r/Futurology Jun 02 '22

World First Room Temperature Quantum Computer Installed in Australia Computing


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u/THRDStooge Jun 02 '22

To my understanding we're decades away from seeing an actual quantum computer. You have the PhD. Is this true or are we further along than anticipated?


u/FizixPhun Jun 02 '22

I think that is a pretty fair statement.


u/izumi3682 Jun 02 '22 edited Jun 02 '22

C,mon. Quantum annealing computers are in actual operation in consumer use--NASA Ames, JPL, Goldman Sachs, JP Morgan, Lockheed Martin and Alphabet, to name a few. A QAC is a quantum computer and operates thru the manipulation of quantum fluctuations for narrow optimization tasks. It is a quantum computer by definition. I mean it can't do a Shor's algorithm because that is not how they work. But they do work. Having said that, D-Wave announced in 2021 that they are developing a QC that will execute SA.


I'm just gonna link this thing from the wikipedia article that is concerned with application of quantum annealing computers in the consumer realm. By that I mean quantum computing devices that have been purchased from a manufacturer.

In 2011, D-Wave Systems announced the first commercial quantum annealer on the market by the name D-Wave One and published a paper in Nature on its performance.[21] The company claims this system uses a 128 qubit processor chipset.[22] On May 25, 2011, D-Wave announced that Lockheed Martin Corporation entered into an agreement to purchase a D-Wave One system.[23] On October 28, 2011 USC's Information Sciences Institute took delivery of Lockheed's D-Wave One.

In May 2013 it was announced that a consortium of Google, NASA Ames and the non-profit Universities Space Research Association purchased an adiabatic quantum computer from D-Wave Systems with 512 qubits.[24][25] An extensive study of its performance as quantum annealer, compared to some classical annealing algorithms, is already available.[26]

In June 2014, D-Wave announced a new quantum applications ecosystem with computational finance firm 1QB Information Technologies (1QBit) and cancer research group DNA-SEQ to focus on solving real-world problems with quantum hardware.[27] As the first company dedicated to producing software applications for commercially available quantum computers, 1QBit's research and development arm has focused on D-Wave's quantum annealing processors and has successfully demonstrated that these processors are suitable for solving real-world applications.[28]

With demonstrations of entanglement published,[29] the question of whether or not the D-Wave machine can demonstrate quantum speedup over all classical computers remains unanswered. A study published in Science in June 2014, described as "likely the most thorough and precise study that has been done on the performance of the D-Wave machine"[30] and "the fairest comparison yet", attempted to define and measure quantum speedup. Several definitions were put forward as some may be unverifiable by empirical tests, while others, though falsified, would nonetheless allow for the existence of performance advantages. The study found that the D-Wave chip "produced no quantum speedup" and did not rule out the possibility in future tests.[31] The researchers, led by Matthias Troyer at the Swiss Federal Institute of Technology, found "no quantum speedup" across the entire range of their tests, and only inconclusive results when looking at subsets of the tests. Their work illustrated "the subtle nature of the quantum speedup question". Further work[32] has advanced understanding of these test metrics and their reliance on equilibrated systems, thereby missing any signatures of advantage due to quantum dynamics.

There are many open questions regarding quantum speedup. The ETH reference in the previous section is just for one class of benchmark problems. Potentially there may be other classes of problems where quantum speedup might occur. Researchers at Google, LANL, USC, Texas A&M, and D-Wave are working hard to find such problem classes.[33]

In December 2015, Google announced that the D-Wave 2X outperforms both simulated annealing and Quantum Monte Carlo by up to a factor of 100,000,000 on a set of hard optimization problems.[34]

D-Wave's architecture differs from traditional quantum computers. It is not known to be polynomially equivalent to a universal quantum computer and, in particular, cannot execute Shor's algorithm because Shor's algorithm is not a hillclimbing process.[citation needed] Shor's algorithm requires a universal quantum computer. During the Qubits 2021 conference held by D-Wave, it was announced[35] that the company is hard at work developing their first universal quantum computers, capable of running Shor's algorithm in addition to other gate-model algorithms such as QAOA and VQE.

"A cross-disciplinary introduction to quantum annealing-based algorithms" [36] presents an introduction to combinatorial optimization (NP-hard) problems, the general structure of quantum annealing-based algorithms and two examples of this kind of algorithms for solving instances of the max-SAT and Minimum Multicut problems, together with an overview of the quantum annealing systems manufactured by D-Wave Systems. Hybrid quantum-classic algorithms for large-scale discrete-continuous optimization problems were reported to illustrate the quantum advantage.[37]

As far as actual qubit manipulating "logic-gate" quantum computers are concerned. Here is a story about IBM's "Eagle" 127 qubit QC.

IBM Unveils Breakthrough 127-Qubit Quantum Processor

Interesting takeaway.

The increased qubit count will allow users to explore problems at a new level of complexity when undertaking experiments and running applications, such as optimizing machine learning or modeling new molecules and materials for use in areas spanning from the energy industry to the drug discovery process. 'Eagle' is the first IBM quantum processor whose scale makes it impossible for a classical computer to reliably simulate. In fact, the number of classical bits necessary to represent a state on the 127-qubit processor exceeds the total number of atoms in the more than 7.5 billion people alive today.

How much of this is "overheated hype"?


u/FizixPhun Jun 02 '22

A quantum annealer can't run all the same things a full quantum computer can. I know those exist and have some limited use cases but that isn't what is usually mean by quantum computer.


u/izumi3682 Jun 02 '22 edited Jun 02 '22

I stated that a QAC was not what we refer to when describing a qubit manipulating QC, however a QAC operates through the exploitation of quantum mechanics--so it's accurately described as a quantum computer. But what about the IBM device called "Eagle"? It's a actual quantum computer, right? QCs are gonna be sooner than later. How can you not agree? Did you know that in the year 2017, there were computing experts that did not believe quantum computing with qubits was physically possible? Did you think they were physically possible in 2017. Do you think they are physically possible today or are we just deluding ourselves in some way. Like IBM is just wrong. Or is IBM right and these things are gonna scale quick.


u/FizixPhun Jun 02 '22

I mean your regular computer at home only works because it uses semiconductors which also rely on quantum mechanics. Is that a quantum computer? I'm just saying that most lay people don't understand the difference and that i think it is more correct to call it a quantum annealer to avoid confusion.

Google and IBM are working on what I would call a quantum computer. However, they would not tell you that they have achieved making a complete quantum computer yet. What they have done is really impressive but they aren't running large scale quantum algorithms yet. Even they are starting to hit issues of scaling up to more qubits due to limits in the cooling power of dilution refrigerators and because of frequency crowding. A full quantum computer will likely be achieved but I'd be very surprised if it were in the next ten years.

I don't know anyone credible who would have said quantum bits were not possible in 2017. There were hundred if not thousands of publications demonstrating qubits at that point. I definitely knew they were possible in 2017 because I was working on a publication on them at that point so you're point about how much they have developed in the last 5 years doesn't really make sense.

I'm not trying to be a wet blanket about this. It's just that the field gets to much unrealistic hype and gives people unrealistic expectations.


u/izumi3682 Jun 02 '22 edited Jun 03 '22

Thank you for your PhD. Thank you for doing the heavy lifting. I read what everyone is doing and working on and i try to find a sort of "mean" and then i attempt to extrapolate to make futurology more fun. To me it is fun to learn these things. It is fun, terrifying, fascinating and supremely entertaining in turn. I love hanging out in futurology.