Question to the Lax-Oleinik formula in Evans PDE












1














On p. 146 in Evans' book Partial Differential equations (AMS, 1998), it is written:




Now for each $ x ∈ mathbb{R}$ and $t > 0$, define the
point $y(x,t)$ to equal the smallest of those points $y$ giving the minimum of $t L(frac{x−y}{t})+h(y)$.
Then the mapping $x → y(x,t)$ is nondecreasing and is thus continuous for all but at most countably many $x$. At a point $x$ of continuity of $y(·,t)$, $y(x,t)$ is the unique value of $y$ yielding the minimum.




I am trying to see why at a point $x$ of continuity of $y(·,t)$, $y(x,t)$ is the unique value of $y$ yielding the minimum.
Can someone help me with that?










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    1














    On p. 146 in Evans' book Partial Differential equations (AMS, 1998), it is written:




    Now for each $ x ∈ mathbb{R}$ and $t > 0$, define the
    point $y(x,t)$ to equal the smallest of those points $y$ giving the minimum of $t L(frac{x−y}{t})+h(y)$.
    Then the mapping $x → y(x,t)$ is nondecreasing and is thus continuous for all but at most countably many $x$. At a point $x$ of continuity of $y(·,t)$, $y(x,t)$ is the unique value of $y$ yielding the minimum.




    I am trying to see why at a point $x$ of continuity of $y(·,t)$, $y(x,t)$ is the unique value of $y$ yielding the minimum.
    Can someone help me with that?










    share|cite|improve this question



























      1












      1








      1







      On p. 146 in Evans' book Partial Differential equations (AMS, 1998), it is written:




      Now for each $ x ∈ mathbb{R}$ and $t > 0$, define the
      point $y(x,t)$ to equal the smallest of those points $y$ giving the minimum of $t L(frac{x−y}{t})+h(y)$.
      Then the mapping $x → y(x,t)$ is nondecreasing and is thus continuous for all but at most countably many $x$. At a point $x$ of continuity of $y(·,t)$, $y(x,t)$ is the unique value of $y$ yielding the minimum.




      I am trying to see why at a point $x$ of continuity of $y(·,t)$, $y(x,t)$ is the unique value of $y$ yielding the minimum.
      Can someone help me with that?










      share|cite|improve this question















      On p. 146 in Evans' book Partial Differential equations (AMS, 1998), it is written:




      Now for each $ x ∈ mathbb{R}$ and $t > 0$, define the
      point $y(x,t)$ to equal the smallest of those points $y$ giving the minimum of $t L(frac{x−y}{t})+h(y)$.
      Then the mapping $x → y(x,t)$ is nondecreasing and is thus continuous for all but at most countably many $x$. At a point $x$ of continuity of $y(·,t)$, $y(x,t)$ is the unique value of $y$ yielding the minimum.




      I am trying to see why at a point $x$ of continuity of $y(·,t)$, $y(x,t)$ is the unique value of $y$ yielding the minimum.
      Can someone help me with that?







      pde optimization






      share|cite|improve this question















      share|cite|improve this question













      share|cite|improve this question




      share|cite|improve this question








      edited Nov 23 '18 at 17:39









      Harry49

      6,00121031




      6,00121031










      asked Nov 21 '18 at 23:22









      Infinite_28Infinite_28

      1978




      1978






















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