Politics

This revolution has been a long time in the making. Behind it are metrologists working in their scientific laboratories, and scientific managers in their decision-making committees. Now the moment is approaching when many of the old quantities (specifically, the definitions behind them) will have to step down to make way for their successors, who are waiting in the wings. The quantities concerned are the kilogram, the mole, the ampere and the kelvin. The foremost expert committee in the world of metrology, the International Committee for Weights and Measures (Comité international des poids et mesures, CIPM), issued its unequivocal recommendation for this development at its recently concluded annual assembly. It is hoped that, at their general conference next year, the international community of signatories to the Metre Convention will heed the experts’ advice and provide the physical units with an especially firm foundation – one that...

The search goes on. No difference in protons and antiprotons have yet been found which would help to potentially explain the existence of matter in our universe. However, physicists in the BASE collaboration at the CERN research center have been able to measure the magnetic force of antiprotons with almost unbelievable precision. Nevertheless, the data do not provide any information about how matter formed in the early universe as particles and antiparticles would have had to completely destroy one another. The most recent BASE measurements revealed instead a large overlap between protons and antiprotons, thus confirming the Standard Model of particle physics. Around the world, scientists are using a variety of methods to find some difference, regardless of how small. The matter-antimatter imbalance in the universe is one of the hot topics of modern physics.

Pressemitteilung der PTB und BBR

Berlin. Am 10. Oktober 2017 wurde über dem Erweiterungsbau des Willy-Wien-Laboratoriums der Physikalisch-Technischen Bundesanstalt (PTB) der Richtkranz aufgezogen. Der Bau des Labor- und Bürogebäudes mit direkter Anbindung an den benachbarten Elektronenspeicherring im Hauptgebäude wird vom Bundesamt für Bauwesen und Raumordnung (BBR) umgesetzt. 

For the practical use of battery-operated electric vehicles, measurement methods are required which provide fast and reliable information as to whether and to what extent the maximum charging capacity of a Li ion battery has already decreased. This is referred to as the “state of health”. To measure a battery's state of health, PTB has installed a reference measuring set-up that uses electrochemical impedance spectroscopy as well as a model designed to simulate aging.

Die Physikalisch-Technischen Bundesanstalt (PTB) ist bei einer Evaluation durch den Wissenschaftsrat als exzellent bewertet worden. Das heute veröffentlichte Ergebnis übertrifft die Bewertung der ersten Evaluation aus dem Jahr 2008.

The International System of Units (SI) is being fundamentally reformed. In the fall of 2018, a large international conference is going to set the historical course for the future of the SI. The new SI will be based on fundamental constants instead of the seven base units as previously. PTB has accompanied this process by means of various large-scale research projects – among others the Avogadro project for the redefinition of the kilogram and of the mole, and the Boltzmann project for the redefinition of the kelvin. Moreover, PTB has played an important role by providing information on these reforms. PTB has recently published an info sheet about the new SI (in German and in English); you are welcome to order one free of charge from the Press and Information Office or to download it from our website. (www.ptb.de > Press & What's new > Brochures > Brochures on the new International System of Units). The website also contains an extra...

For decades, PTB has been carrying out type approval tests for new speed cameras, traffic light cameras and other measuring instruments used in road traffic before they may be put into operation.

At present, the kelvin is literally based on no more than water – on the triple point of water, to be more precise. The base unit of temperature is therefore dependent on a material whose properties may vary. But this is about to change: In the fall of 2018, the kelvin, as well as all the other units of the International System of Units (SI), will be redefined to rest on a solid and invariable foundation consisting of fundamental constants. The kelvin will be based on the Boltzmann constant, which scientists from the Physikalisch-Technische Bundesanstalt (PTB) have now determined by means of a dielectric-constant gas thermometer with such accuracy that all obstacles to the redefinition of the unit of temperature, the kelvin, have been removed. The results have been published in the current edition of the specialist journal Metrologia.

„Einladung zum Staatsbesuch“– die Gelegenheit für Hunderttausende, mal hinter die Kulissen der Bundesregierung zu blicken.

Im Rahmen des im Metrologischen Forschungsprogramms EMRP geförderten Projekt NEWSTAR wurde experimentell die Berechenbarkeit eines berechenbaren quanteneffizienten Detektors bzgl. seines polarisations-, winkel- und bandbreitenabhängigen Verhaltens überprüft und bestätigt. Die Empfindlichkeit eines Photometers wurde schließlich gegen diesen Detektor kalibriert und das Ergebnis mit dem Wert verglichen, der sich aus der Kalibrierung entsprechend der aktuellen Rückführungskette ergibt, wobei sich eine Übereinstimmung im Rahmen der Messunsicherheit ergab.