antipodal points

antipodal points

[an¦tip·əd·əl ′pȯins]
(mathematics)
The points at opposite ends of a diameter of a sphere.
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Then the group G = O(p + 1, q + 1) acts as conformal diffeomorphisms on [S.sup.p] x [S.sup.q], and also on its quotient space X = ([S.sup.p] x [S.sup.q])/[Z.sub.2] by identifying the direct product of antipodal points. By the general theory of conformal groups, one has a natural family of representations [[??].sub.[lambda]] on [C.sup.[infinity]](X) with parameter [lambda] [member of] C [12, Sect.
In Section 3, we build a framework of USTM constellation based on the antipodal points. The optimal packing method of searching the orthogonal unitary matrices over Grassmannian manifold and the corresponding searching algorithm are investigated.
It will mean that, when he includes his previous challenges, Mark will have covered 20,000 miles and passed through two antipodal points on the globe - making it a run around the world.
Another way of assessing the antipodal location of the Earth major landforms severity is the rectilinear correlation r coefficient calculation between absolute heights (depths) of the earth surface within antipodal points. The calculation algorithm is the correlation coefficient for large groups is discussed in detail by the respective papers [8-10].
Definition (14) means that two different spin coherent states overlap unless they are directed into two antipodal points on the sphere [17].
is a continuous function from S [equivalent] [S.sup.2] to [R.sup.2], by the Borsuk-Ulam theorem (see Corollary 9.3 in [18]) there exist two antipodal points of S having the same image.
Proof: We choose a covering [([A.sub.i]).sub.i=0, ..., k+r] of [S.sup.k+r-1] by closed subsets such that no [A.sub.i] contains a pair of antipodal points. Let D := [min.sub.i] dist([A.sub.i], -[A.sub.i]) > 0, 0 < [epsilon] < D and [epsilon]' := D - [epsilon].
Let S = [B.sub.1] [union] [B.sub.2] be a partition of S into two Borel pieces such that no antipodal points of S lie in the same cell of the partition.
Due to symmetry, the ball [rB.sup.d] touches the boundary of Z in at least two antipodal points rw and -rw, w [member of] [S.sup.d-1].
Plane elliptic geometry is closely related to spherical geometry, but it differs in that antipodal points on the sphere are identified.
On the other hand, Borsuk's theorem only requires the mapping f to be continuous on the ball and to fulfill a non-colinearity condition for the function values at all pairs of antipodal points on the boundary of the ball.