Classification of second order partial differential equations into elliptic, parabolic and hyperbolic Updated 2025-04-24 +Created 1970-01-01
One major application of this classification is that different boundary conditions are suitable for different types of partial differential equations as explained at: which boundary conditions lead to existence and uniqueness of a second order PDE.
Produced the enriched uranium used for Little Boy, located in the area/predecessor of Oak Ridge National Laboratory.
The group of all transformations that preserve some bilinear form, notable examples:
- orthogonal group preserves the inner product
- unitary group preserves a Hermitian form
- Lorentz group preserves the Minkowski inner product
4 K. Enough for to make "low temperature superconductors" like regular metals superconducting, e.g. the superconducting temperature of aluminum if 1.2 K.
Contrast with liquid nitrogen, which is much cheaper but only goes to 77K.
- newrepublic.com/article/173376/100-political-films-new-republic-list archive.ph/SJCgo The 100 Most Significant Political Films of All Time
HTML snippet:
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}Canonical example: Euclidean space.
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