

Would his system still have worked? Would he still have been able to precisely specify the path of the fly? … in other words, the corners were not perpendicular?

Now, here is a key question: what if the walls of Descartes’ room had not been square? The value of a coordinate system is that it gives a unique name to each point in the plane (or in any vector space). The study of curves and shapes in algebraic form laid important groundwork for calculus, and Newton was strongly influenced by Descartes’ ideas. Descartes argued that a triangle could be copied exactly by simply knowing the coordinates of its vertices. For example, the problem of copying a triangle was one that the Greeks had studied and solved using non-numeric methods. This was an important shift in thinking the mathematical tradition begun by the Greeks held that geometry, as practiced by Euclid with compass and straightedge, was a more fundamental approach. What is certain is that Descartes championed the idea that geometric problems could be cast into algebraic form and solved in that fashion. This gave birth to the so-called Cartesian coordinate system.
#Codimension of a subspace definition how to
He thought about how to describe the movement of the fly, and realized that he could completely describe it by measuring its distance from the walls of the room. Then, for example, there are no topological singularities of codimension 2. Equivalently, the codimension of a hypersurface is one. Codimension one cycles modulo rational equivalence form the classical group of divisors.

In the theory of support of codimension at least two. The story goes that one day as he lay in bed, he observed a fly on the ceiling of his room. Again, the analogous statement fails for higher-codimension subvarieties. He is often credited with developing the idea of a coordinate system, although versions of coordinate systems had been seen in Greek mathematics since 300BC.Īs a young man, Descartes had health problems and generally stayed in bed late each day. Rene Descartes (1596-1650) was a French philosopher, mathematician, and writer. Licensed under Public Domain via Wikimedia Commons. "Frans Hals - Portret van René Descartes" by After Frans Hals (1582/1583–1666) - André Hatala (1997) De eeuw van Rembrandt, Bruxelles: Crédit communal de Belgique, ISBN 2-90.
