Blar i UiS Brage på forfatter "Hervik, Sigbjørn"
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A spacetime not characterized by its invariants is of aligned type II
Hervik, Sigbjørn (Journal article; Peer reviewed, 2011)By using invariant theory we show that a (higher-dimensional) Lorentzian metric that is not characterised by its invariants must be of aligned type II; i.e., there exists a frame such that all the curvature tensors ... -
All metrics have curvature tensors characterised by its invariants as a limit: the ϵ-property
Hervik, Sigbjørn (Journal article; Peer reviewed, 2011)We prove a generalisation of the ϵ-property, namely that for any dimension and signature, a metric which is not characterised by its polynomial scalar curvature invariants, there is a frame such that the components of the ... -
Curvature operators and scalar curvature invariants
Hervik, Sigbjørn; Coley, Alan (Journal article; Peer reviewed, 2010)We continue the study of the question of when a pseudo-Riemannain manifold can be locally characterised by its scalar polynomial curvature invariants (constructed from the Riemann tensor and its covariant deriva- tives). ... -
Discriminating the Weyl type in higher dimensions using scalar curvature invariants
Hervik, Sigbjørn; Coley, Alan (Journal article; Peer reviewed, 2011)We consider higher dimensional Lorentzian spacetimes which are currently of interest in theoretical physics. It is possible to algebraically classify any tensor in a Lorentzian spacetime of arbitrary dimensions using ... -
Dybdelæring i matematikk
Serigstad, Adrian (Master thesis, 2023)This study examines deep learning in mathematics and investigates whether a focus on deep learning can lead to deep understanding of a mathematical topic. Deep learning proves to be a diverse concept with various interpretations ... -
Dybdelæring og tverrfaglighet
Østebø, Marlene Seljeskog; Urianstad, Simen Bugge (Master thesis, 2023)Da ny læreplan av 2020 ble introdusert, var det spesielt et begrep som stod i fokus - dybdelæring. Hvor tidligere læreplan ønsket at elevene skulle kunne utføre oppgaver gjennom en instrumentell forståelse, skulle elevene ... -
Higher dimensional bivectors and classification of the Weyl operator
Hervik, Sigbjørn; Coley, Alan (Journal article; Peer reviewed, 2010)We develop the bivector formalism in higher dimensional Lorentzian spacetimes. We define the Weyl bivector operator in a manner consis- tent with its boost-weight decomposition. We then algebraically classify the Weyl ... -
Inflation with stable anisotropic hair
Hervik, Sigbjørn; Mota, David F.; Thorsrud, Mikjel (Journal article; Peer reviewed, 2011)Recently an inflationary model with a vector field coupled to the inflaton was proposed and the phenomenology studied for the Bianchi type I spacetime. It was found that the model demonstrates a counter-example to the ... -
Left-Invariant Pseudo-Riemannian Metrics on Lie Groups
Markestad, Styrbjørn Juhl (Masteroppgave/UIS-TN-IMF/2020;, Master thesis, 2020)n differential geometry and mathematical physics, there is interest in left-invariant pseudo-Riemannian metrics on Lie groups. We learn and review Lie theory, representation theory, geometric invariant theory, and differential ... -
A mathematical approach to Wick rotations
Helleland, Christer (PhD thesis UiS;536, Doctoral thesis, 2020-09)In this thesis we define Wick-rotations mathematically using pseudo-Riemannian geometry, and relate Wick-rotations to real geometric invariant theory (GIT). We discover some new results concerning the existence of Wick ... -
Nil-Killing vector fields and Kundt structures
Aadne, Matthew Terje (PhD thesis UiS;529, Doctoral thesis, 2020-06)This thesis is based on three papers, for which two have been submitted for publication and one is published. A chapter presenting relevant background material is included giving convenient access to preliminary foreknowledge ... -
Note on the invariant classification of vacuum type D spacetimes
Coley, Alan; Hervik, Sigbjørn (Journal article; Peer reviewed, 2009-12)We illustrate the fact that the class of vacuum type D spacetimes which are I-non-degenerate are invariantly classified by their scalar polynomial curvature invariants. -
On the algebraic classification of pseudo-Riemannian spaces
Hervik, Sigbjørn; Coley, Alan (Journal article; Peer reviewed, 2011-12)We consider arbitrary-dimensional pseudo-Riemannian spaces of signature (k, k + m). We introduce a boost-weight decomposition and define a number of algebraic properties (e.g. the Si- and N-properties) and present a ... -
On Universal Black Holes
Hervik, Sigbjørn; Ortaggio, Marcello (Peer reviewed; Journal article, 2020)Recent results on universal black holes in d dimensions are summarized. These are static metrics with an isotropy-irreducible homogeneous base space which can be consistently employed to construct solutions to virtually ... -
Open Middle Math og dybdelæring i Matematikk
Nesheim, Sigrunn Westersjø (Master thesis, 2022)Denne oppgaven trekker frem undervisningskonseptet Open Middle Math (Kaplinsky, Open Middle Math, 2020) og drøfter om dette konseptet bidrar til dybdelæring i matematikk. For å besvare dette spørsmålet er det gjennomført ... -
"Open Middle Math" og dets bidrag til dybdelæring i matematikk
Seland, Didrik (Master thesis, 2022)Dette prosjektet baserer seg på Robert Kaplinskys (Kaplinsky, 2020) teori om «Open Middle Math», og har som mål å undersøke om undervisning med dette kan bidra til dybdelæring hos elever. I forbindelse med prosjektet ble ... -
«Open Middle Math» og dets bidrag til undervisning i matematikk
Mølstre, Monica Emilie (Master thesis, 2021)I denne masteroppgaven er det foretatt innhenting av datamateriale gjennom elevers oppgaveløsning i rammeverket «Open Middle Math». Målet ved observasjon og utprøving av oppgavetypen har vært å se om det kan være et godt ... -
«Open Middle Math», dybdelæring & positive holdninger i matematikk
Ramstad, Sunniva Fosnes (Masteroppgave/UIS-HF-IMF/2020;, Master thesis, 2019-07)Som både lektorstudent og deltidsarbeidene i videregående skole er det mye fokus på hvordan lærere skal forberede seg i møte med fagfornyelsen. Dybdelæring er et sentralt begrep i fagfornyelsen. Motivasjonen for denne ... -
Pseudo-Riemannian VSI spaces
Hervik, Sigbjørn; Coley, Alan (Journal article; Peer reviewed, 2011)In this paper we consider pseudo-Riemannian spaces of arbitrary sig- nature for which all of their polynomial curvature invariants vanish (VSI spaces). We discuss an algebraic classification of pseudo-Riemannian spaces ... -
Pseudo-Riemannian VSI spaces II
Hervik, Sigbjørn (Journal article; Peer reviewed, 2012)In this paper we consider pseudo-Riemannian spaces of arbitrary signature for which all of the polynomial curvature invariants vanish (VSI spaces). Using an algebraic classification of pseudo-Riemannian spaces in terms of ...