Dual Definition and 373 Threads

In geometry, any polyhedron is associated with a second dual figure, where the vertices of one correspond to the faces of the other, and the edges between pairs of vertices of one correspond to the edges between pairs of faces of the other. Such dual figures remain combinatorial or abstract polyhedra, but not all are also geometric polyhedra. Starting with any given polyhedron, the dual of its dual is the original polyhedron.
Duality preserves the symmetries of a polyhedron. Therefore, for many classes of polyhedra defined by their symmetries, the duals belong to a corresponding symmetry class. For example, the regular polyhedra – the (convex) Platonic solids and (star) Kepler–Poinsot polyhedra – form dual pairs, where the regular tetrahedron is self-dual. The dual of an isogonal polyhedron (one in which any two vertices are equivalent) is an isohedral polyhedron (one in which any two faces are equivalent), and vice-versa. The dual of an isotoxal polyhedron (one in which any two edges are equivalent) is also an isotoxal polyhedron.
Duality is closely related to reciprocity or polarity, a geometric transformation that, when applied to a convex polyhedron, realizes the dual polyhedron as another convex polyhedron.

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  1. G

    I How does one find the dual of a matrix?

    How does one find the dual of a matrix? Thanks.
  2. D

    ESA's Dual Stage 4 Grid Ion propulsion

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  3. D

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  4. J

    I Observer effect in the Dual Slit experiment

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  5. M

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  6. P

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  7. J

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  8. E

    I How can the dual tensors derivation be achieved using rotation matrices?

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  9. abhinavabhatt

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  10. M

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  11. M

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  12. S

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  13. M

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  14. M

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  16. steve1763

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  17. A

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  18. Kaguro

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  19. Buckethead

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  20. dontknow

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  21. Y

    Programs Is a Dual Master's in Electrical and Systems Engineering Worth It?

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  22. K

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  23. E

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  24. patric44

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  25. P

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  26. P

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  28. J

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  29. G

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  30. S

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  31. P

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  32. G

    A How to prove this property of the Dual Strength Field Tensor?

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  33. pixel

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  34. K

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  35. J

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  36. Math Amateur

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  37. Math Amateur

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  38. Math Amateur

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  39. George Keeling

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  40. Math Amateur

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  41. R

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  42. E

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  43. I

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  44. A

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  45. P

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  47. T

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  48. Gene Naden

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  49. L

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  50. L

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