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Chaos in hyperspaces of nonautonomous discrete systems Hugo - - PowerPoint PPT Presentation

Chaos in hyperspaces of nonautonomous discrete systems Hugo Villanueva Mndez Joint work with Ivn Snchez and Manuel Sanchis Facultad de Ciencias en Fsica y Matemticas Universidad Autnoma de Chiapas Mxico Twelfth Symposium on


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Chaos in hyperspaces of nonautonomous discrete systems

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis

Facultad de Ciencias en Física y Matemáticas Universidad Autónoma de Chiapas México

Twelfth Symposium on General Topology and its Relations to Modern Analysis and Algebra 2016

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Hyperspaces of continua

Definition Given a topological space X, let fn : X → X be a continuous function for each positive integer n. Denote by f∞ the sequence (f1, f2, . . .). We say that the pair (X, f∞) is the nonautonomous discrete dynamical system (NDS, for short) in which the orbit of a point x ∈ X under f∞ is defined as the set

  • rb(x, f∞) = {x, f1(x), f 2

1 (x), . . . , f n 1 (x), . . .},

where f n

1 := fn ◦ fn−1 ◦ · · · ◦ f2 ◦ f1,

for each positive integer n. In particular, when f∞ is the constant sequence (f , f , . . . , f , . . .), the pair (X, f∞) is the usual (autonomous) discrete dynamical system given by the continuous function f on X and it will denoted by (X, f ).

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Hyperspaces of continua

Definition Given a topological space X, let fn : X → X be a continuous function for each positive integer n. Denote by f∞ the sequence (f1, f2, . . .). We say that the pair (X, f∞) is the nonautonomous discrete dynamical system (NDS, for short) in which the orbit of a point x ∈ X under f∞ is defined as the set

  • rb(x, f∞) = {x, f1(x), f 2

1 (x), . . . , f n 1 (x), . . .},

where f n

1 := fn ◦ fn−1 ◦ · · · ◦ f2 ◦ f1,

for each positive integer n. In particular, when f∞ is the constant sequence (f , f , . . . , f , . . .), the pair (X, f∞) is the usual (autonomous) discrete dynamical system given by the continuous function f on X and it will denoted by (X, f ).

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Hyperspaces of continua

Definition Given a topological space X, let fn : X → X be a continuous function for each positive integer n. Denote by f∞ the sequence (f1, f2, . . .). We say that the pair (X, f∞) is the nonautonomous discrete dynamical system (NDS, for short) in which the orbit of a point x ∈ X under f∞ is defined as the set

  • rb(x, f∞) = {x, f1(x), f 2

1 (x), . . . , f n 1 (x), . . .},

where f n

1 := fn ◦ fn−1 ◦ · · · ◦ f2 ◦ f1,

for each positive integer n. In particular, when f∞ is the constant sequence (f , f , . . . , f , . . .), the pair (X, f∞) is the usual (autonomous) discrete dynamical system given by the continuous function f on X and it will denoted by (X, f ).

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Hyperspaces of continua

Definition Given a topological space X, let fn : X → X be a continuous function for each positive integer n. Denote by f∞ the sequence (f1, f2, . . .). We say that the pair (X, f∞) is the nonautonomous discrete dynamical system (NDS, for short) in which the orbit of a point x ∈ X under f∞ is defined as the set

  • rb(x, f∞) = {x, f1(x), f 2

1 (x), . . . , f n 1 (x), . . .},

where f n

1 := fn ◦ fn−1 ◦ · · · ◦ f2 ◦ f1,

for each positive integer n. In particular, when f∞ is the constant sequence (f , f , . . . , f , . . .), the pair (X, f∞) is the usual (autonomous) discrete dynamical system given by the continuous function f on X and it will denoted by (X, f ).

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Definitions

Definition A NDS (X, f∞) is topologically transitive if for any two non-empty open sets U and V in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅;

said to satisfy Banks’ condition if for any three non-empty open sets U, V , W in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅ and f k 1 (U) ∩ W = ∅;

weakly mixing if for any four non-empty open sets U1, U2, V1, V2 in X, there exists a positive integer k such that f k

1 (Ui) ∩ Vi = ∅, for

each i ∈ {1, 2}. If (X, f∞) is weakly mixing, then it has Banks’ condition and, this implies that it is transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Definitions

Definition A NDS (X, f∞) is topologically transitive if for any two non-empty open sets U and V in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅;

said to satisfy Banks’ condition if for any three non-empty open sets U, V , W in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅ and f k 1 (U) ∩ W = ∅;

weakly mixing if for any four non-empty open sets U1, U2, V1, V2 in X, there exists a positive integer k such that f k

