Electromagnetic radiation wave-particle duality

You can appreciate why scientists were puzzled The results of some experiments (the photoelectric effect) compelled them to the view that electromagnetic radiation is particlelike. The results of other experiments (diffraction) compelled them equally firmly to the view that electromagnetic radiation is wavelike. Thus we are brought to the heart of modern physics. Experiments oblige us to accept the wave-particle duality of electromagnetic radiation, in which the concepts of waves and particles blend together. In the wave model, the intensity of the radiation is proportional to the square of the amplitude of the wave. In the particle model, intensity is proportional to the number of photons present at each instant. 

This, plus the quantization of the normal modes of vibration of the electromagnetic radiation field (just demonstrated), form, together, the quantum-mechanical basis for the wave-particle duality A wave can become a particle, and vice versa, but you can never make a simultaneous experiment to test both the wave and the particle nature of the same system. 

Fig. 2.6 Experiments verifying the wave/particle duality of electromagnetic radiation, and the bridge between corpuscular and wave physics relation of the momentum p to the wavelength X.

Quantum of radiation) An elementary particle of electromagnetic energy in the sense of the wave-particle duality. 

The nature of electromagnetic radiation baffled scientists for many years. At times light appears to behave like a wave at other times it behaves as though it were composed of small particles. While we now understand the wave-particle duality of all matter, including electromagnetic radiation, in terms of quantum mechanics, it is still convenient to consider electromagnetic radiation as having the properties of waves in many cases. 

Schrodinger and de Broglie suggested a "wave-particle duality" for small particles—that is, if electromagnetic radiation showed some particle-like properties, then perhaps small particles might exhibit some wave-like properties. Explain. How does the wave mechanical picture of the atom fundamentally differ from the Bohr model How do wave mechanical orbitals differ from Bohr s orbits What does it mean to say that an orbital represents a probability map for an electron ... 

Which fundamental particles are important in chemistry The nature of electromagnetic radiation The photoelectric effect Wave-particle duality... 

Wave-particle duality was discussed in terms of the wave-like and particulate properties of both electromagnetic radiation and electrons. 

The wave model fails to account for phenomena associated with the absorption and emission of radiant energy. To understand these processes, it is necessary to invoke a particle model in which electromagnetic radiation is viewed as a stream of discrete particles, or wave packets, of energy called photons. The energy of a photon is proportional to the frequency of the radiation. These dual views of radiation as particles and as waves are not mutually exclusive but, rather, complementary. Indeed, the wave-particle duality is found to apply to the behavior of streams of electrons, protons, and other elementary particles and is completely rationalized by wave mechanics. 

An X-ray fluorescence spectrometer needs to resolve the different peaks, identify them and measure their area to quantify the data. There are two forms of X-ray spectrometers (Fig. 5.5), which differ in the way in which they characterize the secondary radiation - wavelength dispersive (WD), which measures the wavelength, and energy dispersive (ED), which measures the energy of the fluorescent X-ray (an illustration of the particle-wave duality nature of electromagnetic radiation, described in Section 12.2). 

So we see that across the various hierarchical levels between the physics and chemistry of neurons of the brain and the human mind, it is very difficult if not impossible to attribute clear-cut principles of causation. Causation seems to enter the picture at each and every hierarchical level, and is not wholly reducible to prior causation at another level of organization. About all that can be said with confidence at this point is that brain and mind facilitate and reflect each other, like the valley and the river, but in no logical sense do they cause each other that they are parallel processes, and for an analogue of this seemingly paradoxical statement I would compare the mind-brain duality to particle-wave duality in quantum mechanics. The wave attributes of electromagnetic radiation do not cause the particle attributes, nor vice versa. The... 

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 wave function is used to describe electrons around the nucleus of an atom because electrons can be difBacted. Diffiaction is usually associated with electromagnetic radiation (light), but electrons also produce diffraction patterns. This means that electrons also exhibit particle-wave duality. In some instances, electrons are treated as particles in other instances, they are treated as waves. 

The speed of electromagnetic radiation represents how fast energy is transferred through space, whereas the frequency of the radiation tells us how many waves pass a given point per time unit. 8. wave-particle nature (duality)... 

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