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YCor
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Density of Continuous Functionscontinuous functions to interior in set of all continuous functions

Let $M$ be an $m$ dimensional-dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.


 

Intuitively isit seems that every continuous function $f:M\rightarrow N$ should be able tocan be approximated by continuous functions of the form $g:M\rightarrow\operatorname{int}(N)$; where $N=\operatorname{int}(N)\cup \partial N$$\operatorname{int}(N)=N- \partial N$, $\partial N$ denotesdenoting the boundary of $N$ and $\operatorname{int}(N)$ the $n$-dimensional manifold defined by removing $N's$ boundary points but. But is this formally true? I.e., is it true that

$$ \overline{C(M,\operatorname{int}(N)} = C(M,N)? $$$$ \overline{C(M,\operatorname{int}(N))} = C(M,N)? $$


Prototype construction: Let $N=[0,b)$ then any function $f$ can be approximated by: $$ f_n= \min\left(\frac1{n},f\right) , $$ of course, these are continuous but not smooth *(since we don't need smoothness this is a non-issuenot an issue). I expect this type of construction should generalize..can be generalized.

Density of Continuous Functions to interior in set of all continuous functions

Let $M$ be an $m$ dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.


 

Intuitively is seems that every continuous function $f:M\rightarrow N$ should be able to be approximated by continuous functions of the form $g:M\rightarrow\operatorname{int}(N)$; where $N=\operatorname{int}(N)\cup \partial N$, $\partial N$ denotes the boundary of $N$ and $\operatorname{int}(N)$ the $n$-dimensional manifold defined by removing $N's$ boundary points but is this formally true? I.e. is it true that

$$ \overline{C(M,\operatorname{int}(N)} = C(M,N)? $$


Prototype construction: Let $N=[0,b)$ then any function $f$ can be approximated by: $$ f_n= \min\left(\frac1{n},f\right) , $$ of course, these are continuous but not smooth *(since we don't need smoothness this is a non-issue). I expect this type of construction should generalize...

Density of continuous functions to interior in set of all continuous functions

Let $M$ be an $m$-dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.

Intuitively it seems that every continuous function $f:M\rightarrow N$ can be approximated by continuous functions of the form $g:M\rightarrow\operatorname{int}(N)$; where $\operatorname{int}(N)=N- \partial N$, $\partial N$ denoting the boundary of $N$. But is this formally true? I.e., is it true that

$$ \overline{C(M,\operatorname{int}(N))} = C(M,N)? $$


Prototype construction: Let $N=[0,b)$ then any function $f$ can be approximated by: $$ f_n= \min\left(\frac1{n},f\right) , $$ of course, these are continuous but not smooth (since we don't need smoothness this is not an issue). I expect this type of construction can be generalized.

Minor Math Jaxing cares (`int -> \operatorname{int}`, `min -> \min`, bracket scaling) + a typo correction + minor grammar improvements
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Let $M$ be an $m$ dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.


Intuitively is seems that every continuous function $f:M\rightarrow N$ should be able to be approximated by continuous functions of the form $g:M\rightarrow int(N)$$g:M\rightarrow\operatorname{int}(N)$; where $N=int(N)\cup \partial N$$N=\operatorname{int}(N)\cup \partial N$, $\partial N$ denotes the boundary of $N$ and $int(N)$$\operatorname{int}(N)$ the $n$-dimensional manifold defined by removing $N's$ boundary points but is this formally true? ie: I.e. is: it true that

$$ \overline{C(M,int(N)} = C(M,N)? $$$$ \overline{C(M,\operatorname{int}(N)} = C(M,N)? $$


Prototype construction: Let $N=[0,b)$ then any function $f$ can be approximated by: $$ f_n= min(\frac1{n},f) , $$$$ f_n= \min\left(\frac1{n},f\right) , $$ of course, these are continuous but not smooth *(since we don't need smoothness this is a non-issue). I expect this type of contstructionconstruction should generalize...

Let $M$ be an $m$ dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.


Intuitively is seems that every continuous function $f:M\rightarrow N$ should be able to be approximated by continuous functions of the form $g:M\rightarrow int(N)$; where $N=int(N)\cup \partial N$, $\partial N$ denotes the boundary of $N$ and $int(N)$ the $n$-dimensional manifold defined by removing $N's$ boundary points but is this formally true? ie: is:

$$ \overline{C(M,int(N)} = C(M,N)? $$


Prototype construction: Let $N=[0,b)$ then any function $f$ can be approximated by: $$ f_n= min(\frac1{n},f) , $$ of course, these are continuous but not smooth *(since we don't need smoothness this is a non-issue). I expect this type of contstruction should generalize...

Let $M$ be an $m$ dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.


Intuitively is seems that every continuous function $f:M\rightarrow N$ should be able to be approximated by continuous functions of the form $g:M\rightarrow\operatorname{int}(N)$; where $N=\operatorname{int}(N)\cup \partial N$, $\partial N$ denotes the boundary of $N$ and $\operatorname{int}(N)$ the $n$-dimensional manifold defined by removing $N's$ boundary points but is this formally true? I.e. is it true that

$$ \overline{C(M,\operatorname{int}(N)} = C(M,N)? $$


Prototype construction: Let $N=[0,b)$ then any function $f$ can be approximated by: $$ f_n= \min\left(\frac1{n},f\right) , $$ of course, these are continuous but not smooth *(since we don't need smoothness this is a non-issue). I expect this type of construction should generalize...

added 237 characters in body
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ABIM
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Let $M$ be an $m$ dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.


Intuitively is seems that every continuous function $f:M\rightarrow N$ should be able to be approximated by continuous functions of the form $g:M\rightarrow int(N)$; where $N=int(N)\cup \partial N$, $\partial N$ denotes the boundary of $N$ and $int(N)$ the $n$-dimensional manifold defined by removing $N's$ boundary points but is this formally true? ie: is:

$$ \overline{C(M,int(N)} = C(M,N)? $$


Prototype construction: Let $N=[0,b)$ then any function $f$ can be approximated by: $$ f_n= min(\frac1{n},f) , $$ of course, these are continuous but not smooth *(since we don't need smoothness this is a non-issue). I expect this type of contstruction should generalize...

Let $M$ be an $m$ dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.


Intuitively is seems that every continuous function $f:M\rightarrow N$ should be able to be approximated by continuous functions of the form $g:M\rightarrow int(N)$; where $N=int(N)\cup \partial N$, $\partial N$ denotes the boundary of $N$ and $int(N)$ the $n$-dimensional manifold defined by removing $N's$ boundary points but is this formally true? ie: is:

$$ \overline{C(M,int(N)} = C(M,N)? $$

Let $M$ be an $m$ dimensional manifold and $N$ be an $n$-dimensional manifold *with boundary*. Suppose also that the topology on $N$ can be described by a metric. Thus, the set $C(M,N)$ can be endowed with the topology of uniform convergence on compacta.


Intuitively is seems that every continuous function $f:M\rightarrow N$ should be able to be approximated by continuous functions of the form $g:M\rightarrow int(N)$; where $N=int(N)\cup \partial N$, $\partial N$ denotes the boundary of $N$ and $int(N)$ the $n$-dimensional manifold defined by removing $N's$ boundary points but is this formally true? ie: is:

$$ \overline{C(M,int(N)} = C(M,N)? $$


Prototype construction: Let $N=[0,b)$ then any function $f$ can be approximated by: $$ f_n= min(\frac1{n},f) , $$ of course, these are continuous but not smooth *(since we don't need smoothness this is a non-issue). I expect this type of contstruction should generalize...

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ABIM
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