This paper concerns the Grover algorithm that permits to make amplification of quantum states previously tagged by an Oracle. Grover's algorithm allows searches in an unstructured database of entries, finding a marked element with a quadratic speedup The algorithm requires a predefined number of runs to succeed with probability close to one.
We try to provides a description of the amplitude amplification quantum algorithm mechanism in a very short computational way based on tensor products providing a geometric presentation of the successive system states. All the basis changes are fully described to provide an alternative to the wide spread Grover description based only on matrices and complex tensor computation. Our experiments encompass numerical evaluations of circuit using the Qiskit library of IBM that meet the theoretical considerations