Questions tagged [grovers-algorithm]
Grover's search algorithm is an algorithm that can perform a search in the order of square root of the input size. This is a provable speed up over the best classical algorithm, which requires a time of order N to perform a search.
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Is it possible to entangle two qubits (by means of Grover techniques)?
Given two separate states, I'd like to entangle them to a specific configuration.
Example 1:
$$|+\rangle \otimes |+\rangle \rightarrow \frac{1}{\sqrt{2}}(|00\rangle + |11\rangle)$$
Example 2:
$$(a_1|0\...
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Simplifying the Grover's algorithm
I am learning quantum computing as a beginner and have a question about the Grover’s algorithm (perhaps a naive question). I understand that the key of the Grover’s algorithm is to iteratively use a ...
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Grover's algorithm number of iterations
I am trying to understand Grover's algorithm without much of a background in quantum. I believe I understood the main parts to be:
The quantum state is initialized to represent all $n$ possible ...
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Is Grover's Algorithm useless?
If I know what oracle to implement, I know what is the state that I am searching for, so why should I use this algorithm?
I mean, if my quantum control system knows how to implement the oracle, it ...
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Grover's algorithm in Qiskit, problems with growing number of qubits
I am building a n-qubit circuit for Grover's algorithm using the material on Qiskit Github as a guide.
https://github.com/Qiskit/textbook/blob/main/notebooks/ch-algorithms/grover.ipynb
In particular I ...
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Quantum Monte Carlo and Quadratic Speedup
In classical Monte Carlo, when we want to predict a value for something which has inherent uncertainty, such as predicting a stock value, we use a mathematical model like Geometric Brownian Motion and ...
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Amplitude Amplification without access to the Algorithm A: $\mathcal{A}|0\rangle=|\psi\rangle$
I am working on my thesis and I am in a situation where I want to, ideally, use amplitude amplification (as described by Brassard et al. 2000 / arXiv). This is a generalisation of Grover's Search. It ...
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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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Dot product estimation using Amplitude Estimation
To my understanding—from this paper for example (arXiv)—given a state $\frac{1}{\| w\| } \sum_x w(x) |x\rangle$ and given an algorithm that produces $k$ copies of the state $|u\rangle$, we can ...
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How to solve "Maximum allowed dimension exceeded" while trying to run Grover's algorithm in IBM backend?
I am trying to run Grover's algorithm on IBM backend. The previous code was running fine but due to some recent changes in qiskit, I had to modify it. But I can't seem to fix this "Maximum ...
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How to add the basis state $\vert 0 \rangle$ to an arbitrary uniform superposition state?
There is an unknown uniform superposition state $$\vert \psi \rangle = \frac{1}{\sqrt{N}} (\vert k_1 \rangle + \vert k_2 \rangle + \cdots + \vert k_N \rangle),$$ where $$k_1 \neq k_2 \neq \cdots k_p \...
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Step by step explanation of Grover diffusion operator quantum circuit for 2 qubits
I am a newbie to quantum computing and recently came across Grover's algorithm. I'm now trying to understand its quantum circuit for 2 qubits.
I have understood the oracle which marks the correct ...
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How to solve circuit error in qiskit
I am trying to run the grover's algorithm in qiskit using Google collab.
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Constructing Conditional Phase Shift in Grover's Algorithm and Optimality of Grover's Algorithm for Multiple Solutions
I’m currently working through some questions related to Grover's algorithm and need help with the following:
Conditional Phase Shift Construction using single qubits and two-qubits gate? Also, how ...
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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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