While Daniel Nocera is trying to mimic the photosynthetic activity of plants, scientists from the University of Toronto discover how “simple” plants like marine algae can use quantum mechanics principles they have been using for billions of years.
Professor Greg Scholes, the lead author of the study published recently in Nature, says: “There’s been a lot of excitement and speculation that nature may be using quantum mechanical practices. Our latest experiments show that normally functioning biological systems have the capacity to use quantum mechanics in order to optimize a process as essential to their survival as photosynthesis.”
The plants’ natural solar cells, known as “reaction centres” use some special protein called “light harvesting complexes” that capture sunlight and funnel the energy into them. Scholes and his team of chemists isolated the complexes in charge of harvesting the light from two species of marine algae and studied their behavior under natural temperature conditions and using a complex laser experiment known as two-dimensional electronic spectroscopy.
They stimulated the proteins with femtosecond-long laser impulses, simulating normal light. Prof. Schole says: “This enabled us to monitor the subsequent processes, including the movement of energy between special molecules bound in the protein, against a stop-clock. We were astonished to find clear evidence of long-lived quantum mechanical states involved in moving the energy. Our result suggests that the energy of absorbed light resides in two places at once — a quantum superposition state, or coherence – and such a state lies at the heart of quantum mechanical theory.”
“This and other recent discoveries have captured the attention of researchers for several reasons,” says Scholes. “First, it means that quantum mechanical probability laws can prevail over the classical laws of kinetics in this complex biological system, even at normal temperatures. The energy can thereby flow efficiently by — counter intuitively — traversing several alternative paths through the antenna proteins simultaneously. It also raises some other potentially fascinating questions, such as, have these organisms developed quantum-mechanical strategies for light-harvesting to gain an evolutionary advantage? It suggests that algae knew about quantum mechanics nearly two billion years before humans,” says Scholes.
Finding out that plants can use quantum mechanics only tells me there would be no wonder when we could one day find out our own bodies and surrounding plants use these principles, and that the energy actually obeys a different set of rules rather than the particular ones we used to know. This is a major discovery, in my opinion, anyway.
And all we ever thought of was getting those poor, technologically advanced algae to produce more diesel for our cars…