… but I’ve started to wonder if we’re missing something in the course of expressing opinions about what we thought climate deniers would say and what they’re actually saying. That is, we expected to be right about what we thought they’d say but we’ve found ourselves wrong. Should we lampoon ourselves as well? Or, to reword the cartoon:
How we imagined we could react when ‘what we imagined deniers would say when the climate catastrophes came’ came true: “I was so right! And now everyone must pay for their greed and lies! May god have mercy on their soul!”
Followed by:
How we expect we’ll react when we find out ‘what they actually are saying’: “I was so wrong! And now everyone must pay for my myopia and echo chambers! May god have mercy on my soul!”
And finally:
How we actually are reacting: “We’re just using these disasters as an excuse to talk about climate change! Like we did with COVID! And 9/11! And the real moon landings! Screw you and your federal rescue money! You need to take your electric vegan soy beans now!”
People (myself included) in general aren’t entirely effective at changing others’ attitudes so it may not seem fair to say there’s a mistake in us not having anticipated how the deniers would react, that we erred by stopping short of understanding really why climate denialism exists and addressing its root cause. But surely the latter sounds reasonable in hindsight? ‘Us versus them’ narratives like the one in the cartoon describe apparent facts very well but they also reveal a tendency, either on the part of ‘us’ or of ‘them’ but often of both, to sustain this divide instead of narrowing it.
I’m not ignorant of the refusal of some people to change their mind under any circumstances. But even if we couldn’t have prevented their cynical attitudes on social issues — and consensus on climate change is one — maybe we can do better to anticipate them.
Yesterday, July 25, was a big day. Ironhide Games released the long-awaited fifth edition of their tower-defence game ‘Kingdom Rush’. I bought it as soon as it launched and completed its primary campaign in one sitting of several hours. Called ‘Alliance’, the game combines the gameplay of ‘Kingdom Rush: Vengeance’ and Ironhide’s ‘Junkworld’, together with aspects of ‘Legends of Kingdom Rush’. The game also continues a long storyline that began with the first ‘Kingdom Rush’ game, released in 2011, and last updated in ‘Vengeance’. For what it’s worth, it’s a good story, too.
In ‘Kingdom Rush: Origins’, Ironhide introduced Vez’nan as a powerful wizard who becomes corrupted by a gem called the Tear of Elynie to become a malevolent power threatening the kingdom of Linirea. In the games that followed, heroes and towers from several parts of the kingdom, ultimately including King Denas, were tasked with defeating Vez’nan and his allies. In ‘Vengeance’, Vez’nan returned to exact revenge against King Denas — or so it seemed. ‘Alliance’ describes Denas’s return as well as Vez’nan’s efforts against a greater evil called the Overseer, who is also the ultimate boss in ‘Legends of Kingdom Rush’.
A ‘Kingdom Rush: Alliance’ skirmish begins…
I love tower-defence games and among them ‘Kingdom Rush’ is my favourite by far. I own all editions of it as well as have unlocked most towers and heroes in each one. At more than a few points during a work day, I like to break one of these games out for a quick and hairy skirmish or — time permitting — a full-on campaign on a high difficulty setting.
But while I like to play as often as I can, tower-defence doesn’t fit all moods. I have 13 games on my phone: the five ‘Kingdom Rush’ games, ‘Junkworld’, ‘Monument Valley’ I and II (and the expansion packs), ‘Loop’, ‘1010!’, ‘Idle Slayer’, ‘Rytmos’, and ‘Lost in Play’. They’re all great but I’d single out ‘Idle Slayer’, ‘Loop’, and ‘Monument Valley’ for particular praise.
‘Idle Slayer’ is a top-notch incremental game (a.k.a. idle game): the game will continue irrespective of whether you interact with the player-character, the player-character can’t perish, and gameplay is restricted to tapping on the screen to make the character jump. The whole point is to slay monsters — which the character will if she/flies runs into them, automatically pulling out an omnipotent sword when she gets close — and collect slayer points and to pick up coins and gems, which the character also does if she runs/flies into them. ‘Idle Slayer’ thus eliminates the player (you, me, etc.) having to be challenged in order to reap rewards. It’s just a matter of time, although occasional bursts of speed and character abilities purchased with slayer points can make things exciting.
I agree with what journalist Justin Davis wrote in 2013:
“Idle games seem perfectly tuned to provide a never-ending sense of escalation. They’re intoxicating because upgrades or items that used to seem impossibly expensive or out of reach rapidly become achievable, and then trivial. It’s all in your rearview mirror before you know it, with a new set of crazy-expensive upgrades ahead. The games are tuned to make you feel both powerful and weak, all at once. They thrive on an addictive feeling of exponential progress.”
Right now, this is where I’m at: 209 decillion coins in my kitty and racking up 110 octillion coins per second, plus whatever I pick up as I keep running…
My player-character is named Mintana. She’s awesome.
Second is the amazing ‘Loop’, an endless series of puzzles in each of which your task is to link up some open-ended elements on a screen such that they form a large closed loop. You can tap on each element to rotate it; when the open ends of two elements line up in this way, they link up. The game is minimalist: each level has a plain monotone background and elements of a contrasting colour, and there’s beautiful, low-key instrumental music to accompany your thoughts. ‘Loop’ is the game to get lost in. I’ve played more than 3,500 levels so far and look forward every day to the next one.
