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henrylegg.bsky.social
Henry Legg
@henrylegg.bsky.social
540 followers 120 following 150 posts
Lecturer (~asst prof) investigating quantum physics @univofstandrews. My opinions belong to 28 highly trained monkeys and are not those of my employer. Webpage: https://legg.wp.st-andrews.ac.uk/
legg.wp.st-andrews.ac.uk
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · Feb 28
I had made Microsoft Quantum aware of issues before publication of this latest Nature paper (which uses it tune up their devices).

Since they seem to not care, I have make these issues public.

In short: The topological gap protocol and all claims based on it are flawed.

arxiv.org/abs/2502.19560
Comment on "InAs-Al hybrid devices passing the topological gap protocol", Microsoft Quantum, Phys. Rev. B 107, 245423 (2023)
The topological gap protocol (TGP) is presented as "a series of stringent experimental tests" for the presence of topological superconductivity and associated Majorana bound states. Here, we show that...
arxiv.org
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 1d
There are some differences between UK and international BBC.

Still there on their science page, now with a seemingly AI generated picture: www.bbc.co.uk/news/science...
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 1d
NO BBC! Don't summon them, don't do it!
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 1d
The correct decision from the Nobel committee. If they had even muttered the words "quantum computing" the number of start-up founders posting about their quantum crypto coin NFTs would break LinkedIn.
dangaristo.bsky.social
Dan Garisto @dangaristo.bsky.social · 1d
Interesting bit of sociology: They are really studiously avoiding any mention of quantum computing. First and only mention came in the last few words of the presentation by Johansson.
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Reposted by Henry Legg
dulwichquantum.bsky.social
Dulwich Quantum Computing @dulwichquantum.bsky.social · 2d
Our Nobel Prize predictions for the next week. #Nobel2025
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 3d
Justin Timberlake and Tiger Woods bought St Andrews’ only cinema and turned it in to a heartless golf simulator bar.

Glad to see the locals pushing back against this type of tourist trap.

We have some amazing local run pubs in St Andrews!

My favourite comment: “How do I book a cancellation?”
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 4d
It has come to the authors' attention that the unit of 'hour' was not defined in the original manuscript. Within the context of our experiment, 'hour' was used to denote 30 days. The authors confirm that all results within the manuscript are valid and entirely consistent with this definition.
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 4d
Sergey your joke doesn’t work: If they were travelling close to the speed of light then they would have had even less than 22 hours to make the decision (as appears here on Earth).

Please issue an immediate retraction of the joke.
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 7d
Bit grim seeing the FT treat HSBC’s quantum computing theatre as actual news. Why worry about fake news when the establishment press has already been lobotomised by corporate press releases?

I wish HSBC (my mortgage provider) were as flexible with my interest rate as they are with reality…
financialtimes.com
Financial Times @financialtimes.com · 13d
HSBC claims quantum trading breakthrough on.ft.com/4mDbeYG
HSBC claims quantum trading breakthrough
Europe’s largest lender tested a tool developed by IBM on bond market data
on.ft.com
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Reposted by Henry Legg
dulwichquantum.bsky.social
Dulwich Quantum Computing @dulwichquantum.bsky.social · 8d
Meme about noise from quantum industry vs me.
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Reposted by Henry Legg
bullshitquantum.bsky.social
Quantum Bullshit Detector @bullshitquantum.bsky.social · 12d
Bullshit

www.hsbc.com/news-and-vie...
HSBC demonstrates world’s first-known quantum-enabled algorithmic trading with IBM | HSBC News
HSBC announces the world’s first-known empirical evidence of the potential value of quantum computers for solving real-world problems in algorithmic bond trading.
www.hsbc.com
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 13d
Quantum hype meets financial trading 🤢

Also: "The authors declare that they have no known competing financial interests or personal relationships"

How can being employed by HSBC not be a competing interest?

www.hsbc.com/news-and-vie...
HSBC demonstrates world’s first-known quantum-enabled algorithmic trading with IBM | HSBC News
HSBC announces the world’s first-known empirical evidence of the potential value of quantum computers for solving real-world problems in algorithmic bond trading.
www.hsbc.com
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 13d
The promise of spin qubits has always been their potential to leverage existing semiconductor fabrication techniques. As such this is really a very exciting publication… even if you can’t always trust everything published in Nature.

