# quantum computer

HHL algorithm I am going to study quantum algorithms in my own way using qiskit. Since this is a record of my personal study, I may have left out a lot of explanations. I am following the qiskit website. https://qiskit.org/textbook/ja/ch-applications/hhl_tutorial.html The reason why qiskit was categorized as a Rec (recommendation system) in my blog was all to understand HHL. Currently, I am interested in recommender systems and am developing them. Linear equations are used with high probability when solving mathematical models using computers, and it is important for recommendation systems to extract features with high user engagement from the User-Item matrix.
Grover’s algorithm I will be using qiskit to study quantum algorithms in my own way. Since this is a record of my personal study, I may have left out a lot of explanations. I am following the qiskit website. https://qiskit.org/textbook/ja/ch-algorithms/quantum-phase-estimation.html Grover’s algorithm is famous for its ability to perform search problems very fast. For the search problem of an array with a normal list structure, performing a sequential search requires a computation time of $O(1)$ in the best case and $O(N)$ in the worst case.
Shore’s algorithm I will be using qiskit to study quantum algorithms in my own way. Since this is a record of my personal study, I may have left out a lot of explanations. I am following the qiskit website. https://qiskit.org/textbook/ja/ch-algorithms/quantum-phase-estimation.html I would like to proceed to the Shore algorithm, which has the potential to break the RSA cipher, where quantum computers are expected to have the biggest impact. The RSA currently used in web systems is easy to calculate the product of two primes, but the inverse factorization takes $O(N)$ of computation, and nowadays, at 1000 bits (about 300 digits), it takes as much time as the history of the universe, even with a supercomputer, making it practically impossible This means that it is practically impossible.
Quantum phase estimation I am going to use qiskit to study quantum algorithms in my own way. This is a record of my personal study, so I may have left out a lot of explanations. I am following the qiskit website. https://qiskit.org/textbook/ja/ch-algorithms/quantum-phase-estimation.html Let’s study quantum phase estimation, which is the most important quantum algorithm. It is used in a variety of algorithms and understanding it is essential. It is a combination of phase kickback and quantum Fourier inversion, and estimates the eigenvalues of an eigenvector for a unitary operator (its phase).
Quantum Fourier transform I’m going to study quantum algorithms in my own way using qiskit. This is a record of my personal study, so I may have left out a lot of explanations. I am following the qiskit website. https://qiskit.org/textbook/ja/ch-algorithms/quantum-fourier-transform.html Next, let’s review the quantum Fourier transform. I thought I understood it when I was in school, but I’ve completely forgotten it, so I’m going to have to relearn it from scratch.
Simon’s algorithm I’m going to use qiskit to study quantum algorithms in my own way. Since this is a record of my personal study, I may have left out a lot of explanations. I am following the qiskit website. https://qiskit.org/textbook/ja/ch-algorithms/simon.html In this article, I will try to understand Simon’s algorithm by following the formula. The difference is that Simon’s algorithm determines whether the function $f(x)$ is a 1:1 function or a 2:1 function.
Dioichi-Josa’s algorithm I will be using qiskit to study quantum algorithms in my own way. Since this is a record of my personal study, I may have left out a lot of explanations. I am following the qiskit website. https://qiskit.org/textbook/ja/ch-algorithms/deutsch-jozsa.html In this article, I will try to deepen my understanding of the Doichi-Josa algorithm by following the formulas. It is my lack of study, but when I studied quantum information as a student, I did not know about the Doychi-Josa algorithm.
2 quantum bits I will be using qiskit to study quantum algorithms in my own way. Since this is a record of my personal study, I may have left out a lot of explanations. I am following the qiskit website. https://qiskit.org/textbook/ja/preface.html Last time we focused on the basic usage and gating operations for one qubit, this time we will understand operations for two qubits. github The file in jupyter notebook format is here google colaboratory If you want to run it on google colaboratory here Author’s environment !
How to use qiskit and a single qubit I am going to use qiskit to study quantum algorithms in my own way. Since this is a record of my personal study, I may have left out a lot of explanations. I am following the qiskit website. https://qiskit.org/textbook/ja/preface.html github The file in jupyter notebook format is here google colaboratory To run it in google colaboratory here Author’s environment !sw_vers ProductName: Mac OS X ProductVersion: 10.