1 (Ui) ∩ Vi = ∅, for

each i ∈ {1, 2}. If (X, f∞) is weakly mixing, then it has Banks’ condition and, this implies that it is transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Definitions

Definition A NDS (X, f∞) is topologically transitive if for any two non-empty open sets U and V in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅;

said to satisfy Banks’ condition if for any three non-empty open sets U, V , W in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅ and f k 1 (U) ∩ W = ∅;

weakly mixing if for any four non-empty open sets U1, U2, V1, V2 in X, there exists a positive integer k such that f k

1 (Ui) ∩ Vi = ∅, for

each i ∈ {1, 2}. If (X, f∞) is weakly mixing, then it has Banks’ condition and, this implies that it is transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Definitions

Definition A NDS (X, f∞) is topologically transitive if for any two non-empty open sets U and V in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅;

said to satisfy Banks’ condition if for any three non-empty open sets U, V , W in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅ and f k 1 (U) ∩ W = ∅;

weakly mixing if for any four non-empty open sets U1, U2, V1, V2 in X, there exists a positive integer k such that f k

1 (Ui) ∩ Vi = ∅, for

each i ∈ {1, 2}. If (X, f∞) is weakly mixing, then it has Banks’ condition and, this implies that it is transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Definitions

Definition A NDS (X, f∞) is topologically transitive if for any two non-empty open sets U and V in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅;

said to satisfy Banks’ condition if for any three non-empty open sets U, V , W in X, there exists a positive integer k such that f k

1 (U) ∩ V = ∅ and f k 1 (U) ∩ W = ∅;

weakly mixing if for any four non-empty open sets U1, U2, V1, V2 in X, there exists a positive integer k such that f k

1 (Ui) ∩ Vi = ∅, for

each i ∈ {1, 2}. If (X, f∞) is weakly mixing, then it has Banks’ condition and, this implies that it is transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Definitions

Let X be a topological space. The symbol K(X) will denote the hyperspace of all non-empty compact subsets of X endowed with the Vietoris topology. Induced NDS Given a continuous function f : X → X, it induces a continuous function

  • n K(X), f : K(X) → K(X) defined by f (K) = f (K) for every

K ∈ K(X). Let (X, f∞) be a NDS and fn the induced continuous function of fn on K(X), for each positive integer n. Then, the sequence f∞ = (f1, f2, . . . , fn, . . .) induces a nonautonomous discrete dynamical system (K(X), f∞). In this case, f

n 1 = fn ◦ · · · ◦ f2 ◦ f1.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Definitions

Let X be a topological space. The symbol K(X) will denote the hyperspace of all non-empty compact subsets of X endowed with the Vietoris topology. Induced NDS Given a continuous function f : X → X, it induces a continuous function

  • n K(X), f : K(X) → K(X) defined by f (K) = f (K) for every

K ∈ K(X). Let (X, f∞) be a NDS and fn the induced continuous function of fn on K(X), for each positive integer n. Then, the sequence f∞ = (f1, f2, . . . , fn, . . .) induces a nonautonomous discrete dynamical system (K(X), f∞). In this case, f

n 1 = fn ◦ · · · ◦ f2 ◦ f1.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Definitions

Let X be a topological space. The symbol K(X) will denote the hyperspace of all non-empty compact subsets of X endowed with the Vietoris topology. Induced NDS Given a continuous function f : X → X, it induces a continuous function

  • n K(X), f : K(X) → K(X) defined by f (K) = f (K) for every

K ∈ K(X). Let (X, f∞) be a NDS and fn the induced continuous function of fn on K(X), for each positive integer n. Then, the sequence f∞ = (f1, f2, . . . , fn, . . .) induces a nonautonomous discrete dynamical system (K(X), f∞). In this case, f

n 1 = fn ◦ · · · ◦ f2 ◦ f1.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Background

  • Theorem. (Peris, 2004)

Let f : X → X be a continuous function on a topological space X. Then the following conditions are equivalent: (1) (X, f ) is weakly mixing. (2) (K(X), f ) is weakly mixing. (3) (K(X), f ) is transitive. (2) implies (3) even in nonautonomous discrete dynamical systems.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Background

  • Theorem. (Peris, 2004)

Let f : X → X be a continuous function on a topological space X. Then the following conditions are equivalent: (1) (X, f ) is weakly mixing. (2) (K(X), f ) is weakly mixing. (3) (K(X), f ) is transitive. (2) implies (3) even in nonautonomous discrete dynamical systems.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Background

  • Theorem. (Peris, 2004)