The two rings in the bottom-left corner are linked up.
Third comes ‘Monument Valley’, but in no particular order because it’s the game I love the most. I don’t play it as often as I play ‘Kingdom Rush’, ‘Idle Slayer’ or ‘Loop’ because its repeatability is low — but it’s the game that redefined for a younger and less imaginative me what a smartphone product could look and feel like when you play it. ‘Monument Valley’ is an ode to the work of the Dutch artist MC Escher, famed for his depiction of impossible objects that toy with the peculiarities of human visual perception. The player-character is a young lady named Ida navigating a foreboding but also enchanting realm whose structures and vistas are guided by the precepts of a mysterious “sacred geometry”. The game’s visuals are just stunning and, as with ‘Loop’, there’s beautiful music to go with. The objects on the screen whose geometries you change to create previously impossible paths for Ida take time to move around, which means you can’t rush through levels. You have to wait, and you have to watch. And ‘Monument Valley’ makes that a pleasure to do.
Unobtrusive pink, lush green, obsidian black.
It should be clear by now that I love puzzles, and ‘1010!’ is perhaps the most clinical of the lot. It’s Tetris in pieces: you have a 10 x 10 grid of cells that you can fill with shapes that the game presents to you in sets of three. Once you’ve placed all three on the grid, you get the next three; once a row or a column is filled with cells, it empties itself; and once you can no longer fit new shapes in the grid, it’s game over. ‘1010!’ takes up very little of your cognitive bandwidth, which means you have something to do that distracts you enough to keep you from feeling restless while allowing you to think about something more important at the same time.
What does losing mean if you can never win?
‘Rytmos’ and ‘Lost in Play’ are fairly new: I installed them a couple weeks ago. ‘Rytmos’ is just a smidge like ‘Loop’ but richer with details and, indeed, knowledge. You link up some nodes on a board in a closed loop; each node is a musical instrument that, when it becomes part of the loop, plays a beat depending on its position. Suddenly you’re making music. There are multiple ‘planets’ in the game and each one has multiple puzzles involving specific instruments. You learn something and you feel good about it. It’s amazing. I’ve only played a few minutes of ‘Lost in Play’ thus far, and I’m looking forward to more because it seems to be of a piece with ‘Monument Valley’, from the forced-slow gameplay to the captivating visuals.
A scene from ‘Lost in Play’.
Aside from these games, I also play ‘Entanglement’ in the browser and ‘Factorio’ on my laptop. ‘Factorio’ is the motherlode, an absolute beast of a game for compulsive puzzle-solvers. In the game, you’re an engineer in the future who’s crash-landed on an alien planet and you need to build a rocket to get off of it. The gameplay is centred on factories, where you craft the various pieces required for more and more sophisticated components. In parallel, you mine metals, pump crude oil, extract uranium, and dig up coal; you smelt, refine, and burn them to get the parts required to build as well as feed the factories; you conduct research to develop and enhance automation, robotics, rocketry, and weapons; you build power plants and transmission lines, and deal with enormous quantities of waste; and you defend your base from the planet’s native life, a lone species of large, termite-like creatures.
I’ve been playing a single game for three years now. There’s no end in sight. Sometimes, when ‘Factorio’ leaves me enough of my brain to think about other things, I gaze with longing as if out of a small window at a world that has long passed me by…
[Polyphonic robot voice] This facility mines copper ore, smelts it to copper plates, and feeds it to factories that make copper cables.
Agalloch is a synonym of agarwood. In parallel, Aquilaria agallocha and Agalochum malaccense are synonyms of Aquilaria malaccensis, the accepted scientific name of a tree that produces much of the world’s stock of this wood. When the heartwood (or duramen) of an Aquilaria tree is in the grip of an infection of Phaeoacremonium parasitica, the tree secretes a resin to beat the fungus off. The resin is very fragrant; depending on the duration of secretion, the heartwood can become saturated with it, at which point it becomes the very odoriferous agarwood. For centuries people have extracted this agarwood for use in perfumes and incense. We have also found the oils extracted from the wood, especially using steam distillation of late, are chemically very complex, including more than 70 terpenoids and more than 150 compounds overall.
This is a fascinating tale for the origin of something beautiful in nature, prompted by a tree’s desperate bid to fight off the advance of a fungal menace. Of course the human beholds this beauty, not the tree and certainly not the fungus — and Aquilaria malaccensis‘s wondrous resin hasn’t been able to keep humans at bay. The tree is listed as being ‘critically endangered’ on the IUCN Red List thanks to habitat loss and improper management of the global demand for the resinous agalloch.
From ‘ASI submits Bhojshala survey report to Madhya Pradesh High Court’, The Hindu, July 15, 2024:
The Archaeological Survey of India (ASI) on July 15 submitted its scientific survey report of the disputed Bhojshala-Kamal-Maula mosque complex to the Indore Bench of the Madhya Pradesh High Court. … On July 4, the High Court ordered the ASI to present by July 15 the complete report of the nearly three-month-long survey on the premises of the disputed 11th-century monument, the subject of a wrangle between Hindus and Muslims. The Hindu community considers Bhojshala as a temple of Vagdevi (Goddess Saraswati), while the Muslim side calls it Kamal Maula mosque. The HC on March 11 ordered the ASI … to conduct a scientific survey of the complex … It then gave six weeks to the ASI to complete the survey. The ASI later sought more time for the report submission. The ASI began surveying the disputed complex on March 22 which ended recently.
