Forests Could Potentially Function as Massive Neutrino Detectors

Physicist Steven Prohira has proposed an intriguing idea of using forests as natural antenna to identify ultra-high-energy neutrinos. He suggests that trees can pick up the radio waves produced by certain interactions of these subatomic particles.

Prohira, an astroparticle physicist, considers this exciting concept a natural solution that might have been overlooked till now. Amy Connolly, a physicist with the Ohio State University who is not associated with the study, echoes similar sentiments.

The challenge lies in detecting neutrinos as they typically require large, sensitive detectors. This is even more applicable for the rarest, highest-energy neutrinos that descend on earth from space.

In the search for these elusive neutrinos, physicists have resorted to constructing inventive detectors in natural locations. Existing examples include the IceCube Neutrino Observatory, which uses a cubic kilometer of Antarctic ice, and the Cubic Kilometre Neutrino Telescope, KM3NeT, which will identify neutrinos interacting in the Mediterranean Sea. Both these vast volume detectors can potentially capture the seldom-found high-energy neutrinos.

In order to explore unusually high-energy neutrinos, scientists plan to identify a specific type of neutrino known as tau neutrino. A tau neutrino when interacts within the earth, it can create a particle called tau lepton. The radio waves created by the shower of charged particles from the escaping tau lepton from earth's crust into its atmosphere could be detected with a detector like the massive GRAND experiment consisting of 200,000 antennas subdivided into 20 arrays across the globe.

Big-scale projects like these led Prohira to mull over utilizing existing antennas. Past research indicated that trees have the capability to access radio waves. Detecting such waves would necessitate affixing a wire in each tree or encasing each tree's trunk with a coil wired to an electronic device able to read the signals.

Despite its potential, the feasibility of this technique is still under question. Further research is required to comprehend the performance of trees for very high frequency radio waves, and investigating their response to the polarization of the radio waves as well as the impact of foliage and seasonal shedding of leaves.

Eric Oberla, a physicist at the University of Chicago, considers the idea inspiring but also acknowledges that replacing manufactured antennas with trees may present more challenges and these issues need to be addressed further.

However, Prohira emphasizes that any effect on the forest should be understood and resolved in a way that respects nature, failing which this idea should be discarded.