A Second Way to Build a Topological Qubit, and It Runs on Hardware Already Available

Chapter 10 of Quantum from the Ground Up tells one story about topological qubits: Microsoft growing an exotic nanowire material to host a particle called a Majorana zero mode. That approach needs new physics and new materials, and it has been slow going. A team at Quantinuum, working with researchers at Harvard, UChicago, and Stony Brook University, just showed a different way to get the same protection against errors. They published the result in Nature.

Here is the paper describing a universal topological gate set built from braiding and fusing exotic particles called anyons. They did not grow anything new. They took an ordinary trapped-ion quantum computer, Quantinuum's H2, and used 54 of its regular qubits to build a state of matter that behaves the way the exotic Majorana material is supposed to behave.

Start with what an anyon is. In everyday physics, particles come in two types: fermions, like electrons, and bosons, like photons. Anyons are not fundamental particles. They only show up inside certain engineered quantum systems, as patterns in how a group of qubits is entangled together. The interesting kind here are called non-Abelian anyons. If you take two of them and swap their positions, then swap two more in a different order, you get a different final result depending on which order you did the swapping in.

That sounds like a technicality, but it is the whole point. Because the result depends on the order of the swaps and not on small local wobbles or noise, information stored this way is naturally protected. Physicists call the swapping process braiding, since tracking two anyons moving around each other looks like braiding two strands of hair. In the diagram below, a1 passes in front of a2, shown by the small break in a2's line where it crosses behind. Swap them the other way, with a2 in front instead, and the anyons end up in a different state. Which one passes in front is not a drawing choice. It is the physical information the braid records.

Braiding by itself has a known gap. Researchers proved back in a 2003 proposal from physicist Carlos Mochon that for the simplest type of non-Abelian anyons, braiding alone cannot give you every operation a computer needs. You can protect information this way, but you cannot fully compute with it. Something was missing.

The Quantinuum team's answer was to add a second move: fusion. Instead of only moving anyons around each other, they also merge two anyons together and measure what comes out. Braiding plus fusion turns out to supply the missing operations, creating a mathematically complete set of gates capable of running any algorithm.

They built a 54-qubit state based on a mathematical structure called S₃—the smallest group that produces non-Abelian anyons—then stored information in the combined fusion outcomes of many anyons taken together rather than in any single qubit. Each unit of stored information could hold three states instead of the usual two (a qutrit rather than a qubit), since these anyons naturally support three possible fusion outcomes. Using braiding and fusion together, the team ran a computationally universal set of operations and read out the result correctly.

As a real test, they used the setup to build what is called a magic state, a specific resource that most fault-tolerant quantum computing schemes need. Normally, generating that resource requires an expensive extra process called magic state distillation, which eats up huge numbers of physical qubits just to produce one clean logical one. This approach made the same resource directly via topological operations without that extra step.

What This Changes in the Book

Chapter 10 needs a second section. Microsoft and Quantinuum are both chasing the same goal—a qubit that resists errors because of its shape rather than because of constant correction—but they are getting there in different ways. Microsoft is trying to grow a new material that hosts the right kind of particle directly. Quantinuum instead uses software and precise control to make an ordinary quantum computer behave as if that exotic material were there.

Chapter 6 gets an update too. The H2 processor was already in the book because of its record for entangling 56 qubits at once. Now it has a second claim to fame: it is a working testbed for this kind of engineered, error-resistant state of matter.

Neither team has built an actively error-corrected logical qubit that outperforms physical hardware yet. Both just found a more believable road toward one—and it turns out you do not need exotic new hardware to try.

This post will roll into the next edition, due September 1. The current edition is free at gordostuff.com/p/quantum-from-ground-up-hardware.html

Why Quantum Computing Matters, Even If You Never Touch One

I logged into my bank app last week to move some money to pay some bills. A padlock icon appeared next to the address bar. Secure connection. I didn't think about it again. Somewhere, someone already has a copy of that session, sitting on a hard drive, waiting.

That padlock runs on a math problem: factor a huge number into its two prime components. A classical computer needs longer than the age of the universe to do that. A large enough quantum computer, running an algorithm built for exactly this job, does it in hours. That computer does not exist yet. It is being built right now, funded by billions of dollars, and no government or company controlling that funding will announce the day it works.

You do not get to wait for that announcement. Security researchers call the attack already underway harvest now, decrypt later. Think about what you have touched on the web this year: your bank, your medical portal, your voter registration, your immigration or legal filings, your tax return, your cloud photo backup. State-backed intelligence services and criminal groups are copying that same traffic from millions of other people today, and storing it cheaply. Almost none of it needs to be cracked now. It needs to still exist, on somebody's drive, the day a quantum computer catches up. Then all of it becomes readable at once.

