In the special case 'A' has only discrete spectrum, the possible outcomes of measuring 'A' are its eigenvalues.

A physical quantity is said to have a discrete spectrum if it takes only distinct values, with positive gaps between one value and the next.

In the case of gravity, the operators representing the area and the volume of each surface or space region have discrete spectrum.

This was followed shortly by a proof of the analogous results for measure preserving transformations with generalized discrete spectrum.

In particular, certain physical observables, such as the area, have a discrete spectrum.

The energy eigenvalues from this equation form a discrete spectrum of values, so mathematically energy must be quantized.

Given this discrete spectrum, the algorithm is initialized by:

The study of inelastic scattering then asks how discrete and continuous spectra are mixed together.

On this space, it has a discrete, non-unitary, decaying spectrum.

Suppose the Hamiltonian H of interest is a self adjoint operator with only discrete spectrum.