Unexpected harmonies

Emotionless physics data can be transformed through a process called sonification. Chris Henschke uses this to tease the music out of light.

Illustration by Olivia Baenziger

Illustration by Olivia Baenziger

It may have crashed the Synchrotron, but the experiment was still a success. The scientists cheered; “It’s your first beam dump! Woohoo!”

On the final day of his residency at the Australian Synchrotron, multimedia artist Chris Henschke joined the ranks of a special group of physicists — those who have meddled with the high energy electron beam of the particle accelerator, and caused it to crash into the walls of the vacuum chamber in which it exists. Ultimately, a harmless error that can occur during experiments, but a headache nonetheless.  

It was summer, and it had been one of those oppressively hot Melbourne days. Earlier, Henschke had been out in the car park listening to cicadas humming in the sun and wondered if a synchrotron's tune might sound like that, if it was audible. Synchrotrons are large circular machines that accelerate electrons to almost the speed of light — they aren’t exactly known for their musical abilities. But if they could create a tune, it would come from the complex combination of variables that keep the electron beam stable as it whizzes around and around the 200m-circumference ring. 

With the Australian summer reflecting off the bitumen of the car park, Henschke recorded the cicada’s song, translated the audio into amplitude data, and then changed the synchrotron “tune” by feeding the recording into the accelerator. The result surprised everyone in the room. “The cicada song resonated with the synchrotron tune, gave it too much energy, and made the beam dump,” said Henschke. In a brief moment of poetic connection, Henschke had managed to bribe the synchrotron into singing the same song as the cicada.

 

 
A synchrotron is a large, circular particle accelerator. An electron beam flies around the inner ring at 99.98% the speed of light. If the beam is kept in “tune”, the beam then moves to the outer storage ring where it passes through magnetic fields to create a very bright light. This light is split off into different wavelengths (i.e infrared, x-rays) and directed down straight beamlines to be used in precise experiments. Copyright © EPSIM 3D/JF Santarelli, Synchrotron Soleil/Wikimedia Commons

A synchrotron is a large, circular particle accelerator. An electron beam flies around the inner ring at 99.98% the speed of light. If the beam is kept in “tune”, the beam then moves to the outer storage ring where it passes through magnetic fields to create a very bright light. This light is split off into different wavelengths (i.e infrared, x-rays) and directed down straight beamlines to be used in precise experiments. Copyright © EPSIM 3D/JF Santarelli, Synchrotron Soleil/Wikimedia Commons

 

It’s been 10 years since Henschke wandered through the halls of the Australian Synchrotron for the first time, his mind boggling at the immensity of the establishment and its operations. The first artist to reside at the Synchrotron, even those in charge couldn’t quite fathom Henschke’s presence. The common query was: “Where’s your paintbrush, your easel?” But at no stage was paint involved. Instead, Henschke chose particle physics as his medium — manipulating data into sound.

When it comes to the seemingly unusual compatibility of music and physics, Henschke, paraphrasing the Nobel Prize-winning physicist Richard Feynman, said: “Physics is creativity in the tightest of straight jackets.” Henschke argues that music and physics are not so dissimilar. “Music is something that we use as a tool to understand the universe, as is high energy particle physics.” While physicists study particles to help comprehend our world, music has the potential to increase people’s understanding of physics itself.

In fact, the link between music and physics, or art and science more broadly, is completely natural. For synchrotron physicist Dr Mark Boland, the increasingly appreciated science-art interface can be seen as “closing a loop that was opened probably a few centuries ago, when there was a separation of art and science and religion.” While Dr Boland believes that art and science “seem to be coming together again quite naturally,” he realises that the intersection may be surprising “for people who are used to the segregated paradigm” that society has embraced for so long. Dr Boland has worked with Henschke on several of his projects at the Synchrotron and, like Henschke, he believes that art and science are just “different aspects of human endeavours that are trying to understand the meaning of it all”.

 
Music is something that we use as a tool to understand the universe, as is high energy particle physics
— Chris Henschke
 

According to Henschke, there are three loose categories of science art: art inspired by science, art that in some way engages with scientific concepts or findings, and art that uses science in its creation.

Henschke’s work with particle physics ensures that he is firmly rooted in the third category. He uses both the data and the equipment from particle accelerators to create art and music. Emotionless physics data can be transformed, literally and figuratively, through a process called sonification. Sonification is the auditory equivalent of data visualisation and it allows scientists to hear anomalies or irregularities in their data that they are unable to see. However, sonification is more than a data exploration tool. Henschke believes that there’s huge potential for sonification to aid in the understanding of complex physics concepts.  