NIST finalized three new encryption standards built to resist this and set 2035 as the deadline to retire the vulnerable ones. Cloudflare and Google are not waiting until then; they have committed to migrating by 2029. Banks, hospitals, and government agencies holding decades-long records are moving faster still, because for them the clock already ran out on some of what they are protecting.

The fix is not a patch on the old method. It replaces the math underneath it. Government researchers finalized a new set of encryption methods built to survive a quantum computer, the same way today's methods survive an ordinary one. Companies are not waiting to switch over all at once, either. Cloudflare, Google, and Apple already run two locks on the same connection at the same time: the old one and the new one. If someone finds a weakness in the new lock, the old one still holds. If a quantum computer breaks the old lock, the new one still holds. Traffic protected this way stops being worth harvesting, because breaking one lock alone gets an attacker nothing.

Getting every bank, hospital, and government agency onto the new locks is the slow part. It means finding every place the old encryption sits inside a system and replacing it without breaking what depends on it. The federal government has published a shared plan for doing exactly that, across every agency and industry. None of it requires anything from you. It happens inside the apps and websites you already use.

The fix only protects what gets encrypted after it is installed, though. Anything copied under the old lock before that happens is already sitting on somebody's drive, and nothing reverses that. New encryption prevents future harvesting. It does not undo what has already been taken.

Diagram claude.ai generated

Nothing solves the data that is already sitting on somebody's drive. There is no way to reach into another party's storage, revoke a copy, or make it unreadable again. The new locks protect what gets encrypted after they are installed. They have no effect on a copy that left your device years earlier.

How much that matters depends on what kind of data it is. A password can be changed after the fact, so a stolen password loses most of its value once you reset it. A medical record, a Social Security number, or a biometric scan cannot be changed. Whatever gets exposed on that front stays exposed for good. It also depends on how long the data needed to stay private in the first place. Something that only mattered for a few years is probably already safe by the time a quantum computer shows up. Something that needed to stay private for decades, a government file, a company's trade secrets, a hospital's records, is running on a clock that started the day it was copied, not the day the quantum computer arrives.

Most people are not personally worth the effort. A patient attacker spends storage on high-value targets: government communications, corporate research, hospital systems, banks. If you end up exposed, it is more likely through one of those institutions holding your data than through anyone singling you out.

There is not much a consumer can do about data that is already gone. A few things still help:

•   Rotate what can be rotated. Change passwords regularly. A password manager makes it cheap enough to do more than once.

•   Turn on two-factor authentication. It stops a harvested password from being enough to log in on its own, since an attacker also needs your phone, an authenticator app, or a security key. It does not protect the data itself. A hospital record, a legal filing, or an old email that already left your device is untouched by it, because it only fires at login, not on the traffic that carries the data.

•   Not every two-factor method is equal. A text message code can be intercepted or rerouted if someone tricks your phone carrier into moving your number to a new SIM. An authenticator app is safer, since the code generates on your phone instead of traveling over the phone network. A hardware security key is safer still, a small physical device that checks a site's real address before it responds, so it does not work on a convincing fake login page. Use one for your email, your bank, and your password manager itself.

•   Assume what cannot be rotated is already out. Watch for misuse instead of trying to prevent something that may have already happened. A credit freeze and fraud alerts catch someone using a stolen Social Security number long before you would otherwise notice.

•   Keep your software current. The new locks only work if your browser, phone, and apps are recent enough to use them. An old browser is still running the old lock alone.

•   Think twice about what you put online today. Anything sent through email, cloud storage, or a messaging app now can still be harvested under the old lock until your provider finishes switching over.

•   Ask the institutions holding your data. A bank or hospital's own migration timeline affects your exposure more than anything you do personally, and it is a fair question to put to them directly.

None of it undoes what has already been copied. It limits what is still worth harvesting and reduces the damage from what is not.

The padlock on my banking app will look exactly the same through all of this. Behind it, the locks are being swapped one at a time: bank by bank, cloud provider by cloud provider. The question left is not whether the new lock exists. It is how much of your data got copied before it arrived.

