Hère is a short account of papers published earlier in Russian. We formulate a généralisation of well-known quantization rules by Bohr-Sommerfeld-Einstein-Keller-Maslov by adding terms which describe the tunneling of energy. This enables us to obtain im agi nar y radiational corrections to eigenvalues in the case of open Systems as well as an exponentially small splittings of eigenvalues in Sys...

The theory of quaternions was introduced in the mid nineteenth century, and it found many applications in classical mechanics, quantum mechanics, and the theory of relativity. Quaternions were also later used in aerospace applications and flight simulators, particularly when inertial attitude referencing and related control schemes where employed. However, it is only in the recent past that gra...

Since quaternions have isomorphic representations in matrix form we investigate various well known matrix decompositions for quaternions.

8 Vectors and Quaternions 145 8.1 Vectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145 8.2 Displacement Vectors . . . . . . . . . . . . . . . . . . . . . . . 145 8.3 The Parallelogram Law of Vector Addition . . . . . . . . . . . 146 8.4 The Length of Vectors . . . . . . . . . . . . . . . . . . . . . . 147 8.5 Scalar Multiples of Vectors . . . . . . . . . . . . . . . . . . ....

8 Vectors and Quaternions 40 8.1 Vectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40 8.2 Displacement Vectors . . . . . . . . . . . . . . . . . . . . . . . 40 8.3 The Parallelogram Law of Vector Addition . . . . . . . . . . . 41 8.4 The Length of Vectors . . . . . . . . . . . . . . . . . . . . . . 42 8.5 Scalar Multiples of Vectors . . . . . . . . . . . . . . . . . . . . 43...

Abstract Quaternions are a four-dimensional hypercomplex number system discovered by Hamilton in 1843 and next intensively applied mathematics, modern physics, computer graphics other fields. After the discovery of quaternions, modified quaternions were also defined such way that commutative property multiplication is possible. That called as studied used for example signal processing. In this ...

Over the last decades quaternions have become a crucial and very successful tool for attitude representation in robotics and aerospace. However, there is a major problem that is continuously causing trouble in practice when it comes to exchanging formulas or implementations: there are two quaternion multiplications in common use, Hamilton’s multiplication and its flipped version, which is often...

5 Abstract Algebra 1 5.1 Binary Operations on Sets . . . . . . . . . . . . . . . . . . . . 1 5.2 Commutative Binary Operations . . . . . . . . . . . . . . . . 2 5.3 Associative Binary Operations . . . . . . . . . . . . . . . . . . 2 5.4 Semigroups . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 5.5 The General Associative Law . . . . . . . . . . . . . . . . . . 4 5.6 Identity elements...

In this paper, real matrix representations of split quaternions are examined in terms of the casual character of quaternion. Then, we give De-Moivre’ s formula for real matrices of timelike and spacelike split quaternions, separately. Finally, we state the Euler theorem for real matrices of pure split quaternions.