US/Mountain, 28 May - 2 June 2017
- Published on Wednesday, 23 March 2016 18:13
Peering into the future of populations with the help of complex networks of predictive maps
Predicting the future from the present - that’s what logistic maps can do. For example, they can be used to predict the evolution of a population in the near future based on its present situation. They are relevant when studing systems such as entire populations, where the behaviour of the separate units - which have the ability to self-organise - cannot explain the behaviour of the system as a whole. Alexandre L'Her from the University of the Republic, Montevideo, Uruguay, and colleagues have now developed an electronic version of a logistic map that is capable of interacting with many other maps, making the model scalable. As a benchmark to explain new emerging behaviours of entire complex systems, they have studied networks of logistic maps coupled together at various levels. Their findings were recently published in EPJ B and make it possible to more easily compare previous computer simulations with experimental results obtained using this state-of-the art electronic model.
- Published on Tuesday, 22 March 2016 08:47
On the evolution of how we have defined time, time interval and frequency since antiquity
The earliest definitions of time and time-interval quantities were based on observed astronomical phenomena, such as apparent solar or lunar time, and as such, time as measured by clocks, and frequency, as measured by devices were derived quantities. In contrast, time is now based on the properties of atoms, making time and time intervals themselves derived quantities. Today’s definition of time uses a combination of atomic and astronomical time. However, their connection could be modified in the future to reconcile the divergence between the astronomic and atomic definitions. These are some of the observations made by Judah Levine, author of a riveting paper just published in EPJ H, which provides unprecedented insights into the nature of time and its historical evolution.
- Published on Tuesday, 22 March 2016 08:04
The publishers of The European Physical Journal C – Particles and Fields are pleased to announce the appointment of Professors Laura Baudis as new Editor-in-Chief. This follows the splitting of the experimental section into Experimental Physics I: Accelerator Based High-Energy Physics, now led by Jos Engelen, and Experimental Physics II: Astroparticle Physics, now led by Laura Baudis.
Laura Baudis is a Professor at the University of Zurich. Her research interests are in astroparticle physics and cosmology, in particular in the fields of direct dark matter detection and neutrino physics.
- Published on Friday, 11 March 2016 15:06
The new ScientaOmicron LT-UHV scanning tunneling microscope is installed at Pico-Lab CEMES-CNRS (Toulouse) with its 4 STM scanners performing on the same surface. At 4.3 K, we report state-of-the-art STM experiments on Au(111) usually performed on the most stable single tip LT-UHV scanning tunneling microscopes.
Operating the 4 scanners independently or in parallel with an inter tip apex distance lower than 100 nm, the ΔZ stability is better than 2 pm per STM. Single Au atom manipulations were performed on Au(111) recording the pulling, sliding or pushing signal. When contacting one Au ad-atom, a jump to contact leads to a perfect linear low voltage I-V characteristics with no averaging. Two tips surface conductance measurements were also performed with one lock-in and in a floating sample mode to capture the Au(111) surface states via two STM tips dI/dV characteristics. This new instrument is exactly 4 times as precise as a single tip LT-UHV STM.
- Published on Thursday, 03 March 2016 09:35
New factors influencing particle deposition via solvent evaporation and relevant to microchips manufacturing have now been elucidated
Few of us pay attention to the minutiae of coffee stains’ deposition patterns. However, physicists have previously explained the increased deposition of ground coffee particles near the edge of an evaporating droplet of liquid. They attributed it to the collective dynamics of ground coffee grains as the liquid evaporates along the contact line between the liquid coffee and the table. This kind of dynamics also governs microchip production, when particles are deposited on a substrate by means of solvent evaporation. However, until recently, explanations of how such evaporation patterns are formed did not account for the effect of the mutual interactions between electrically charged particles. Now, Diego Noguera-Marín from the University of Granada, Spain, and colleagues have found that particle deposition may be controlled by the interplay between the evaporation of the solvent via convection and the previously identified collective diffusion of suspension nanoparticles. These findings appear as part of an EPJ E topical issue, entitled Wetting and Drying: Physics and Pattern Formation.
- Published on Wednesday, 02 March 2016 10:52
Physicists show that the shape of the air-water interface, when linked to capillarity, influences water retention or evaporation
Water in, water out: such is the cycle of porous material. In some cases, like with soils, it is preferable to keep water in. In others, it makes better economic and ecological sense to have porous materials dry faster, e.g. in the paper industries or with plasterboard manufacturing. Modeling how porous material retains water or dries up can be resolved by narrowing the focus down to a single porous channel; now, a team of physicists has uncovered subtle underlying effects. These include the local shape of the air and water interface, which, in turn, is influenced by the actual shape of the capillaries. Emmanuel Keita, a physicist from Paris-Est University, France, who is also affiliated with Harvard University, Massachusetts, USA, and colleagues have just published these results in EPJ E.
- Published on Tuesday, 01 March 2016 16:54
Scientists leave no stone unturned when studying how a liquid wets a powder
Every cook knows that dissolving powder into a liquid, such as semolina in milk or polenta in water, often creates lumps. What they most likely don’t know is that physicists spend a lot of time attempting to understand what happens in those lumps. In a review paper published in EPJ E, scientists from the École Supérieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI), France, share their insights following ten years of research into the wetting of soluble polymer substrates by droplets of solvents like water.
- Published on Sunday, 28 February 2016 20:41
Nature of interaction of probe molecules on the surface of oxide particles elucidated
Studies of molecules confined to nano- or micropores are of considerable interest to physicists. That’s because they can manipulate or stabilise molecules in unstable states or obtain new materials with special properties. In a new study published in EPJ Plus, Stefan Frunza from the National Institute of Materials Physics in Romania and colleagues have discovered the properties of the surface layer in probe molecules on the surface of oxide particles. These properties depend on the interaction at the interface. In this particular study, probes are formed by adsorption of rod-like cyanophenyl derivates on the surface of oxide particles. The authors found that their surface layers behave like glass-forming liquids.
- Published on Tuesday, 16 February 2016 17:02
EPJ Plus has the great pleasure to announce the appointment of Professor Paolo Biscari as deputy Editor-in-Chief of the journal.
Paolo Biscari is Full Professor in Condensed Matter Physics at the Department of Physics of the Politecnico di Milano. At Politecnico di Milano he is Dean of the PhD School, which coordinates the researches of approximately 900 PhD candidates. He is Deputy Editor-in-Chief of the European Physical Journal Plus, and member of the Editorial Board of the Springer Book Series "Unitext". His research is focused in the soft matter area, and more specifically in liquid crystals, elastomers, and critical phenomena. He has been Invited Professor at the Universities of Southampton and Minnesota, has published more than 60 research papers in international peer-reviewed journals, three books, and has contributed to approximately 50 international congresses as Invited Speaker. He has directed as PI several research grants and contracts, awarded from both public Institutions and private companies. In 2004, he earned the Bruno Finzi Prize, awarded by the Istituto Lombardo, Accademia di Scienze e Lettere, for his research in Applied Mechanics.
- Published on Monday, 15 February 2016 11:29
This EPJ B Colloquium article explores applications of the Self-Consistent Random Phase Approximation (SCRPA) approach to Fermi systems with a continuously broken symmetry. Correlations beyond those considered by standard Random Phase Approximation (RPA) are summed up, thereby correcting for the quasi-boson approximation in standard RPA.