Questions tagged [oracles]
An oracle is a "black box" operation (function) that is used as an input to an another algorithm (for example Deutch-Jozsa, Grover etc.). A parameter or feature of the Oracle is infered by the algorithm.
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How to construct an oracle and flips the phase of the solution bit strings?
I am trying to solve the boolean problem (x1 or x2) and (~x1 or ~x2 or x3) using Grover's algorithm. The only measured bits are q0, q1, and q2. This is my oracle:
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Grover's Algorithm oracle for finding an 8-bit key
I've been trying around different things with Grover's algorithm, and would want to experiment a practical scenario with it by building an oracle to find an 8-bit key.
Very shortly explained, my ...
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Does applying a balanced function on a single qubit out of n and applying constant function on the remaining n-1 implements overall BALANCED function?
I am studying Deutsch-Josza Algorithm. Here's what I get for 2-qubit case.
$$
\begin{aligned}
|\psi_0\rangle &= |0\rangle\otimes |0\rangle \\
|\psi_1\rangle & = H|0\rangle \otimes H|0\rangle \\...
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Is there an efficient way to implement quantum read-only memory (QROM)?
I'm looking to understand how quantum read-only memory (QROM) is implemented, specifically how classical data can be loaded into ancilla qubits using controlled operations.
From what I've read so far, ...
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One Shot Signature Security Proof
I was studying the paper (e-print) "One Shot Signatures and Applications to Hybrid Quantum/Classical Authentication." In it, the authors define "equivocal hashing" and provide a ...
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Coding Oracle for Grover's Algorithm - Qiskit
I am looking to create an oracle that marks the solution states by checking the arrays entries(1 column and many rows) with a threshold. If the value in the array is greater then the threshold the ...
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How to Implement an Oracle in Qiskit or Cirq that Maps f(a, b) = (x^a)*(y^b)?
I'm trying to implement an oracle in Qiskit or Cirq for a function f that maps Z x Z to a group A. The function is defined as f(a, b) = (x^a) * (y^b).
a and b are the first two quantum registers,...
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Doubt on construction of phase oracle in Grover's Algorithm
In the above question from de Wolf's lecture notes, I'm facing difficulties in constructing the oracle. I'm unable to understand how to use the boolean oracle to construct a phase oracle. Any help ...
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Construction of $f(x) = x \pmod 2$ as an oracle function
I'm trying to conceptualise how one would implement an oracle function of f(x) = x in the context of the Deutsch-Josza Algorithm. So far I understand the basic idea of implementing trivial constant ...
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Implementation of the Grover's oracle in a real life use case
Imagine a database of DNA fingerprints, each one characteristic of only one person. You
are given a DNA trace and asked to find the person to which it belongs. There is no way
(to my knowledge !) to ...
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Does this quantum circuit reproduce the oracle in Deutsch's algorithm?
This seems to me a fine quantum oracle for the balanced one bit function $f(x)=x$, but putting it in Deutsch's algorithm circuit will give the result $|0\rangle$, i.e. the function is evaluated as ...
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How can you decide the value of $f$ on a given string using its phase shift oracle?
Let $f: \{0,1\}^n \rightarrow \{0,1\}$ be a Boolean function and say we are given a phase shift oracle $O_f^{\pm}$ which performs $|x\rangle \mapsto (-1)^{f(x)}|x\rangle$. Is there any way we can ...
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How to construct the HHL oracle circuit when the entries of $A$ are described by a polynomial?
Among other assumptions, HHL's algorithm assumes that the entries of the coefficient matrix $A$ (where $Ax=b$ is the linear system to be solved) can be realized by means of an oracle circuit $U_A$. ...
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QMA-QCMA oracle with quantum gates
While reading the QMA-QCMA paper by Aaronson and Kuperberg I wondered how their result extends to quantum circuits.
Suppose you have an oracle $O$ such that $O\left|\psi\right>=-\left|\psi\right>...
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