2022 Impact factor 1.6
Condensed Matter and Complex Systems

EPJ E Highlight - Modelling vibration patterns in granular materials

Building statistical models of grain behaviours

The ‘Laguerre ensemble’ statistical model can better describe the vibrational patterns of granular materials at a critical point of transition in their behaviour.

Granular materials are collections of solid particles which can behave in similar ways to both solids and liquids via interactions between grains. Previously, researchers have explored how the behaviours of these materials can be described in the language of statistical mechanics.

Through new research published in EPJ E , Onuttom Narayan at the University of California, together with Harsh Mathur at Case Western Reserve University, show how the characteristic vibrational patterns associated with granular materials at the point where they transition to more solid-like states can be reproduced more accurately. The work could help researchers to gain a deeper understanding of how granular materials behave.


EPJ PV Highlight - Communication on the potential of applied PV in the European Union: Rooftops, reservoirs, roads (R3)

Communication on the potential of applied PV in the European Union: Rooftops, reservoirs, roads (R3)

‘Communication on the potential of applied PV in the European Union: Rooftops, reservoirs, roads (R3)’ is a study conducted by the European Commission’s Joint Research Centre (JRC) that aims to assess the technical capacity potential of these three photovoltaic (PV) applications. The results were published recently in EPJ Photovoltaics.
Renewable energy technologies, like solar panels, are important for meeting the increasing demand for electricity and helping to combat climate change. The European Union (EU) has set ambitious targets for PV installation, but there are challenges to overcome, including competition for land and potential environmental drawbacks.
Indeed, the EU Solar Energy Strategy has outlined solid plans for PV installation, aiming for 385 GWDC (320 GWAC) by 2025 and 720 GWDC (600 GWAC) by 2030. While striving to meet these targets, it is crucial to ensure that the adoption of renewable energy sources does not adversely affect the environment and biodiversity, in accordance with EU policies on nature and wildlife conservation.


EPJ H Highlight - Tracing the history of perturbative expansion in quantum field theory

Perturbative expansions enabled the development of the Standard Model. Source: https://upload.wikimedia.org/ wikipedia/commons/0/00/Standard_ Model_of_Elementary_Particles.svg

Contrary to long-standing assumptions, simplified descriptions of quantum systems have played a central role in shaping the foundations of quantum field theory.

Perturbative expansion is a valuable mathematical technique which is widely used to break down descriptions of complex quantum systems into simpler, more manageable parts. Perhaps most importantly, it has enabled the development of quantum field theory (QFT): a theoretical framework which combines principles from classical, quantum, and relativistic physics, and serves as the foundation of the Standard Model of particle physics.

Yet despite its importance in shaping our understanding of the universe, the role of perturbative expansion has often been understated when discussing the mathematical and philosophical foundations of QFT. Through new analysis published in EPJ H: Historical Perspectives on Contemporary Physics, James Fraser at the University of Wuppertal, together with Kasia Rejzner at the University of York, bring the special status of perturbative expansions into sharper focus, by highlighting their deep-rooted relationship with the foundations of QFT.


R. Egger and H. Rieger
Thank you for the very fruitful and efficient collaboration. It has been a pleasure!!

Paul van Loosdrecht, Guest Editor Topical issue: Excitonic Processes in Condensed Matter, Nanostructured and Molecular Materials, 2013

ISSN (Print Edition): 1434-6028
ISSN (Electronic Edition): 1434-6036

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