If light waves were infinitely long, it would mean that their wavelength would be infinitely large, approaching an infinite distance between successive peaks or troughs of the wave. This scenario would have several consequences:
No Perception of Light: Our eyes are sensitive to a narrow range of wavelengths known as the visible spectrum. If light waves were infinitely long, they would no longer fall within this range, and we would not be able to perceive them as visible light. We would not be able to see anything since there would be no light for our eyes to detect.
No Transmission of Information: Light is an electromagnetic wave, and its ability to transmit information relies on its wavelength. In everyday applications, we use light waves for communication, such as through fiber optics or wireless technologies. If light waves were infinitely long, their inability to encode distinct wavelengths would make it impossible to carry information through them efficiently. Communication systems as we know them would not function.
Interference with Matter: Light interacts with matter based on its wavelength. When light interacts with objects or passes through different materials, its wavelength determines the phenomena like absorption, reflection, or refraction that occur. If light waves were infinitely long, they would not interact with most matter in the same way as shorter wavelengths. The interactions between light and matter would likely be significantly altered or even nonexistent.
Changes in Energy and Momentum: Light waves carry energy and momentum. If light waves were infinitely long, their energy and momentum would be spread out over an infinite distance. This would have profound implications for the laws of physics and the conservation of energy and momentum. The behavior of light and its effects on the surrounding environment would be drastically different from what we observe with finite wavelengths.
It's important to note that in reality, light waves have a finite range of wavelengths, and the properties of light that we observe and study are based on these finite wavelengths.