"1657;1664" . . . "Ricci identities in higher dimensions"@en . . "higher dimensional gravixy"@en . . . "RIV/67985840:_____/07:00080186!RIV07-AV0-67985840" . "We explore connections between geometrical properties of null congruences and the algebraic structure of the Weyl tensor in n > 4 spacetime dimensions. First, we present the full set of Ricci identities on a suitable %22null%22 frame, thus completing the extension of the Newman-Penrose formalism to higher dimensions. Then we specialize to geodetic null congruences and study specific consequences of the Sachs equations. These imply, for example, that Kundt spacetimes are type II or more special (like for n = 4) and that for odd n a twisting geodetic WAND must also be shearing (in contrast to the case n = 4)." . "Classical and Quantum Gravity" . "6" . "Pravda, Vojt\u011Bch" . . "We explore connections between geometrical properties of null congruences and the algebraic structure of the Weyl tensor in n > 4 spacetime dimensions. First, we present the full set of Ricci identities on a suitable %22null%22 frame, thus completing the extension of the Newman-Penrose formalism to higher dimensions. Then we specialize to geodetic null congruences and study specific consequences of the Sachs equations. These imply, for example, that Kundt spacetimes are type II or more special (like for n = 4) and that for odd n a twisting geodetic WAND must also be shearing (in contrast to the case n = 4)."@en . "2"^^ . . "3"^^ . "Ricci identities in higher dimensions" . "[84ADC8D34E8A]" . . "Ricci identities in higher dimensions"@en . "447819" . . "RIV/67985840:_____/07:00080186" . "Ricciho identity ve vy\u0161\u0161\u00EDch dimenz\u00EDch"@cs . . . . "V prostoro\u010Dasech o dimenzi n>4 zkoum\u00E1me souvislosti mezi geometrick\u00FDmi vlastnostmi nulov\u00FDch kongruenc\u00ED a algebraickou strukturou Weylova tenzoru. Nejprve ve vhodn\u00E9 b\u00E1zi uv\u00E1d\u00EDme \u00FAplnou soustavu Ricciho identit a zavr\u0161ujeme tak zobecn\u011Bn\u00ED Newmanova-Penroesova formalismu do vy\u0161\u0161\u00EDch dimenz\u00ED. Pot\u00E9 se specializujeme na nulov\u00E9 geodetick\u00E9 kongruence a studujeme d\u016Fsledky Sachsov\u00FDch rovnic. Tyto rovnice nap\u0159\u00EDklad implikuj\u00ED, \u017Ee Kundtovy prostoro\u010Dasy jsou typu II a \u017Ee v lich\u00FDch dimenz\u00EDch maj\u00ED na rozd\u00EDl od p\u0159\u00EDpadu n=4 twistuj\u00EDc\u00ED WANDy nenulov\u00FD shear."@cs . "Ricci identities in higher dimensions" . "Ricciho identity ve vy\u0161\u0161\u00EDch dimenz\u00EDch"@cs . "GB - Spojen\u00E9 kr\u00E1lovstv\u00ED Velk\u00E9 Brit\u00E1nie a Severn\u00EDho Irska" . . "0264-9381" . "8"^^ . . "Ortaggio, M." . "P(KJB100190702), Z(AV0Z10190503)" . "24" . "Pravdov\u00E1, Alena" . . .