What do ants have to do with quantum electrodynamics?
The story of how ant-watching led to a Nobel Prize in Physics…
A fine man of physics
Ever since I was little, I’ve been fascinated by ants – possibly more than any other creature. I would follow them around everywhere and observe their behaviour for hours on end. Recently, I’ve fallen back in love with ants by discovering YouTube channels dedicated to ant-keeping.
It was to my surprise then (and delight) that Richard Feynman, legendary Nobel Prize-winning theoretical physicist, shared a deep intrigue for ants.
I’m currently reading his autobiography “Surely you’re joking, Mr Feynman!” in which he reminisces over various adventures in life. He dedicates a chapter to recount his stories about watching ants.
As an adult, Feynman would watch ants foraging in his house. In his book, he fondly describes the time he investigated how ants’ trails looked so straight. His plan was simple: leave a sugar cube out and wait for ants to come by so that he could trace their trails with different coloured pencils.
What he noticed was that the paths of the initial exploring ants was not straight, but wavy! Then subsequent ants following the trail would incrementally straighten out the path. Being a physicist, he noticed striking similarities in the paths of foraging ants and the path of a particle of light.
This observation inspired many questions like “How do objects with no sense of ‘straightness’ travel in straight lines?”. Feynman’s interpretation of the quantum ‘paths’ of an object was developed after seeing the ants’ foraging patterns, and is our current understanding of how quantum objects behave.
Richard Feynman’s work in the field of quantum electrodynamics would eventually lead him to a Nobel Prize in Physics in 1965.
The mathematics of Feynman’s findings are completely out of my depth, but if you’re feeling brave then here’s a blog post going into more detail.
What is this? Physics for ants?
Not only have these little creatures inspired some amazing work in physics, they regularly exploit the physics of their own biology. The best example of this is the red fire ant.
Having evolved from the floodplains of South America, these ants have developed an interesting tactic to keep their colony alive in case of a flood. By linking their bodies together, they take advantage of their water-repellent properties to form an emergency life raft!
Physicists consider a mass of ants to be a material – one that can behave as both a solid and a liquid. If you disturb a clump of ants like the ones pictured above, the ants will actually repair their structure. If you force them through a funnel, they will drip out like honey! No other material has these properties!
The bizarre properties of ants is being emulated by roboticists who think that modular robots are the way to go. Imagine masses of tiny robots forming large structures and are capable self-repair. It goes to show you that you can always look to nature for inspiration.
I hope you can see why I really love ants. They’ve indirectly made contributions to the field of quantum electrodynamics and are still puzzling physicists today with their wacky biology.