To understand #NotInMyName

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Shivam Vij published this on June 27. Excerpt:

[Liberals] still romanticise their days at the JNU campus in the ’80s – what an innocent time it was. The still think their marches and slogans will Bring Down Fascism. The people who will march today, feeling self-important about fighting the good fight, don’t understand they are actually helping Hindutva. The more you make a campaign out of Hindutva obsessions – cows, meat, Muslims – these keywords become the central agenda of politics.

Liberals think they can take on Hindutva on its turf and defeat it. That this is not possible should be obvious after the experience since Babri. The only way Hindutva could be defeated is to change the keywords of political discourse from the ones Hindutva wants – cows, meat, Muslims – to the ones it is more apologetic about, such as violence against Dalits, farmers’ agitations, the distress faced by small traders due to demonetisation and GST.

Ashley Tellis rebutted with this on June 28. Excerpt:

[Vij] contradicts himself right off the bat by pointing to the rise of attacks on Muslims since the BJP came to power and then spends the rest of the article telling us that we should not use the word Muslim at all as that is rising to the click-baiting of the BJP. He teaches us that we must give up the words ‘cows, meat and Muslims’ and replace them with ‘Dalit, farmer, small trader.’ It is the stupidest piece of advice ever given by a journalist to anyone. But then, journalists like Vij tend to be the stupidest people around. So perhaps he should take this advice himself and not write articles about protests that according to him have nothing to do with Dalits, farmers and small traders.

I’m coming into this issue as someone who’s not ignorant as much as has embarrassing trouble understanding the syntax and language of such issues. Earlier yesterday, I’d had my doubts about #NotInMyName and asked a friend about them. At first he seemed dismissive (calling my concerns “wooly”) but after some badgering, he answered them one by one (I had nine questions). By not attacking my observations and explaining to me where I was wrong, he has gained an ally (irrespective of how much that means to him or his causes). But how Tellis has replied to Vij I think will make it harder for anyone who is simply looking for answers to take a stronger position in public debates, and to approach him with their doubts.

I realise that Tellis is fully within his rights to call Vij ‘stupid’, as well as that the fight against Hindutva fascists is as sensitive as it is crucial and in which no one will spare anyone else any inches (either in newspaper columns or political estate). I also realise that Vij is an experienced journalist and whose views should have been debated as such (instead of by disparaging all journalistic commentary). For example, by discussing why he sees it fit to make an overly specialised point about strategies when #NotInMyName is really about concerned citizens speaking out against a particularly insidious motivation for murder, as well as the murders themselves, as a collective for the first time. However, a very important intra-communal unity is at stake here: the more vicious public debates we have, the more it will seem like a ‘conversation’ cordoned off to those masses for whom an awareness of social and political issues is only just budding. It places quite the cost on being uninformed (not being ignorant) that those who would like to be informed might not deserve (and it can’t be that everyone’s undeserving of it!). And when this cost is already so high, when the specialised language of the social sciences is already so hard to decipher for an outsider, Tellis’s – and Vij’s and others’ – level of incivility only makes things worse. This isn’t to say Vij wasn’t saying disagreeable things – but only that there’s a way to dismiss them, and how Tellis did it seemed less that and more… spectacle.

As my friend Akhil told me, “To me, the tone and argument of Shivam Vij’s article seems more problematic than Tellis’s response. Of course Tellis could have countered it better than firing off a rant, but who encourages Tellis’s style of writing and who benefits from it explains why such messy debates exist and there’s little we can do about it. Vij wrote a piece lacking substance, but controversial enough to generate traffic, saying things just for the sake of saying things. I’m not sure he wanted a meaningful debate in the first place.And I’m sure Tellis didn’t want a scholarly debate at all because he found the very premise of the arguments ridiculous.” All this also prompts the consideration: Tellis v. Vij, and Tellis v. Rajamani (salvo, return), both played out on the pages of journalism websites (Huffington Post, News Minute and Sify). Should these websites, or any others for that matter, have also been responsible for first introducing the issue (not just as a staid news report like Business Standard did but also in the form of a very important debate playing out between scholars – Vij may not have been one but Rajesh Rajamani  and Tellis both are), through which readers could be appraised not just of the overarching narrative of fascists v. liberals but also that of how scholars are choosing to frame – or not frame – their relationship with #NotInMyName? I think so.

