The Examples of Generators of 2-cob Cobordisms in Semi-Riemannian Space R(3,1)

Öz

In their book published in 1996, Duggal and Bejancu demonstrated the existence of a lightlike (null) subspace in a semi-Riemannian manifold and filled an important gap needed for the geometry of submanifolds. In addition to birational invariants such as uniruledness and kodaira dimensions for Semi-Riemannian manifolds, in this study, by emphasizing the k (U) values which are the numbers of maximum linearly independent lightlike vectors, that are a birational invariance, the examples of generators of 2- Cob cobordisms are given in Semi-Riemannian Space R(3,1). Their codaira dimensions and k (U) invariants of these examples has been expressed.

Anahtar Kelimeler

• Cobordism
• Birationel invariant
• Semi-Riemannian manifold
• Kodaira dimension
• Ruled variety

R(3,1) Semi-Riemannian Uzayda 2-Cob Üreteç Kobordizm Örnekleri

Öz

Duggal ve Bejancu 1996 da yayınladıkları kitapta bir semi-Riemannian manifoldda lightlike (null) alt uzayın varlığını gösterdiler ve alt manifoldların geometrisi için ihtiyaç duyulan önemli bir boşluğu doldurdular. Semi-Riemannian manifoldlar için unireglelik, kodaira boyutu gibi birasyonel invaryantların yanında maximum lineer bağımsız lightlike vektörlerin sayıları olan k(U) değerlerinin de bir birasyonel invaryant olduğu vurgıulanarak R31 Semi-Riemannian Uzayda 2-Cob Üreteç kobordizmlere örnekler verilmiş, bunların kodaira boyutları ve k(U) invaryantları ifade edilmiştir.

Anahtar Kelimeler

• Kobordizm
• Birasyonel invaryant
• Semi-Riemannian manifold
• Kodaira boyutu
• Regle yapı

Kaynakça

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