Isn’t it cynical of ASI to engage in these exercises? New structures will often be built on old ones. But undertaking a study, then preparing a study is just disingenuous. It is also disingenuous to appeal to science to settle questions that are otherwise devoid of reason. I wish history scholars and scientists spoke up more vociferously on this instead of engaging in this charade. It’s practically why a separate nodal agency of archaeological study and deliberation exists, and not to be a mute provider of ‘archaeological services’ when called upon…
In a conversation with science journalist Nandita Jayaraj, physicist and Nobel laureate Takaaki Kajita touched on the dismal anti-parallels between the India-based Neutrino Observatory (INO) and the Japanese Kamioka and Super-Kamiokande observatories. The INO’s story should be familiar to readers of this blog: a team of physicists led by those from IMSc Chennai and TIFR Mumbai conceived of the INO, identified places around India where it could be built, finalised a spot in Theni (in Tamil Nadu), and received Rs 1,350 crore from the Union government for it, only for the project to not progress a significant distance past this point.
Nandita’s article, published in The Hindu on July 14, touches on two reasons the project was stalled: “adverse environmental impacts” and “the fear of radioactivity”. These were certainly important reasons but they’re also symptoms of two deeper causes: distrust of the Department of Atomic Energy (DAE) and some naïvety on the scientists’ part. The article mentions the “adverse environmental impacts” only once while “the fear of radioactivity” receives a longer rebuttal — which is understandable because the former has a longer history and there’s a word limit. It bears repeating, however.
Even before work on the INO neared its beginning, people on the ground in the area were tense over the newly erected PUSHEP hydroelectric project. Environmental activists were on edge because the project was happening under the aegis of the DAE, a department notorious for its opacity and heavy-handed response to opposition. The INO collaboration compounded the distrust when hearings over a writ petition Marumalarchi Dravida Munnetra Kazhagam chief Vaiko filed in the Madras high court revealed the final ecological assessment report of the project had been prepared by the Salim Ali Centre for Ornithology and Natural History (SACON), which as the law required at the time hadn’t been accredited by the Quality Council of India and was thus unfit to draft the report. Members of the INO collaboration said this shouldn’t matter because they had submitted the report themselves together with a ‘detailed project report’ prepared by TANGEDCO and a geotechnical report by the Geological Survey of India. Perhaps the scientists thought SACON was good enough, and it may well have been, but it’s not clear how submitting the report themselves should have warranted a break from the law. Given all the other roadblocks in the project’s way, this trip-up in hindsight seems to have been a major turning point.
Locals in the area around the hill, under which the INO was to be built, were also nervous about losing access to part of their grazing land and to a temple situated nearby. There was a report in 2015 that police personnel had blocked people from celebrating a festival at this temple. In an April 2015 interview with Frontline, when told that local police were also keeping herders from accessing pastureland in the foothills, INO spokesperson Naba Mondal said: “The only land belonging to INO is the 26.825 ha. INO has no interest in and no desire to block the grazing lands outside this area. In fact, these issues were discussed in great detail in a public meeting held in July 2010, clearly telling the local people this. This is recorded in our FAQ. This was also conveyed to them in Tamil.” In response to a subsequent question about “propaganda” that the project site would store nuclear waste from Tamil Nadu’s two nuclear power facilities, Mondal said: “The DAE has already issued a press statement in this regard. I do genuinely believe that this has allayed people’s concerns.”
Even at the time these replies hinted at a naïve belief that these measures would suffice to allay fears in the area about the project. There is a difference between scientists providing assurances that the police will behave and the police actually behaving, especially if the experience of the locals diverges from what members of the INO collaboration believe is the case. Members of the collaboration had promised the locals they wouldn’t lose access to grazing land; four years later, the locals still had trouble taking their word. According to an investigation I published at The Wire in 2016, there was also to be a road that bypassed the local villages and led straight to the project site, sparing villagers the noise from the trucks ferrying construction material. It was never built.
One narrative arising from within the scientific community as the project neared the start of construction was that the INO is good for the country, that it will improve our scientific literacy, keep bright minds from leaving to work on similar projects abroad, and help Indians win prestigious prizes. For the national scientific enterprise itself, the INO would make India a site of experimental physics of global importance and Indian scientists working on it major contributors to the study of neutrino physics. I wrote an article to this effect in The Hindu in 2016 and this is also what Takaaki Kajita said in Nandita’s article. But later that year, I also asked an environmental activist (and a mentor of sorts) what he was thinking. He said the scientists will eventually get what they want but that they, the activists et al., still had to do the responsible thing and protest what they perceived to be missteps. (Most scientists in India don’t get what they want but many do, most recently like the ‘Challakere Science City’.)