One of his first attempts to combine the two led him to Switzerland, where, for the last few years, he has collaborated with scientists at the European Council for Nuclear Research (CERN) in the Art@CMS project. In collaboration with experimental physicist Wolfgang Adam, Henschke crafted a sound installation based on the high-energy particle collisions occurring within the Large Hadron Collider (LHC) — the world’s largest and most powerful particle accelerator (its 27km rings make the Australian Synchrotron’s paltry 200m circumference seem tiny). Once Adam had mathematically transformed the particle collision data, Henschke was able to compose the various collision events into a 10-minute sound piece called Song of the Muons.

 
 

The fruit of their labour was exhibited during the IEEE Nuclear Science Symposium in October 2016, much to the delight of Professor Barry Barish, a long-time member of the sonification cheer squad who led the LIGO project which first detected gravitational waves. But, it wasn’t just physicists who appreciated the project. The Song of the Muons installation consisted of eight tall oblong speakers positioned in a circle, where each speaker is an individual sound channel. When combined, it allowed people to experience the sound of particle physics.

It starts off as indistinguishable noise — like torrential rain on a tin roof — which is the detection of hadrons and muons as recorded from the LHC. The sound transitions to the second section of the piece, narrowing in on specific events, like listening to individual rain drops. The final section of the sound installation emphasises and extends some particle events even further, drawing them out to the point where time itself is almost stopped. The piece is a genealogy of particle collision events, travelling through different time-scales, from particle to human, of which Henschke said: “nature itself is the source of the composition.”

Closer to home, Henschke recently finished exhibiting a project at the RMIT Gallery in Melbourne inspired by reversing the Synchrotron cicada experiment. Using an old linear particle accelerator from the Australian Synchrotron and a bowl of fruit, the Song of the Phenomena explores the connection between the quantum and macroscopic worlds. Instead of using the accelerator to produce particles (as it once did for medical radiological experiments) the atomic emissions from the fruit are recorded by a Geiger counter, which then modulates the 220Hz sound waves that pass through the accelerator tube. This elaborate method produces a gentle hum, interspersed with clicks and beeps when the accelerator senses electrons and positrons emitted from the high potassium fruit. Nature is again the composer, decaying fruit providing the background music to unsuspecting gallery-goers.

 
Witnessing the decay of fresh fruit, the Song of the Phenomena converts positrons and electrons emitted from the potassium-filled fruit to clicks and beeps. © Mark Ashkenazy (used with permission)

Witnessing the decay of fresh fruit, the Song of the Phenomena converts positrons and electrons emitted from the potassium-filled fruit to clicks and beeps. © Mark Ashkenazy (used with permission)

 

Henschke has long been fascinated by the relationship humans have with machines and devices. The tiniest discoveries in particle physics often rely on gargantuan machinery, with particles such as the Higgs boson only really existing within the machine that created them. A larger ambition of the Song of the Phenomena is to convey this concept that the phenomenon and the apparatus are fundamentally intertwined, that one cannot exist without the other. Without the machinery, you’d just have a bowl of fruit. But without the fruit, you’re simply displaying a feat of engineering, and you don’t get a sense of how it works. Through his sonification projects, Henschke hopes to explain confusing physics concepts like these using art.

High energy particle physics is a complicated field. “It’s important [for scientists] to have an artist’s mindset, in order to interpret what’s going on in a different way. Because often the paradigm in which they are working is quite far removed from basic concepts that the public deal with,” said Dr Boland. When humans interact with technology it is usually with images and sound, so if the visual communication of particle physics isn’t working, then perhaps sonification and music are the future. As Henschke says, “digital media is so malleable, communication has been re-established between art and science practice.” It may not even be that far off, as sonified data from CERN has already made its way onto the stage at a music festival.

Throughout his career working on science art, Henschke has found that sound waves are the common language connecting him with particle physicists. The scientists work with frequencies and amplitudes and so do musicians and composers — just at a much lower energy. Henschke might be one of the first to use the power of music and sound to explore the world of particle physics, but he certainly won’t be the last to strive for this unexpectedly harmonious connection between science and art.

Edited by Tessa Evans and Bryonie Scott