Results 41 to 50 of about 5,017 (222)
ON THE DEFINITION OF MATTER COLLINEATIONS [PDF]
Modern Physics Letters A, 2009 It is shown that when the stress–energy tensor of a spacetime is diagonal and is written in the mixed form, its collineations admit infinite dimensional Lie algebras except possibly in the case when the tensor depends on all the spacetime coordinates. The result can be extended for more general second rank tensors.
Asghar Qadir, Khalid Saifullah
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symmetries of the Ricci tensor of static space times with maximal symmetric transverse spaces
, 2006 Static space times with maximal symmetric transverse spaces are classified according to their Ricci collineations. These are investigated for non-degenerate Ricci tensor ($det.(R_{\alpha}) \neq 0$).
A.Z. Petro +4 more
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Collineation as a mode of motion
, 1892 Perhaps the most important difference between the old and the new geometry lies in the extended use made during the present century of geometric transformations, f The change which has come about in this direction is due in part to the influence of ...
M. Bôcher
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Treacher Collins syndrome [PDF]
Human Molecular Genetics, 1995 Treacher Collins syndrome is an autosomal dominant disorder of craniofacial development, the features of which include conductive hearing loss and cleft palate. In the absence of a candidate gene, a positional cloning approach has been used to isolate the mutated gene which maps to chromosome 5q31.3-32.
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On the equivalence of linear sets
, 2015 Let $L$ be a linear set of pseudoregulus type in a line $\ell$ in $\Sigma^*=\mathrm{PG}(t-1,q^t)$, $t=5$ or $t>6$. We provide examples of $q$-order canonical subgeometries $\Sigma_1,\, \Sigma_2 \subset \Sigma^*$ such that there is a $(t-3)$-space $\Gamma
Csajbók, Bence, Zanella, Corrado
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Edinburgh Mathematical Notes, 1960 If in a complex projective plane a point P, with coordinate vector x, corresponds to a point p*, with coordinate vector x*, under a non-singular collineation, thenx* = Axwhere A is a non-singular 3×3 matrix, the coordinates and the elements of A being complex numbers.
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Complete collineations revisited [PDF]
Mathematische Annalen, 1999 The space of complete collineations is a compactification of the space of matrices of fixed dimension and rank, whose boundary is a divisor with normal crossings. It was introduced in the 19th century and has been used to solve many enumerative problems.
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On Quasi‐Hermitian Varieties in Even Characteristic and Related Orthogonal Arrays
Journal of Combinatorial Designs, Volume 33, Issue 3, Page 109-122, March 2025.ABSTRACT In this article, we study the BM quasi‐Hermitian varieties, laying in the three‐dimensional Desarguesian projective space of even order. After a brief investigation of their combinatorial properties, we first show that all of these varieties are projectively equivalent, exhibiting a behavior which is strikingly different from what happens in ...
Angela Aguglia +3 more
wiley +1 more source
Canadian Geographies / Géographies canadiennes, Volume 69, Issue 1, Spring / printemps 2025.Abstract North America is characterized by an expansive continental plain that has been described as platter‐flat. Yet this central continental plain includes isolated uplands that some people call mountains. The hill‐mountain muddle is a classic problem of geomorphology, arising from the challenge of discriminating continuous, attached forms.
Murray M. Humphries +3 more
wiley +1 more source
Intensity gradient based edge detection for pixelated communication systems
The Journal of Engineering, Volume 2019, Issue 12, Page 8463-8470, December 2019., 2019 Pixelated optical communication systems transmit data using a series of encoded pixelated images. The decoding of these pixelated images is important for reliable data communication. This study proposes a novel intensity gradient‐based edge detection (IGED) method for the received pixelated images.
Md Ahasan Kabir +1 more
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