The instability of qubits stems from the way they rely on quantum properties such as superposition and entanglement to solve complex problems in fewer steps. Qubits can sift through vast numbers of possibilities using quantum inference to find solutions, but their natural state is extremely fragile. They can be disrupted all too easily, by microscopic defects in hardware, or even the slightest variation in heat, minuscule vibrations, electromagnetic interference or even cosmic rays.

That explains why existing quantum computers either run at temperatures close to absolute zero, or use novel technologies like lasers to manipulate ion-based qubits held in a vacuum, but while these techniques do help, they don’t completely solve the problem of instability.

By using quantum error correction systems, it’s possible to get around the instability problem by grouping multiple qubits into a single, logical qubit and performing regular consistency checks on them. It then becomes possible to identify logical qubits that deviate from the norm, and correct them when it happens.

The difficulty lies in spotting these errors, and that’s where AlphaQubit can help – Google DeepMind explains that it’s a neural network-based decoder that leverages the same transformer architecture that underpins many of today’s large language models. The team trained AlphaQubit on hundreds of consistency checks, so that it can correctly predict when a logical qubit starts behaving incorrectly.

As the researchers explained:

“We began by training our model to decode the data from a set of 49 qubits inside a Sycamore quantum processor, the central computational unit of the quantum computer. To teach AlphaQubit the general decoding problem, we used a quantum simulator to generate hundreds of millions of examples across a variety of settings and error levels. Then we tuned AlphaQubit for a specific decoding task by giving it thousands of experimental samples from a particular Sycamore processor.”

In the researchers’ tests, AlphaQubit displayed incredible accuracy compared to existing quantum decoders, making 6% fewer errors than tensor network methods in the largest Sycamore experiments. While tensor networks are quite accurate themselves, the problem is that they’re extremely slow. AlphaQubit, on the other hand, can identify errors with more accuracy and at much greater speed, more than fast enough to scale up to handle real-world quantum computing operations.

I just have a hard time imagining how one would convert a reactor like the NIF have (where tiny gold pellets of deuterium are loaded and blasted one at a time) into something which could power a city.

A tokamak like the JET or ITER (which can operate continuously) seems easier to adapt into a power plant.

The best material would be something thin and shiny like mylar, no?

That was an idea that once seemed promising for the ISS, via Bigelow Aerospace, but never seemed to go anywhere.

I bet we’ll see some inflatable modules on at least one of the upcoming commercial space stations. Sierra Space have continued testing where Bigelow left off.

They have something like the X-37 already.

Yup, the mysterious Shenlong spaceplane.

Dream Chaser from Temu

or that the idea of turning them off is simply inconceivable (why would I turn mine off and let others make money)

If that’s the issue, it seems like time-of-use rates or smart metering could be an easy solution. If the price of electricity were negative during periods of oversupply, I bet people would figure out how to disconnect their solar panels pretty quickly. This pricing model would simultaneously incentivize energy storage projects.

Passers-by are warned by a sign on each of Spot’s legs: “DO NOT PET.”

“I don’t know that anyone is tempted to pet these robot dogs. They do not look cuddly,”

Hey, every warning sign has a story.

I think their point was not that the grid should be abolished, but that when energy generation is decentralized, the grid becomes less susceptible to single points of failure.

One reason it’s so hard to make predictions about the fusion age is that we’re still not sure what the best fusion device will even look like. A tokamak, the doughnut-shaped machine Commonwealth is building? A giant laser, like Livermore Lab’s? Or one of the many other shapes and concepts that other start-ups are working on?

At this point, aren’t we pretty sure that laser confinement won’t easily scale to continuous operations? All the fusion startups I can think of are using some form of magnetic confinement.

billion kilowatt-hours

A.k.a. terawatt-hours? It always irks me when people mix SI prefixes with 'illions.

Eastport, Maine

Neural, I think?

This seems like a good problem to have, no? Just need some batteries or some interruptible industrial processes to absorb the excess.

The numbers for what is considered UHV:

Different countries have different thresholds for what is considered a UHV line. China defines those sending direct currents (DC) at voltage levels of 800 kilovolts (kV) or above and alternating currents (AC) at 1,000 kV or above as UHV links.

Always exciting to see new electrical infrastructure.

He details how we can use quirks of lunar gravity to use a mass driver to send passive loads to lunar orbit, where they can then be picked up with active, high-efficiency systems and sent elsewhere in the solar system for processing.

Anomalies in the Moon’s gravitational field have been known for some time. Typically, mission planners view them as a nuisance to be avoided, as they can cause satellite orbits to degrade more quickly than expected by nice, simple models. However, according to Dr. Janhunen, they could also be a help rather than a hindrance.

This satellite mapped the Moon’s gravity in great detail and found several places on the lunar surface where a mass driver could potentially launch a passive payload into an orbit that would last up to nine days.

Huh, so I’m understanding it correctly, it might be possible for the lumpy lunar gravitational field to circularize an orbit in lieu of an upper stage. Seems pretty nifty.

Despite the political turmoil, I’d say the likelihood is still low.