A method for solving the NP complete problem 3SAT and other computational problems which can be reduced to it. Quantum mechanical operations are performed on a finite number of quantum mechanical bits, or “qubits,” in such a way as to concentrate probability in states which solve a given 3SAT problem, provided they exist. Concentration of probability is achieved by generalizing the traditional, reversible model of quantum computation to include irreversible operations mapping one density matrix to another.
Please help me write a proper abstract based on the patent claims. CLAIM: 1. A method for performing irreversible quantum calculations comprising one or more of the steps of: performing a unitary operation; or performing an insertion operation; or performing a deletion operation. 2. The method according to claim 1, which includes the additional steps of: encoding the output of a logical operation, or any property expressible as a logical operation, in the state of a first bit; using the state of said first bit to control the state of one or more other bits; and storing, deleting or further modifying the state of the first bit. 3. A quantum computer, which includes: an algorithm installed on said computer, said algorithm configured for concentrating probability in solution states; a quantum computer function mapping a first density matrix to a second density matrix; and said mapping function having no well-defined inverse. 4. A method for altering the probability distribution for states in a quantum system, which concentrates probability in a state or set of states which satisfies a logical formula. 5. The method of claim 4, in which parameters such as the identity of the decimation gates, the decimation angles corresponding to particular decimation gates, the order of application for different gates, or the number of times that particular decimation gates are applied, are varied between repetitions.