More Akhil: “Either we can enjoy lengthy theoretical debates on the internet or physically make our presence felt. A healthy cultural of debate is always desirable, but when the intent is malicious and counterproductive to actual efforts to make things better in such desperate times, it’s difficult to hold back angst in the interest of civility. The onus is of course on the editors of the websites to present the debate in such a manner that serves a more important purpose (to give the audience diverse perspectives) rather than to run clickbait rant that eventually leaves little space for critical engagement.”

My friend’s answers, in case anyone’s interested:

1. Who is the campaign for? Whose attention will the attendees be clamouring for?

For the bulk of Indians (or Hindus, more precisely), whose silence in the face of the BJP’s majoritarianism is providing space for the lynchers and killers.

2. How will (anyone) participating in #NotInMyName help the oppressed minorities?

Oppressed minorities will feel hugely relieved and reassured by a good turnout across the country. I would say the overall size is what will reassure them more than individual names or faces.

3. Doesn’t the name ‘#NotInMyName’ feel more like an abdication than a protest?

The crimes are being committed in the name of ‘nation’, ‘Hinduism’, ‘Bharat mata’, ‘Indian values’, etc., so it is important for people to say, “Sorry, you don’t have exclusive rights to define what is Indian, what is Hindu, what are Hindu values, etc.”

4. Saba Dewan, the filmmaker whose Facebook post snowballed into the #NotInMyName protests, told Business Standard, “We want to convey that whatever is happening in the society is not happening in our name; I do not approve of it.” Why do we presume those who are perpetrating the lynchings care what the urban, upper-class, upper-caste observers think?

Those who are perpetrating may not care but the puppet masters who have created a culture of impunity, who control the police and whose own statements have encouraged the lynch mentality, DO CARE – especially about what the urban, upper-class-upper-caste thinks.

5. Are the campaign’s organisers making any efforts to actively involve minorities in a meaningful way? And is there a way to do this without turning it into a spectacle?

I think the idea is really to ensure Hindus turn out in the largest possible numbers. I suspect people are sending the call to Muslim friends as a kind of solidarity message but to Hindu friends in order to ensure they turn up.

6. The protests are set to be held in 11 cities: New Delhi, Mumbai, Kolkata, Hyderabad, Bangalore, Trivandrum, Kochi, Patna, Lucknow, London, Toronto. According to an IndiaSpend analysis, cows-related violence since 2014 hasn’t happened in any of these cities but in usually rural areas outside them.

This is a solidarity event so it doesn’t matter where cow-related violence took place.

7. What does the ‘name’ in #NotInMyName stand for? If it denotes religious orders and/or caste, then why does it appear to be an exclusively upper-caste mobilisation?

The Indian upper middle class is largely upper caste so it may appear that this is an upper caste mobilisation, in the same way rallies for LGBTQIA+, FoE, media freedom, etc. issues do.

8. Isn’t there a difference between Muslims using the phrase ‘Not In My Name’ to speak out against ISIS’s brand of Islam, or Americans using it to speak out against their government using their money to fund the War Against Terrorism, and privileged people marching under the banner to decry lynchings perpetrated in the name of preserving the same socio-religious order whose benefits they enjoy?

All of these cases are different. The anti-ISIS protests come from genuine Muslim revulsion against ISIS but also the pressure in Western society for the participants to dissociate from Islamic extremism.

Americans against War on Terror is similar to the Indian protest today, where people in whose name bad things are done (war on terror, attacks on minorities) tell the rulers to STFU. Sure, the rulers can say, “You STFU, you are enjoying the privileges of being American (cheap oil, etc.)” – or Hindu – but that is neither here nor there as an argument.

