Questions tagged [annealing]
It is a metaheuristic for finding the global minimum of a given objective function over a given set of candidate solutions (candidate states), by a process using quantum fluctuations. (Wikipedia)
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I would like to know the textbook/paper on hamiltonian for rf-SQUID
I am a graduate student in the Department of Computer Engineering, and I am currently doing research on superconducting quantum computers. In particular, I am focusing on quantum annealing machines ...
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Can D-Wave presently solve real-world problems that conventional computers cannot solve?
There are number of threads on this site about the ability of QCs solving real-world problems (see for example What are the practical applications of quantum computing in engineering by the year 2030?,...
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Does the D-Wave hardware show any advantage for academic use-cases, for example in condensed matter physics?
The D-Wave team put out a few papers (like this one and this one) in the last few years describing how their methods can find ground states of certain spin-glass Hamiltonians faster than classical ...
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Did D-Wave show quantum advantage in 2023?
I would like to know your thoughts on whether or not D-Wave has shown a a smoking-gun example of quantum advantage this year. I am genuinely not quite sure what to think, but I believe the answer to ...
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Python code for D-Wave Annealer
In the below screenshot, I am aware of resolving the issue by reducing num_reads as the annealing time is exceeding my allowance. Although it works, my question ...
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How to translate a problem for a gate-based quantum computer into an equivalent problem for a quantum annealer?
There is an offhand claim (somewhere) in https://www.youtube.com/watch?v=eFIk7wpU5vA that a quantum annealer is in principle a completely equivalent machine to a gate-based quantum computer, in the ...
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How can I exactly solve a Quadratic Model with integer variables using DWave Ocean classical solvers?
As an example, let's consider the following simple QuadraticModel problem with just 3 INTEGER variables:
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Why is a large quantum annealer likely to leave its ground state?
For problems of significant size in quantum annealing, I have read that even for slow transitions, the annealer is likely to leave its ground state. I have not fully grasped the meaning of why exactly ...
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Extracting a QUBO matrix from pyqubo
I am benchmarking different QUBO solvers for a very simple instance of the knapsack problem.
Some of these solvers require the matrix, Q, and offset, b, from the equation:
$$
\begin{equation}
x^{\...
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Is there any quantum annealer simulator offered by DWave?
I am searching for quantum annealer simulator offered by DWave. I found classical solvers in dimod packages that implement simulated annealing, but I couldn’t find solver that simulates the real ...
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Grover's algorithm to maximize QUBO functions
I'm trying to maximize a QUBO function f(x,y,z) = 3xy + 4xz - 3yz + 11y + z. How can I use Grover's algorithm to do this?
I've been told to encode this cost ...
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What is meant by the "quasi-locality" of the interactions in a quantum annealer?
I am reading a paper on Quantum Annealing [1], and the paper writes the following:
"one of the fundamental challenges in building a fully programmable quantum annealer is the competing ...
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AQC definition modifications costs and pay-offs
I was wondering if one can think of a more general relation between alleviating conditions for the state in which the evolution takes palce in AQC paradigm and constraining the structure of the ...
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How to compare Quantum Annealing and Adiabatic Quantum Computing?
I'm still unsure on the difference between adiabatic quantum computing (AQC) and quantum annealing (QA). Please critique these interpretations:
AQC: Define a Hamiltonian with an easy-to-prepare ...
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Understanding of the transverse-field Ising model
I want to make sure whether I do understand the transverse Ising model correctly or not. The classical Ising model describes the interaction between spins in a grid and the state of spins can be ...
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Using entropy quantum computing for solving optimization problems
I would like to follow up on this question (What is Entropy Quantum Computing?).
Company Quantum Computing Inc. announced that they made their quantum computer aimed at solving binary optimization ...
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What arguments point towards D-Wave devices being potentially useful?
I'm looking for any evidence pointing towards D-Wave's approach to quantum computation being promising to achieve any sort of computational advantage with respect to classical devices.
Note that I'm ...
glS♦
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How does Fujitsu's digital annealer work?
