Background: Who was Heisenberg?
Werner Karl Heisenberg was a German physicist born on December 5, 1901. He was well-known for his formulation of quantum mechanics and was hugely involved in its inception during the twentieth century. Heisenberg went on to win the Nobel Prize in Physics for his contributions.
He is best known for the eponymous Heisenberg uncertainty principle, a result that is fundamental to the study of quantum physics.
Werner Karl Heisenberg had an immensely significant career and made numerous significant developments in the field of physics. In the following article, we mark his birth month by discussing and celebrating his life, career and its long-lasting significance.
Early Career
Heisenberg was born in Würzburg, Germany, on the 5th of December, 1901, to his parents, August Heisenberg and Anna Wecklein.
He attended the University of Munich and studied under German physicist Arnold Sommerfeld. Sommerfeld is well known for his work in atomic physics and in particular, the Bohr-Sommerfeld model of the atom which was postulated to help explain certain characteristics of atomic spectra. Werner Heisenberg was only 21 in 1923, when he received his PhD in physics.
Over the next two years, Heisenberg worked as an assistant to Max Born at the University of Göttingen, with whom he had originally started working in 1922, while he was still a doctoral student. He met Danish physicist Niels Bohr at Göttingen, with whom he worked after receiving a Rockefeller Grant.
In 1925, returning from his visit to Bohr’s Institute for Theoretical Physics, Heisenberg began work on his breakthrough formulation of quantum mechanics, leading to his winning the 1932 Nobel Prize.
Heisenberg went on to become a professor in 1927 and later , during the Second World War, was involved in German atomic weapons research. The latter of these has been subject to intense controversy. The most significant aspects of Heisenberg’s scientific career are discussed in subsequent sections.
Major Scientific Contributions
As previously stated, Werner Heisenberg was awarded the 1932 Nobel Prize for the work he did in his formulation of quantum mechanics. While numerous people were involved in developing a formalism for quantum mechanics at the time, Heisenberg’s success lay in postulating quantum mechanics using matrix algebra. His work in the field has been revolutionary, leading to him being widely regarded as a founder of quantum mechanics.
It is fascinating to realize that objects in linear algebra, such as matrices, were not used extensively outside of pure mathematics prior to Heisenberg’s 1925 paper. Today, matrix algebra appears in virtually every corner of physics, and linear algebra is an indispensable tool for physicists.
1927 saw the inception of what is arguably Heisenberg’s best-known contribution to the field of physics: the Heisenberg Uncertainty Principle. The uncertainty principle imposes a limit to how precisely a particle’s state can be known. To be specific, it states that one cannot determine both the position and the momentum of a given particle with arbitrary precision. What is interesting is that this is a result of the fundamental nature of all matter and cannot be attributed to technological defects.
The uncertainty principle leads to a number of profound physical realizations. The uncertainty principle applies to quantum-scale objects; once you get to a small enough scale, it just so happens that knowing the position of a particle relatively well implies that you lose information about its momentum and vice versa.
The implications of the uncertainty principle are huge. In particular, it causes us to lose determinism. The simple fact that we cannot arbitrarily know the position and momentum of an object means that we cannot, with absolute precision, predict how it evolves, and therefore, our ability to “determine” outcomes is lost. This is a deeply fundamental result that is quite intrinsically linked to the probabilistic nature of quantum physics.
Soon after, Heisenberg became a professor and worked on developing a Quantum Field Theory. Heisenberg would go on to publish numerous papers on high-energy cosmic rays throughout the 1930s, before the dawn of the Second World War, which threw him into a highly controversial period of his life.
Heisenberg during World War II
During World War II, Heisenberg worked on the German nuclear weapons program. His involvement was strange, given that Heisenberg had previously been subject to ideological attacks by Nazi-aligned physicists, due to his field of physics involving numerous abstract mathematical concepts, which was regarded by a small subset of people, as being a result of “Jewish influence.” While Heisenberg never openly promoted the ideals of the Nazi Party, his involvement has been subject to intense controversy.
There is speculation that Heisenberg was involved in intentionally sabotaging the project, owing to the fact that the German effort was as a whole unsuccessful and later reviews of their work revealed several critical flaws. However, this remains unconfirmed.
Heisenberg was briefly captured by American intelligence in 1945 due to his involvement with the nuclear weapons programme and was interned with other German physicists in England. He was released in 1946, after which he returned to his previous position at the, as it was then known, Kaiser Wilhelm Institute. It was soon renamed the Max Planck Institute for Physics.
Later Life
Werner Heisenberg went on to take up several administrative roles, becoming the president of the German Research Council. He was also heavily involved in German efforts towards the creation of the European Council for Nuclear Research (CERN).
Heisenberg’s post-war research interests included atomic and plasma physics, as well as developing an understanding of elementary particles. Heisenberg was one of many physicists who attempted to develop a quantum field theory at that time. He also proposed a Unified Field Theory, and was in favour of symmetry-based approaches to particle physics. His theory, however, received minimal support.
Conclusions
Werner Heisenberg passed away in 1976 at the age of 74 in Munich, Germany. His contributions to the field of quantum physics remain unmatched. It is an understatement to say that his development of quantum mechanics was revolutionary and has had a profound impact on how physics is approached. Few can hope to achieve the level of impact Heisenberg achieved in his time, as one of the most influential physicists of the 20th century.
References
[1] Caltech. n.d. “What Is the Uncertainty Principle and Why Is It Important?” Caltech ScienceExchange. https://scienceexchange.caltech.edu/topics/quantum-science-explained/uncertainty-principle.
[2] The Editors of Encyclopedia Britannica. 2019. “Uncertainty Principle | Definition & Equation.” In Encyclopædia Britannica. https://www.britannica.com/science/uncertainty-principle.
[3] “The Nobel Prize in Physics 1932.” 2019. NobelPrize.org. Elsevier Publishing Company. 2019. https://www.nobelprize.org/prizes/physics/1932/heisenberg/biographical/.
[4] “Werner Heisenberg.” 2019. Atomic Heritage Foundation. 2019. https://www.atomicheritage.org/profile/werner-heisenberg.
Image Citations
[1] Nobel Foundation Archive. n.d. Werner Heisenberg. Https://Www.nobelprize.org/Prizes/Physics/1932/Heisenberg/Biographical/. Accessed December 9, 2022.