Sökning: "gravitational collapse"

Visar resultat 1 - 5 av 18 avhandlingar innehållade orden gravitational collapse.

  1. 1. Gravitational collapse in bimetric gravity

    Författare :Marcus Högås; Edvard Mörtsell; Tomi Koivisto; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Bimetric gravity; bigravity; modified gravity; gravitational collapse; Bimetrisk gravitation; modifierad gravitation; gravitationskollaps; Theoretical Physics; teoretisk fysik;

    Sammanfattning : Einstein’s theory of general relativity has been the prevailing theory of classical gravity for over a century. Its observational consistency is unparalleled. There are however a few (arguably) serious short-comings. LÄS MER

  2. 2. Supernovae seen through gravitational telescopes

    Författare :Tanja Petrushevska; Rahman Amanullah; Ariel Goobar; Saurabh Jha; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; supernovae; strong gravitational lensing; star formation history; supernova rates; supernovor Gravitationslins; Physics; fysik;

    Sammanfattning : Galaxies, and clusters of galaxies, can act as gravitational lenses and magnify the light of objects behind them. The effect enables observations of very distant supernovae, that otherwise would be too faint to be detected by existing telescopes, and allows studies of the frequency and properties of these rare phenomena when the universe was young. LÄS MER

  3. 3. Fluid dynamic principles for analysis of intracranial pressure control : application towards space medicine and hydrocephalus

    Författare :Petter Holmlund; Anders Eklund; Sara Qvarlander; Jan Malm; Marek Czosnyka; Umeå universitet; []
    Nyckelord :MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Intracranial pressure; posture; cerebrospinal fluid; microgravity; venous collapse; internal jugular vein; fluid dynamics; venous pressure; spaceflight-associated neuro-ocular syndrome; hydrocephalus; mathematical modeling; ultrasound; magnetic resonance imaging;

    Sammanfattning : Intracranial pressure (ICP) is an important component of the fluid dynamic environment of the brain and plays a central role with regards to the maintenance of normal cerebral blood flow and neuronal function. However, many regulatory mechanisms controlling the ICP are still poorly understood. LÄS MER

  4. 4. Gravitational lensing as a probe of the first stars and galaxies

    Författare :Claes-Erik Rydberg; Erik Zackrisson; Lise Christensen; Stockholms universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; stars: Population III; first stars; Galaxies: high-redshift; Galaxies: Population III; dark ages; reionization; techniques: photometric; Astronomy; astronomi;

    Sammanfattning : This thesis investigates the potential for detection and identification of primordial stars, galaxies, and supernovae at high redshift.Simulations indicate that the first Population III stars should appear in minihalos of mass M = 105-106 Msol at z ≈ 10-30. LÄS MER

  5. 5. Safe Robotic Manipulation to Extract Objects from Piles : From 3D Perception to Object Selection

    Författare :Rasoul Mojtahedzadeh; Achim J. Lilienthal; Todor Stoyanov; Abdelbaki Bouguerra; Erik Schaffernicht; Patric Jensfelt; Örebro universitet; []
    Nyckelord :NATURAL SCIENCES; NATURVETENSKAP; NATURVETENSKAP; NATURAL SCIENCES; Object Selection; Object Pose Refinement; Gravitational Support Relation; Inter-penetration Resolving; 3D Ranging Sensor Evaluation; Datavetenskap; Computer Science;

    Sammanfattning : This thesis is concerned with the task of autonomous selection of objects to remove (unload) them from a pile in robotic manipulation systems. Applications such as the automation of logistics processes and service robots require an ability to autonomously manipulate objects in the environment. LÄS MER