Who first hypothesized the relationship between colors and heat levels?

The correct answer is Sir William Herschel. He is recognized for discovering the infrared radiation spectrum beyond the visible light that is emitted by the sun. In 1800, Herschel conducted an experiment using a prism to separate sunlight into its component colors. He placed thermometers at various points along the color spectrum to measure the temperature of each color. To his surprise, he found that the area just beyond the red color had the highest temperature, indicating a connection between color and heat levels. This groundbreaking work laid the foundation for our understanding of the infrared spectrum and its relationship with thermal energy.

Herschel's discovery highlighted the existence of energy that is not visible to the human eye, paving the way for future research in the fields of optics and radiation. The other figures listed, while significant in their own right, did not specifically explore or establish the link between colors and temperature in the way that Herschel did.