December 18, 2014

3:28 PM | Someone is Wrong on the Internet.
Many of the readers of this blog will probably recognise the title of this post, as the punch line to one of the best ever xkcd cartoons. Regular readers will also know that the Renaissance Mathematicus cannot resist stamping on … Continue reading →
12:44 AM | Language and Mathematics
If you write out the names of the natural numbers in English (ONE, TWO, THREE, […]

December 16, 2014

10:37 AM | Di 28 ce n'è 1
Storia, matematica, misteri e aneddoti su calendario, giorni, settimane, mesi, anni, i loro nomi, le loro origini, i loro rapporti con il moto degli astri. Tutto questo lo troverete in Di 28 ce n'è 1, ebook dei Rudi Mathematici incluso nella collana “AltraMatematica”.La lettura è scorrevole, piacevole ma soprattutto interessante. Ho scoperto una serie di fatti così dettagliati e affascinanti sulla storia dei calendari che uno si chiede: ma come hanno fatto a scoprirli […]

December 15, 2014

11:04 AM | A very similar luminous lustre appears when one observes a burning candle from a great distance through a translucent piece of horn.
On 15 December 1612 (os) Simon Marius, Court Mathematicus in Ansbach, became the first astronomer to record a telescopic observation of the Andromeda Nebula. The importance of this observation was that whereas other known nebulae such as the Orion Nebula, … Continue reading →
7:54 AM | Abbinamenti eclettici...
... quelli di alcuni dei miei lettori.Ma molti altri ne fanno di meno arditi.E quelli dei lettori tedeschi sono ancor meno creativi.

December 14, 2014

2:28 PM | Carnevale della Matematica #80: Matematica e irrazionalità
È dicembre ma prima degli elfi, folletti, gnomi, renne e befane arriva il #carnevaledellamatematica nella sua edizione #80. Ad ospitarlo è un certo Dioniso (Babbu per i più piccoli) su Pitagora e dintorni. Il tema è Matematica e irrazionalità. E chi può negare che sia un tema che ha a che fare con elfi, folletti, gnomi, renne e befane?Ovviamente è un carnevale bellissimo. E possiede addirittura una sua melodia. Forse una melodia natalizia? Chissà?  E allora che […]
2:19 PM | Halbach & Visser: Self-reference in arithmetic
New in the Review of Symbolic Logic (part 1, part 2) A Gödel sentence is often described as a sentence saying about itself that it is not provable, and a Henkin sentence as a sentence stating its own provability. We discuss what it could mean for a sentence of arithmetic to ascribe to itself a property such as provability or unprovability. The starting point will be the answer Kreisel gave to Henkin’s problem. We describe how the properties of the supposedly self-referential sentences […]

December 13, 2014

1:19 PM | Storify'd Michael Beaney's Vinna Circle Lecture on Susan Stebbing
[View the story "Michael Beaney's Vienna Circle Lecture on Susan Stebbing" on Storify]
12:51 PM | More on Shatunovsky, Kagan, and Yanovskaya
In response to my post about "lesser known Russian/Soviet logicians", Lev Beklemishev commented: Dirk van Dalen was interested in Shatunovsky's work and at his request I procured a copy of his book on the development of algebra on the basis of what can be called rudimentary constructivist ideas. This was, of course, pre-Brouwerian, and the ideas o f Shatunovsky were perhaps more in line with Kroneker's. In any case, this was interesting to see, but it never came to a publication on it with […]
8:30 AM | One of Peggy Sue's Other Numbers
Remember that sweet Italian girl I told you about a month ago.  She's back.  It seems that the coolness of the Tyrrhenian Sea and the heat of Vesuvius creates a temperature difference powerful enough to drive a person's mind into new territories.The last time we saw a fraction whose decimal expansion produced the 13 times table.  Now we have a fraction whose decimal expansion produces powers of 13. […]

December 10, 2014

9:56 AM | Frammento di Mottetto Gaussiano
Quale codice si celerà sotto queste note? Sarà Fibonacci? Sara la sezione aurea? Sarà il Codice Da Vinci? O altro e ben più occulto codice?Se non lo trovate potrete sempre scoprirlo leggendo il Carnevale della Matematica #80 tra meno di quattro giorni.melodia gaussiana

December 09, 2014

3:42 PM | Some Lesser Known (to me) Russian/Soviet Logicians
I'm working on a paper that features Moses Schönfinkel, so I was reading through a manuscript of his where he rattles off a long list of important logicians.  In addition to the usual suspects, it features the names "Schatunowski, Sleschinski, Kahan, Poretski."  I spent the better part of a day trying to figure out to whom he was referring: Samuil Osipovich Shatunovsky (1859-1929) was a mathematician working in Odessa who, so Wikipedia, "independently from Hilbert, he developed a similar […]
3:36 PM | Retelling a story – this time with all the facts
Before 1995 probably only a handful of people interested in the history of navigation had ever heard of the English clockmaker John Harrison and the role he played in the history of attempts to find a reliable method of determining … Continue reading →

December 08, 2014

2:29 PM | Graduate Programs in Philosophical Logic
Shawn Standefer has done us all a great service by starting and populating a Wiki of PhD programs in Philosophical Logic! This wiki provides an unranked list of PhD (and (eventually) terminal M.A.) programs that have strengths in philosophical logic. Links are provided to the websites, CVs, and PhilPapers profiles of the relevant faculty at each program. Additionally, when known, the specialities and willingness of faculty members to work with new graduate students are noted. The primary […]
12:33 PM | Pietre d'inciampo (Stolpersteine) o sampietrini della memoria
Ho notato che queste nuove Pietre d'inciampo sono comparse tutte assieme in diversi punti della città.

