Another Werner Heisenberg Essay

Rather than the classical idea of the position and

Info icon This preview shows pages 3–5. Sign up to view the full content.

Rather than the classical idea of the position and the motion, or momentum, of the electron at each instant in time, Heisenberg introduced his square arrays or matrices, which depict the electron as existing simultaneously in all possible Bohr orbits. After Heisenberg's discovery, the classical concept of the electron as a particle was no longer justifiable. Heisenberg was led to these revolutionary ideas by his insistence on utilizing only those quantities in a theory that are directly observable. Since the orbit of an electron is not observable, it can have no place in a theory. Only the spectral lines are observed, and, since these involve pairs of orbits, all quantities that are used to describe the electron inside the atom should be associated with such pairs. Such thinking led to Heisenberg's matrices. One of the important features of matrices is that it is not commutative. If the array representing the position of an electron is q and an array representing its momentum is p, then the product pq is not the same as the product qp. This showed Heisenberg that the uncertainty relationship is purely an algebraic consequence of his matrix theory. If you picture the product pq as representing a measurement of the position of the electron followed by a measurement of its momentum; qp, on the other hand, represents the measurement of the momentum of a particle followed by at the measurement of its position. That these two sets of measurements give different results simply means that the measurement of the momentum of a particle destroys our knowledge of its position, and vice versa. It follows that it is impossible to obtain or to have precise knowledge of the position and the momentum of a particle simultaneously; this is the essence of the uncertainty principle. Its significance for the structure of the atom is that we have no way of
Image of page 3

Info icon This preview has intentionally blurred sections. Sign up to view the full version.

determining the orbit of an electron inside the atom observationally. As Heisenberg pointed out in his analysis of the Copenhagen interpretation of quantum theory, an electron can be observed inside an atom only with a gamma-ray microscope which, because of the short wavelength of gamma rays, has a high resolving power. This microscope shows us where the electron is at any moment, but at least one gamma-ray photon must be reflected from the electron.
Image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.
  • Spring '10
  • white
  • Heisenberg, Werner Heisenberg, Werner Karl Heisenberg

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern