Recent content by Dr_Noface

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    Graduate The Boundary of a Countable Union of Almost Disjoint Cubes

    My apologies, yes. If two cubes are almost disjoint then only their boundaries intersect.
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    Graduate The Boundary of a Countable Union of Almost Disjoint Cubes

    Let E be a subset of R2 that is non-empty, compact, and connected. Suppose furthermore that E is the union of a countably infinite number of almost disjoint closed cubes {Ri} with non-zero volume. Is there anything interesting about this set, particularly its boundary? Can it have infinite...
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    Graduate Puzzled by A coupled system of PDEs

    Sorry about the format, bit I have no knowledge of LateX. A,B - are real constants U=(Ux,Uy,Uz) I have a system of three coupled linear second order differential equations (di)^2(Ui) +A*Laplacian(Ui)+ B*di[Divergence(U)] Note: The first term is not a sum. 0<z<H, while x & y can...