Complex Systems Modeling (CoSMo)

Group leader: Sigrunn Sørbye

The research group is devoted to mathematical and statistical modeling of complex physical, biological and socio-economic systems:

• climate dynamics
• stochastic and dynamical models
• epidemiology and ecology
• non-linear optics and laser physics

The CoSMo group is doing research and is advising master and PhD students within all of these problem domains.

Recent publications:

• Mansuripur M, Jakobsen P, Electromagnetic radiation and the self-torque of an oscillating magnetic dipole, Proc. SOIE 11462, Plasmonics, Design, Materials, Fabrications, Characterizations, and Applications XVIII, (2020). https://doi.org/10.1117/12.2569137
  
• Mansuripur M, Jakobsen P, Electromagnetic radiation and the self-field of a spherical dipole oscillator, American Journal of Physics 88,693,(2020). https://doi.org/10.1119/10.0001348
• Hofstrand A., Jakobsen P. and Moloney J. V., Bidirectional shooting method for extreme nonlinear optics, Phys. Rev. A 100.053818.(2019), https://doi.org/10.1103/PhysRevA.100.053818
• Jakobsen P. K. and Mansuripur M. On the nature of the Sommerfeld-Brillouin Forerunners (or Precursors). Quantum Stud.: Math. Found. (2019). https://doi.org/10.1007/s40509-019-00210-9
• Mansuripur M. and Jakobsen P. K., An approach to constructing superoscillatory functions, Journal of Physics A: Mathematical and Theoretical, Volume 52, Number 30.(2019),https://doi.org/10.1088/1751-8121/ab27de
• Lin A.,  Kuzmina A. A and Jakobsen P. K. A boundary integral approach to linear and nonlinear transient scattering. Applied Numerical Mathematics 147,2020. https://doi.org/10.1016/j.apnum.2019.08.026
• Lin, A. and Jakobsen P. K. A 3D nonlinear Maxwell's equations solver based on a hybrid numerical method. Physica Scripta, Volume 94, Number 8,  2019. https://doi.org/10.1088/1402-4896/ab166d
• Lin, A. and Jakobsen P. K. On the Ewald Oseen scattering formulation for light scattering: stability, singularity and parallelization. Physica Scripta, Accepted 2019. https://doi.org/10.1088/1402-4896/ab3d0d
• Juhaz D and Jakobsen P. K. Constructing a partially transparen computational boundary for UPPE using leaky modes. Journal of Mathematical Physics 60, 083505, 2019. https://doi.org/10.1063/1.5099193
• Juhaz, D and Jakobsen P. K. Convergence and completeness for square-well Stark resonant state expansions. Journal of Mathematical Physics 59, 113501, 2018. https://doi.org/10.1063/1.5042523
• Mansuripur, M.,Kolesik, M and Jakobsen, P. K. Leaky-mode expansions of the electromagnetic field inside dispersive spherical cavity. Journal of Mathematical Physics, Volume 59, Number 3, 2018. https://doi.org/10.1063/1.5006956
• Jakobsen P. K. The thermodynamics of light. ArXiv 2018. http://www.arxiv.org/physics

• Sørbye, S. H., Illian, J. B., Simpson, D. P., Burslem, D. and Rue, H. Careful prior specification avoids incautious inference for log-Gaussian Cox point processes. Journal of the Royal Statistical Society, Series C, 2018. doi:10.1111/rssc.12321.
• Sørbye, S. H.; Myrvoll-Nilsen, Eirik; Rue, Håvard. An approximate fractional Gaussian noise model with O(n) computational cost. Statistics and computing 2018. doi: 10.1007/s11222-018-9843-1.
• Rypdal, M., Fredriksen H.-B., Myrvoll-Nilsen E., Rypdal K. and Sørbye, S. H. Emergent Scale Invariance and Climate Sensitivity, Climate 6, 93, 2018. (Link til paper) 
• Rypdal, M., Rypdal V., Burney J. A., Cayan D., Bainto E., Skochko S., Tremoulet A. H., Creamean J., Shimizu C., Kim J. and Burns J. C., Clustering and climate associations of Kawasaki Disease in San Diego County suggest environmental triggers, Scientific Reports 8, 16140, 2018. (Link til paper)
• Rypdal, M., Fredriksen, H.-B., Rypdal, K., Steene, R., Emergent constraints on climate sensitivity. Nature 563, E4 - E5, 2018. (Link to paper)
• Devenish G., Ytterstad E., Begley A., Do L., Scott J., Intake, sources, and determinants of free sugars intake in Australian children aged 12–14 months. Matern Child Nutr e12692, 2018. (Link til paper)
• Ytterstad E, Frailty in Survival Analysis of Widowhood Mortality, Journal of Probability and Statistics, 2018, 2378798, 2018. (Link to paper)
• Rypdal, K., Empirical Growth Models for the Renewable Energy Sector. Advances in Geosciences 45, 35- 44, 2018. (Link to paper)
• Rypdal, K., The Life and Death of the Recent Global Warming Hiatus Parsimoniously Explained, Climate 6, 64, 2018. (Link to paper)
• Nilsen, T., Werner, J. P., Divine, D. V., Rypdal M., Assessing the performance of the BARCAST climate field reconstruction technique for a climate with long-range memory, Climate of the Past 14, 947-967, 2018. (Link to paper)  
• Rypdal, V., Arnstad, E. D., Aalto, K., Berntson, L., Ekelund, M., Fasth, A., Glerup, M., Herlin, T., Nielsen S., Peltoniemi, S., Zak, M., Rygg, M., Rypdal, M., Nordal E., Predicting unfavorable long-term outcome in Juvenile Idiopathic Arthritis: Results from the Nordic cohort study, Arthritis Research & Therapy 20, 91, 2018. (Link to paper) 

Popular science (in Norwegian):  

• Et enkelt argument viser at global oppvarming skyldes menneskelig aktivitet (K. Rypdal)
  
• Dødelighet i Norge etter tid på året, ukedag og fødselsdato (T. Brenn og E. Ytterstad)

The research group in the media (in Norwegian):

• Britisk klimastudie avlyste skrekkscenario – norske forskere brukte én uke på å avvise den (NRK 1. novermber 2018)
• Norske forskere: Punkterer «gladnyheten» om begrenset global oppvarming (filternyheter.no 1. november 2018)
• Mange dør av kreft kort tid etter at de mister sitt livs kjærlighet (Dagbladet 10. august 2016)
• UiT-forskning: Du kan dø av knust hjerte (Nordlys 12. mars 2015)
• Enker og enkemenn dør av kreft kort tid etter å ha mistet livsledsageren (iTromsø 2015)
• Høyere dødelighet etter tap av ektefelle (Aftenposten 11. august 2016)