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Wavelike behaviour

It is just not possible—in principle—to measure position and momentum with absolute certainty. If we try to determine whether an electron is a wave or a particle, then we find that an experiment which forces the electron to reveal its particle character (for example, one using a very short wavelength microscope) suppresses its wave character as Ap and hence A are large. Alternately, when an experiment focuses on the electron s wavelike behaviour, as in electron diffraction, A is small, but there is a correspondingly large uncertainty in the position of any given electron within the incident beam. [Pg.28]

The development of the quantum theory in the early twentieth century allowed predictions to be made relating to the properties and behaviour of matter and light. The electrons in matter have both wavelike and particle-like properties, and quantum theory shows that the energy of matter is quantised that is, only certain specific energies are allowed. [Pg.2]

Erwin Schrodinger developed an equation to describe the electron in the hydrogen atom as having both wavelike and particle-like behaviour. Solution of the Schrodinger wave equation by application of the so-called quantum mechanics or wave mechanics shows that electronic energy levels within atoms are quantised that is, only certain specific electronic energy levels are allowed. [Pg.6]

In 1926, Erwin Schrodinger used de Broglie s idea that matter has wavelike properties. Schrodinger proposed what is now known as the quantum mechanical model of the atom. In this new model, he abandoned the notion of the electron as a small particle orbiting the nucleus. Instead, he took into account the particle s wavelike properties, and described the behaviour of electrons in terms of wave functions. [Pg.657]

Experimentally, the mechanism of intercellular communication by cAMP pulses in the course of D. discoideum aggregation is characterized by its periodicity. The latter is reflected by the wavelike movement of amoebae towards the aggregation centres, as a result of the periodic pulses of cAMP that the latter emit at regular intervals (Durston, 1974a). The periodic behaviour of the model based on receptor desensitization accounts for the periodic secretion of cAMP by aggregation centres, whereas excitable behaviour accounts for the relay of cAMP pulses by cells that amplify the suprathreshold signals emitted by the centres. [Pg.262]


See other pages where Wavelike behaviour is mentioned: [Pg.5]    [Pg.5]    [Pg.318]    [Pg.5]    [Pg.5]    [Pg.318]    [Pg.1197]    [Pg.97]    [Pg.1197]    [Pg.19]    [Pg.263]    [Pg.54]    [Pg.236]    [Pg.680]    [Pg.681]   
See also in sourсe #XX -- [ Pg.196 ]




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