Proving Ownership After Q-Day: Project Eleven's Wallet Recovery Proof Reaches Beyond Bitcoin

Chapter 13 of Quantum from the Ground Up covers the Q-Day timeline: Google researcher Craig Gidney's 2025 estimate of roughly one million physical qubits to break RSA-2048, and the IonQ fidelity result that pulled some estimates into a 2029 to 2033 window. That chapter treats Q-Day as an encryption problem: once a quantum computer can derive a private key from a public key, the signature scheme securing a wallet fails. A proposal from the security firm Project Eleven treats it as an ownership problem instead, and the distinction matters for anyone holding funds in an address generated before a migration to quantum-safe cryptography. The July 16 announcement was framed around Bitcoin, but the mechanism targets any wallet built on BIP-32-style hierarchical derivation, which includes Ethereum and other ECDSA chains, not Bitcoin alone.

The failure mode is simple. A wallet proves ownership by signature: if you can sign a transaction with the private key tied to an address, the network accepts you as the owner. Once elliptic-curve cryptography breaks, an attacker holding your address's public key can derive the same private key and produce a signature the network cannot tell apart from yours. Ownership by signature stops meaning anything. Project Eleven CEO Alex Pruden framed the central problem as proving who owns a wallet once quantum attacks become possible, not just stopping the attack, which is the framing this post follows.

Project Eleven's fix works one level up the derivation tree. Most wallets generate addresses from a BIP-39 seed phrase, the standard list of words a wallet gives you at setup, through a hierarchical, hardened derivation path. This structural proof builds on a concept known as signature lifting—originally described by researchers Alon Sattath and Robert Wyborski—and is implemented here as a form of cryptographic lineage verification. Breaking the elliptic-curve key at the address level does not hand an attacker the parent key higher up that path, because the hardened derivation step runs through a hash function, not an elliptic-curve operation. A zero-knowledge proof lets the real owner demonstrate control of that parent key, and that it derives the compromised address, without exposing the key itself. An attacker who has only broken the address-level key cannot produce the same proof.

Jim Posen, lead maintainer of the Binius zero-knowledge proof system, built the implementation with Project Eleven's funding. The resulting Binius-based prover clocks a generation time of just 243 milliseconds on a standard laptop—over 200 times faster than the 55-second benchmark set by Olaoluwa Osuntokun’s unoptimized, CPU-based prototype earlier this year. It is exactly the kind of radical performance leap, driven by Binius's optimization for hash-heavy operations, that turns an academic curiosity into something ready for deployment.

Diagram Gemini generated

None of this is available on any chain today. Project Eleven describes the release as an unaudited prototype that needs explicit protocol-level support, or a dedicated verifier, before any chain could use it for recovery. It also only applies to wallets built on compatible BIP-32-style derivation, which rules out addresses whose provenance was never recorded as a reproducible path. The stakes for getting a recovery layer right are not small: Coinbase's quantum advisory board warned in June that roughly seven million bitcoins are at risk of being stranded without a post-quantum transition.

The technique also does not generalize evenly across chains. Solana, Sui, Aptos, Near, and Stellar derive signing keys from a seed through a single hashing scheme defined at the protocol level, so one proof design covers every wallet on those chains the same way. Bitcoin and Ethereum have no such uniform scheme; wallet software implements BIP-32 derivation its own way, so each wallet family needs its own proof circuit. That is a real engineering cost, and it is why Project Eleven's Bitcoin result is a first case rather than a finished product.

What This Changes in the Book

Chapter 14 already tracks how far post-quantum migration has actually spread: 21.9 percent of the top 1,000 sites, 8.4 percent of the top 100,000, and 3 percent of banking sites had adopted PQC software as of the last edition. Those numbers describe a migration that will not finish on schedule for everyone. The book's framing up to now has been prevention: move assets and systems to quantum-resistant cryptography before Q-Day arrives. Project Eleven's proposal is the first credible recovery mechanism I've seen for the users, custodians, and exchanges who miss that window, and it is not tied to one chain. The next edition's Chapter 14 will add a paragraph on derivation-based recovery proofs as a fallback layer, noting that EdDSA chains get a uniform version of this fix while Bitcoin and Ethereum need it built wallet by wallet.

This post will fold into the September 1 edition of Quantum from the Ground Up. The current edition is available at https://gordostuff.com/p/quantum-from-ground-up-hardware.html 

Quantum Keys Move Onto Production Routers

Quantum Keys Move Onto Production Routers

I led the telecommunications curriculum for Verizon's Next Step New England program and directed National Science Foundation, or NSF, funded Centers of Excellence at Springfield Technical Community College and the University of Central Florida through the transition from my Dad's Plain Old Telephone Service, or POTS, landlines to Internet Protocol, or IP, based voice, video, and data over copper, fiber and wireless. Our center worked closely with Cisco through that transition. The physics and the protocols changed rapidly snd it was a wild ride. What made the transition real was not the standards documents. It was carriers running the new transport on switches and routers in the central office, and technicians who did not need an advanced degree to keep it running.

