conjugate in classical physics, should obey following commutation relation in quantum
QP −PQ =i h/2π (1)
Next year schr
odinger proposed another alternative formalism for quantum mechanics
called "wave mechanics". Wave meachanics is more intuitive than the marix mechanics.
dinger claim his theory was intelligible. Many scientist appreciated this theory. But this
wave theory had problems of its own. Most physicists were slow to accept "matrix mechanics"
because of its abstract nature and its unfamiliar mathematics. Heisenberg was upset about
this development. He admitted that "Matrix mechanics" is not as intuitive as wave mechanics.
To obtain a contradiction-free intelligible interpretation, we still lack some essential feature in
our image of the structure of matter.
The purpose of his 1927 paper was to provide exactly this lacking feature.
In 1927, he publish his paper "On physical content of quantum kinematics and mechanics".
In this paper he proposed uncertainty relations in micro physical systems. His goal was that
matrix mechanics could lay the same claim to intelligibility as wave mechanics. In his view, if
theory is experimentally consistent then we could say that theory is correct.
He adopted an assumption: terms like position of particle have meaning only if one
speciﬁes a suitable experiment by which the "position of a particle" can be measured. He
considered the thought experiment to ﬁnd the "position of the electron" using light(photon).
The shorter the wavelength of light employed, the greater the accuracy will be. But, when we
use the shorter wavelength of light we also have to consider the Compton effect, which will
disturb the momentum of the electron. Heisenberg argues using this thought experiment
that when we known the position more accurately, the momentum becomes less accurate.
The instant of time when the p ositi on is determined, that is, at the instant when the photon
is scattered by the elec tron, the electron undergoes a discontinuous change in momentum.
This change is the greater the smaller the wavelength of the light employed, i.e., the more
exact the determination of the position. At the instant at which the position of the electron is
known, its momentum therefore can be known only up to magnitudes which correspond to
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