9. To the people saying “not in my name”: what do you usually lend your name to?

The answer is obvious: just look at the petitions we have carried on The Wire over the past two years by pretty much the same set of folks doing today’s mobilisation: justice for Rohith Vemula, Akhlaq, Pehlu Khan, support of FoE, etc. etc.

Featured image credit: OpenClipart-Vectors/pixabay.

Communication, journalism and bullshit

A week or two ago, a scientist impressed with The Wire‘s coverage of science recommended that I stick to covering the good stuff (my syntax) and keep away from highlighting pseudoscience and other happenings of questionable footing.

Then, a few days ago, a science writer expressed an adjacent set of complaints to me. He said that (a) he had a problem with most science journalism simply being science communication, and (b) that whatever was being communicated was invariably optimistic about science’s intention itself.

Both these men are expressing valid concerns – but my disagreement with them was almost immediate. And the reason I’m discussing them here is that the scientist’s advice and the writer’s first complaint allude to a common concern: do people know how to differentiate between science and pseudoscience?

It’s a skill many of us take for granted, often because we’re aware of

  1. The investigative methods of science
  2. Common sources of inaccuracy and imprecision, and
  3. The features of scientific publishing

– all topped off with a passing familiarity with subjects most often in the news. For example, almost everyone in my social circles will suspect a news article claiming scientists have successfully cloned a fully grown human being or resurrected a mammoth. But I can’t say that all my readers will be able to as well.

So covering pseudoscience and research misconduct is a way to, first, highlight the existence of these modes of interrogating a claim and, second, to encourage readers to employ them with every (scientific) claim they’re ever faced with.

Another way to elucidate these modes – and delineate more like them – is to communicate sound science (as distinct from addressing it as a journalist). A typical example of this is for the communicator to take up a seemingly complicated piece of science and break it down in such a way that you stay faithful to scientists and their work – as well as to your intention to ensure a non-scientist gets the science and its spirit.

To “let the science speak for itself” – as the scientist told me – first requires an awareness of the boundaries within which scientific claims must qualify themselves. In a country like India, I suspect (from experience) that many people are unaware of these boundaries. It might not even be far-fetched to say that, in these circumstances, science communication is a form of science journalism. And science journalism can only benefit from a readership that knows and asks the right questions.

I’m reminded at this point of the words of Eric Hobsbawm (The Age of Extremes, p. 530):

The suspicion and fear of science [in the early to mid-nineteenth century] was fuelled by four feelings: that science was incomprehensible; that both its practical and moral consequences were unpredictable and probably catastrophic; and that it underlined the helplessness of the individual, and undermined authority. Nor should we overlook the sentiment that, to the extent that science interfered with the natural order of things, it was inherently dangerous.

Science can have these attributes (at times more so than we might like to acknowledge) and such effects, and that’s when science journalism – a la the writer’s second concern – is required. But it has to be preceded by science communication, or Gwyneth Paltrow is going to sell you her jade dildos. Or worse.

Featured image credit: Hans/pixabay.

Why Wonder Woman's breastplate isn't disappointing

The Wonder Woman armour piece of June 19 is already among the most-read pieces on this blog that were published in the last year, and quite a few people have stepped forward to give me their take on Twitter and over email. Thanks for all the responses – it’s been an unexpectedly wonderful learning experience. 🙂 This said, one of those who replied, my friend Ishita Roy, also told me why – the logic in my piece notwithstanding – she isn’t actually disappointed by Wonder Woman’s garb in the film. I’ve reproduced her complete response below (from her Facebook comment). –VM

Your analysis of Wonder Woman armour is technically and logically sound. It should be disappointing to see her in such impractical (dangerous, as you pointed out) and male-gaze oriented “armour”. However, allow me to suggest a few reasons for the lack of disappointment here.

