The discussion centers on calculating the wavelength of light emitted during an electron transition from n=3 to n=1 in a hydrogen atom. Participants emphasize using the energy formula E=hc/λ, where E is the energy difference between the two states, h is Planck's constant, c is the speed of light, and λ is the wavelength. One user initially calculated a wavelength of 8.1 x 10^-6 m and sought confirmation of its accuracy. Others suggested checking textbooks and provided a link to HyperPhysics for additional resources on electron transitions, indicating that the necessary formulas and explanations are readily available in standard physics texts.