Biophotons: A Hard Problem
About a hundred years ago the Russian biologist A. Gurwitsch, based on his experiments with onion plants by measuring their growth rate, made the hypothesis that plants emitted a weak electromagnetic field which somehow influenced cell growth. This interesting observation remained fundamentally ignored by the scientific community and only in the 1950s the electromagnetic emission from some plants was measured using a photomultiplier used in single counting mode. Later, in the 80s several groups in the world started some extensive work to understand the origin and role of this ultra-weak emission, hereby called biophotons, coming from living organisms. Biophotons are an endogenous very small production of photons in the visible energy range in and from cells and organism, and this emission is characteristic of alive organisms. Today there is no doubt that biophotons really exist, this emission has in fact been measured by many groups and on many different living organisms, from humans to bacteria. On the contrary, the origin of biophotons and whether organisms use them in some way to exchange information is not yet well known; no model proposed since now is really capable of reproducing and interpreting the great variety of experimental data coming from the many different living systems measured so far. In this brief review we present our experimental work on biophotons coming from germinating seeds, the main experimental results and some methods we are using to analyze the data in order to open the door for interpretative models of this phenomenon and clarifying its function in the regulation and communication between cells and living organisms. We also discuss some ideas on how to increase the signal-to-noise ratio of the measured signal to have new experimental possibilities that allow the measurement and the characterization of currently unmeasurable quantities.