Quantum key distribution, or QKD, is a way to generate an encryption key using the behavior of individual photons instead of math. Two machines exchange specially prepared light particles over fiber. If anyone taps the line and looks at those particles, the particles change in a way both ends can detect. That gives you a key exchange where eavesdropping does not stay hidden, which is a different from anything conventional encryption offers.

Aliro Technologies, the Vienna based quantum networking firm zerothird, and Cisco just ran a live version of this over Cisco's production routers at Cisco's Photonics Center in Vimercate, Italy. The hardware was Cisco's 8000 Series routers, the same platform Cisco sells into data centers today. That detail is the news. QKD has existed in labs for years. Running it on hardware a customer can already buy is the harder problem.

The system runs on the BBM92 protocol, which uses paired entangled photons rather than a transmitted key to establish a shared secret. Entangled photons are pairs of light particles created together so that measuring one instantly tells you something about the other, no matter the distance between them. A source creates these pairs and sends one photon from each pair to each end of the link. Both ends measure what arrives and use those measurements to build an identical key, without the key itself ever traveling across the fiber. zerothird supplies the hardware that does this: the photon source, the equipment that keeps the light polarized correctly, synchronizing clocks, and the software that cleans up errors and strengthens the final key. Aliro's Orchestrator software sits on top and manages the link, the way network management software already watches a conventional router. It tracks error rates and photon counts in real time and can reroute traffic or shut a link down safely if something looks wrong. The finished keys reach the routers through Cisco's Secure Key Integration Protocol, a standard interface, where they secure encrypted sessions between routers the same way a conventional key would, just generated a different way.

Diagram Gemini AI Generated

Chapter 1 of Quantum from the Ground Up covers the fiber problem in quantum networking through the University of Illinois work on ytterbium-171 emitters built for existing telecom infrastructure. That chapter is about getting a quantum signal onto fiber that already exists. This deployment answers the other half of the problem: getting the output of that signal into a router that already exists, with the monitoring and failover a network operations center can actually run day to day.

Chapter 14 frames quantum security as a race between two approaches. Post quantum cryptography, or PQC, keeps using math for encryption, just math that a quantum computer cannot easily break, and the National Institute of Standards and Technology, or NIST, has already published standards for it. QKD, the approach in this demonstration, does not rely on hard math at all. It relies on physics: any attempt to intercept the entangled photons changes them in a way both ends can detect. That is also its limit. A QKD key only protects the specific fiber link between two endpoints, while PQC can protect data anywhere the software runs. That is why Cisco is running both approaches rather than picking one. AT&T's coming quantum resilient Software-Defined Wide Area Network, or SD-WAN, service runs PQC on that same 8000 Series router line, which puts both approaches on the same hardware within the same product family.

The public announcement described the deployment as moving QKD out of isolated research setups and into standard enterprise infrastructure. Coverage of the announcement also framed the three way pairing as proof that quantum networking gear from separate vendors can interoperate in a live deployment, which matters more for enterprise adoption than any single performance number. A separate technical paper from the zerothird team tested the same entanglement based approach over a 22 kilometer fiber link between two data centers, which gives the enterprise demonstration a research paper trail worth reading alongside the press coverage.

What This Changes in the Book

Chapter 1 currently ends at the physics of getting quantum signals onto standard fiber. This deployment extends that story into the network operations layer: orchestration, telemetry, and automated remediation running on hardware already shipping. Chapter 14's framing of PQC and QKD as separate paths still holds, but the AT&T and Cisco pairing on the same 8000 Series router line is worth adding as a concrete case where one operator runs both approaches at once instead of choosing sides.

This post will fold into the next edition of the book, due September 1. The current edition is at gordostuff.com/p/quantum-from-ground-up-hardware.html.

POTS to IP took a decade of this kind of work: new transport riding on racked equipment. Quantum key distribution is passing the same tesst. The obstacle was never the physics. Here it's whether the keys can ride on a router Cisco already sells, watched by software a network operations center knows how to run.

Where the Jobs Actually Are

Some graduates spent the 2026 commencement season blaming AI for a job market that shut them out, loud enough that tech executives got booed at graduation ceremonies over it. Recruiters tell a different story.

