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2 votes
1 answer
139 views

Can a chaotic trajectory solve an algebraic equation?

Given a polynomial ODE in $n$-dimensions of maximal degree $d$ $$\dot{x}_j=f_j(x)=\sum_{i_{1},\dots,i_{n}=1}^{d}a_{i_{1},\dots,i_{n}}^{j}x_{1}^{i_{1}}\dots x_{n}^{i_{n}} \quad \forall j=1,...,n$$ we ...
23 votes
5 answers
2k views

PDEs and algebraic varieties

Let $P$ be an order $d$ differential operator with constant coefficients and consider a PDE of the form $Pf = \delta$. Taking the Fourier transform of $P$ we get a degree $d$ polynomial whose zero ...
4 votes
0 answers
126 views

Darboux integral for non-polynomial ODEs

Given a polynomial ODE in $n$-dimensions of maximal degree $d$ $$ \dot{x}_j=f_j(x)=\sum_{i_1,\dots,i_n=1}^d a_{i_1,\dots,i_n}^j x_1^{i_1}\dots x_n^{i_n} \quad \forall j=1,\ldots,n $$ we define ...
1 vote
0 answers
37 views

Unique smallest degree algebraic solution to polynomial ODE

Let's assume we are given a degree $d$ polynomial VF as a map $f: \mathbb{R}^n \rightarrow \mathbb{R}^n$ $$f_j(x)=\sum_{i_{1},\dots,i_{n}=1}^{d}a^j_{i_{1},\dots,i_{n}}x_{1}^{i_{1}}\dots x_{n}^{i_{n}}$$...
7 votes
1 answer
299 views

Spaces of solutions to algebraic linear differential equations

What is the name of the function space formed by solutions to algebraic linear differential equations? Where can I find a discussion of its properties? By an algebraic linear differential equation I ...