Christophe Tardy
Christophe Tardy
Posted on June 7, 2004
the transformation of a Cross Cap into a Boy's surface, via the Roman surface of Steiner.
Christophe became "Christopher Lent" in my book "L'Année du Contact" (Albin Michel 2004). When I suggested this to him, he said, "Great, I'll become a science fiction character!" A few years ago, Christophe helped me put some elements of
, virtual reality, on my website. I recommend you take a look. It's worth the detour. He's a real expert in CAD.
We had thought, Christophe and I, to one day get back to the search for the correct implicit equation of the Boy's surface (not the one of Apéry, which is too complicated). We had an idea of how to proceed. But, in the end, the world of science is quite dreary. When it's quick and easy, it's fine. When there's work, you can wonder if it's really worth it to struggle for these people. The last time Tardy accompanied me, it was in Marseille, when I gave a seminar in a geometry department, on
We were rather bored. The mathematicians were very stiff. None of them had ever encountered a Steiner surface on the street. I finally said, "Who has ever seen a Roman surface of Steiner? Raise your hand..."
tardy.c@wanadoo.fr
as a response. Christophe then took out his phone and we offered them to see the object, in virtual reality. In the folder,
I told them:
- Come on, don't hesitate! Rotate the surface before your eyes!
It took some insistence for them to dare to touch the mouse. In short, we were bored. I had spread out a bunch of models in front of them. At one point, one of the mathematicians said:
-
If I understand correctly, if I go from left to right, I can chain a sequence of geometric transformations that allow me to go from the Cross Cap to the Boy's surface, right or left, at will.
-
Exactly.
-
But then I can also start from the Boy's surface and transform it into a Cross Cap by taking the transformations in reverse?
-
Exactly. And you can even stop halfway and turn back when you reach the Roman surface of Steiner, thus transforming a "right" Boy's surface into a "left" Boy's surface.
I had Christophe confirm the accuracy of this question on the way back, and the mathematician had thus discovered that a geometric transformation is not essentially reversible. But the most beautiful moment was when the mathematician, scratching his head, doubted my statements by exclaiming, "But I don't see why Petit uses such complicated transformations to swap the two cusp points of a Cross Cap. For me, it's trivial," and he drew a flattened sphere between two lines.
A moment of silence. Suddenly, one of his colleagues said to him, "Hey, your surface is two-sided." And that's when Tardy, who never misses an opportunity to stir things up, said:
- It might be a two-sided Cross Cap.
The opponent turned red and went back to his seat. It's because the Cross Cap, like the Klein bottle, is a fundamentally one-sided object, with only one side. Christophe's remark was equivalent to saying, "It might be a two-sided Klein bottle."
One thing is certain: we will never be invited back.
By the way, Christophe was the first to "make speak" the "Egyptian elbow" displayed in room VI at the Louvre Museum (have you seen its irregular graduations)?
Great intuition. I thought, "Ah, the CNRS would really need people like him!" But it's impossible. If you are imaginative and creative, you will never be hired. The little friends of the committees would immediately block you. That's why this giant continues to sink, despite the efforts of the few talented people who inhabit it. I found another application of this rule. We had considered publishing it in an Egyptology journal. But, since it was made clear to us that this discipline falls under "human sciences," we didn't even feel like trying (it's obvious there's some math involved here).
I think Christophe would have been hired by the chief engineer in charge of building the pyramids. But you can't choose your era.
Recently laid off (May 2004), Christophe was dismissed a month ago.
Managers of companies in the PACA region, are you looking for a young engineer from Arts et Métiers, hardworking, brilliant and kind, capable of doing anything? Contact him at:
Back to "Gallery of Portraits" Back to Guide Back to Home Page
Number of views since June 7, 2004 :