Hyperbolic

(Thurston-Sullivan?) Are all smooth actions of Φg on S1 which are topologically conjugate to a standard one differentiably conjugate to the standard one?

φt:T1MT1M Anosov geodesic flow and V:MR such that V(πφtx)=0 on every closed geodesic. Is V identically 0?

T:MMC Anosov. fCr and f(x)=u(x)u(Tx).   Does  uCr? (r2).

  1. Subshifts of finite type have good quotients with fixed points.
  2. Given a periodic point p  in Ωi, is there a Markov partition with p in the interior of a rectangle?
  3. If sC does sC contain a periodic point?
  4. Do two subshifts of finite type with the same entropy have a common good quotient?
  5. ΣA,ΣB aperiodic, h(σA)<h(σB). Does σA|ΣA embed in σB|ΣB?

Question 136 with expansive instead of hyperbolic.

For most C2 maps f:[0,1][0,1], for all ϵ>0 there is a hyperbolic set Λ such that h(f|Λ)h(f)ϵ. (See question 8c.)

Embedding algebraic variety over Zp into  a basic set.

Weil conjecture for basic sets.

Cancellation theorem for basic sets. Analogue of cobordism theorem.

(Thom) GradF for real analytic F:RnR. Stratification of orbits near a singular point.

(Sullivan) Show that |λ|=1 for f:MM, where f is  C1 and distal and λ is an eigenvalue of f. Is fg for some Morse Smale g?

det(IA) as a group invariant for the weak foliation Wwu, seen as a subgroup lying in some Hm(M,S1)?

For a hyperbolic attractor Λ of dimension r, does Ws(x)Λcontain a disk of dimension k:=rDimWu(x)?

Central Limit Theorem for β-transform x(βx).

Embed automorphisms of compact groups as basic sets.

 Note: 11t=Πn=0(1+t2n) in Z[[t]]. Is there a C2 map D2D2 so that.....

How can you write 1+t+t2=Πi=0(1±tni) in Z[[t]]?

Is the false zeta function of a basic set ....? Define false zeta function for a flow basic set

If a C1 Anosov preserves a smooth measure, is it an equilibrium state for logλu?

(Doug (Lind?)) Find open partitions in Σ1/2,1/2 that are not weakly Bernoulli. Find invariants of finitary codes.

Example of a non-ergodic C1 Anosov diffeo on T2 preserving Lebesgue measure.

Does every manifold Mn,n3 admit a smooth Bernoulli flow (Ruelle)?

Among degree n polynomial maps of [0,1] to itself, are Axiom A open and dense. Do bad ones form a stratified set? ...

 

If f is Anosov on M and ˜M contractible, what does Hk(M)(Hk(π1(M))) tell you via f eigenvalue information? (See [1], pp. 200-202)


References

For Anosov flow φt on M, try to approximate curves in M by pseudo-orbits and compute π1(M) . . . as in Morse theory.

Unstable foliations of Anosov diffeos are given by some nilpotent group action.

Reddy examples of expansive maps. Related to Anosov diffeos. Are expansive diffeos likely to be Anosov?

Conditions on M to admit Anosov f

If f is Axiom A, is there an Axiom A g, C0 near f with dimΩ(g)=d and h(f)=h(g)?

If f is Anosov and gf, does h(g)h(f)?

Cancellation of Ωi. Simplest f in an iosotopy class.

Classify all Anosov systems or attractors (which Ωi can occur as attractors?)

Electric circuits

  • Analogue computer for finding Axiom A examples
  • Is noise sometimes due to hyperbolicity in the dynamics?

Computer programs for Axiom A attractor.

Is Gutzwiller's example an Anosov flow?

(fnγ) grows slowly with n for many curves γ and Axiom A diffeos f.

C-dense (mixing) Axiom A flows

  1. speed of mixing
  2. asymptotic expression for the number of periodic orbits
  3. is φ1 intrinsically ergodic?
  4. direct proof of mixing of measures
  5. analogue of h(f)log|λ|
  6. understand det(IdA) as an invariant; relation to ζ(0)
  7. stability of C-density for attractors
  8. condition on g so that ΣA(g) is analytically or C embeddable as a basic set.
  9. can a closed orbit of an Anosov flow be null homotopic?

Is φ1 a continuity point for the entropy as a function of diffeos when φt is Axiom A flow? an Anosov flow?

If a geodesic flow is expansive, is it an Anosov flow?

Anosov diffeos

 

  1. Hypothesis on H1(M)
  2. Fixed points
  3. Ω=M

Find Axiom A infinite attractor in some O.D.E. on R3 (quadratic).

Kupka-Smale plus h(f)>0 forces homoclinic points.

Bifurcation of Axiom A in terms of symbols.

Canonical C0 perturbation of Anosov diffeo to 0-dimensional Ωi's with the same entropy

Canonical embedding of Axiom A Ωi

Assume φt C-dense. If ν is φ1 invariant is ν φ-invariant?

Interpret logλu as a potential function  (Kolmogorov's   idea on surfaces of negative curvature)?

Symbolic dynamics for billiards

Renewal theorems for dependent random variables.

 

  1.  Derive as a motivation for Axiom A flow mixingness
  2.  How fast is the mixing for Axiom A flows?

Suspensions of diffeos. -  Are they generically not  (conjugated to) constant time suspensions? what is the strongest statement for Axiom A attractors?

Shub's entropy conjecture: h(f)log|λ|

  1.  for diffeos
  2.  Ω finite plus hyperbolic
  3.  Axiom A with cycles.

Nonalgebraic Anosov diffeos. Classify 3-dimensional Anosov flows; Is the variable curvature surface geodesic flow conjugate to constant curvature?

Unique ergodicity of Wu for partially Anosov diffeos.

Non Axiom A examples. Newhouse, Abraham-Smale, Simon, Lorenz, billiards.

  1. Axiomatic description
  2. Statistical properties
  3. For all ϵ, there exists a horseshoe Xϵ inside with h(f|Xϵ)h(f)ϵ
  4. Statistical properties of Lorenz in particular
  5. Any specification type property

Structure of basic sets

  1. Classification via (R,A)
  2. Local Axiom A implies embeddable

  3. existence of canonical coordinates implies embeddable (compact abelian group actions ? are Ω's).

  4. Phantom homology groups -shift equivalence of induced maps! 

  5. dim Ω?; when is the quotient a manifold?

Zeta function for Axiom A flows and systems

  1.  topological identification (try 1-dimensional Ω first); conjugacy invariance of ζ(0).
  2. For C flows, ζ(s) has a meromorphic extension to the complex plane.

  3. Connection with Laplacian vs. geodesic results; automorphic forms.

  4. Anosov actions.

Classification of singularities by the local properties of the gradient flow.

To what extent does the gradient flow near a critical point depend on the metric?