No, joining two photons with wavelengths equivalent to yellow and blue will not result in a single photon with a wavelength corresponding to green. The color perceived by our eyes is determined by the wavelength of light. When yellow light (with a longer wavelength) and blue light (with a shorter wavelength) are combined, they do not directly create green light (with a wavelength between yellow and blue).
The perception of green light typically occurs when light with a specific range of wavelengths, primarily around 495-570 nanometers, stimulates the photoreceptor cells in our eyes. Mixing yellow and blue light does not generate a single photon within this specific range of wavelengths. Instead, the result would be a combination of yellow and blue, which may appear as a different color or a mixture of the two depending on the intensity and proportions of the two colors.
In the realm of light mixing, the perception of color is a complex phenomenon influenced by various factors such as additive color mixing, subtractive color mixing, and human perception. To create green light, it is more common to mix yellow and cyan light (which is closer to blue-green) rather than yellow and blue.