1. The origins: William Marston, who co-created the character with his wife, based her design on bondage (BDSM) gear. This is actually in line with the origin of Superman, whose original artist also was inspired by BDSM.

The idea here was not to cater to the male gaze, but to strike the same chord as the image of a dominatrix.
Indeed, Marston’s credentials and intentions were rather impeccable – he was a psychologist and a feminist, and in a polyamorous relationship with two other queer feminists, both of whom had heavy inputs in the making of Wonder Woman.

2. The “armour” is not actually accompanied by the male gaze.

There is not a single shot in the movie which tracks the bodies of any of the amazons. Not a single shot. The attire of the amazons is treated with superb nonchalance in the movie. Of particular note are two scenes: Diana is catcalled when she first appears in London, hidden under a cloak, and later in her green outfit – both of which would be perceived as modest by most folks. But when she appears in her armour, and starts kicking ass, she not even ogled at.

That’s a huge message to send audiences: that women’s clothing is not meant for consumption by an audience. I think giving them actual armour would have subtracted from that message – that women deserve respect regardless of whatever they wear. That even as warriors, modesty is not a requirement.
The whole amazon attire is thoroughly divorced from the concept of objectification by the cinematography, script and the very suggestive fact that amazons of all ages wear it.

3. That attire may not have been meant as armour.

The fighting style choreographed for the amazons is actively incompatible with plate-mail. It depends on ranged attacks, acrobatics and is more coordinated than single combat. Freedom of movement, along with coverage of vitals seems to be the aim here.

Now note that Diana’s attire is more revealing than the standard issue Amazonian garb. Also note that it has been depicted as a museum piece in-story, and is meant to be more ceremonial than actual armour.
Indeed the prevailing fan theory is that it is completely ceremonial, meant to be an appropriate superhero costume for the (wielder of) god-killers rather than a bulletproof vest.

Finally: re Thor and Bruce. Both guys spend a substantial amount of time with a naked torso and, in Thor’s case, wearing non-armoured clothing. Make of that what you will.

Unscientific breastplates

Before I begin, I’d like to make it clear that I’m not obsessed with comic books, and that what follows is based on information gleaned from googling and trawling through internet forums at 1 am. If I’ve got a detail wrong, please point it out nicely and I’m happy to make the necessary corrections.

Wonder Woman the movie was hailed so widely for being what it was but surprisingly few fixated on the protagonist’s clothing – a noticeable departure from reality, where social media commentators often pick on women’s sartorial sensibilities in various circumstances over anything else that might be contextually relevant. I do realise that what Diana Prince chooses to wear is her choice and none of my business. Then again, what about the fact that she happens to be a character created for popular consumption by a man who modelled her after his idea of women: that they feel happy when they are submissive?

There’s more. The reason I’m going to fixate on her clothing now has to do with mechanical engineering (which I studied for my undergraduate degree). Of all the things Prince wears, her breastplate is particularly interesting.

As the visions of sci-fi and fantasy films have evolved in the last few decades, there has also been a noticeable evolution in the liberties taken with set and costume design. Specifically, they have become less displays of their creators’ being awed by the possibilities of the future as well as to contain their fantasies and artistic overtures – and more humdrum, utilitarian and functional. For example, in a limited sense, filmmakers on average have reduced their attention on the “wow” factor of gadgetry, keeping audiences from getting ‘distracted’ by some outlandish vision of the future. Some of my favourite recent examples of this include Iron Man, Nolan’s Batman and Mad Max: Fury Road. The movies’ script is always such that the “wow” object isn’t introduced in our midst suddenly. Its creation process is exposed to the viewer at every step such that the ultimate effect is for the viewer to be viscerally familiar with the object by the time of its deployment in action – especially with the choices behind its more unique features.

But one area in which filmmakers have broadly seemed reluctant to get functionalist about is the breastplate of female warriors. Or at least they have become functional to the extent that their function is to make female warriors looks sexier instead of afford proper protection. For example, consider the battledress of three characters: one each from Game of Thrones, Man of Steel and Wonder Woman.

