Henri Poincaré, Why space with three dimensions – Analysis Situs (Topology)
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Geometers usually distinguish two kinds of geometries, which they call the first of metric and the second of projective; metric geometry is based on the notion of distance; two figures are regarded as equivalent when they are “equal” in the … Read More

XII. THE FLIGHT – DOUBLE-SPINE
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Sacred love of freedom, inspire me! … Fleeing had become a real nightmare at night, an obsession during the day. Escape … but how? I was turning in my crystal prison looking for a way out, when I knew better … Read More

Digital Assembly 2019 – Bucharest, Romania, June 13-14
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The Digital Assembly 2019 is a forum for stakeholders to take stock of the achievements of the Digital Single Market Strategy, draw lessons and to exchange views on the contours of a future digital policy. The event is also a … Read More

Henri Poincaré, Space and time (2) – Physical and psychological relativity
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The psychological time, the Bergsonian duration, from which the scientist’s time has come out, serves to classify the phenomena that occur in the same consciousness; it is powerless to classify two psychological phenomena which have for their theater two different … Read More

The adventures of a red ant: XI. IN THE BOWL – THE VARIOUS ECITONS
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The next morning, at the first light of the sun, a step was heard on the stairs, a head slowly advanced into the office. Urbain was there … His eyes went straight to his desk. “My poor ant from France!“ … Read More

Henri Poincaré, Space and time (1)
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One of the reasons that led me to return to one of the questions I have most often dealt with, is the recent revolution in our ideas on mechanics. Will the principle of relativity, as conceived by Lorentz, not impose … Read More

The adventures of a red ant: X. ASSAULT – CARNAGE
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And we walked, with me carried, in front of the liberators! “Urbain!“ said one of the young men, laughing, “deliverance is near!“ “And bites too!“ replied the brave captain. Soon we arrived at the crest of a hill that was … Read More

The adventures of a red ant: IX. IN BRAZIL – I FIND URBAIN
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It was not as difficult as I supposed. I had only to take the path of the cockroaches: they entered the night over the door, I went out the day there. Immediately I reached the leg of a sailor, who … Read More

Henri Poincaré, The evolution of laws (11)
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So far we have not seemed to worry about whether laws actually vary, but only if men can believe them to be variable. Are laws considered to exist outside the mind that creates or observes them immutable in themselves? Not … Read More

The adventures of a red ant: VIII. THE NIGHT MONSTERS – IN A TOOTHPICK
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Sugar was not lacking on the commercial port, because I took care not to waste my time on the military port: the balls, the cannons and the rest will always be a pitiful treat for the ants! So here I … Read More

Henri Poincaré, The evolution of laws (10)
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Thus there is not a single law that we can state with the certainty that it has always been true in the past with the same approximation as today, I will say more, with the certainty that we will never … Read More

The adventures of a red ant: VII. THE TERMITES – THE QUEEN
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The next morning I found myself in an old hotel in Rochefort, where the two brothers had returned. Wrapped in the tablecloths at night, I did not try to regiment myself: it would have been useless. I let myself be … Read More

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