I have read Fujitsu's white paper for a brief introduction to their device:
http://marketing.us.fujitsu.com/rs/407-MTR-501/images/quantum-inspired-computing.pdf
As far as I know, Fujitsu's hardware is ...
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How can a QUBO matrix with many identical, non-zero off-diagonal terms be made sparse?
I am with a QUBO matrix where entire off-diagonal sections are with the same value, which is the same between sections. Consider the following example (much smaller than those I am actually working ...
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Can D-Wave machines be applied to simulate Hamiltonians arising in quantum physics?
AFAIK D-Wave primarily advertises their machines as tools for solving problems with classical input, i.e. when the Hamiltonian to be minimized is a function of $Z$s.
Can one use their machines in ...
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Why is quantum annealing often associated with the Ising model?
Quantum annealing is often associated with Ising Model, in the sense that the problem Hamiltonian needs to be in the form of an Ising Hamiltonian.
Is this because the physical description of the ...
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Is there any rigorous proof that Quantum Annealing provides a quantum advantage?
Is there any rigorous proof that Quantum Annealing (QA) is of any benefit (e.g. in terms of time to optimal solution, convergence rate, etc.) for a specific problem? Or any empirical evidence for the ...
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Is digital quantum computing more powerful than the analog one?
What I get so far:
Analog quantum computing:
The Hamiltonian is implemented on the QC, solution is found by e.g. quantum annealing. The whole state is changing continuously.
Digital quantum computing:
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Convert Hamiltonian to Ising Formulation or QUBO
I have a tridiagonal Hamiltonian matrix that I need to convert to QUBO or Ising format to use D-Wave's quantum annealing solvers. For a generic tridiagonal:
\begin{pmatrix}
a_1 & b_1 \\
c_1 & ...
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Why do Quantum Annealer have (currently) a higher scaling potential?
One may categorize quantum computers in two classes: Quantum Annealer and (universal) Gate Quantum Computers. There may be also other categories. IBM announced 127 Qubits for their next Gate Quantum ...
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Quantum Annealing vs Quantum Monte Carlo: can QMC do all that QA can?
I'm working on an essay about quantum technology, and the connection between the annealing algorithm and quantum computing hardware is an important transition in the text. I'd like to know if there is ...
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Is the Quantum Annealing model universal?
I understand that the D-Wave Quantum Annealer they have today is not a universal quantum computer.
Is the reason that it's not universal because of the lack of error correction and lack of all-to-all ...
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Mathematical definition of QUBO problem
The quantum annealing approach is using the equivalence between QUBO matrix and Ising Hamiltonian to solve the problem. Therefore, it is necessary to transform a NP-hard problem into a QUBO matrix. ...
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Can any binary problem be solved by a QUBO?
As far as I know, if a computing problem can be solved by the quantum annealing approach, it also means the solution space should be binary, e.g., a vector that only contains either 0 and 1. Otherwise,...
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Any simulator packages for quantum annealing/adiabatic quantum computation?
Are there any simulator packages for quantum annealing/adiabatic quantum computation, like Qiskit Aer but for quantum annealing?
There seems to be only classical heuristics in D-Wave Ocean package, ...
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What is the relationship between the mixing operators and initial states found in QAOA and Quantum Annealing?
In many papers, the QAOA is shown to be intimately related to Quantum Annealing/Quantum Adiabatic Algorithm/Adiabatic Quantum Optimization.
The mixing operator in the QAOA is described by Hadfield as ...
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Understand final Hamiltonian in Quantum Annealing
Currently, I’m studying quantum annealing in which the system evolves according to the Hamiltonian:
$$
H(t) = H_F + \Gamma(t) H_D,\tag{1}
$$
where $H_F$ is a final (classical) Hamiltonian, $H_D$ is a ...
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Example of lower bound on spectral gap for adiabatic quantum computing
is there a list of reference for which the authors prove a lower bound of the spectral gap for an adiabatic quantum algorithm? I.e. I am searching for examples where the authors solve a problem with ...
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How is eigendecomposition of a Hamiltonian equivalent to finding the minimum of an energy function?
This question is in regards to Dwave's quantum computer which is tailored to solve QUBO problems using quantum annealing.
