Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Extremely dense - approaching a poorly understood state of matter

23.09.2015

Breakthrough in the description of warm dense matter

A team from the Institute of Theoretical Physics and Astrophysics at Kiel University, headed by Professor Michael Bonitz, has now been able to discover new findings on so-called warm dense matter. Physicists use this term to describe a state of matter that differs completely from those solid, liquid or gas states or plasmas known on earth.


Some of the authors shown in front of a poster explaining their new findings, from left to right: Prof. Michael Bonitz, Tim Schoof und Simon Groth. Photo: Dr. Hanno Kählert

Warm dense matter displays characteristics of all other physical states at the same time, in apparent contradiction. The Kiel-based scientists have now developed a new simulation technique which overcomes the inaccuracies of existing theoretical models in describing this state of matter. They have published their research findings in the current edition of the journal Physical Review Letters.

With a density of up to a thousand times more than normal solids, warm dense matter is extremely dense. It exists, for example, as a consequence of the enormous gravitation inside dwarf stars. In lab experiments, this state can be created for short periods of time, in the nano- to microsecond range, under the influence of high intensity laser radiation. Long enough for researchers across the world to probe this state of matter with experiments or computer simulations.

"Exact knowledge about warm dense matter is the key to answering many astrophysical questions. For example, it helps us to determine how old galaxies are, and is also essential for technological applications such as inertial confinement fusion or for understanding how materials behave under extreme pressure", says Bonitz, to classify the significance of the findings.

Previous theoretical models were only able to produce approximate information on the characteristics of warm dense matter. The reason for this is the particular complexity of the interaction between the constituent particles, but especially the behaviour of the electrons involved. They strongly interact with each other and, at the same time, are governed by the laws of quantum mechanics, so that until now they could not be described reliably using existing models.

Thanks to the new simulation method it is now possible to better understand the results of experiments and to make reliable predictions for new measurements. The Kiel-based research group's approach avoids the simplifications used in previous theoretical models.

"It is therefore justified to regard our approach as a computer experiment that produces exact results", Bonitz continues. These findings made at Kiel University now form the basis for improving the existing and developing new numerical methods that will allow for a complete description of warm dense matter in the future.

Original publication:
Schoof, T., Groth, S., Vorberger, J. and M. Bonitz (2015): Ab Initio Thermodynamic Results for the Degenerate Electron Gas at Finite Temperature, Physical Review Letters 115.
Link: http://dx.doi.org/10.1103/PhysRevLett.115.130402

Contact:
Prof. Michael Bonitz
Institut für Theoretische Physik und Astrophysik,
Universität Kiel
Tel.: +49 (0)431/-880-4122
E-mail: bonitz@theo-physik.uni-kiel.de

More information:

The Bonitz Group, Institute of Theoretical Physics and Astrophysics:
http://www.theo-physik.uni-kiel.de/~bonitz/

Details, only a millionth fraction of a millimetre small: This is what Kiel University's research focus "Kiel Nano, Surface and Interface Science" (KiNSIS) is busy investigating. In the nano cosmos, other than in our macroscopic world, the rules of quantum physics apply. In KiNSIS, material scientists, chemists, physicists, biologists, electrical engineers, information scientists, food scientists and physicians work closely together. They aim at understanding systems in the nano dimension and turning knowledge into applications. Molecular machines, novel sensors, bionic materials, quantum computers, advanced therapies and much more can emerge from this endeavour.
More information at www.kinsis.uni-kiel.de/en

Christian-Albrechts-Universität zu Kiel
Press, Communication and Marketing, Dr Boris Pawlowski, Text/editing: Christian Urban
Postal address: D-24098 Kiel, Germany, Telephone: +49 (0)431 880-2104, Fax: +49 (0)431 880-1355
E-mail: presse@uv.uni-kiel.de, Internet: www.uni-kiel.de, Jubilee: www.uni-kiel.de/cau350
Twitter: www.twitter.com/kieluni , Facebook: www.facebook.com/kieluni

Dr. Boris Pawlowski | Christian-Albrechts-Universität zu Kiel

More articles from Physics and Astronomy:

nachricht Seeing the quantum future... literally
16.01.2017 | University of Sydney

nachricht Airborne thermometer to measure Arctic temperatures
11.01.2017 | Moscow Institute of Physics and Technology

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

Im Focus: Bacterial Pac Man molecule snaps at sugar

Many pathogens use certain sugar compounds from their host to help conceal themselves against the immune system. Scientists at the University of Bonn have now, in cooperation with researchers at the University of York in the United Kingdom, analyzed the dynamics of a bacterial molecule that is involved in this process. They demonstrate that the protein grabs onto the sugar molecule with a Pac Man-like chewing motion and holds it until it can be used. Their results could help design therapeutics that could make the protein poorer at grabbing and holding and hence compromise the pathogen in the host. The study has now been published in “Biophysical Journal”.

The cells of the mouth, nose and intestinal mucosa produce large quantities of a chemical called sialic acid. Many bacteria possess a special transport system...

Im Focus: Newly proposed reference datasets improve weather satellite data quality

UMD, NOAA collaboration demonstrates suitability of in-orbit datasets for weather satellite calibration

"Traffic and weather, together on the hour!" blasts your local radio station, while your smartphone knows the weather halfway across the world. A network of...

Im Focus: Repairing defects in fiber-reinforced plastics more efficiently

Fiber-reinforced plastics (FRP) are frequently used in the aeronautic and automobile industry. However, the repair of workpieces made of these composite materials is often less profitable than exchanging the part. In order to increase the lifetime of FRP parts and to make them more eco-efficient, the Laser Zentrum Hannover e.V. (LZH) and the Apodius GmbH want to combine a new measuring device for fiber layer orientation with an innovative laser-based repair process.

Defects in FRP pieces may be production or operation-related. Whether or not repair is cost-effective depends on the geometry of the defective area, the tools...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

Multiregional brain on a chip

16.01.2017 | Power and Electrical Engineering

New technology enables 5-D imaging in live animals, humans

16.01.2017 | Information Technology

Researchers develop environmentally friendly soy air filter

16.01.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>