Curiously, both these narratives — the activist’s pessimism and the scientists’ naïvety — could have emerged from a common belief: that the INO was preordained, that its construction was fated to be successful, causing one faction to be fastidious and the other to become complacent. Of course it’s too simplistic to be able to explain everything that went wrong, yet it’s also of a piece with the fact that the INO was doomed as much by circumstance as by historical baggage. That work on the INO was stalled by an opposition campaign that included fear-mongering pseudoscience and misinformation is disagreeable. But we also need to ask whether some actors resorted to these courses of action because others had been denied them, in the past if not in the immediate present — or potentially risk the prospects of a different science experiment in future.
Physics is often far removed from the precepts of behavioural science and social justice but public healthcare is closer. There is an important parallel between the scientists’ attempts to garner public support for the project and ASHA workers’ efforts during the COVID-19 pandemic to vaccinate people in remote rural areas. These latter people were distrustful of the public healthcare system: it had neglected them for several years but then it was suddenly on their doorstep, expecting them to take a supposedly miraculous drug that would cut their chances of dying of the viral disease. ASHA workers changed these people’s minds by visiting them again and again, going door to door, and enrolling members of the same community to convince people they were safe. Their efficacy is higher if they are from the same community themselves because they can strike up conversations with people that draw on shared experiences. Compare this with the INO collaboration’s belief that a press release from the DAE had changed people’s minds about the project.
Today the INO stares at a bleak future rendered more uncertain by a near-complete lack of political support.
This post benefited from Thomas Manuel’s feedback.
What came first: physics or the world? It’s obviously the world, whereas physics (as a branch of science) offered ways to acquire information about the world and organise it. To not understand something in this paradigm, then, is to not understand the world in terms of physics. While this is straightforward, some narratives lead to confusion.
For example, consider the statement “animals use physics” (these animals exclude humans). Do they? Fundamentally, animals can’t use physics because their brains aren’t equipped to. They also don’t use physics because they’re only navigating the world, they’re not navigating physics and its impositions on the human perception of the world.
On July 10, Knowablepublished an article describing just such a scenario. The article actually uses both narratives — of humans using physics and animals using physics — and they’re often hard to pry apart, but sometimes the latter makes its presence felt. Example:
“Evolution has provided animals with movement skills adapted to the existing environment without any need for an instruction manual. But altering the environment to an animal’s benefit requires more sophisticated physics savvy. From ants and wasps to badgers and beavers, various animals have learned how to construct nests, shelters and other structures for protection from environmental threats.”
An illustration follows of a prairie dog burrow that accelerates the flow of wind and enhance ventilation; its caption reads: “Prairie dogs dig burrows with multiple entrances at different elevations, an architecture that relies on the laws of physics to create airflow through the chamber and provide proper ventilation.”
Their architecture doesn’t rely on the laws of physics. It’s that we’ve physics-fied the prairie dogs’ empirical senses and lessons they learnt in their communities to see physics in the world when in fact it’s not there. Instead, what’s there is evidence of the prairie dogs ability to build these tunnels and exploit certain facts of nature, knowledge of which they’re acquired with experience.
The rest of the article is actually pretty good, exploring animal behaviour that “depends in some way on the restrictions imposed, and opportunities permitted, by physics”. Also, what’s the harm, you ask, in saying “animals use physics”? I’ve no idea. But rather than as they could be, I think it should matter to describe things as they are.
Researchers from the University of Delaware have developed a chemical reaction that can break polyester in clothing down to a simpler compound that can be used to make more clothes. The reaction also spares cotton and nylon, allowing them to be recovered separately from clothing that uses a mix of fibres. Most of all, given sufficient resources, the reaction reportedly takes only 15 minutes from start to finish, which the researchers have touted as a significant achievement because I believe the prevailing duration for other chemical material-recovery processes in the textile industry is in the order of days, and have said they hope to be able to bring it down to a matter of seconds.
The team’s paper and its coverage in the popular press also advance the narrative that the finding could be a boon for the textile industry’s monumental waste problem, especially in economically developing and developed regions. This is obviously the textile industry’s analogue of carbon capture and storage (CCS) technologies, whereby certain technical machinations remove carbon out of the atmosphere and other natural reservoirs and sequester it in human-made matrices for decades or even centuries. The problem with CCS is also the problem with the chemical recycling process described in the new study: unless the state institutes policies and helps effect cultural changes in parallel that discourage consumption, encourage reuse, and lower emissions, removing contaminants from the environment will only create the impression that there is now more room to pollute, so the total effective carbon pollution will increase. This is not unlike trying to reduce motor vehicle traffic by building more roads: cities simply acquire more vehicles with which to fill the newly available motorway space.
All this said, however, there is one more thing to be concerned about vis-à-vis the 15-minute chemical recovery technique. In their paper, the researchers described a “techno-economic assessment” they undertook to understand the “economic feasibility” of their proposed solution to the textile waste problem. Their analysis flowchart is shown below, based on a “textile feed throughput of 500 kg/hour”. A separate table (available here) specifies the estimated market value of textile components — polyester, nylon, cotton, and 4,4′-methylenedianiline (MDA) — after they have been recovered from the 15-minute reaction’s output and processed a bit. They found their process is more economically feasible, achieving a profitability index of 1.29 where 1 is the breakeven point, when the resulting product sales amount to $148.7 million. I don’t know where the latter figure comes from; if it doesn’t have a sound basis and is arbitrary, the ‘1.29’ figure would be arbitrary too. The same goes for their ‘low sales’ scenario in which the profitability index is 0.95 if sales amount to $85.3 million.
