strada che si potrebbe seguire sembra quella, immaginata da molti scrittori di fantascienza, di un controllo diretto dell'energia delle stelle, a incominciare da quella del Sole. E uno dei primi progetti per la cattura e la conservazione della sua energia non viene da uno scrittore, ma […]

Siemens C.W. (1882). On the Conservation of Solar Energy, Nature, 25 (645) 440-444. DOI:

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4:45 AM | Evolution is a special kind of (machine) learning
Theoretical computer science has a long history of peering through the algorithmic lens at the brain, mind, and learning. In fact, I would argue that the field was born from the epistemological questions of what can our minds learn of mathematical truth through formal proofs. The perspective became more scientific with McCullock & Pitts’ (1943) […]

Valiant, L.G. (2009). Evolvability, Journal of the ACM, 56 (1) 3. DOI:

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February 08, 2014

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3:01 PM | Dmitri Mendeleev and a brief history of the chemistry
by @ulaulaman via @smoot_ #Mendeleev #chemistry #periodictable #Lavoisier The story of the chemistry starting with the first philosophers interested in the atoms, people like Epicurus, Democritus, Kanada. The first chemist, or in other words the first scientist interested in experiments about the reactions between the substances was Jabir Ibn Hayyan. Among his discoveries and inventions we must remember crystallization, calcination, sublimation and evaporation, the acid synthesis and the […]

Amr, S. & Tbakhi, A. (2007). Jabir ibn Hayyan, Annals of Saudi Medicine, 27 (1) 53. DOI:

EAGLE, C. & SLOAN, J. (1998). Marie Anne Paulze Lavoisier: The Mother of Modern Chemistry, The Chemical Educator, 3 (5) 1-18. DOI:

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4:45 AM | Misleading models: “How learning can guide evolution”
I often see examples of mathematicians, physicists, or computer scientists transitioning into other scientific disciplines and going on to great success. However, the converse is rare, and the only two examples I know is Edward Witten’s transition from an undergad in history and linguistics to a ground-breaking career in theoretical physicist, and Geoffrey Hinton‘s transition […]

Hinton, G. E. & Nowlan, S. J. (1987). How learning can guide evolution., Complex Systems, 1 (3) 495-502. Other: Link

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February 05, 2014

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4:45 AM | Phenotypic plasticity, learning, and evolution
Learning and evolution are eerily similar, yet different. This tension fuels my interest in understanding how they interact. In the context of social learning, we can think of learning and evolution as different dynamics. For individual learning, however, it is harder to find a difference. On the one hand, this has led learning experts like […]

Frank, S.A. (2011). Natural selection II: Developmental variability and evolutionary rate., Journal of evolutionary biology, 24 (11) 2310-20. PMID:

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