back in time to 1930s Germany. You encounter a follower of \"Deutsche Physik\" (
ID: 1544030 • Letter: B
Question
back in time to 1930s Germany. You encounter a follower of "Deutsche Physik" (lit. "German physics," which suppressed contributions to science that were made by Jewish physicists, such as Bohr and Einstein). Convince this person that classical mechanics is insufficient, and quantum mechanics is necessary, to properly describe the natural world. Use at least three experimental results to back up your argument. Assume your audience can follow a scientific argument, but needs you to define your scientific jargon. Type your response (you may email it to me atExplanation / Answer
The theory of relativity describes the behaviour of large everyday objects in the world around us. However this theory alone is not enough to describe things at a very small scale. At the level of atoms and sub-atomic particles objects behave very differently and quantum theory is an attempt to describe the behaviour of matter and energy at this sub atomic scale.
Experiments with particles in the early 1900s provided some very confusing results. One of the conclusions drawn from these experiments is that small particles such as photons and electrons can behave either like a wave or like a particle under different circumstances.
Particles can be subject to interference and diffraction like light waves. However the act of observing a particle causes it to be detected as a particle in a specific location and not a wave.
The implications of quantum theory are wide ranging. Quantum mechanics has explained the structure of the atom and the structure of the nucleus. Without knowing the structure of the atom, most of the physics and chemistry that we know today wouldn't have been possible. Quantum theory predicted the existence of antimatter, and explains radioactivity.
Many applications resulting from quantum theory are in use today, and its applications in the future are potentially infinite.
The theory of lasers was first outlined in 1917 in a paper "On the Quantum Theory of Radiation" by Albert Einstein, and the first functional lasers were built in the 1950s. Quantum theory also explains the photoelectric effect, whereby electons are emitted from matter as a result of absorbing energy from light - this occurs in human vision, and has practical applications in digital cameras. Quantum physics is also used in night vision goggles and 'scanning tunnelling microscopes' (which create images of surfaces where individual atoms can be seen).
Three revolutionary principles are:
Quantized properties: Certain properties, such as position, speed and color, can sometimes only occur in specific, set amounts, much like a dial that "clicks" from number to number. This challenged a fundamental assumption of classical mechanics, which said that such properties should exist on a smooth, continuous spectrum. To describe the idea that some properties "clicked" like a dial with specific settings, scientists coined the word "quantized."
Particles of light: Light can sometimes behave as a particle. This was initially met with harsh criticism, as it ran contrary to 200 years of experiments showing that light behaved as a wave; much like ripples on the surface of a calm lake. Light behaves similarly in that it bounces off walls and bends around corners, and that the crests and troughs of the wave can add up or cancel out. Added wave crests result in brighter light, while waves that cancel out produce darkness. A light source can be thought of as a ball on a stick being rhythmically dipped in the center of a lake. The color emitted corresponds to the distance between the crests, which is determined by the speed of the ball's rhythm.
Waves of matter: Matter can also behave as a wave. This ran counter to the roughly 30 years of experiments showing that matter (such as electrons) exists as particles.
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