Source: DOI: 10.1126/sciadv.ado6827
Importantly, all these numbers presume demand for recycled clothes, which I assume is far more limited (based on my experiences in India) than the demand for new clothes. In fact the researchers’ paper begins by blaming fast fashion for the “rising demand for textiles and [their] shorter life span compared to a generation ago”. Fast fashion is a volume business predicated among other things on lower costs. (Did you hear about the mountain of clothes that went up in flames in the middle of the Atacama desert in 2022 because it was cheaper to let them go that way?) Should fast-fashion’s practices be accounted for in the techno-economic assessment, I doubt its numbers would still stand. They certainly won’t if implemented in the poorer countries to which richer ones have been exporting both textile manufacturing and disposal. Second, the profitability indices presume continuing, if not increasing, demand for new clothes, which is of course deeply problematic: demand untethered from their socio-economic consequences is what landed us in the present soup. That it should stay this way or further increase in order to sustain a process that “holds the potential to achieve a global textile circularity rate of 88%” is a precarious proposition because it risks erecting demand as the raison d’être of sustainability.
Finally, militating against solutions like CCS and this chemical recovery technique because they aren’t going to be implemented within the right policy and socio-cultural frameworks is reasonable even if the underlying technologies have matured completely (they haven’t in this case but let’s set that aside). On the flip side, we need to push governments to design and implement the frameworks asap rather than delay or deny the use of these technologies altogether. The pressures of climate change have shortened deadlines and incentivised speed. Yet business people and industrialists have imported far too many such solutions into India, where their purported benefits have seldom come to fruition — especially in their intended form — even as they have had toxic consequences for the people depending on these industries for their livelihoods, for the people living around these facilities, and, importantly, for people involved in parts of the value chain that come into view only when we account for externalised costs. A few illustrative examples are sewage treatment plants, nuclear reactors, hazardous waste management, and various ore-refining techniques.
In all, making the climate transition at the expense of climate justice is a fundamentally stupid strategy.
Featured image: People sort through hundreds of tonnes of clothing in an abandoned factory in Phnom Penh, November 22, 2020. Credit: Francois Le Nguyen/Unsplash.
You need three things to build a clock: an energy source, a resonator, and a counter. In an analog wrist watch, for example, a small battery is the energy source that sends a small electric signal to a quartz crystal, which, in response, oscillates at a specific frequency (piezoelectric effect). If the amount of energy in each signal is enough to cause the crystal to oscillate at its resonant frequency, the crystal becomes the resonator. The counter tracks the crystal’s oscillation and converts it to seconds using predetermined rules.
Notice how the clock’s proper function depends on the relationship between the battery and the quartz crystal and the crystal’s response. The signals from the battery have to have the right amount of energy to excite the crystal to its resonant frequency and the crystal’s oscillation in response has to happen at a fixed frequency as long as it receives those signals. To make better clocks, physicists have been able to fine-tune these two parameters to an extreme degree.
Today, as a result, we have clocks that don’t lose more than one second of time every 30 billion years. These are the optical atomic clocks: the energy source is a laser, the resonator is an atom, and the counter is a particle detector.
An atomic clock’s identity depends on its resonator. For example, many of the world’s countries use caesium atomic clocks to define their respective national “frequency standards”. (One such clock at the National Physical Laboratory in New Delhi maintains Indian Standard Time.) A laser imparts a precise amount of energy to excite a caesium-133 atom to a particular higher energy state. The atom soon after drops from this state to its lower ground state by emitting light of frequency exactly 9,192,631,770 Hz. When a particle detector receives this light and counts out 9,192,631,770 waves, it will report one second has passed.
Caesium atomic clocks are highly stable, losing no more than a second in 20 million years. In fact, scientists used to define a second in terms of the time Earth took to orbit the Sun once; they switched to the caesium atomic clock because “it was more stable than Earth’s orbit” (source).
But there is also room for improvement. The higher the frequency of the emitted radiation, the more stable an atomic clock will be. The emission of a caesium atomic clock has a frequency of 9.19 GHz whereas that in a strontium clock is 429.22 THz and in a ytterbium-ion clock is 642.12 THz — in both cases five orders of magnitude higher. (9.19 GHz is in the microwave frequency range whereas the other two are in the optical range, thus the name “optical” atomic clock.)
Optical atomic clocks also have a narrower linewidth, which is the range of frequencies that can prompt the atom to jump to the higher energy level: the narrower the linewidth, the more precisely the jump can be orchestrated. So physicists today are trying to build and perfect the next generation of atomic clocks with these resonators. Some researchers have said they could replace the caesium frequency standard later this decade.
But yet other physicists have also already developed an idea to build the subsequent generation of clocks, which are expected to be at least 10-times more accurate than optical atomic clocks. Enter: the nuclear clock.
When an atom, like that of caesium, jumps between two energy states, the particles gaining and losing the energy are the atom’s electrons. These electrons are arranged in energy shells surrounding the nucleus and interact with the external environment. For a September 2020 article in The Wire Science, IISER Pune associate professor and a member of a team building India’s first strontium atomic clock Umakant Rapol said the resonator needs to be “immune to stray magnetic fields, electric fields, the temperature of the background, etc.” Optical atomic clocks achieve this by, say, isolating the resonator atoms within oscillating electric fields. A nuclear clock offers to get rid of this problem by using an atom’s nucleus as the resonator instead.
