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The increased accuracy of the experiments studying parity non-conserving effects in atoms calls for improvement also in the atomic calculations which are necessary to connect the experimental results to fundamental parameters. We show how the method of iterative solution of the two-dimensional “pair equation” can be used to treat the effect of pair correlation to all orders, also in the calculatio
The search for weak-interaction-induced atomic parity nonconservation, initiated in the 1970s, challenges both theory and experiment Since the weak interaction is very short range, the atomic effects increase rapidly with nuclear charge, as Z3. The focus has thus been on heavy atoms, where relativistic effects are essential, and nuclear size must be taken into account. The generalization of atomic
Current physics textbooks tend to exclude military applications, but it is explained here how a study of the Manhattan project-the devastatingly successful attempt to develop an atomic bomb-can show students how the lives and work of physicists are shaped by events in society. Much of the original source material is available in books and on the internet (and referenced here), which allows student
Many modern rollercoasters feature loops. Although textbook loops are often circular, real rollercoaster loops are not. In this paper, we look into the mathematical description of various possible loop shapes, as well as their riding properties. We also discuss how a study of loop shapes can be used in physics education.
A carousel gives possibilities to explore physics in rotating systems and to gain first-hand experience of methods to measure rotation, without the need for an external reference. This paper discusses the Foucault pendulum, as well as the sideways deflection of horizontally and vertically moving objects in a rotating system. These experiments lay the foundation for an understanding of ways to demo
The development of a national supercomputing center is expected to enable users with large scale computing needs to perform tasks that would otherwise be out of reach. To this end, the center provides computers with much better performance than would otherwise be available to the user. The actual processing speed of the computer is given priority, even if this may be at the cost of a reduction in
An amusement park is a large physics laboratory, full of rotating and accelerated coordinate systems. The forces are experienced throughout the body and can be studied with simple equipment or with electronics depending on age and experience. In this paper, we propose adaptations of classical physics experiments for use on traditional rides.
Nuclear distributions affect many aspects of atomic spectra, making atomic physics a useful tool to study also nuclear properties. Relativistic coupled-cluster calculations for the 7s and 7p states in Fr are presented and applied to binding energies, and to electronic factors for the field isotope shift. The result, Fκ = -21.0 GHzfm-2 for the 7s-7p3/2 transition, leads to revised values for the ch
A diagonalisation procedure of the Foldy-Wouthuysen type is considered for the single-electron Dirac Hamiltonian as a basis for many-body applications. A modified procedure is suggested. In the diagonalisation procedure the Dirac equation is completely decoupled into two equations of the Pauli type. The expressions for positive- and negative-energy projection operators in the transformed basis are
INTRODUCTION: Endovascular thrombectomy (EVT) is a significant improvement in the care of acute ischemic stroke (AIS) patients, but only a small portion of patients receive treatment. Our aim was to analyze EVT implementation in Sweden according to a set of key performance indicators (KPIs) for procedural and implementational effectiveness. METHODS: A nationwide prospective registry-based observ
This paper provides an overview of both long-standing and new legal and policy developments concerning Environmental Human Rights Defenders (EHRDs). The focus is on four major components: i) observing different approaches and understandings about EHRDs; ii) analysing the content of international obligations concerning EHRDs and mechanisms for reviewing implementation and accountability; iii) discu
Background: The EAT-Lancet Commission has proposed a global reference diet aimed at promoting both human health and environmental sustainability. While adherence to this dietary pattern has been associated with reduced risks of chronic disease and lower environmental impact, concerns remain about its ability to meet nutritional requirements - particularly among older adults. The aim was to explore
Human diets play a crucial role in both human health and environmental sustainability. In 2019, the EAT-Lancet Commission on healthy diets from sustainable food systems introduced the EAT-Lancet planetary health diet, a universal reference diet designed to promote human health while minimizing environmental degradation. It is a predominantly plant-based dietary pattern, rich in whole grains, veget
Background and aims: The EAT-Lancet Commission proposed a healthy dietary pattern to prevent diet-related diseases while promoting planetary sustainability, but little is known regarding its associations with type 2 diabetes (T2D) and metabolic dysfunction-associated steatotic liver disease (MASLD), both of which are highly prevalent and frequently co-exist. We aimed to assess association of this
In Memoriam
Introduction Cluster analysis, a machine learning-based and data-driven technique for identifying groups in data, has demonstrated its potential in a wide range of contexts. However, critical appraisal and reproducibility are often limited by insufficient reporting, ultimately hampering the interpretation and trust of key stakeholders. The present paper describes the protocol that will guide the d
