38 research outputs found
On the use of real-time mortality data in modelling and analysis during an epidemic outbreak - underlying data
No full textThis project contains the primary data set analyzed in the paper "On the use of real-time mortality data in modelling and analysis during an epidemic outbreak ". The data was generated by downloading the DT-series daily from the Public Health Agency of Sweden between 2020-04-02 and 2020-07-09.
This project contains the following files:
FHM_Covid_Download.zip. (Zip-archive of raw downloaded files with Swedish deaths data.)
swedish_covid_deaths_data.csv. (Swedish deaths data collated from the raw data files in a .csv format.)
swedish_covid_deaths_data.xlsx. (Swedish deaths data collated from the raw data files in a .xlsx format.)
swedish_covid_deaths_OGR.R. (R-script to generate graphs and nowcasts in the paper.)
MDAR author checklist.pdf (Completed MDAR reporting checklist
Non-Perturbative Quantum Field Theory in Extreme Environments
No full textThe aim of this thesis is to describe some physical systems which can be treated by non-perturbative methods in quantum field theory. In the thesis we study systems described by quadratic Hamiltonians, possibly extended with an external electromagnetic field and/or with a thermal heat bath. We also study the (mass less) Schwinger model and boson stars. Apart from the Schwinger model, the systems all have extreme environments. For example, electric field strengths of 1016 V/cm and magnetic field strengths of 109 T as well as temperatures of 109 K are considered. A good conceptual basis for non-perturbative methods in quantum field theory is the functional Schrödinger representation. It is also well-suited for discussing equilibrium as well as out-of-equilibrium statistical mechanics in quantum field theory by means of density matrices. In the thesis we review and develop the functional Schrödinger representation and introduce the so called fermionic field basis. We also extend the analysis to include external electromagnetic fields. Using this setup we study the problem of pair production in an external electric field at finite temperature. It is found that the production of bosons is enhanced at finite temperature while it is suppressed for fermions. We stress the importance of a finite time analysis. In the thesis we also solve the Schwinger model within the functional representation in terms of fermionic variables. In particular the gauge-invariant ground-state functional is found. Moreover, we derive bosonisation rules in this formalism. A system which is studied extensively in the thesis is the charged relativistic boson gas in an external magnetic field. We discuss its thermal properties as well as the properties of the ground state (vacuum). It is found that the magnetisation of the vacuum dominates over the thermal magnetisation at magnetic fields strong enough. The question of condensation in a magnetic field is also addressed. It is verified that `true' Bose-Einstein condensation is impossible in a magnetic field, no matter how weak. However, since there are no discontinuities in the real world, it is shown that the question is somewhat academical. Finally, we review and study compact charged boson stars. It is shown that the vacuum in the presence of a very compact star is unstable and particles are produced. Numerical evidence for a complete screening of the star by the produced particles is found
Non-Perturbative Quantum Field Theory in Extreme Environments
No full textThe aim of this thesis is to describe some physical systems which can be treated by non-perturbative methods in quantum field theory. In the thesis we study systems described by quadratic Hamiltonians, possibly extended with an external electromagnetic field and/or with a thermal heat bath. We also study the (mass less) Schwinger model and boson stars. Apart from the Schwinger model, the systems all have extreme environments. For example, electric field strengths of 10<sup>16</sup> V/cm and magnetic field strengths of 10<sup>9</sup> T as well as temperatures of 10<sup>9</sup> K are considered.<p /> A good conceptual basis for non-perturbative methods in quantum field theory is the functional Schrödinger representation. It is also well-suited for discussing equilibrium as well as out-of-equilibrium statistical mechanics in quantum field theory by means of density matrices. In the thesis we review and develop the functional Schrödinger representation and introduce the so called fermionic field basis. We also extend the analysis to include external electromagnetic fields.<p /> Using this setup we study the problem of pair production in an external electric field at finite temperature. It is found that the production of bosons is enhanced at finite temperature while it is suppressed for fermions. We stress the importance of a finite time analysis.<p /> In the thesis we also solve the Schwinger model within the functional representation in terms of fermionic variables. In particular the gauge-invariant ground-state functional is found. Moreover, we derive bosonisation rules in this formalism.<p /> A system which is studied extensively in the thesis is the charged relativistic boson gas in an external magnetic field. We discuss its thermal properties as well as the properties of the ground state (vacuum). It is found that the magnetisation of the vacuum dominates over the thermal magnetisation at magnetic fields strong enough. The question of condensation in a magnetic field is also addressed. It is verified that `true' Bose-Einstein condensation is impossible in a magnetic field, no matter how weak. However, since there are no discontinuities in the real world, it is shown that the question is somewhat academical.<p /> Finally, we review and study compact charged boson stars. It is shown that the vacuum in the presence of a very compact star is unstable and particles are produced. Numerical evidence for a complete screening of the star by the produced particles is found
Children per se or as periphrasis? A study on the use of ’children’ in five stories from the synoptics
No full textThe purpose of this study is to examine the intention of the synoptic’ use of ’children’ in five selected stories: ’Jesus and the children’, ’Who is the greatest?’, ’The entrance ticket of heaven’, ’The demand of discipleship’ and ’The child Jesus’. It is inspired by the texts where Jesus seems to love the little children very much and yet he requires his disciples to abandon their own children for his sake.
What were the synoptic’ intentions of the use of ‘children’ in these stories? Was it to show the great love Jesus had for children per se or were the children only a periphrasis, a symbolization using their properties?
When first reading the stories about Jesus and children it seems that the synoptics were describing children per se; but through exegetic studies and reading the works of some earlier scholars I have come to the conclusion that the synoptics did not intend to show Jesus as an extraordinary man who, unlike the Jews or Romans, loved or treated children so much more.
Instead the study shows that the synoptics more likely had the intention of using children as a periphrasis: to be able to enter the Kingdom of God you have to adopt the properties of a small child whose needs are very basic and in total dependence of its caregivers to survive.
The synoptics doesn’t say anything about gender or class, but they tell us by their words that the children are small: seven years, but probably even younger. Children in those days probably had the same status as slaves, but Jewish children had a slightly higher status and position in their families.
The conclusion of the study shows that the synoptics used children as periphrasis in two
cases: ’Jesus and the children’, ’Who is the greatest?’ (those who at first seemed to be the opposite). They use children per se in the texts about ’The entrance ticket of heaven’ and ’The demand of discipleship’. Finally I have come to the conclusion that the last story about Jesus as a child deals with both of them: per se and periphrasis