Unlike electrons, the nucleus of an atom is safely ensconced further in, where it is also quite small, making up only around 0.01% of the atom’s volume. The trick here is to find an atomic nucleus that’s stable and whose resonant frequency is accessible with a laser.
In 1976, physicists studying the decay of uranium-233 nuclei reported some properties of the thorium-229 nucleus, including estimating that the lowest higher-energy level to which it could jump required less than 100 eV of energy. Another study in 1990 estimated the requirement to be under 10 eV. In 1994, two physicists estimated it to be around 3.5 eV. The higher energy state of a nucleus is called its isomer and is denoted with the suffix ‘m’. For example, the isomer of the thorium-229 nucleus is denoted thorium-229m.
After a 2005 study further refined the energy requirement to 5.5 eV, a 2007 study provided a major breakthrough. With help from state-of-the-art instruments at NASA, researchers in the US worked out the thorium-229 to thorium-229m jump required 7.6 eV. This was significant. Energy is related to frequency by the Planck equation: E = hf, where h is Planck’s constant. To deliver 3.5 eV of energy, then, a laser would have to operate in the optical or near-ultraviolet range. But if the demand was 7.6 eV, the laser would have to operate in the vacuum ultraviolet range.
Further refinement by more researchers followed but they were limited by one issue: since they still didn’t have a sufficiently precise value of the isomeric energy, they couldn’t use lasers to excite the thorium-229 nucleus and find out. Instead, they examined thorium-229m nuclei formed by the decay of other elements. So when on April 29 this year a team of researchers from Germany and Austria finally reported using a laser to excite thorium-229 nuclei to the thorium-229m state, their findings sent frissons of excitement through the community of clock-makers.
The researchers’ setup had two parts. In the first, they drew inspiration from an idea a different group had proposed in 2010: to study thorium-229 by placing these atoms inside a larger crystal. The European group grew two calcium fluoride (CaF2) crystals in the lab doped heavily with thorium-229 atoms, with different doping concentrations. In a study published a year earlier, different researchers had reported observing for the first time thorium-229m decaying back to its ground state while within calcium fluoride and magnesium fluoride (MgF2) crystals. Ahead of the test, the European team cooled the crystals to under -93º C in a vacuum.
In the second part, the researchers built a laser with output in the vacuum ultraviolet range, corresponding to a wavelength of around 148 nm, for which off-the-shelf options don’t exist at the moment. They achieved the output instead by remixing the outputs of multiple lasers.
The researchers conducted 20 experiments: in each one, they increased the laser’s wavelength from 148.2 nm to 150.3 nm in 50 equally spaced steps. They also maintained a control crystal doped with thorium-232 atoms. Based on these attempts, they reported their laser elicited a distinct emission from the two test crystals when the laser’s wavelength was 148.3821 nm. The same wavelength when aimed at the CaF2 crystal doped with thorium-232 didn’t elicit an emission. This in turn implied an isomeric transition energy requirement of 8.35574 eV. The researchers also worked out based on these details that a thorium-229m nucleus would have a half-life of around 29 minutes in vacuum — meaning it is quite stable.
Physicists finally had their long-sought prize: the information required to build a nuclear clock by taking advantage of the thorium-229m isomer. In this setup, then, the energy source could be a laser of wavelength 148.3821 nm; the resonator could be thorium-229 atoms; and the counter could look out for emissions of frequency 2,020 THz (plugging 8.355 eV into the Planck equation).
Other researchers have already started building on this work as part of the necessary refinement process and have generated useful insights as well. For example, on July 2, University of California, Los Angeles, researchers reported the results of a similar experiment using lithium strontium hexafluoroaluminate (LiSrAlF6) crystals, including a more precise estimate of the isomeric energy gap: 8.355733 eV.
About a week earlier, on June 26, a team from Austria, Germany, and the US reported using a frequency comb to link the frequency of emissions from thorium-229 nuclei to that from a strontium resonator in an optical atomic clock at the University of Colorado. A frequency comb is a laser whose output is in multiple, evenly spaced frequencies. It works like a gear that translates the higher frequency output of a laser to a lower frequency, just like the lasers in a nuclear and an optical atomic clock. Linking the clocks up in this way allows physicists to understand properties of the thorium clock in terms of the better-understood properties of the strontium clock.
Atomic clocks moving into the era of nuclear resonators isn’t just one more step up on the Himalayan mountain of precision timekeeping. Because nuclear clocks depend on how well we’re able to exploit the properties of atomic nuclei, they also create a powerful incentive and valuable opportunities to probe nuclear properties.
In a 2006 paper, a physicist named VV Flambaum suggested that if the values of the fine structure constant and/or the strong interaction parameter change even a little, their effects on the thorium-229 isomeric transition would be very pronounced. The fine structure constant is a fundamental constant that specifies the strength of the electromagnetic force between charged particles. The strong interaction parameter specifies this vis-à-vis the strong nuclear force, the strongest force in nature and the thing that holds protons and neutrons together in a nucleus.