Let f : X → X be a continuous function on a topological space X. Then the following conditions are equivalent: (1) (X, f ) is weakly mixing. (2) (K(X), f ) is weakly mixing. (3) (K(X), f ) is transitive. (2) implies (3) even in nonautonomous discrete dynamical systems.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Background

  • Theorem. (Peris, 2004)

Let f : X → X be a continuous function on a topological space X. Then the following conditions are equivalent: (1) (X, f ) is weakly mixing. (2) (K(X), f ) is weakly mixing. (3) (K(X), f ) is transitive. (2) implies (3) even in nonautonomous discrete dynamical systems.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Example

Example There is a NDS (I, f∞) which is weakly mixing, but (K(I), f∞) is not transitive. Let F = {(a, b, c, d) ∈ Q4 : a, b, c, d ∈ (0, 1), a < b, a = c, b = d, c = d}. Clearly, F is countable. We will assign a homeomorphism f : I → I to every element (a, b, c, d) ∈ F as follows: Case 1. If c < d, then f is the function whose graphic is determined by the segments [(0, 0), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 1)]. Case 2. If c > d, then f is the function whose graphic is determined by the segments [(0, 1), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 0)].

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Example

Example There is a NDS (I, f∞) which is weakly mixing, but (K(I), f∞) is not transitive. Let F = {(a, b, c, d) ∈ Q4 : a, b, c, d ∈ (0, 1), a < b, a = c, b = d, c = d}. Clearly, F is countable. We will assign a homeomorphism f : I → I to every element (a, b, c, d) ∈ F as follows: Case 1. If c < d, then f is the function whose graphic is determined by the segments [(0, 0), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 1)]. Case 2. If c > d, then f is the function whose graphic is determined by the segments [(0, 1), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 0)].

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Example

Example There is a NDS (I, f∞) which is weakly mixing, but (K(I), f∞) is not transitive. Let F = {(a, b, c, d) ∈ Q4 : a, b, c, d ∈ (0, 1), a < b, a = c, b = d, c = d}. Clearly, F is countable. We will assign a homeomorphism f : I → I to every element (a, b, c, d) ∈ F as follows: Case 1. If c < d, then f is the function whose graphic is determined by the segments [(0, 0), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 1)]. Case 2. If c > d, then f is the function whose graphic is determined by the segments [(0, 1), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 0)].

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Example

Example There is a NDS (I, f∞) which is weakly mixing, but (K(I), f∞) is not transitive. Let F = {(a, b, c, d) ∈ Q4 : a, b, c, d ∈ (0, 1), a < b, a = c, b = d, c = d}. Clearly, F is countable. We will assign a homeomorphism f : I → I to every element (a, b, c, d) ∈ F as follows: Case 1. If c < d, then f is the function whose graphic is determined by the segments [(0, 0), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 1)]. Case 2. If c > d, then f is the function whose graphic is determined by the segments [(0, 1), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 0)].

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Example

Example There is a NDS (I, f∞) which is weakly mixing, but (K(I), f∞) is not transitive. Let F = {(a, b, c, d) ∈ Q4 : a, b, c, d ∈ (0, 1), a < b, a = c, b = d, c = d}. Clearly, F is countable. We will assign a homeomorphism f : I → I to every element (a, b, c, d) ∈ F as follows: Case 1. If c < d, then f is the function whose graphic is determined by the segments [(0, 0), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 1)]. Case 2. If c > d, then f is the function whose graphic is determined by the segments [(0, 1), (a, c)], [(a, c), (b, d)] and [(b, d), (1, 0)].

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Example

In both cases f (a) = c and f (b) = d. Let {fn : n ∈ N} be an enumeration of the functions induced by the elements of F. Consider f∞ = (f1, f −1

1

, f2, f −1

2

, ..., fn, f −1

n

, ...). (I, f∞) is weakly mixing and (K(I), f∞) is not transitive. Example There is a NDS (I, f∞) such that (K(I), f∞) is transitive, but (I, f∞) is not weakly mixing.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Example

In both cases f (a) = c and f (b) = d. Let {fn : n ∈ N} be an enumeration of the functions induced by the elements of F. Consider f∞ = (f1, f −1

1

, f2, f −1

2

, ..., fn, f −1

n

, ...). (I, f∞) is weakly mixing and (K(I), f∞) is not transitive. Example There is a NDS (I, f∞) such that (K(I), f∞) is transitive, but (I, f∞) is not weakly mixing.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Example

In both cases f (a) = c and f (b) = d. Let {fn : n ∈ N} be an enumeration of the functions induced by the elements of F. Consider f∞ = (f1, f −1

