Quantum theory, although of tremendous scientific value, has nevertheless prompted debate among physicists. The debate arose because quantum theory addresses the peculiar properties of minute objects such as photons and electrons. While one type of experiment shows that these objects behave like particles, with well-defined trajectories through space, another demonstrates that, on the contrary, they behave waves, their peaks and troughs producing characteristic "interference" effects. However, scientists have failed to devise an experiment to demonstrate both behaviors simultaneously.
In the 1920s, two alternate interpretations of quantum theory attempted to resolve this apparently contradictory wave-particle duality. Physicist Niels Bohr argued that wave-particle properties are not contradictory, but complementary. Contrary to our intuition that an object continues to exist in some determined form even though we cannot perceive it, he concluded that the physical of a quantum object is actually undetermined before the object is observed via experiment.
Physicist Werner Heisenberg's "uncertainty principle," by contrast, postulated that we cannot precisely determine two complementary properties, such as position and momentum, of a quantum object simultaneously: if we measure an object's position with absolute certainty, then there is an infinite uncertainty in its momentum, and vice versa. He concluded that although we are limited in our ability to measure objects at the atomic and subatomic levels, their position and momentum are nonetheless defined all along.
A. A thesis is introduced and then amended. 无涉及
B. Arguments are presented, weighed, and then reconciled. 无涉及
C. A problem is described and different interpretations intended to resolve the problem are
D. Hypotheses are analyzed, their premises are refuted, and alternatives are suggested to replace
the hypotheses. 无涉及
E. A theory is advanced, opposing evidence is considered, and the theory is abandoned. 无涉及
第一段最后一句However, scientists have failed to devise an experiment to demonstrate both behaviors simultaneously. 第二段第一句In the 1920s, two alternate interpretations of quantum theory attempted to resolve this apparently contradictory wave-particle duality However, scientists have failed to devise an experiment to demonstrate both behaviors simultaneously.=A problem two alternate interpretations=different interpretations