Probing the ‘stability’ of these numbers in this way opens the door to new kinds of experiments to answer open questions in particle physics — helped along by physicists’ pursuit of a new nuclear frequency standard.
Featured image: A view of an ytterbium atomic clock at the US NIST, October 16, 2014. Credit: N. Phillips/NIST.
A 2022 trip to Dubai made me wonder how much research there was on the effects cities, especially those that are rapidly urbanising as well as are building taller, wider structures more closely packed together, had on the winds that passed through them. I found only a few studies then. One said the world’s average wind speed had been increasing since 2010, but its analysis was concerned with the output of wind turbines, not the consequences within urban settlements. Another had considered reducing wind speed within cities as a result of the Venturi effect by planting more trees. I also found a The New York Times article from 1983 about taller skyscrapers directing high winds downwards, to the streets. That was largely it. Maybe I didn’t look hard enough.
On June 11, researchers in China published a paper in the Journal of Advances in Modelling Earth Systems in which they reported findings based on a wind speed model they’d built for Shanghai city. According to the paper, Shanghai’s built-up area could slow wind speed by as much as 50%. However, they added, the urban heat-island effect could enhance “the turbulent exchange in the vertical direction of the urban area, and the upper atmospheric momentum is transported down to the surface, increasing the urban surface wind speed”. If the heat-island effect was sufficiently pronounced, then, the wind may not slow at all. I imagine the finding will be useful for people considering the ability of winds to transport pollutants to and disperse them in different areas. I’m also interested in what the model shows for Delhi (which can be hotter), Mumbai (wetter), and Chennai (fewer tall buildings). The relationship between heat-islands and the wind energy is also curious because city parts that are windier are also less warm.
But overall, even if the population density within skyscrapers may be lower than in non-skycraping buildings and tenements, allowing them to built closer together, as is normal in cities like Dubai, where these buildings are almost all located in a “business district” or a “financial district”, could also make it harder for the wind to ventilate these spaces.
I wrote the lead article, about why scientists are so interested in an elementary particle called the top quark. Long story short: the top quark is the heaviest elementary particle, and because all elementary particles get their masses by interacting with Higgs bosons, the top quark’s interaction is the strongest. This has piqued physicists’ interest because the Higgs boson’s own mass is peculiar: it’s more than expected and at the same time poised on the brink of a threshold beyond which our universe as we know it wouldn’t exist. To explain this brinkmanship, physicists are intently studying the top quark, including measuring its mass with more and more precision.
It’s all so fascinating. But I’m well aware that not many people are interested in this stuff. I wish they were and my reasons follow.
There exists a sufficiently healthy journalism of particle physics today. Most of it happens in Europe and the US, (i) where famous particle physics experiments are located, (ii) where there already exists an industry of good-quality science journalism, and (iii) where there are countries and/or governments that actually have the human resources, funds, and political will to fund the experiments (in many other places, including India, these resources don’t exist, rendering the matter of people contending with these experiments moot).
In this post, I’m using particle physics as itself as well as as a surrogate for other reputedly esoteric fields of study.
This journalism can be divided into three broad types: those with people, those concerned with spin-offs, and those without people. ‘Those with people’ refers to narratives about the theoretical and experimental physicists, engineers, allied staff, and administrators who support work on particle physics, their needs, challenges, and aspirations.
The meaning of ‘those concerned with spin-offs’ is obvious: these articles attempt to justify the money governments spend on particle physics projects by appealing to the technologies scientists develop in the course of particle-physics work. I’ve always found these to be apologist narratives erecting a bad expectation: that we shouldn’t undertake these projects if they don’t also produce valuable spin-off technologies. I suspect most particle physics experiments don’t because they are much smaller than the behemoth Large Hadron Collider and its ilk, which require more innovation across diverse fields.
‘Those without people’ are the rarest of the lot — narratives that focus on some finding or discussion in the particle physics community that is relatively unconcerned with the human experience of the natural universe (setting aside the philosophical point that the non-human details are being recounted by human narrators). These stories are about the material constituents of reality as we know it.
When I say I wish more people were interested in particle physics today, I wish they were interested in all these narratives, yet more so in narratives that aren’t centred on people.
Now, why should they be concerned? This is a difficult question to answer.
I’m concerned because I’m fascinated with the things around us we don’t fully understand but are trying to. It’s a way of exploring the unknown, of going on an adventure. There are many, many things in this world that people can be curious about. It’s possible there are more such things than there are people (again, setting aside the philosophical bases of these claims). But particle physics and some other areas — united by the extent to which they are written off as being esoteric — suffer from more than not having their fair share of patrons in the general (non-academic) population. Many people actively shun them, lose focus when reading about them, and at the same time do little to muster focus back. It has even become okay for them to say they understood nothing of some (well-articulated) article and not expect to have their statement judged adversely.
I understand why narratives with people in them are easier to understand, to connect with, but none of the implicated psychological, biological, and anthropological mechanisms also encourage us to reject narratives and experiences without people. In other words, there may have been evolutionary advantages to finding out about other people but there have been no disadvantages attached to engaging with stories that aren’t about other people.