1

, f2, f −1

2

, ..., fn, f −1

n

, ...). (I, f∞) is weakly mixing and (K(I), f∞) is not transitive. Example There is a NDS (I, f∞) such that (K(I), f∞) is transitive, but (I, f∞) is not weakly mixing.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Example

In both cases f (a) = c and f (b) = d. Let {fn : n ∈ N} be an enumeration of the functions induced by the elements of F. Consider f∞ = (f1, f −1

1

, f2, f −1

2

, ..., fn, f −1

n

, ...). (I, f∞) is weakly mixing and (K(I), f∞) is not transitive. Example There is a NDS (I, f∞) such that (K(I), f∞) is transitive, but (I, f∞) is not weakly mixing.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

Banks proved that in autonomous discrete dynamical systems the property of being weakly mixing is equivalent to satisfy Banks’ condition. Theorem If (K(X), f∞) is transitive, then (X, f∞) satisfies Banks’ condition. Proposition If (K(X), f∞) is transitive, then so is (X, f∞). Proposition If (K(X), f∞) is weakly mixing, then so is (X, f∞).

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

Banks proved that in autonomous discrete dynamical systems the property of being weakly mixing is equivalent to satisfy Banks’ condition. Theorem If (K(X), f∞) is transitive, then (X, f∞) satisfies Banks’ condition. Proposition If (K(X), f∞) is transitive, then so is (X, f∞). Proposition If (K(X), f∞) is weakly mixing, then so is (X, f∞).

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

Banks proved that in autonomous discrete dynamical systems the property of being weakly mixing is equivalent to satisfy Banks’ condition. Theorem If (K(X), f∞) is transitive, then (X, f∞) satisfies Banks’ condition. Proposition If (K(X), f∞) is transitive, then so is (X, f∞). Proposition If (K(X), f∞) is weakly mixing, then so is (X, f∞).

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

Banks proved that in autonomous discrete dynamical systems the property of being weakly mixing is equivalent to satisfy Banks’ condition. Theorem If (K(X), f∞) is transitive, then (X, f∞) satisfies Banks’ condition. Proposition If (K(X), f∞) is transitive, then so is (X, f∞). Proposition If (K(X), f∞) is weakly mixing, then so is (X, f∞).

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

Definition We say that (X, f∞) is weakly mixing of order m (m ≥ 2) if for any non-empty open sets U1, U2, ..., Um, V1, V2, ..., Vm in X, there exists a positive integer k such that f k

1 (Ui) ∩ Vi = ∅ for each i ∈ {1, 2, ..., m}.

Theorem Suppose that (K(X), f∞) is weakly mixing of order m. Then so is (X, f∞). Theorem (I, f∞) is weakly mixing of order 3 if and only if (K(I), f∞) is weakly mixing of order 3.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

Definition We say that (X, f∞) is weakly mixing of order m (m ≥ 2) if for any non-empty open sets U1, U2, ..., Um, V1, V2, ..., Vm in X, there exists a positive integer k such that f k

1 (Ui) ∩ Vi = ∅ for each i ∈ {1, 2, ..., m}.

Theorem Suppose that (K(X), f∞) is weakly mixing of order m. Then so is (X, f∞). Theorem (I, f∞) is weakly mixing of order 3 if and only if (K(I), f∞) is weakly mixing of order 3.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

Definition We say that (X, f∞) is weakly mixing of order m (m ≥ 2) if for any non-empty open sets U1, U2, ..., Um, V1, V2, ..., Vm in X, there exists a positive integer k such that f k

1 (Ui) ∩ Vi = ∅ for each i ∈ {1, 2, ..., m}.

Theorem Suppose that (K(X), f∞) is weakly mixing of order m. Then so is (X, f∞). Theorem (I, f∞) is weakly mixing of order 3 if and only if (K(I), f∞) is weakly mixing of order 3.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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On Devaney chaos

Definition Given a NDS (X, f∞), a point x ∈ X is periodic if f n

1 (x) = x for some

positive integer n. Let us denote by Per(f∞) the set of periodic points of f∞. Definition Let (X, d) be a metric space. We say that (X, f∞) has sensitive dependence on initial conditions if there exists δ > 0 such that for every point x and every open neighborhood U of x, there exist y ∈ U and n ∈ N such that d(f n

1 (x), f n 1 (y)) ≥ δ.