December 06, 2014

6:06 PM | One person's modus ponens...
...is another's modus tollens. [W]hen I was nine years old, I came down with scarlet fever. [...] During that year there was nothing in the world which I wanted so much as a bicycle. My father assured me that when I got well I would get one but, childlike, I interpreted this as meaning that I was not going to get well. Julia Robinson, in: Constance Reid, The Autobiography of Julia Robinson. The College Mathematics Journal, Vol. 17, No. 1, (1986), pp. 3-21
4:25 PM | Adolf Lindenbaum
Jan Zygmunt and Robert Purdy have a paper ("Adolf Lindenbaum: Notes on his Life, with Bibliography and Selected References", open access) in the latest issue of Logica Universalis detailing what little is known about the life of Adolf Lindenbaum (1904-1941). It includes a complete bibliography of Lindenbaum's own publications and public lectures, as well as a bibliography of articles in which results are credited to Lindenbaum.  Another paper on Lindenbaum's mathematical contributions is in […]

December 04, 2014

2:53 PM | The weather and the stars
My attention was recently drawn to the MacTutor history of maths website article on The History of Weather Forecasting. The article is largely concerned with the mathematics of weather forecasting from the nineteenth century onwards but has some short introductory … Continue reading →
10:09 AM | Il mio secondo ebook: La Musica dell'irrazionale
È stato pubblicato il mio secondo ebook per la collana Altramatematica. È una sorta di seconda parte del mio primo ebook. Si intitola "La Musica dell'irrazionale" ed è una storia di scoperte, trame e intrighi tra gli allievi della scuola di Pitagora.Ecco la quarta di copertina:Ippaso, un giovane atletico e brillante. Il più intelligente della scuola di Pitagora ma anche il più ribelle e arrogante. Quali saranno l’amore segreto e la scoperta che lo metteranno in […]

December 03, 2014

8:30 AM | The First Pig Latine Alphamagic Square
First Known Alpha Magic Square in Pig Latin - I Think The faculty, staff and […]

December 02, 2014

2:56 PM | Kennedy's Interpreting Gödel Out Now
Interpreting Gödel: Critical Essays, edited by Juliette Kennedy, was just published by Cambridge. It looks extremely interesting, with an all-star cast of contributors: 1. Introduction: Gödel and analytic philosophy: how did we get here? Juliette KennedyPart I. Gödel on Intuition:2. Intuitions of three kinds in Gödel's views on the continuum, John Burgess 3. Gödel on how to have your mathematics and know it too, Janet FolinaPart II. The Completeness Theorem:4. Completeness and the ends of […]
8:30 AM | Alpha Magic Squares
One of the newest development in the area of study related to magic squares is […]

December 01, 2014

8:30 AM | Solution to Friday's Brain-O Quiz
Solution to Fridays Brain-O Quiz.1.  “S”.  Look at the first let […]
8:30 AM | Calendar Update
It is the 335th day of the year, 1431st day of the decade, and 5084th day of the c […]

November 29, 2014

8:30 AM | Interesting Numbers
I have not found a special name for these two numbers, other than their description.  They are equal to the sum of their digits raised to its reversed digits power. […]

November 28, 2014

6:42 PM | Mega inanity
Since the lead up to the Turing centennial in 2012 celebrating the birth of one of the great meta-mathematicians of the twentieth century, Alan Mathison Turing, I have observed with increasing horror the escalating hagiographic accounts of Turing’s undoubted historical … Continue reading →
5:49 PM | Two New(ish) Surveys on Gödel's Incompleteness Theorems
Gödel's incompleteness theorems have many variants: semantic vs. syntactic versions, which specific theory is taken as basic, what model of computability is used, which logical system is assumed to underlie the provability relation, how syntax is arithmetized, what hypotheses the theorem itself uses (soundness, consistency, $\omega$-consistency, etc.). These result in trade-offs regarding simplicity of the proof, but also scope of application and consequences that can be drawn. There are two […]
3:52 PM | Possible Postdoc on Genesis of Mathematical Knowledge
Via the APMP list: Expressions of interest are invited for a postdoc grant (financed by Junta de Andalucia) associated with the following research project:  “THE GENESIS OF MATHEMATICAL KNOWLEDGE: COGNITION, HISTORY, PRACTICES” (P12-HUM-1216). IP: Jose Ferreiros Contact: josef@us.es The grant consists in a 2-year research contract to be held at the University of Sevilla. Salary is in the range of 84000 euros for 24 months. Holders must have obtained their PhD before start of the grant, […]
10:36 AM | Il sole e la luna
Quando ballate siete il sole e la luna ci disse un signore tempo fa dopo averci visto ballare. E allora quale idea migliore per un regalo a Zucchero?Così oggi ci siamo preparati il primo tè nelle nostre nuove tazze. (Il mio in realtà era un miscuglio di spezie indiane. Sapete, da quando sono stato a Mumbai... ;-)) Ma chi sarà il sole e chi la luna?
9:40 AM | Cinema! Italia! - Miele di Valeria Golino
Si deve essere proprio bravi per riuscire a costruire così bene una storia intorno a un tema così complicato e delicato. Ed è difficile credere che Miele sia un'opera prima. La Golino riesce ad affrontare senza sconti quel tema ma lo fa con la giusta alchimia di attese; di domande che trovano o evocano risposte al momento giusto; di relazioni - superficiali e insignificanti alcune spigolose e profonde altre - che delineano una personalità complessa e affascinante; e senza […]
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