Next, I have met more than my fair share of people that flinched away from the suggestion of mathematics or physics, even when someone offered to guide them through understanding these topics. I’m also aware researchers have documented this tendency and are attempting to distil insights that could help improve the teaching and the communication of these subjects. Personally I don’t know how to deal with these people because I don’t know the shape of the barrier in their minds I need to surmount. I may be trying to vault over a high wall by simplifying a concept to its barest features when in fact the barrier is a low-walled labyrinth.
Third and last, let me do unto this post what I’m asking of people everywhere, and look past the people: why should we be interested in particle physics? It has nothing to offer for our day-to-day experiences. Its findings can seem totally self-absorbed, supporting researchers and their careers, helping them win famous but otherwise generally unattainable awards, and sustaining discoveries into which political leaders and government officials occasionally dip their beaks to claim labels like “scientific superpower”. But the mistake here is not the existence of particle physics itself so much as the people-centric lens through which we insist it must be seen. It’s not that we should be interested in particle physics; it’s that we can.
Particle physics exists because some people are interested in it. If you are unhappy that our government spends too much on it, let’s talk about our national R&D expenditure priorities and what the practice, and practitioners, of particle physics can do to support other research pursuits and give back to various constituencies. The pursuit of one’s interests can’t be the problem (within reasonable limits, of course).
More importantly, being interested in particle physics and in fact many other branches of science shouldn’t have to be justified at every turn for three reasons: reality isn’t restricted to people, people are shaped by their realities, and our destiny as humans. On the first two counts: when we choose to restrict ourselves to our lives and our welfare, we also choose to never learn about what, say, gravitational waves, dark matter, and nucleosynthesis are (unless these terms turn up in an exam we need to pass). Yet all these things played a part in bringing about the existence of Earth and its suitability for particular forms of life, and among people particular ways of life.
The rocks and metals that gave rise to waves of human civilisation were created in the bellies of stars. We needed to know our own star as well as we do — which still isn’t much — to help build machines that can use its energy to supply electric power. Countries and cultures that support the education and employment of people who made it a point to learn the underlying science thus come out on top. Knowing different things is a way to future-proof ourselves.
Further, climate change is evidence humans are a planetary species, and soon it will be interplanetary. Our own migrations will force us to understand, eventually intuitively, the peculiarities of gravity, the vagaries of space, and (what is today called) mathematical physics. But even before such compulsions arise, it remains what we know is what we needn’t be afraid of, or at least know how to be afraid of. 😀
Just as well, learning, knowing, and understanding the physical universe is the foundation we need to imagine (or reimagine) futures better than the ones ordained for us by our myopic leaders. In this context, I recommend Shreya Dasgupta’s ‘Imagined Tomorrow’ podcast series, where she considers hypothetical future Indias in which medicines are tailor-made for individuals, where antibiotics don’t exist because they’re not required, where clean air is only available to breathe inside city-sized domes, and where courtrooms use AI — and the paths we can take to get there.
Similarly, with particle physics in mind, we could also consider cheap access to quantum computers, lasers that remove infections from flesh and tumours from tissue in a jiffy, and communications satellites that reduce bandwidth costs so much that we can take virtual education, telemedicine, and remote surgeries for granted. I’m not talking about these technologies as spin-offs, to be clear; I mean technologies born of our knowledge of particle (and other) physics.
At the biggest scale, of course, understanding the way nature works is how we can understand the ways in which the universe’s physical reality can or can’t affect us, in turn leading the way to understanding ourselves better and helping us shape more meaningful aspirations for our species. The more well-informed any decision is, the more rational it will be. Granted, the rationality of most of our decisions is currently only tenuously informed by particle physics, but consider if the inverse could be true: what decisions are we not making as well as we could if we cast our epistemic nets wider, including physics, biology, mathematics, etc.?
Consider, even beyond all this, the awe astronauts who have gone to Earth orbit and beyond have reported experiencing when they first saw our planet from space, and the immeasurable loneliness surrounding it. There are problems with pronouncements that we should be united in all our efforts on Earth because, from space, we are all we have (especially when the country to which most of these astronauts belong condones a genocide). Fortunately, that awe is not the preserve of spacefaring astronauts. The moment we understood the laws of physics and the elementary constituents of our universe, we (at least the atheists among us) may have realised there is no centre of the universe. In fact, there is everything except a centre. How grateful I am for that. For added measure, awe is also good for the mind.
It might seem like a terrible cliché to quote Oscar Wilde here — “We are all in the gutter, but some of us are looking at the stars” — but it’s a cliché precisely because we have often wanted to be able to dream, to have the simple act of such dreaming contain all the profundity we know we squander when we live petty, uncurious lives. Then again, space is not simply an escape from the traps of human foibles. Explorations of the great unknown that includes the cosmos, the subatomic realm, quantum phenomena, dark energy, and so on are part of our destiny because they are the least like us. They show us what else is out there, and thus what else is possible.
If you’re not interested in particle physics, that’s fine. But remember that you can be.
Featured image: An example of simulated data as might be observed at a particle detector on the Large Hadron Collider. Here, following a collision of two protons, a Higgs boson is produced that decays into two jets of hadrons and two electrons. The lines represent the possible paths of particles produced by the proton-proton collision in the detector while the energy these particles deposit is shown in blue. Caption and credit: Lucas Taylor/CERN, CC BY-SA 3.0.
