Category: Dictionaries

But what is a continuum with n dimensions; how does it differ from a continuum whose number of dimensions is larger or smaller? First, let us recall some results recently obtained by the students of Cantor. It is possible to … Read More

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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

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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

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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

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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

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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

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Let us return to our imaginary world and ask ourselves if its inhabitants could not, without renewing the history of the sleepers of Ephesus, perceive this evolution. No doubt, no matter how perfect the heat conductivity on their planet, it … Read More

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I suppose a world whose various parts possess a heat conductivity so perfect that they are constantly in equilibrium of temperature. The inhabitants of this world would have no idea of ​​what we call temperature difference; in their treatises on … Read More

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Let us now turn to another point of view. The laws that direct observation gives us are never more than results. Take for example the law of Mariotte. For most physicists, this is only a consequence of the kinetic theory … Read More

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And if humanity were to last longer than we have supposed, long enough to see the laws evolve before its eyes? Or even if it came to acquire instruments delicate enough that this variation, slow as it is, becomes sensitive … Read More

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