Matt Walsh, CEO of the Phoenix search firm Blue Signal, works semiconductor hiring daily and says the problem isn't automation. "There aren't enough people," he says. The United States is heading toward what labor economists call the largest workforce shortage in its history, and it shows up hardest in the fields that build things.

The semiconductor industry expects to add close to 115,000 jobs by 2030. The Semiconductor Industry Association projects a shortfall of 67,000 technicians and engineers to fill them. That gap sits squarely in associate degree and bachelor's degree technical programs, not in the AI research labs getting most of the headlines.

Construction and the skilled trades show the same pattern. Branka Minic, CEO of the Building Talent Foundation, says fewer than half the workers needed in construction are entering the field, even with starting wages hitting $50 an hour in some markets. College graduates aren't matching that pay in comparable years of training.

Cybersecurity tells a similar story. CyberSeek, the workforce tracker built by CompTIA and NIST, counts hundreds of thousands of open cybersecurity positions in the U.S. against a supply of qualified workers that consistently falls short. The roles span network defense, security operations, and incident response, and they don't require a computer science PhD. A two-year degree with the right certifications gets a candidate into the field.

This is good news if you're building a technical career instead of chasing a headline. Employers in semiconductors, cybersecurity, advanced manufacturing, robotics, and skilled trades are competing for candidates, not filtering through thousands of applicants for one opening. Two-year technical programs, apprenticeships, internships and engineering degrees put graduates directly into that competition.

States have noticed too: several are merging workforce and higher education agencies or offering loan payoff incentives to pull people into these pipelines.

The AI panic makes for a cleaner headline than a demographic and skills pipeline problem. But the demand for people who can build, install, test, and maintain physical systems is not shrinking. It's the part of the labor market with the fewest applicants and the most openings.

ETH Zurich Builds Quantum RAM Out of Vibrations

Chapter 5 of Quantum From The Ground Up covers superconducting qubits by way of Josephson junction fabrication and IBM's 1,121-qubit Condor chip. It never had to answer a basic architecture question: where a superconducting qubit puts its data when it isn't actively working on it. Researchers at ETH Zurich just built an answer, and it doesn't look anything like a normal memory chip.

A team led by physicist Yiwen Chu, head of ETH Zurich's Hybrid Quantum Systems Group, split a quantum computer into the same two roles a laptop uses: a processor and a separate working memory. The design uses a superconducting transmon qubit as the processor and a mechanical resonator as memory, on a chip package 7.5 millimeters long. Instead of storing a qubit's state electromagnetically, the resonator holds it as a mechanical vibration, the way a guitar string holds a note, except this vibration follows quantum rules rather than classical ones.

Each resonator supports several distinct vibrational modes, and each mode works as its own memory slot. To run a computation, the qubit reaches into the resonator, pulls out a stored vibration, modifies it, and writes it back. Doctoral students Yu Yang and Igor Kladarić built the hybrid chip alongside Chu. The team validated the architecture by running a Quantum Fourier Transform and a period-finding algorithm on the hybrid chip, published in Science. That marks the first demonstration of mechanical resonators executing real quantum algorithms rather than just holding a state.

Superconducting qubits pack in tightly, but that density crowds out room for data. Electromagnetic memory schemes have historically traded a smaller footprint against coherence time. Mechanical resonators split that trade differently, offering higher storage density and longer coherence in less physical space. the approach still has to prove it scales beyond a single test chip, and Chu's group is continuing the work with that goal in mind.

What This Changes in the Book

Chapter 5's numbers don't move. IBM's Condor still holds at 1,121 qubits and 99.0 to 99.5 percent two-qubit fidelity, and nothing here challenges either figure. What changes is the chapter's scope. Chu's result adds a memory subsystem to the superconducting platform, a second engineering problem the chapter didn't previously address. It's a proof of principle, not a shipped component. A chip built for one qubit and one resonator still has to prove itself when both categories multiply.

This post will fold into the next edition of Quantum from the Ground Up, due September 1. The current edition is free to read at gordostuff.com/p/quantum-from-ground-up-hardware.html, and if it's useful to you, a coffee at ko-fi.com/gordostuff keeps it updated.

Dad and Doug

Lost my father and a close friend, Doug, within months of each other last year. Dad was fine right up until the last few weeks. Doug had been fighting for about five years. I wrote about each of them here already (for Dad, and for Doug), but never posted the obituaries themselves.

This blog has been mostly tech since 2005. But some things need to get written down while I still can, and this is one of them. Miss them both.

Write things down while people are still around to read them. The obituary is the last thing anyone writes about most of us. Everything before it is still yours to say.