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In 1927, Heisenberg
predicted that:
In this formula,  x refers to the inherent
uncertainty in a measurement of the position, 'x', p refers
to the inherent uncertainty in a measurement of
the momentum, 'p' and 'h' is the by
now familiar Planck constant. |
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Heisenberg made one more fundamental
and long-lasting contribution to the quantum world – the
uncertainty principle. He showed that quantum mechanics
implied that there was a fundamental limitation on the accuracy
to which pairs of variables, such as (position and momentum)
and (energy and time) could be determined. This flew in
the face of the traditional wisdom of determinism carried
over from Laplace's times.
If a 'large' object with a mass of, say, 1g has its position
measured to an accuracy of 1 , then the uncertainty on
the object's velocity is a minute 10-25 m/s.
The uncertainty principle simply does not concern us in
everyday life. In the quantum world the story is completely
different. If we try to localize an electron within an
atom of diameter 10-10 m the resulting uncertainty
on its velocity is 106 m/s! |
The Nobel Prize in Physics 1932 -
Werner Karl Heisenberg »
