MSFT demonstrates formerly elusive physics needed to build scalable qubits

https://news.microsoft.com/innovation-stories/azure-quantum-majorana-topological-qubit/

by rahulravu96 • 4 years ago

75 14 4 years ago

news.microsoft.com

itcrowd• 4 years ago

Simultaneously, prof. Kouwenhoven of Delft's Microsoft lab has resigned / left Microsoft (source only in Dutch). He was leading the Dutch effort into Majora particles and his lab was involved in a scandal involving data manipulation, tunnel vision and wishful thinking that led to the now-false claim of the first Majoranas being observed.

https://www.volkskrant.nl/wetenschap/leo-kouwenhoven-nederla...

wrycoder2• 4 years ago

I think that referring to the incident as a "scandal involving data manipulation" is unfair. An independent review stated the following:

On the same day as the retraction, an independent report written by four physicists that was commissioned by TU Delft concluded there were no instances of data fabrication. “There was some degree of data selection in what was published,” says Patrick Lee from Massachusetts Institute of Technology, who was one of the authors of the report. “I don’t think this was done with malice. I think they were caught up at the excitement of the moment.” Lee notes that “some mistakes” were made by the team such as a calibration error, which they discovered after the publication of the paper. “They were aware of it and they came out with it without holding back anything,” says Lee. Indeed, Lee adds that he does not think that Microsoft is in trouble given its links to TU Delft. “It is a setback, but it should not derail the whole enterprise,” adds Lee.

https://physicsworld.com/a/retraction-of-nature-paper-puts-m... (March 2021)

klyrs• 4 years ago

"Some degree of data selection" is a helluva spin on chopping out a large, central portion of the data in the region of interest.

itchyjunk• 4 years ago

I felt like my understanding about what has happened didn't change before and after this article. I admit I skimmed through it and I didn't follow all the links but what I got out of this is that we were excited about this for a long time and wasn't sure if it was possible but now knows its possible. Something about topological qbits (which I don't think the article cares to directly define and yes i am to blame for not following the links). I just think a shorter article that gave a few definition and compared and contrasted the pros and cons would have helped me more as a layman. But maybe this is aimed at potential customers who get more out of the article than I do.

thesz• 4 years ago

Here's explanation: https://en.wikipedia.org/wiki/Topological_quantum_computer#E...

It looks like "topological qubits" that are used in MSFT breakthrough is a sort of "surface-spread" qubits, because they are two dimensional structures. They are then "braided" instead of "entangled" to specify a problem to solve.

What is interesting here is that error correction for temperature fluctuations amounts to give these braids wider separation (in actual space). Which, on one hand, looks like simplification of the solution, but, on the other hand, still requires more space just like additional qubits in regular quantum computer.

wrycoder2• 4 years ago

Yes, that was a whole pile of marketing-engineering fluff that never made an attempt to explain what they had accomplished. The links in the article don't help either. They did hit climate change, though.

They stated that the qubits they are working with are topological defects similar to knots. OK, but defects in the topology of what? Spacetime? The Maxwell potential? Hilbert phase space?

How many topological qubits are needed to produce a logical qubit?

Then they mentioned nanowires connecting the topological qubits. Are those just tiny wires, or is there a quantum phenomenon associated with them? How is the readout done? I assume it's destructive?

As an aside, with all the subtle research being done on qubits and entanglement, I would have expected some clarity in the fundamental interpretation of QM by now (Copenhagen, Manyworlds, Bohmian), but I haven't heard of anything new for awhile.

sp332• 4 years ago

This article from Ars Technica describes the topology and the quantum effect they're going for. https://arstechnica.com/science/2022/03/microsoft-announces-...

whoomp123422• 4 years ago

cue: article to tell me how qubits represent both 0 and 1 and not tell me anything else about how quantum computing works

gaze• 4 years ago

Topological quantum computers don’t really represent 0 and 1 even like a standard gate based quantum computer or classical computer does. You have a collection of anyons that you move around each other in a way that encodes the computation (see: T-junction). Then you test to see which anyons, when combined, will go away/annihilate. This encodes the result.

whoomp123422• 4 years ago

this response has more information about QC than I have passively read in 5 years.

whaaswijk2• 4 years ago

Are there any experts that can ELI5 this “breakthrough” for us? How much closer does this bring us to a useful number of logical qubits?

vba616• 4 years ago

Not me. But when I read this:

"Figuring out how to feed the world or cure it of climate change will require discoveries or optimization of molecules that simply can’t be done by today’s classical computers, and that’s where the quantum machine kicks in"

I was like "hopefully it will lead to better bullshit meters because mine just exploded"

whaaswijk2• 4 years ago

:-D

benryon• 4 years ago

Original HN post https://news.ycombinator.com/item?id=30671894

MSFT demonstrates formerly elusive physics needed to build scalable qubits

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