Definition Given a metric space X we say that the NDS (X, f∞) is Devaney chaotic if it is transitive, sensitive and has dense set of periodic points.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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On Devaney chaos

Definition Given a NDS (X, f∞), a point x ∈ X is periodic if f n

1 (x) = x for some

positive integer n. Let us denote by Per(f∞) the set of periodic points of f∞. Definition Let (X, d) be a metric space. We say that (X, f∞) has sensitive dependence on initial conditions if there exists δ > 0 such that for every point x and every open neighborhood U of x, there exist y ∈ U and n ∈ N such that d(f n

1 (x), f n 1 (y)) ≥ δ.

Definition Given a metric space X we say that the NDS (X, f∞) is Devaney chaotic if it is transitive, sensitive and has dense set of periodic points.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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On Devaney chaos

Definition Given a NDS (X, f∞), a point x ∈ X is periodic if f n

1 (x) = x for some

positive integer n. Let us denote by Per(f∞) the set of periodic points of f∞. Definition Let (X, d) be a metric space. We say that (X, f∞) has sensitive dependence on initial conditions if there exists δ > 0 such that for every point x and every open neighborhood U of x, there exist y ∈ U and n ∈ N such that d(f n

1 (x), f n 1 (y)) ≥ δ.

Definition Given a metric space X we say that the NDS (X, f∞) is Devaney chaotic if it is transitive, sensitive and has dense set of periodic points.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

Theorem Let (X, d) be a compact metric space. If (K(X), f∞) has sensitive dependence on initial conditions, then (X, f∞) does. Example There is a NDS (I, f∞) which is transitive and has dense set of periodic points, but it does not have sensitive dependence on initial conditions.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

Theorem Let (X, d) be a compact metric space. If (K(X), f∞) has sensitive dependence on initial conditions, then (X, f∞) does. Example There is a NDS (I, f∞) which is transitive and has dense set of periodic points, but it does not have sensitive dependence on initial conditions.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

A NDS (X, f∞) is said to be point transitive if there exists x ∈ X with dense orbit in X. Proposition If (K(X), f∞) is point transitive, then so is (X, f∞). It is known that point transitivity is equivalent to transitivity for autonomous discrete dynamical systems on complete separable metric spaces without isolated points. Proposition Suppose that X is a second-countable space with the Baire property. If (X, f∞) is transitive, then it is point transitive. Example There is a NDS (I, g∞) which is point transitive but it is not transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

A NDS (X, f∞) is said to be point transitive if there exists x ∈ X with dense orbit in X. Proposition If (K(X), f∞) is point transitive, then so is (X, f∞). It is known that point transitivity is equivalent to transitivity for autonomous discrete dynamical systems on complete separable metric spaces without isolated points. Proposition Suppose that X is a second-countable space with the Baire property. If (X, f∞) is transitive, then it is point transitive. Example There is a NDS (I, g∞) which is point transitive but it is not transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

A NDS (X, f∞) is said to be point transitive if there exists x ∈ X with dense orbit in X. Proposition If (K(X), f∞) is point transitive, then so is (X, f∞). It is known that point transitivity is equivalent to transitivity for autonomous discrete dynamical systems on complete separable metric spaces without isolated points. Proposition Suppose that X is a second-countable space with the Baire property. If (X, f∞) is transitive, then it is point transitive. Example There is a NDS (I, g∞) which is point transitive but it is not transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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SLIDE 42

Results

A NDS (X, f∞) is said to be point transitive if there exists x ∈ X with dense orbit in X. Proposition If (K(X), f∞) is point transitive, then so is (X, f∞). It is known that point transitivity is equivalent to transitivity for autonomous discrete dynamical systems on complete separable metric spaces without isolated points. Proposition Suppose that X is a second-countable space with the Baire property. If (X, f∞) is transitive, then it is point transitive. Example There is a NDS (I, g∞) which is point transitive but it is not transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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SLIDE 43

Results

A NDS (X, f∞) is said to be point transitive if there exists x ∈ X with dense orbit in X. Proposition If (K(X), f∞) is point transitive, then so is (X, f∞). It is known that point transitivity is equivalent to transitivity for autonomous discrete dynamical systems on complete separable metric spaces without isolated points. Proposition Suppose that X is a second-countable space with the Baire property. If (X, f∞) is transitive, then it is point transitive. Example There is a NDS (I, g∞) which is point transitive but it is not transitive.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Results

  • M. Vellekoop and R. Berglund showed (1994) that for autonomous

discrete dynamical systems on the unit interval I to be Devaney chaotic is equivalent to be transitive Example There is a transitive NDS (I, g∞) with sensitive dependence on initial conditions such that the set of periodic points is not dense in I.

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems

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Thank you!

Hugo Villanueva Méndez Joint work with Iván Sánchez and Manuel Sanchis Chaos in hyperspaces of nonautonomous discrete systems