# Biophotons: A Hard Problem  
[PERSON]  
1 Laboratori Nazionali di Frascati, Istituto Nazionale di Fisica Nucleare, Via E. Fermi 40, 00044 Frascati, Italy; [EMAIL_ADDRESS] (L.D.P. ); [EMAIL_ADDRESS] (A.S.); [EMAIL_ADDRESS] (A.C.); [PERSON]C.C. )1  
[PERSON]  
2 Dipartimento di Ingegneria Industriale, Universita di \"Tor Vergata\", Via del Politecnico, 00133 Roma, Italy; [EMAIL_ADDRESS] (R.F. ); [PERSON]DRESS] (F.D.M. )2  
[PERSON]  
3 Dipartimento di Fisica, Universita di \"Tor Vergata\", Via della Ricerca Scientifica, 00133 Roma, Italy; [EMAIL_ADDRESS] (R.  
noted that the contribution of the thermal part, calculated with the Planck distribution in the visible energy range and at room temperature is practically zero [3]. Furthermore, the presence of any type of stress, from chemical to a change in temperature, typically induces an increase in emission, which can reach up to a few orders of magnitude greater than the nonstressed baseline, followed by a decrease, which follows a nonexponential power law, up to normal values [1; 2]. In the 1920s, the Russian biologist [PERSON]. [PERSON] [4], observing the growth rate of onion plants, hypothesized the existence of an electromagnetic field responsible for the regulation of cellular growth in living systems, capable of influencing the mitotic activity of the surrounding tissues. He called this weak emission \"mitogenetic radiation\". Despite the confirmation of his results (see the article by [PERSON] and [PERSON] [5]), the scientific community completely ignored [PERSON]'s results; therefore, his work faded into the background. Only thirty years later, [PERSON] and [PERSON] [6; 7] carried out the first measurement of electromagnetic emission from living organisms through the use of the first photon detectors used in single-photon counting mode. This work again fell into oblivion; only thirty years later, [PERSON] et al. [2] began a large experimental/theoretical research project to understand the origin and significance of biophoton emission in detail. Nowadays, there are no longer any doubts about the experimental evidence of biophotonic emissions; however, questions related to their generation and the role they have in biological processes remain open. There are currently several hypotheses [1; 2] that try to explain this surprising phenomenon that is typical of living beings. These can essentially be divided into two categories: in the first, the emission derives from the random processes of the radiative decay of the molecules previously excited by metabolic processes, while in the second, the theories are based on the existence of a coherent electromagnetic field inside the cells that in some way generates the observed biophotonic emission. Both theories predict that any type of perturbation generated by nonspecific stress gives rise to an increase in emission, as observed experimentally. The two hypotheses are not mutually exclusive, and the emission could have a dual origin. There is also clear experimental evidence that biophotonic emission carries some type of biological information [8; 9; 10; 11]; for example, the emitted radiation can increase the rate of cell division by up to 30% in similar organisms, which is the so-called mitogenetic effect [12; 11; 13]. Recently, biophotons are also revealing their ability to be used in noninvasive methods for research in biology from applications in toxicology [14] to human health monitoring [15] as well as identification and treatment of diseases, especially cancer [16]. In this short review, we present the results we obtained by following the emission of biophotons from various types of seeds during the germination process. Our experimental apparatus essentially consists of a black PVC dark chamber appropriately made to avoid any contamination from external light and a photomultiplier that works as a single-photon count device. The experimental data consist of the number of photons that arrived at the sensitive part of the photomultiplier in a well-defined time window (1 sec.