Duality of matter

Erwin Schrodinger (1887-1961 Nobel Prize for physics 1932) transferred the concept of wave-particle duality of matter developed by L. V. de Broglie for electrons to the whole atom and thus developed wave mechanics. The Schrodinger equation allows a description of orbitals as the probability of the location of the electrons. Wave mechanics represented a significant development, but were subsequently shown to be insufficient. 

The fact that atoms, electrons, nuclei, and other forms of matter have some properties that lead us to describe them as particles and other properties that we associate with waves is referred to as the wave-particle duality of matter. This wave-particle duality is hard to understand but it is a fact—a part of the world in which we live. 

Describe the wave-particle duality of matter and energy and the theories and experiments that led to it (particle wavelength, electron diffraction, photon momentum, uncertainty principle) ( 7.3) (SP 7.3) (EPs 7.27-7.34)... 

The word radiation was used until about 1900 to describe electromagnetic waves. Around the turn of the century, electrons. X-rays, and natural radioactivity were discovered and were also included under the umbrella of the term radiation. The newly discovered radiation showed characteristics of particles, in contrast to the electromagnetic radiation, which was treated as a wave. In the 1920s, DeBroglie developed his theory of the duality of matter, which was soon afterward proved correct by electron diffraction experiments, and the distinction between particles and waves ceased to be important. Today, radiation refers to the whole electromagnetic spectrum as well as to all the atomic and subatomic particles that have been discovered. 

The early alchemists and natural philosophers believed in the duality of matter —sun and moon male and female sulfur (fixed) and mercury (volatile). When Davy electrolyzed pure potash (KOH) and produced a volatile (female) spirit (oxygen) at the positive pole and an explosive, fixed (male) matter (potassium) at the negative pole, this would have been intuitively obvious to them. 

Thus electrons behave in some respects like particles and in other respects like waves. We are faced with the apparently contradictory wave-particle duality of matter (and of light). How can an electron be both a particle, which is a localized entity, and a wave, which is nonlocalized The qpswer is that an electron is neither a wave nor a particle, but something else. An accurate pictorial description of an electron s behavior is impossible using the wave or particle concept of classical physics. Hie concepts of classical physics have been developed from experience in the macroscopic world and do not properly describe the microscopic world. Evolution has shaped the human brain to allow it to understand and deal effectively with macroscopic phenomena. The human nervous system was not developed to deal with phenomena at the atomic and molecular level, so it is not surprising if we cannot fully understand such phenomena. 

In other words, there is a duality of matter and energy. Whether the particle-like or the wavelike character of mat-ter/energy is dominant depends on the experiment. In fact, the experiment itself interacts with the matter/energy and defines some aspect of the system at the cost of indefiniteness of some other aspect. This uncertainty principle was made precise by Heisenberg who showed that even under the most ideal circumstances... 

The Wave-Particle Duality of Matter—The de Broglie Hypothesis... 

The uncertainty principle, an important relation that is a consequence of quantum mechanics, was discovered by the German physicist Werner Heisenberg (born 1901) in 1927. Heisenberg showed that as a result of the wave-particle duality of matter it is impossible to carry out simultaneously a precise determination of the position of a particle and of its velocity. He also showed that it is impossible to determine exactly the energy of a system at an instant of time. 

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