Replacing the Ur-Kilogram with High-Precision: The new system of units and the precise determination of the defining constants
Lecturer: Prof. Braun-Munzinger, Prof. Stachel, Prof. Schultz-Coulon
Link to LSF
Recent decisions of the General Conference on Weights and Measures of the Metre Convention have
opened the door to a fundamental change of the International System of Units, the SI, in 2018. The
revised SI will be based on fixing the numerical values of seven defining constants corresponding to
the seven traditional base units. This will bring about basic modifications in the definition of the
kilogram, the ampere, the kelvin, and the mole and will have consequences for units derived from
them. In contrast, the second, the meter, and the candela will not be affected.
[...] Benefits and a wide-reaching impact for the realization and dissemination of the units are
anticipated because innovative technologies with ever-increasing accuracy will emerge, enabling the
direct realization over widespread measurement ranges without the definitions themselves having to
[cited from: J. Stenger and J.H. Ullrich, Annu. Rev. Condens. Matter Phys. 2016.7:35-59. ]
The seminar will discuss the new definition of the SI units and the precise determination of the
defining constants. The following topics will be discussed:
Comprehensive reviews of all seminar topics are available online in
Annalen der Physik,Volume 531, Issue 5, Special Issue: The Revised SI: Fundmental
Constants, Basic Physics and Units and PTB Mitteilungen 2016 Heft 2
Dates and venue:
The seminar is scheduled for Fridays, 13:15 to 15:00.
More details will be announced in due time.
The seminar will start on Friday, 21/10/2022 with the assignments of the topics.
Please follow this link for the registration.
Topics & Schedule:
|02.12.2022||Introduction to the revised SI system||Peter Braun-Munzinger|
|09.12.2022||The Second and the hyperfine transition in Cs||Anton Eberhardt, Paul Zürn|
|16.12.2022||The Meter and speed of light||Malte Schneider, Magdalena Winkelvoß|
|13.01.2022||The Mole and the Avogadro project||Johanna Stachel|
|20.01.2022||The Kilogram and the Planck constant||Jelte Jan Luca Duchene, Joschka Johannes Goes|
|Bonus: On Leap Seconds||Peter Braun-Munzinger|
|27.01.2022||The Ampere and the elementary charge||Kunal Bhatia, Wing Hong Hung|
|03.02.2022||The Kelvin and the Boltzmann constant||Poppy Fay Hicks, Ashish Pradeep Jadhav|
|Not covered||The Candela and the luminous efficacy of radiation|
- Group Seminar (coulon)
Braun-Munzinger, Stachel, Schultz-Coulon
Link zum LSF