Particles of light

“Last year Google won international acclaim when its prototype quantum computer completed a calculation in minutes that its researchers estimated would have taken a supercomputer 10,000 years. That met the definition for quantum supremacy —the moment a quantum machine does something impractical for a conventional computer.

“Thursday, China’s leading quantum research group made its own declaration of quantum supremacy, in the journal Science. A system called Jiuzhang produced results in minutes calculated to take more than 2 billion years of effort by the world’s third-most-powerful supercomputer.

“The two systems work differently. Google builds quantum circuits using supercold, superconducting metal, while the team at University of Science and Technology of China, in Hefei, recorded its result by manipulating photons, particles of light.

[…]

“The potential power of quantum computers springs from their basic building blocks, dubbed qubits. Like the bits of conventional computers, they can represent 0s and 1s of data; but qubits can also exploit quantum mechanics to attain an unusual state called a superposition that encapsulates the possibilities of both. With enough qubits it’s possible to take computational shortcuts conventional computers can’t—an advantage that grows as more qubits work together.

“Quantum computers don’t yet rule the world, because engineers haven’t been able to get enough qubits working together reliably enough. The quantum mechanical effects they depend on are very delicate. Google and the Chinese group were able to stage their supremacy experiments because they managed to corral qubits in relatively large numbers.

“Google’s experiment used a superconducting chip dubbed Sycamore with 54 qubits, cooled to fractions of a degree above absolute zero. One qubit didn’t workbroke but the remaining 53 were enough to demonstrate supremacy over conventional computers on a carefully chosen statistical problem. It’s unclear just how many good quality qubits are needed for a quantum computer to do useful work; expert estimates range from hundreds to millions…”

Text: China Stakes Its Claim to Quantum Supremacy, Wired.

The Ruined Sky

“The astronomy community is on edge. The growing number of satellites streaming through low Earth orbit is making it almost impossible to get a clear view of the sky. 

“The true threat these mega-constellations pose to the astronomy community is only just beginning to be understood. A report released last week by the American Astronomical Society concluded that they will “fundamentally change astronomical observing” for optical and near-infrared investigations moving forward. “Nighttime images without the passage of a sun-illuminated satellite will no longer be the norm,” the authors write.

“The first Starlink satellites were already clearly visible shortly after launch  last year, and some observatories found their images of the night sky ruined. On Thursday, SpaceX is set to launch its latest batch of Starlink satellites, with a set of 60 to join the fleet of 653 that have been launched since May 2019. In a several years the entire network is expected to swell to 12,000 satellites, with a possible expansion to 42,000. London-based OneWeb […] just found FCC approval for 1,280 satellites to provide broadband services to US consumers, and the company is proposing a constellation that could eventually expand to 48,000 satellites. Amazon finally received approval for its Project Kuiper proposal to launch 3,236 satellites for its own satellite internet service, and this is likely just the beginning. Astronomy as we know it will never be the same.”

Text: Satellite mega-constellations risk ruining astronomy forever, MIT Technology Review

Pic: Hélio Oiticica, Metasquema 464, 1958.

From London to Rome

“The process, known as natural organic reduction, turns a corpse into two wheelbarrows’ worth of soil in four to six weeks. The body is placed in a reusable hexagonal steel container along with wood chips, alfalfa and straw. By carefully controlling the humidity and ratio of carbon dioxide, nitrogen and oxygen, the system creates the perfect conditions for a class of heat-loving (thermophilic) microbes that dramatically accelerate the normal rate of decomposition.

“It’s a bit of a surprise that when the microbial activity starts up and there’s enough feedstock, a whole different class of organisms, called thermophilic organisms, become active,” said Carpenter-Boggs.

“The pilot found that everything, including bones and teeth, is reliably transformed into compost (non-organic materials such as pacemakers and artificial hips are screened for and recycled). The soil was also found to contain low levels of coliform bacteria, an indicator of biological safety, meaning that relatives could safely scatter their loved ones’ remains like ashes, or use them to plant a rose bush or fertilise a vegetable patch.

“The process reportedly uses an eighth of the energy of cremation. According to Carpenter-Bogg, cremation in the US produces as much CO2 as burning 800,000 barrels of oil – for an individual, that is equivalent to taking a flight from London to Rome.”

Text: Hannah Devlin, Human composting could be the future of deathcare, Guardian UK.

Pic: Ricky Swallow, Younger Than Yesterday, 2006

Moving away from its home star…

“Maybe that’s why we’ve never heard a peep from anywhere. It’s not just that the universe is too big. Which it is. That’s the main reason. But then also, life is a planetary thing. It begins on a planet and is part of that planet. It’s something that water planets do, maybe. But it develops to live where it is. So it can only live there, because it evolved to live there. That’s its home. So, you know, Fermi’s paradox has its answer, which is this: by the time life gets smart enough to leave its planet, it’s too smart to want to go. Because it knows it won’t work. So it stays home. It enjoys its home. As why wouldn’t you? It doesn’t even bother to try to contact anyone else. Why would you? You’ll never hear back. So that’s my answer to the paradox. You can call it Euan’s Answer.” Later: “So, of course, every once in a while some particularly stupid form of life will try to break out and move away from its home star. I’m sure it happens. I mean, here we are. We did it ourselves. But it doesn’t work, and the life left living learns the lesson, and stops trying such a stupid thing.” Later: “Maybe some of them even make it back home. Hey—if I were you, Freya? I would try to get back home.” Later: “Maybe.” 

 Kim Stanley Robinson, Aurora.

“We do not know what the future will be…”

“It is a truism that we do not know what the future will be. But we can see trends. We do not know if the power of human ingenuity will help sufficiently to change the environmental trajectory we are on. Unfortunately, the recent years of innovation, investment and patenting indicate how human ingenuity has increasingly been channelled into consumerism and financial engineering. We might pray for time. But the evidence before us suggests that we are set for disruptive and uncontrollable levels of climate change, bringing starvation, destruction, migration, disease and war.

“We do not know for certain how disruptive the impacts of climate change will be or where will be most affected, especially as economic and social systems will respond in complex ways. But the evidence is mounting that the impacts will be catastrophic to our livelihoods and the societies that we live within. Our norms of behaviour, that we call our “civilisation,” may also degrade. When we contemplate this possibility, it can seem abstract. The words I ended the previous paragraph with may seem, subconsciously at least, to be describing a situation to feel sorry about as we witness scenes on TV or online.

But when I say starvation, destruction, migration, disease and war, I mean in your own life. With the power down, soon you wouldn’t have water coming out of your tap. You will depend on your neighbours for food and some warmth. You will become malnourished. You won’t know whether to stay or go. You will fear being violently killed before starving to death.

“These descriptions may seem overly dramatic. Some readers might consider them an unacademic form of writing. Which would be an interesting comment on why we even write at all. I chose the words above as an attempt to cut through the sense that this topic is purely theoretical. As we are considering here a situation where the publishers of this journal would no longer exist, the electricity to read its outputs won’t exist, and a profession to educate won’t exist, I think it time we break some of the conventions of this format. However, some of us may take pride in upholding the norms of the current society, even amidst collapse. Even though some of us might believe in the importance of maintaining norms of behaviour, as indicators of shared values, others will consider that the probability of collapse means that effort at reforming our current system is no longer the pragmatic choice. My conclusion to this situation has been that we need to expand our work on “sustainability” to consider how communities, countries and humanity can adapt to the coming troubles…”

Text: Jem Bendell, Deep Adaptation: A Map for Navigating Climate Tragedy

Image: Depiction of Hell, by Hieronymus Bosch