QM tells us that the ground state of a quantum system is given by the ...
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Question about the counter diabatic(CD) term in Digitized Adiabatic Quantum Computing
Recently I have read two articles about the Digitized Adiabatic Quantum Computing(DAQC), and tried to factorize $35=5\times7$ and $2479=67\times37$.
But some problems came when trying to solve the ...
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What type of tasks it is possible to solve on a quantum simulator?
In this article, the author claimed that researches from Harvard and MIT created 256 qubits quantum simulator. However, we are not talking about piece of software on a classical computer but actual ...
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Quantum annealing - studies showing empirical evidence for better performance in comparison with classical computers
Currently, it is not known wheter quantum anneling or algorithms like VQE and QAOA for general purpose quantum computers bring about any increase in computational power. However, there are some ...
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What do the numbers in the Ising sampleset mean?
I am trying to create a portfolio optimization with the DWave Quantum Computer. I wrote some code trying to somehow reconstruct the following Ising model paper:
Ai ...
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What is the state-of-the-art annealing device for solving Ising problems?
I understand that in addition to D-Wave's quantum annealer, there have been other unconventional (although non-quantum) Ising solvers like the one from Toshiba, Fujitsu, the Coherent Ising machine, ...
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Is Quantum Annealing threatened by the Quantum Gates approach?
Since Quantum Annealing is extremely powerful for optimization it is limited in scope.
However, when a universal Quantum Computer based on gates arrives, it will have a wider scope including ...
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How to decide bias in Hamiltonian Ising model?
I am trying to code finance portfolio optimisation problem into a quantum annealer, using the Hamiltonian Ising model. I am using the dwave module
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Relationship of Adiabatic Quantum Computing speedup to Quantum Random Walk hit time
Considering the following two phenomena:
Adiabatic quantum computing in general exhibits a quadratic speedup over classical simulated annealing, though for some Hamiltonians it may be faster (while ...
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Why is it so important to have uniform chain lengths in a minor embedding?
Very brief background
In quantum annealing, the discrete optimization problem we wish to solve (such as finding the minimum of $b_1b_2 - 3b_1 + 5b_3b_4$ for binary variables $b_i$) may have a ...
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Are spin-glass problems NP (-complete)?
It is well known that finding ground states for spin-glass systems (Ising, XY...) is NP-hard (at least as hard as the hardest NP-problems) so that they can be efficiently used to solve other NP ...
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Adiabatic Quantum Computer e intermediate Hamiltonian evolves the state within the manifold
The Adiabatic Quantum Computer is implemented by slowly increasing the parameter s from 0 to 1 in the intermediate Hamiltonian $[\hat{H}(s) = \hat{H}_{input} + (1-s)\hat{H}_{init} + s\hat{H}_{circuit}]...
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In quantum adiabatic simulation, is the $s$ in $(1-\frac{s}{T})H_{in}+\frac{s}{T} H_{cl}$ related to the $t$ in $e^{-iHt}$?
I just want to do a whole adiabatic calculation on quantum circuit.
To prepare two Hamiltonian of $H_{initial}$ and $H_{classical}$ and solve $H_{classical}$ using adiabatic calc like quantum ...
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What is the computational complexity of quantum annealing?
Quantum annealing can be thought of as a black box solver that can find approximate solutions to hard optimization problems. For example, D-Wave quantum annealers can approximately solve quadratic ...
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D-WAVE QUBO Matrix Form
I am trying to write down this problem (friend/enemy graph) in a polynomial matrix form in order to understand quantum annealing better, but it seems like the problem should actually be split into ...
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Can QAOA be considered as simulation of a quantum annealer on a gate-based quantum computer?
Quantum annealers are single purpose machines allowing to solve quadratic unconstrained binary optimization (QUBO) problems. QUBO problems have following objective function:
$$
F=-\sum_{i<j}J_{ij}...
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Is either the adiabatic or the diabatic version of quantum annealing known to be theoretically more powerful than the other?
Quantum annealing can be considered either in the perfectly adiabatic "slow" limit (in which case it's usually referred as "adiabatic quantum computing" (AQC) instead of "...
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