Faora from the Superman universe (left) and Brienne of Tarth, from Game of Thrones. Source: YouTube
Faora from the Superman universe (left) and Brienne of Tarth, from Game of Thrones. Source: YouTube

While Faora Hu-Ul and Wonder Woman have breastplates that cup the breasts, Brienne of Tarth wears one that doesn’t. This is important because all of them are warriors and their armours must be able to protect them in a variety of conflict situations. One of them is melee combat, and when the breastplate receives a blow, its duty is to lessen the impact on the torso by absorbing it as well as directing it away from sensitive areas. However, when the breastplate cups over the breasts, striking it on top risks the force becoming directed inwards (especially if the seam is bad), towards the ribs and the sternum. This is what Emily Asher-Perrin wrote about for Tor in May 2013:

Assuming that you are avoiding the blow of a sword, your armor should be designed so that the blade glances off your body, away from your chest. If your armor is breast-shaped, you are in fact increasing the likelihood that a blade blow will slide inward, toward the center of your chest, the very place you are trying to keep safe. But that’s not all! Let’s say you even fall onto your boob-conscious armor. The divet separating each breast will dig into your chest, doing you injury. It might even break your breastbone. With a strong enough blow to the chest, it could fracture your sternum entirely, destroying your heart and lungs, instantly killing you. It is literally a death trap—you are wearing armor that acts as a perpetual spear directed at some of your most vulnerable body parts. It’s just not smart.

This is particularly true of Wonder Woman, whose latest costume appears to feature a metallic lining at the helm with a prow in the middle (the ‘golden eagle’) bending into the centre of her chest as well as sharp tips angling over her breasts. How is this sensible? Imagine what would happen if she fell face-down.

A close-up view of Wonder Woman's breastplate. Source: YouTube
A close-up view of Wonder Woman’s breastplate. Source: YouTube

I suppose you’re wondering how it matters considering it’s Wonder Goddamn Woman, a superhero who can take punches harder than any armour would be able to withstand on her bare skin and not flinch. But the same can be said of Thor, and even Dr Bruce Banner, and it’s not like either of them is walking around wearing an iron maiden or a chastity belt just because he can. In effect, while Batman got full-body armour capable of surviving a Rottweiler attack, Wonder Woman had to make do with gear that wasn’t entirely about ‘her choices’. It actually created new ways to harm her (were it not for her Amazonian outside) because it was trying to preserve other things: her sexiness and her symbols. In a March 2016 interview to Hollywood Reporter, Michael Wilkinson, the costume designer who created Wonder Woman’s armour, said:

We created a costume that looks like metal armor, but of course, in these films the fight scenes are very intense and challenging so I had to come up with a solution that would allow her to move and breathe, but also to have this very iconic, sort of hourglass shape in a modern and interesting way. … Of course there’s all sorts of things she has such as the eagle and WW motif throughout the costume, so I tried to use that WW motif through the belt and the gauntlets and across the breastplate. There’s WW throughout the costume. I think someone tried to count them and they got to 40. (Emphasis added.)

What do either of these things have to do with combat efficiency? Again, for those wondering how any of this matters, let me remind you that my point is only that the sensibilities going into designing male armour and female armour seem to be different.

In reality (i.e. when we’re not dealing with superhuman abilities), the answer to this is not to exclude bust cups from female body armour, which is feasible to do only in the case of women with small breasts – but to create new designs that don’t bring additional vulnerabilities over the baseline (i.e. male armour), to focus on individual fit and to test it well. According to an article published in Tech Beat, a magazine of the US National Law Enforcement and Corrections Technology Centre, in December 2014,

Soft body armors designated as female differ from male and gender-neutral vests in that they can incorporate curved or shaped protective panels to accommodate the female bust. Flat male or gender-neutral models may be suitable for female officers with smaller busts. Depending on design and materials, they may not be suitable for those with larger busts, as the busts push the front armor panel forward, enlarging the underarm gap and therefore lessening the area of coverage between the front and rear panels.

