Questions tagged [d-wave]
A quantum computing company, based in Burnaby, British Columbia, Canada, mostly known for their quantum annealing computers. An early rendition of these, D-Wave One, was the first commercially available quantum computer. (Wikipedia)
96
questions
2
votes
1
answer
57
views
Complexity of minor embedding [closed]
I am looking for a proof why the minor embedding problem (or minor graph search or minor testing) belongs to NP-complete problems.
I would like to find a paper or in general an explanation that shows ...
1
vote
0
answers
59
views
Performance of quantum annealing systems vs gate based ones
Quantum annealers like D-Wave can be used to solve Quadratic Unconstrained Binary Optimization (QUBO) which is a NP Hard problem (see here) while gate based quantum computers, like the ones created by ...
- 11
2
votes
0
answers
22
views
Solving KnapSack problem on D Wave hybrid CQM
I am solving 01 KnapSack problem for 500k items with the help of hybrid CQM solver of D Wave. And for comparison I solved same problem with CPLEX. Solution quality of CPLEX solver is better than D-...
- 63
3
votes
1
answer
69
views
Multiplying two real variables in D Wave
I have two real variables from dimod:
from dimod import Real
A = Real("A")
B = Real("B")
However, when I try to multiply them ...
2
votes
1
answer
107
views
D-Wave hybrid solver
I am interested in using the D-Wave CQM hybrid solver for solving the job shop problem.
I would like to get more information about the internal working of this solver but I have been
unable to find ...
- 21
0
votes
0
answers
25
views
How to add expressions to a Binary Quadratic Model, similar to CQM?
In a constrained quadratic model, we are able to create expressions like this:
...
- 121
1
vote
0
answers
31
views
Who is currently working on coherent Ising machines (classical analog devices)?
Can you share some papers on that subject? Review papers would be highly appreciated. What are limitations in terms of connectivity between different spins?
- 331
1
vote
0
answers
42
views
Comparing BQM and CQM solving for a tree-path problem
I'm currently working on a project for my thesis regarding BQM and CQM optimisation for a path problem.
Without going too much on the details, here's some info:
the structure is a tree, where all the ...
2
votes
0
answers
124
views
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?,...
- 85
4
votes
1
answer
80
views
QPU vs. Solvers
I am trying to understand the roles of the QPU and the solvers in a quantum device, specifically I am reading for this purpose the documentation of D-Wave.
While it is clear to me that the QPU of a ...
- 59
4
votes
1
answer
856
views
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 ...
- 1,886
20
votes
2
answers
3k
views
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 ...
- 1,886
3
votes
1
answer
84
views
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 ...
- 241
0
votes
1
answer
41
views
Is there any another method for adjusting transverse field? (D'wave)
By using QUBO formula, I can't take in Transverse field equation
I was tried using of annealing schedule but it was failed .
Is there any another method for adjusting transverse field?
(I want to get ...
- 1
1
vote
1
answer
135
views
How to use D-Wave decomposers?
I'm currently trying to work on a minimization problem using D-Wave hybrid and quantum machines.
The problem is, shortly, an energy optimization for a network of switches and servers, linked as a ...
0
votes
1
answer
72
views
How to keep the initial Hamiltonian in D Wave
So the D wave machine claims to start in an eigenstate of the Pauli X term in the transverse Ising model Hamiltonian,
$$
-\frac{A(s)}{2}\sum_{i} \sigma^{x}_{i}
$$
and then $A(s)$ is turned off slowly ...
- 159
4
votes
2
answers
790
views
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 ...
- 41
1
vote
2
answers
707
views
D-Wave Cloud Service - Pricing for Academic Research Project
In D-wave's web portal, I found 3 different ways that one can gain access to more QPU/Hybrid Solver time. One of them is the academic research project. Does anyone here have experience of carrying out ...
- 11
5
votes
0
answers
42
views
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 ...
- 474
2
votes
0
answers
64
views
Absolute value of a BQM: how to substitute it with constraint?
I need to build an expression for the objective to be minimized which is based on the L1-norm. For doing this, I need to take the absolute value of a BQM, which is not possible, at least at the moment ...
- 151
1
vote
0
answers
143
views
How to add constraints to a BQM?
BQM is unconstrained by definition.
I need to submit a knapsack problem with two constraints (equality constraints + inequality constraints) to a quantum annealer (DWaveSampler).
How would you set the ...
- 151
2
votes
0
answers
31
views
Why does method to_bqm not maintain variables order?
When converting to bqm with .compile().to_bqm(), the original order of the variables is not maintained.
To reproduce:
...
- 151
7
votes
1
answer
329
views
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♦
- 26.3k
1
vote
1
answer
175
views
How to declare non-binary decision variables in an optimization problem?
I am working on a logistics problem which require me to find the optimum quantity of product to be manufactured and also to be shipped to satisfy the customer demand. I have made a decision variable $...
user21029
1
vote
0
answers
74
views
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 ...