www.nature.com/articles/s41...
Industry-compatible silicon spin-qubit unit cells exceeding 99% fidelity - Nature
Two-qubit operations exceeding 99% fidelity have been demonstrated by silicon devices made with standard semiconductor tooling in a 300-mm foundry environment.
www.nature.com
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 16d
Essentially this is all because in the UK the tuition fee is the main funding for teaching and has been essentially frozen since 2010. It would be unpopular to freeze university funding from the central government, but freezing a tuition fee paid by the students is more acceptable to the public.
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 16d
Physics is an expensive degree to teach, but the funding (i.e. the amount from student fees) is essentially subject independent and has risen nowhere near inflation.
(Not a problem in St Andrews, but that's my understanding)

UK employers also often favour *some* degree over a specific degree.
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Reposted by Henry Legg
gppcarleo.bsky.social
Giuseppe Carleo @gppcarleo.bsky.social · 16d
Or you can go here neos-server.org/neos/solvers... and wait about 0.02 seconds for the problem to be solved exactly 😂
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Reposted by Henry Legg
wahlgroup.bsky.social
Wahl group account @wahlgroup.bsky.social · 16d
This is really scary - I always thought physics was safe. It would be huge loss to see physics departments close across the country.
www.theguardian.com/education/20...
Quarter of UK university physics departments at risk of closing, survey finds
Four out of five making staff cuts as physicists say findings are ‘great concern’ for UK’s leadership in important areas
www.theguardian.com
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 18d
Donald’s H1B visa policy is already a HUGE success. Many people are saying it to me this morning – the most important people. They say, "Donald’s done it again, so clever, real clever.” America already has the BEST brains. Like Einstein. He was American you know.

www.theguardian.com/us-news/2025...
Trump signs proclamation imposing annual $100,000 fee on H-1B visas
Move deals potentially major blow to US tech industry, which relies heavily on workers from India and China
www.theguardian.com
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 18d
I can go one better! I present the queen-orama. With a coherence time of 96 years this will truly revolutionise quantum computing.
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 18d
And here's a totally reasonable AI viewpoint on why hydropower generation correlates with the use of the distracted boyfriend meme.

You see, correlation does imply causation! The AI just knows better than us feeble humans ;)
henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 18d
On a side note: Whilst writing my data analysis lecture this week, I discovered that the spurious correlations on tylervigen.com now come with AI explanations!

They're brilliant: Here's the explanation why GMO corn growth in North Dakota correlates with Google Searches about headaches.
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · 18d
The year I arrive @physastrostand.bsky.social rises to #1 in the UK for Physics in the Times & Sunday Times University League table.

(and we all know that correlation *does* imply causation, right?!)

www.thetimes.com/uk-universit...
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · Sep 8
"We must make fire work. Stop asking why wet sticks no good."
- Grug, circa 50,000 BC

“We must make Majorana work. Stop asking why InAs no good.”
- Microsoft, 2025

pubs.aip.org/physicstoday...
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · Aug 23
Just to set the picture: Last time I did “serious” experiments someone knocked on the door of the lab and asked “is there a reason it’s currently raining liquid nitrogen on us downstairs” (in my defence it was not my fault)
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · Aug 23
I feel compelled to repost my experimental colleagues’ job adverts because physics is ultimately an experimental science and trust me you really don’t want me anywhere near your lab…
wahlgroup.bsky.social
Wahl group account @wahlgroup.bsky.social · Aug 23
Looking for highly motivated individuals who are keen to work on superconductivity in thin films of lanthanum nickelates. The project encompasses thin film growth by MBE, ARPES and STM. For the full advert, see www.vacancies.st-andrews.ac.uk/Vacancies/W/....
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henrylegg.bsky.social
Henry Legg @henrylegg.bsky.social · Aug 4
Apparently Microsoft are trying to patent their topological gap protocol.

In other news: I have decided to patent my protocol for optimising the number of angels that can dance on the head of a pin. It’s a real breakthrough for angel based quantum computing.
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