Further, according to the US Office of Justice Programs,

Generally speaking, the difference between male and female models is that for the female body armor, most manufacturers cut and stitch the material to create bust cups. … When a female model is tested, the laboratory is instructed to locate the seam that is created by folding and/or stitching the material to make the bust cup, and to place one of the shots on that seam. This is done to ensure the weakest point of the vest (typically a seam) provides the minimum level of ballistic protection required by the standard. … There are many different types and styles of female vests, and ways of fitting vests to accommodate all of the various sizes and shapes needed for female officers. Some manufacturers have developed methods which ‘mold’ the bust cups into the material, negating the need for cutting and stitching to create a bust cup. Other manufacturers simply alter the outside dimensions of the panel (i.e., enlarging the arm hole openings) to accommodate certain types of builds and body types (commonly referred to as a ‘unisex’ vest).

Overall, it seems to be that there can be no single way to verify the strength and integrity of women’s armour as much as subjecting each unit to a single set of tests. Then again, I wonder if there’s any point bringing all these details to bear on Wonder Woman’s armour: how, for starters, are we going to get the Young’s modulus of Amazonian amazongmetal? I’m not sure the movies (including Batman v. Superman) have a scene where Princess Diana falls face down or takes a punch from Superman. In the off chance that such a scene does come to be, I’m going to be interested in her armour’s backface deformation. From a Police One article published in December 2014,

… in ballistic-resistant armor testing, backface deformation (BFD) is the measurement on the indent in a clay backing material when a bullet that does not penetrate a vest makes an impression on the clay. BFD testing of very small panels of armors, as well as whether the amount of allowed deformation should be different for the breast area, could be areas for study. … “The idea is to use a supplemental test technique to ensure that when rounds impact areas of the female anatomy that they have the same level of protection as existing male armors, but when striking the bust area, we want to make sure that we provide a more biofidelic test method that specifically addresses the unique female anatomy,” Otterson says.

Update: Twitter user @shishiqiushi has pointed out that the proper historical comparison for breastplates would be the Roman cuirass. However, I’m not sure where this fits into my narrative because there is no evidence – whether in art or archaeology – that women wore the cuirass into battle, at least not usually. And when they did, they wore versions designed for men. Perhaps I would be able to say that the thinking going into designing men’s armour had some historical basis. For further reading, try this Gizmodo explainer.

Geometry's near-miss that wasn't

On June 8, Nautilus published a piece by Evelyn Lamb talking about mathematical near-misses. Imagine a mathematician trying to solve a problem using a specific technique and imagine it allows her to get really, really close to a solution – but not the solution itself. That’s a mathematical near-miss, and the technique becomes of particular interest to mathematicians because they can reveal potential connections between seemingly unconnected areas of mathematics. Lamb starts the piece talking about geometry but further down she’s got the simplest example: the Ramanujan constant. It is enumerated as e^{π(163^0.5)} (in English, you’d be reading this as “e to the power pi-times the square-root of 163”). It’s equal to 262,537,412,640,768,743.99999999999925. According to mathematician John Baez (quoted in the same article), this amazing near-miss is thanks to 163 being a so-called Heegner number. “Exponentials related to these numbers are nearly integers,” Lamb writes. Her piece concludes thus:

Near misses live in the murky boundary between idealistic, unyielding mathematics and our indulgent, practical senses. They invert the logic of approximation. Normally the real world is an imperfect shadow of the Platonic realm. The perfection of the underlying mathematics is lost under realizable conditions. But with near misses, the real world is the perfect shadow of an imperfect realm. An approximation is “a not-right estimate of a right answer,” Kaplan says, whereas “a near-miss is an exact representation of an almost-right answer.”

