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Doktorat na TCfA

administrative steps

• getting documents to Dziekanat + http://irk.umk.pl : deadline 2010: 21.09.2010 (usually around late August/September)
• interview (rozmowy): date 2010: 23.09.2010 (usually mid September)
• more info: http://www.fizyka.umk.pl/wfaiis/?q=node/28 (ignore the old dates: as of summer 2010, instead of 17.09.2009, 22.09.2009 there should be 21.09.2010, 23.09.2010)

conditions

• stipends:
  • normal stipends are only for Polish citizens (EU rules should, in principle, allow other EU citizens, but this may not yet be implemented in national law)
  • stipend only lasts for one year; new competition for stipends each year of doctorate, depending on chance and a supposedly meritocratic points system
• in addition to research, the doctorant must:
  • study several courses and take exams
  • possibly do extra courses with exams if s/he did not study astronomy directly (e.g. physics/maths graduate)
  • carry out many hours of unpaid teaching/tutoring

visits by scientists from Central/Eastern Europe

• Mianowski Fund: 1-12 months research visit, if you already have a position and a degree (master's maybe enough?) in your home country
  • http://www.mianowski.waw.pl/programme.htm

Ewentualny Tematy

Non-perturbative N-body/GR simulations

N-body simulations (e.g. AstroPh:0411043, ArXiv:1105.1082, AstroPh:0111367) used for the modelling of 0.1 to 5 Gpc scale structure formation assume a rigid Friedmann-Lemaitre-Robertson-Walker (FLRW) background against which perturbations grow according to Newtonian gravity, while the FLRW background itself evolves assuming that structure formation do not form. An UMK-Lyon project is underway to develop relativistic methods of correcting N-body simulations for this contradiction, by using scalar averaging (AstroPh:9912347, ArXiv:0707.2153, ArXiv:0803.1401, ArXiv:1203.6263, ArXiv:1303.6193). The main result of the full project (ArXiv:1706.06179) is that more accurate simulations help show that "dark energy" is a misinterpretation of the virialisation epoch, during which much of the most massive galaxies and galaxy clusters formed. The student's contribution would be in checking caveats of this calculational method and/or proposing extensions.

http://cosmo.torun.pl/Cosmo/DoktoratTematy

Measuring metric inhomogeneity with BAO

The Universe is not homogeneous, but the Concordance Model starts with a spatially-homogeneous solution to the Einstein field equations and afterwards applies perturbations. The scalar averaging approach (AstroPh:9912347, ArXiv:0707.2153, ArXiv:0803.1401, ArXiv:1203.6263, ArXiv:1303.6193) proposes a relativistically more realistic approach to cosmological modelling. The initial measurement of a shift of about 6% in the baryonic acoustic oscillation (BAO) peak location (ArXiv:1410.1687) in overdense regions provides the first tentative evidence of metric inhomogeneity. The calculations using the presently available software are cpu-intensive. A student would help develop algorithmic speedups, tests of the different software modules, and possibly GPGPU modules under OpenCL.

http://cosmo.torun.pl/Cosmo/DoktoratTematy