Skip to main content
deleted 6 characters in body
Source Link
Pietro Majer
  • 60.6k
  • 4
  • 122
  • 269

I am interested in constructing the following "counter-example" to the Banach's fixed point theorem.

Let $K=$ {$ g\in L_1: \|g\|=1, g(\cdot)\ge0 $}. Clearly, $K$ is not a compact and $K$ is not closed.

My A question is: is it possible to construct a [edit] "weak"nonexpansive contraction mapping $f: K\to K$ with no fixed point? ( i.e. a mapping $f$ such that [edit] for all $x\neq y\in K$ one has $\|f(x)-f(y)\| < \|x-y\|$. )

I am interested in constructing the following "counter-example" to the Banach's fixed point theorem.

Let $K=$ {$ g\in L_1: \|g\|=1, g(\cdot)\ge0 $}. Clearly, $K$ is not a compact and $K$ is not closed.

My A question is: is it possible to construct a [edit] "weak" contraction mapping $f: K\to K$ with no fixed point? ( i.e. a mapping $f$ such that [edit] for all $x\neq y\in K$ one has $\|f(x)-f(y)\| < \|x-y\|$. )

I am interested in constructing the following "counter-example" to the Banach's fixed point theorem.

Let $K=$ {$ g\in L_1: \|g\|=1, g(\cdot)\ge0 $}. Clearly, $K$ is not a compact and $K$ is not closed.

My A question is: is it possible to construct a [edit] nonexpansive mapping $f: K\to K$ with no fixed point? ( i.e. a mapping $f$ such that [edit] for all $x\neq y\in K$ one has $\|f(x)-f(y)\| < \|x-y\|$. )

m
Source Link
Pietro Majer
  • 60.6k
  • 4
  • 122
  • 269

I am interested in constructing the following "counter-example" to the Banach's fixed point theorem.

Let $K=$ {$ g\in L_1: \|g\|=1, g(\cdot)\ge0 $}. Clearly, $K$ is not a compact and $K$ is not closed not closed.

MyMy A question is: is it possible to construct a [edit] "weak" contraction mapping $f: K\to K$ with no fixed point? (i i.e. a mapping $f$ such that [edit] for all $x,y\in K$$x\neq y\in K$ one has $\|f(x)-f(y)\|\leq \lambda \|x-y\|$ for some$\|f(x)-f(y)\| < \|x-y\|$. $\lambda<1$)

I am interested in constructing the following "counter-example" to the Banach's fixed point theorem.

Let $K=$ {$ g\in L_1: \|g\|=1, g(\cdot)\ge0 $}. Clearly, $K$ is not a compact and $K$ is not closed.

My question is: is it possible to construct a contraction mapping $f: K\to K$ with no fixed point? (i.e. a mapping $f$ such that for all $x,y\in K$ one has $\|f(x)-f(y)\|\leq \lambda \|x-y\|$ for some $\lambda<1$)

I am interested in constructing the following "counter-example" to the Banach's fixed point theorem.

Let $K=$ {$ g\in L_1: \|g\|=1, g(\cdot)\ge0 $}. Clearly, $K$ is not a compact and $K$ is not closed.

My A question is: is it possible to construct a [edit] "weak" contraction mapping $f: K\to K$ with no fixed point? ( i.e. a mapping $f$ such that [edit] for all $x\neq y\in K$ one has $\|f(x)-f(y)\| < \|x-y\|$. )

added 22 characters in body
Source Link
Oleg
  • 931
  • 8
  • 16

I am interested in constructing the following "counter-example" to the Banach's fixed point theorem.

Let $K=$ {$ g\in L_1: \|g\|=1, g(\cdot)\ge0 $}. Clearly, $K$ is not a compact and $K$ is not closed.

My question is: is it possible to construct a contraction mapping $f: K\to K$ with no fixed point? (i.e. a mapping $f$ such that for all $x,y\in K$ one has $\|f(x)-f(y)\|\leq \lambda \|x-y\|$ for some $\lambda<1$)

I am interested in constructing the following "counter-example" to the Banach's fixed point theorem.

Let $K=$ {$ g\in L_1: \|g\|=1, g(\cdot)\ge0 $}. Clearly, $K$ is not a compact.

My question is: is it possible to construct a contraction mapping $f: K\to K$ with no fixed point? (i.e. a mapping $f$ such that for all $x,y\in K$ one has $\|f(x)-f(y)\|\leq \lambda \|x-y\|$ for some $\lambda<1$)

I am interested in constructing the following "counter-example" to the Banach's fixed point theorem.

Let $K=$ {$ g\in L_1: \|g\|=1, g(\cdot)\ge0 $}. Clearly, $K$ is not a compact and $K$ is not closed.

My question is: is it possible to construct a contraction mapping $f: K\to K$ with no fixed point? (i.e. a mapping $f$ such that for all $x,y\in K$ one has $\|f(x)-f(y)\|\leq \lambda \|x-y\|$ for some $\lambda<1$)

Source Link
Oleg
  • 931
  • 8
  • 16
Loading