- 11
3
votes
2
answers
145
views
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 ...
- 2,081
3
votes
1
answer
437
views
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 ...
- 471
3
votes
1
answer
212
views
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 ...
- 495
7
votes
3
answers
3k
views
How are IBM's 127 qubits more potent than the 5760 qubits D-Wave - Advantage_system6.1?
Hi I'm a newbie in quantum computing recently I had a look at the AWS braket and I've seen they had a machine called D-Wave - Advantage_system6.1 that has 5760 qubits but when I googled the highest ...
- 193
1
vote
1
answer
360
views
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 & ...
- 17
4
votes
0
answers
85
views
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 ...
- 151
3
votes
1
answer
413
views
Penalty formulation regarding inequalitties
During the formulation of a QUBO matrix I have a question regarding penalty formulation.
Once I'm done with QUBO formulation such as $x_{i}Ax_{j}$ where A is the QUBO matrix, $x_{i}$ and $x_{j}$ are ...
- 255
7
votes
0
answers
129
views
Qubit fidelity of DWAVE device
Since DWAVE quantum device is constructed using superconducting flux qubits, each qubit cannot be produced identically so that the fidelity of the qubit must be different. DWAVE only provides the ...
- 1,393
3
votes
1
answer
111
views
Is D-Wave advantage a noisier hardware compared to the older D-Wave 2000?
Is D-Wave Advantage noisier hardware compared to the older D-Wave 2000? There is any measure of the noise within the vendor's whitepapers, the quantum annealer analogue of e.g. decoherence time, ...
- 795
6
votes
1
answer
263
views
Can D-Wave machines solve QUBO problems more efficiently than gate model devices?
I'm new to quantum annealing and D-Wave computer. I saw that it has about 5000 qubits which can solve a QUBO problem with 5000 variables.
From my understanding, if we use a gate model device, say, an ...
- 1,393
2
votes
1
answer
223
views
How do we calculate the offset in a QUBO formulation?
I am aware that for a quadratic optimization problem, we are required to minimize $y$ where $y = x^t Q x$ where $x$ is a column vector of binary variables and $Q$ is a QUBO matrix. I have the ...
- 179
1
vote
0
answers
220
views
What is the role of Josephson junctions and biases in the D-Wave qubit structure?
On the D-Wave 2000Q there are up to 2048 qubits and 5600 coupler. A commonly used picture of one of such qubits is attached below.
Each qubit is realized by a loop of niobium controlled by Josephson ...
- 11
1
vote
0
answers
72
views
What should be the lowest energy of this graph isomorphism QUBO?
I am trying to study QUBO formulations of the graph isomorphism problem. I tried implementing the QUBO matrices given by the algorithms described in here. For the two input graphs therein, I am ...
- 179
2
votes
0
answers
108
views
Sampling from a given Boltzmann distribution using D-Wave systems
For a project I'm working on, I want to use D-Wave systems to estimate the probabilities of a Boltzmann distribution given a QUBO (Hamiltonian), this being performed through sampling and the use of ...
2
votes
1
answer
268
views
From general Hamiltonian to Ising Hamiltonian
I would like to convert my qubit hamiltonian fom the HeH+ system that I have obtained using Qiskit to an Ising or QUBO model. I have seen multiples examples from QUBO to Qubit Hamiltonian but on the ...
- 155
2
votes
1
answer
276
views
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 ...
- 391
1
vote
2
answers
192
views
The Adiabatic Theorem - How to derive Schrödinger equation in the "s" variable
I'm studying Adiabatic Quantum computing from the book
"Adiabatic Quantum Computation and Quantum Annealing: Theory and Practice" by Catherine C. McGeoch at D-Wave.
The section THE ...
- 143
2
votes
0
answers
85
views
Output of D-Wave LeapHybrid solver takes long to evaluate
we made the strange observation that the evaluation of the output in form of the dimod.SampleSet takes a long time to evaluate especially in comparison to the actual sampling step. Here is a minimal ...
- 21
4
votes
0
answers
83
views
How to improve embedding process in D-Wave?
I am quite new to the quantum computing field.
Currently, I am trying to solve a combinatorial optimization problem on a D-Wave system, which I successfully translated into QUBO form. I also managed ...
1
vote
1
answer
62
views
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 ...
- 153
4
votes
0
answers
57
views
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, ...
- 93
3
votes
1
answer
123
views
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
...
- 153
4
votes
2
answers
240
views
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 ...
2
votes
1
answer
566
views
From Qiskit QuadraticProgram to problem model accepted by d'wave ocean
Is there a way to convert QuadraticProgram (qiskit.optimization.problems.QuadraticProgram) to BQM used in D'wave ocean (e.g. <...
10
votes
3
answers
1k
views
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 ...
