School of Physical and Chemical Sciences Te Kura Matū Seminar Series

From the Schrödinger Equation to the Standard Model and Beyond


Peter Schwerdtfeger


Centre for Theoretical Chemistry and Physics, The New Zealand Institute for Advanced Study (NZIAS), Massey University Albany

Time & Place

Fri, 23 Aug 2019 11:00:00 NZST in Room 701, Level 7, WEST

All are welcome


The Schrödinger equation has served us well for almost a century now with results for molecular and bulk phase properties in often-spectacular agreement with experiment [[1]]. Over the last 40 years we had to learn how to deal with its covariant relativistic extension, the many-electron Dirac equation, and its associated negative energy continuum [[2]]. Relativistic effects are important in heavy (and superheavy) element chemistry [[3]], for example mercury is a liquid and superheavy element oganesson is rare but not a gas at room temperature because of relativistic effects [[4],[5]]. Even further up the theory ladder, effective schemes for treating bound state quantum electrodynamics for many-electron systems become slowly available for an accurate atomic and molecular many-body treatment [[6],[7],[8]]. These theories have as a basic ingredient the interaction picture for treating quantum fields, which has its known limitations (Haag’s theorem). Extending the fields even further to weak interactions, we can start to address fundamental questions like the left-right symmetry breaking in chiral molecules (parity violation) and its possible role in the appearance of biomolecular homochirality [[9]]. Even higher up, the so-called standard model of physics unifies three of the four fundamental forces in nature, the electromagnetic, the weak and the strong force. The standard model is incomplete however (beside the missing gravitational force), and most see it as an unnecessary patchwork of terms (kinetic, interaction, pure field and Higgs terms and perhaps more). Its predictive power rests on the regularisation of divergent quantum corrections and the renormalisation procedure introducing scale–dependent “running coupling constants”. Despite its known incompleteness, the standard model has been incredibly successful. The search for new physics beyond the standard model therefore constitutes one of the most challenging and exciting areas in modern quantum field theory. Prime examples include the study of exotic particle decays, the search for the electron electric dipole moment, and the variation of fundamental constants in space-time, where our research group is currently active in [[10],[11]]. Here accurate relativistic quantum theoretical calculations can help to search for suitable molecular candidates to detect such tiny effect for the first time in interstellar space or in the laboratory. The fine-tuning of the fundamental constants is essential for the existence of life in our universe, related to the weak anthropic principle.

[1] P. Schwerdtfeger, R. Tonner, G. A. Moyano, E. Pahl, Angew. Chem. Int. Ed. 55 (2016) 12200.

[2] P. Schwerdtfeger, L. F. Pašteka, A. Punnett, P. Bowman, Nucl. Phys. A 944 (2015) 551.

[3] P. Pyykkö, Chem. Rev.8 (2017) 1407.

[4] K. G. Steenbergen, E. Pahl P. Schwerdtfeger, J. Phys. Chem. Lett.8 (2017) 1407.

[5] O. Smits, P. Jerabek, E. Pahl P. Schwerdtfeger, in preparation.

[6] V. V. Flambaum, J. S. M. Ginges, Phys. Rev. A 72 (2005) 052115.

[7] V. M. Shabaev, I. I. Tupitsyn, V. A. Yerokhin, Phys. Rev. A 88 (2013) 012513.

[8] C. Thierfelder, P. Schwerdtfeger, Phys. Rev. A 82 (2010) 062503.

[9] B. Darquié, C. Stoeffler, S. Zrig, J. Crassous, P. Soulard, P. Asselin, T. R. Huet, L. Guy, R. Bast, T. Saue,

   P. Schwerdtfeger, A. Shelkovnikov, C. Daussy, A. Amy-Klein, C. Chardonnet, Chirality 22 (2010) 870.

[10] L. F. Pašteka, A. Borschevsky, V. V. Flambaum, P. Schwerdtfeger, Phys. Rev. A 92 (2015) 012013.

[11] J.-P. Uzan, Living Rev. Relat. 14 (2011) 2.


Learn more about Peter Schwerdtfeger here.