Superposition Composition

In quantum mechanics, superposition describes the state in which a system exists in multiple states simultaneously until a measurement is made, determining its final state. Repeated measurements reveal probabilities, which in turn define the weighting of the final state. »Superposition Composition« is an artistic-scientific experiment that translates the quantum mechanical principle of superposition into a musical form. As ZKM’s contribution of the UNESCO Quantum Year 2025, it will be performed at least twice daily from April to December, racking up over 500 performances – and thus, measurements.

The composition of the approximately 10-minute piano piece »Superposition Composition« by composer Jia Liu includes built in variations, which are determined for each performance using true random numbers calculated by a quantum computer. As a result, every performance differs from all previous ones and simultaneously acts as a measurement of the acoustic quantum system, resolving the superposition of possible composition modules into a fixed playable state. Only after a large number of performances/measurements does the final form of the composition crystallize through the frequency of played variations.

The resulting final composition from these measurements will be presented in a performance in December, with the composer in attendance. An accompanying data visualization, along with explanatory materials, will complement the installation.

The »Superposition Composition« project makes the abstract principle of superposition—one of the fundamental elements of quantum mechanics—tangibly perceptible during the UNESCO Quantum Year 2025. Through repeated performances and the gradual emergence of the final composition, the process of probability formation becomes both audible and comprehensible. This creates a new awareness of uncertainty and decision-making processes in art while fostering an understanding of physical concepts and future technologies. The project aims to connect science and art, making them accessible to a broad audience—not only through knowledge transfer but also by creating an immersive experience that blends cognitive learning with sensory-acoustic perception.

Open Hertzlab: April 11, 2025, 3 pm in the Hertzlab
Lecture by Jia Liu

Premiere: 12.04.2025, 11 am Music Balcony at the ZKM
From then on, »Superposition Composition« can be enjoyed daily at 11 am and 5 pm until December 2025.

re:publica 2025 in Berlin
Alongside the installation in Karlsruhe, the work will also be presented at re:publica 2025 in Berlin. It can be experienced on site throughout the festival and the sound “measurements” will be made accessible to the public there in a special “festival edition”.

Superposition Composition (AT), a production by ZKM | Hertzlab, 2025