Applications Of Modern Physics !!top!! 〈PRO〉

Today, the applications of modern physics are so deeply embedded in our infrastructure that they have become invisible. We don't "see" quantum mechanics when we turn on a light (LEDs are quantum devices); we don't "feel" relativity when we board a plane (the altimeter compensates for gravitational time dilation).

Solar cells are essentially large-area semiconductor diodes. When a photon from the sun strikes silicon, it transfers its energy to an electron (the photoelectric effect , explained by Einstein in 1905). That electron jumps the "band gap," leaving a hole. The internal electric field of the p-n junction drives the electron through a circuit, creating electricity. Modern efficiency records (over 47% for multi-junction cells) come from stacking different semiconductors with varying band gaps to capture different wavelengths of sunlight. Applications Of Modern Physics