منابع مشابه
A Note on Group Matrices1
If numerical values are given to the x then we call the resulting matrix "a" group matrix. This note gives a new characterization of hamiltonian groups by means of group matrices. A matrix A of complex numbers is called normal if AA*=A*A where A* is the transposed, complex conjugate of A. If the matrix also contains indeterminates we introduce formally their conjugates and define normality as b...
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A general proof is given for the equality between group velocity and energy velocity for linear wave propagation in a homogeneous medium with arbitrary spatial and temporal dispersion. In the series of physics “Questions” in the American Journal of Physics, K. M. Awati and T. Howes ask for a general proof of the fact that in linear dispersive wave propagation, energy propagates at the group vel...
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ژورنال
عنوان ژورنال: Bulletin of the American Mathematical Society
سال: 1937
ISSN: 0002-9904
DOI: 10.1090/s0002-9904-1937-06498-6