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What does it mean to say that a quantum computer is universal?
quantum Turing machine
A quantum Turing machine (QTM) or universal quantum computer is an abstract machine used to model the effects of a quantum computer. It provides a simple model that captures all of the power of quantum computation—that is, any quantum algorithm can be expressed formally as a particular quantum Turing machine.
Can a quantum computer create a universe?
Lloyd also postulates that the Universe can be fully simulated using a quantum computer; however, in the absence of a theory of quantum gravity, such a simulation is not yet possible. “Particles not only collide, they compute.”…Programming the Universe.
| Softcover edition | |
|---|---|
| Author | Seth Lloyd |
| Dewey Decimal | 530.12 22 |
| LC Class | QC174.12 .L57 2006 |
Are there any universal gates in a quantum computer?
There also exists a single two-qubit gate sufficient for universality, given it can be applied to any pairs of qubits on a circuit of width . Another set of universal quantum gates consists of the Ising gate and the phase-shift gate. These are the set of gates natively available in some trapped-ion quantum computers.
How are qubits represented in a quantum logic gate?
Quantum logic gates are represented by unitary matrices. The number of qubits in the input and output of the gate must be equal; a gate which acts on n {displaystyle n} qubits is represented by a 2 n × 2 n {displaystyle 2^{n}times 2^{n}} unitary matrix.
What are the building blocks of a quantum circuit?
In quantum computing and specifically the quantum circuit model of computation, a quantum logic gate (or simply quantum gate) is a basic quantum circuit operating on a small number of qubits. They are the building blocks of quantum circuits, like classical logic gates are for conventional digital circuits. Unlike…
How are quantum gates described as unitary operators?
Quantum gates are unitary operators, and are described as unitary matrices relative to some basis. Usually we use the computational basis, which unless we compare it with something, just means that we for a d -level quantum system (such as a qubit, or a quantum register) have labeled the orthogonal basis vectors