| 21. |
- Andreasson, Håkan, 1966, et al.
(författare)
-
Existence of axially symmetric static solutions of the Einstein-Vlasov system
- 2011
-
Ingår i: Commun. Math. Phys.. - : Springer Science and Business Media LLC. - 0010-3616 .- 1432-0916. ; 308, s. 23-47
-
Tidskriftsartikel (refereegranskat)abstract
- We prove the existence of static, asymptotically flat non-vacuum spacetimes with axial symmetry where the matter is modeled as a collisionless gas. The axially symmetric solutions of the resulting Einstein-Vlasov system are obtained via the implicit function theorem by perturbing off a suitable spherically symmetric steady state of the Vlasov-Poisson system.
|
|
| 22. |
|
|
| 23. |
- Andreasson, Håkan, 1966
(författare)
-
Existence of Steady States of the Massless Einstein-Vlasov System Surrounding a Schwarzschild Black Hole
- 2021
-
Ingår i: Annales Henri Poincare. - : Springer Science and Business Media LLC. - 1424-0637 .- 1424-0661. ; 22
-
Tidskriftsartikel (refereegranskat)abstract
- We show that there exist steady states of the spherically symmetric massless Einstein-Vlasov system which surround a Schwarzschild black hole. The steady states are (thick) shells with finite mass and compact support. Furthermore we prove that an arbitrary number of shells, necessarily well separated, can surround the black hole. To our knowledge this is the first result of static self-gravitating solutions to any massless Einstein-matter system which surround a black hole. We also include a numerical investigation about the properties of the shells.
|
|
| 24. |
- Andreasson, Håkan, 1966, et al.
(författare)
-
Formation of trapped surfaces for the spherically symmetric Einstein-Vlasov system
- 2010
-
Ingår i: Journal of Hyperbolic Differential Equations. - Göteborg : Chalmers University of Technology. - 0219-8916. ; 7:4, s. 707-731
-
Tidskriftsartikel (refereegranskat)abstract
- We consider the spherically symmetric, asymptotically flat, non-vacuum Einstein equations, using as matter model a collisionless gas as described by the Vlasov equation. We find explicit conditions on the initial data which guarantee the formation of a trapped surface in the evolution which in particular implies that weak cosmic censorship holds for these data. We also analyze the evolution of solutions after a trapped surface has formed and we show that the event horizon is future complete. Furthermore we find that the apparent horizon and the event horizon do not coincide. This behavior is analogous to what is found in certain Vaidya spacetimes. The analysis is carried out in Eddington-Finkelstein coordinates.
|
|
| 25. |
|
|
| 26. |
- Andreasson, Håkan, 1966, et al.
(författare)
-
Global existence for the spherically symmetric Einstein-Vlasov system with outgoing matter
- 2008
-
Ingår i: Communications in Partial Differential Equations. - : Informa UK Limited. - 0360-5302 .- 1532-4133. ; 33:4, s. 656-668
-
Tidskriftsartikel (refereegranskat)abstract
- We prove a new global existence result for the asymptotically flat, spherically symmetric Einstein-Vlasov system which describes in the framework of general relativity an ensemble of particles which interact by gravity. The data are such that initially all the particles are moving radially outward and that this property can be bootstrapped. The resulting non-vacuum spacetime is future geodesically complete.
|
|
| 27. |
|
|
| 28. |
|
|
| 29. |
- Andreasson, Håkan, 1966, et al.
(författare)
-
Gravitational collapse and the formation of black holes for the spherically symmetric Einstein-Vlasov system.
- 2010
-
Ingår i: Quarterly of Applied Mathematics. - 1552-4485. ; 68, s. 17-42
-
Tidskriftsartikel (refereegranskat)abstract
- We review results on the spherically symmetric, asymptotically flat Einstein-Vlasov system. We focus on a recent result where we found explicit conditions on the initial data which guarantee the formation of a black hole in the evolution. Among these data there are data such that the corresponding solutions exist globally in Schwarzschild coordinates. We put these results into a more general context, and we include arguments which show that the spacetimes we obtain satisfy the weak cosmic censorship conjecture and contain a black hole in the sense of suitable mathematical definitions of these concepts which are available in the literature.
|
|
| 30. |
- Andreasson, Håkan, et al.
(författare)
-
Histopathological classification of pseudomyxoma peritonei and the prognostic importance of PINCH protein
- 2012
-
Ingår i: Anticancer Research. - : International Institute of Anticancer Research (IIAR). - 0250-7005 .- 1791-7530. ; 32:4, s. 1443-1448
-
Tidskriftsartikel (refereegranskat)abstract
- AIM: The aims of this study were i) to assess a new and more detailed histopathological classification and to analyze concordance between pathologists in the histopathological classification of pseudomyxoma peritonei (PMP); ii) to analyze the expression in the stroma of the particularly interesting new cysteine-histidine (PINCH) protein and its prognostic importance in PMP.MATERIALS AND METHODS: Surgical specimens from 81 patients, classified according to the Ronnett et al histopathological classification were compared to a new system with four groups ranging from indolent to aggressive growth patterns. PINCH protein expression was analyzed and was related to clinical variables.RESULTS: The new four-group classification provided better prognostic information than the classification according to Ronnett et al. (p=0.04). Expression of the PINCH protein in the stroma was found in 83% of the cases and was associated with high tumor burden (p=0.002) and a poor prognosis (p=0.04).CONCLUSION: The proposed new PMP classification system may provide additional prognostic information. PINCH protein is expressed in PMP and has prognostic information.
|
|
