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2 votes
0 answers
74 views

Is it likely that gradient flow trajectories of a $G$-invariant function pass through degenerate points?

This question may be posed somewhat vaguely, but I'm interested to actually get an idea of what to expect, so I try to not target it at a specific result. Assume that $G$ is a compact Lie group, ...
Whatsumitzu's user avatar
4 votes
0 answers
148 views

Exponential map for tangent space of space of distributions $\mathscr{P}_2(X)$

In Chapter 8 of the book Gradient Flows In Metric Spaces and in the Space of Probability Measures by Ambrosio et al., the tangent space to the space of distributions on $X$ (let's say $X=\mathbb{R}^d$)...
Juno Kim's user avatar
2 votes
1 answer
291 views

When does uniqueness of a stable equilibrium imply it is globally stable?

Given a gradient dynamical system $$\dot x=-\nabla f(x),$$ my question is: (1) If there exists only one equilibrium $x^*$ which is stable (if necessary, this can be changed to stable asymptotically ...
tony's user avatar
  • 405
1 vote
1 answer
181 views

Gradient descent under the presence of symmetries

Let $M$ be a Riemannian manifold (I'm happy to assume it is Euclidean space) with a function $f: M \to \mathbb R$ and a group of isometries $G$ acting on $M$ and preserving $f$, i.e., $f(gm) = f(m)$ ...
Asvin's user avatar
  • 7,746
3 votes
0 answers
93 views

Regularity of center manifold

Consider a $C^r$ vector field $f \colon \mathbb{R}^n \to \mathbb{R}^n$ with $r \geq 1$. Let $\bar x$ be a critical point of $f$, that is, $f(\bar x) = 0$. Suppose that the spectrum of $\mathrm{D}f(\...
Sap's user avatar
  • 31
0 votes
0 answers
223 views

Convergence of ODE solutions almost everywhere to a stable equilibrium point

Theorem: Suppose ${\bf g} :\mathbb{R}^n \mapsto \mathbb{R}^n$ is continuously differentiable, there exists a set $\mathcal{A} \subset \mathbb{R}^n$ such that $\bf g$ is uniformly Lipschitz on $\...
RLip2's user avatar
  • 1
2 votes
0 answers
65 views

Chain recurrent points of a gradient-like system

Let $X$ be a compact metric space and $f:X\to X $ homeomorphism. Let $V:X\to \mathbb{R}$ be a Lyapunov function for $(X,f)$ (continuous function such that $(\forall x\notin Fix(f))\ \ V(f(x))<V(x))...
blue's user avatar
  • 141
1 vote
1 answer
169 views

Gradient-like dynamical systems

I've tried asking this question on Mathematics site, but I only got an upvote and no answer. I've searched online, tried to find something about this topic, but I haven't found much (and the things I ...
blue's user avatar
  • 141
5 votes
0 answers
140 views

What kinds of gradient-flows on $\mathbb R^d$ preserve the log-concavity of the distribution $\mu_0$ of starting point $x_0$

Let $\mu_0$ be a log-concave distribution on $\mathbb R^d$ and let $f:\mathbb R^d \to \mathbb R$ be $C^2$. Let $x_0$ be sampled uniformly at random from a log-concave distribution $\mu_0$, meaning ...
dohmatob's user avatar
  • 6,853
5 votes
3 answers
643 views

What quantities are conserved under a general gradient-flow $\dot X(t) = -\nabla L(X(t))$?

Let $L:\mathbb R^N \to \mathbb R$ be a continuously differential function with gradient $x \mapsto \nabla L(x)$ and consider induced gradient-flow $$ \dot X(t) = -\nabla L(X(t)). $$ Question. Is ...
dohmatob's user avatar
  • 6,853
2 votes
0 answers
83 views

Center-stable manifold theorem on manifold with boundary

I would like to see if there is a Center-stable manifold theorem on the phase space that is a manifold with boundary. Suppose $f:M\rightarrow M$ is a diffeomorphism, according to Theorem III.7 in "...
Xiiao's user avatar
  • 21
5 votes
0 answers
281 views

Basin of attraction of gradient flow

Suppose we have a compact Riemannian manifold $(M,g)$, and a Morse function $f : M \rightarrow \mathbb{R}$. Suppose we consider the gradient flow generated by this function, i.e. $$\dot{x_t} = - \...
Rikimaru's user avatar
  • 151