BENOIT RITTAUD
40 articles published in Tangente
Math for everyoneN°89Feb 20, 2024The people of the rational numbers
A brief imaginary, non-chronological history that attempts to answer a question less straightforward than it seems: are fractions numbers?
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Everyday MathN°89Feb 12, 2024Editorial
How long is a fraction of a second? In everyday life, we would simply say that it is a very short time; in mathematics, however, we would be led to look for two integers—a numerator and a larger denominator—with which to quantify it.
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Math for everyoneN°72Oct 09, 2019D'Arcy Thompson and the geometry of nature
Can the forms we see in nature be explained mathematically? Physics has had its principle of least action since Maupertuis in the 18th century, but biology had to wait until the early 20th century for anyone to attempt a synthesis.
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Math for everyoneN°72Oct 09, 2019Using the derivative to hit bottom
Finding the lowest point on a given curve requires considering how the curve is approximated by a line near one of its points. This is where the tangent enters the picture
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Math for everyoneN°72Oct 09, 2019Hills and valleys
A real-life situation or a physics experiment generally depends on several parameters, not just one. We therefore need a deeper understanding of variation in this multidimensional setting. Partial derivatives provide just that.
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KnowledgeSep 19, 2019The dyadic tree
An infinite tree can be used to construct either the positive integers or the dyadic integers. The trick is to choose carefully where to put the 0s and 1s.
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Math for everyoneSep 19, 2019The dyadic tree
Starting from a tree whose leaves extend indefinitely, we can construct either the positive integers or the dyadic integers. The trick? Put the 0s and 1s in the right places.
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N°71Jul 09, 2019Minkowski space
How can the "strangeness" of relativity be described geometrically? By introducing a time dimension and mathematically redefining distance, Minkowski space provides the rigorous framework we need.
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InterviewN°70Apr 11, 2019The geoid, a unique surface
The surface most familiar to us, the one we walk on every day, raises its fair share of questions: what exactly is the shape of the Earth? It is neither quite a sphere nor an ellipsoid. This irregular object, the geoid, has some subtle properties. We spoke with a specialist.
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KnowledgeN°70Apr 11, 2019Worlds without thickness
First defined as parts of space described using two parameters, surfaces can also be viewed as worlds in their own right: self-contained universes whose intrinsic properties can be studied without looking at them from the outside.
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Math for everyoneN°70Apr 11, 2019A little terminology…
Everyday language often conflates the notions of surface and area.
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Math for everyoneN°68Oct 12, 2018Major mathematical concepts in computational form
Will machines replace human beings? Will artificial intelligence prove better than us in every field? Gérard Berry reassures us on at least one point: computers are nowhere near supplanting mathematical ingenuity…
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