It was an entirely fun article (not just because I’ve a thing for articles discussing science that has no known paractical applications). However, the minute I read the headline (‘The Impossible Mathematics of the Real World’), one other science story from the past – which turned out to be of immense practical relevance – immediately came to mind: that of the birth of non-Euclidean geometry. In 19th century Europe, the German polymath Carl Friedrich Gauss realised that though people regularly approximated the shapes of real-world objects to those conceived by Euclid in c. 300 BC, there were enough dissimilarities to suspect that some truths of the world could be falling through the cracks. For example, Earth isn’t a perfect sphere; mountains aren’t perfect cones; and perfect cubes and cuboids don’t exist in nature. Yet we seem perfectly okay with ‘solving’ problems by making often unreasonable approximations. Which one is the imperfect shadow here?

A lecture delivered by Bernhard Riemann, a student of Gauss’s at the University of Gottingen, in June 1854 put his teacher’s suspicions to rest and showed that Euclid’s shapes had been the imperfect shadows. He’d done this by inventing the mathematical tools and rules to describe a geometry that existed in more than three dimensions and could deal with curved surfaces. (E.g., the three angles of a Euclidean triangle add up to 180º – but draw a triangle on the surface of a sphere and the sum of the angles is greater than 180º.) In effect, Euclid’s geometry was a lower dimensional variant of Riemannian geometry.

But the extent of Euclidean geometry’s imperfections only really came to light when physicists* used Riemann’s geometry to set up the theories of relativity, which unified space and time and discovered that gravity’s effects could be understood as the experience of moving through the curvature of spacetime. These realisations wouldn’t have been possible without Gauss wondering why Euclid’s shapes made any sense at all in a world filled with jags and bumps. To me, this illustrates a fascinating kind of a near-miss: one where real-world objects were squeezed into mathematical rules so we could make approximate real-world predictions for over 2,300 years without really noticing that most of Euclid’s shapes looked nothing like anything in the natural universe.

*It wasn’t just Albert Einstein. Among others, the list of contributors included Hendrik Lorentz, Henri Poincare, Hermann Minkowski, Marcel Grossmann and Arnold Sommerfeld.

Featured image credit: Pexels/pixabay.

Weyl semimetals make way for super optics

In 2015, materials scientists made an unexpected discovery. In a compound of the metals tantalum and arsenic, they discovered a quasiparticle called a Weyl fermion. A quasiparticle is a packet of energy trapped in a system, like a giant cage of metal atoms, that in some ways moves around and interacts like a particle would. A fermion is a type of elementary particle that makes up matter; it includes electrons. A Weyl fermion, however, is a collection of electrons that behaves as if it is one big fermion – and as if it has no mass.

In June 2017, physicists reported that they had discovered another kind of Weyl fermion, dubbed a type-II Weyl fermion, in a compound of aluminium, germanium and lanthanum. It differed from other Weyl fermions in that it violated Lorentz symmetry. According to Wikipedia, Lorentz symmetry is the fact that “the laws of physics stay the same for all observers that are moving with respect to one another within an inertial frame”.

Both ‘regular’ and type-II Weyl fermions can do strange things. By extension, the solid substance engineered to be hospitable to Weyl fermions can be a strange thing itself. For example, when an electrical conductor is placed within a magnetic field, the current flowing through it faces more resistance. However, in a conductor conducting electricity using the flow of Weyl fermions, the resistance drops when a magnetic field is applied. When there are type-II Weyl fermions, resistance drops if the magnetic field is applied one way and increases if the field is applied the other way.

In the case of a Weyl semimetal, things get weirder.

Crystals are substances whose atoms are arranged in a regular, repeating pattern throughout. They’re almost always solids (which makes LCD displays cooler). Sometimes, this arrangement of atoms carries a tension, as if the atoms themselves were beads on a taut guitar string. If the string is plucked, it begins to vibrate at a particular note. Similarly, a crystal lattice vibrates at a particular note in some conditions, as if thrumming with energy. As the thrum passes through the crystal carrying this energy, it is as if a quasiparticle is making its way. Such quasiparticles are called phonons.

A Weyl semimetal is a crystal whose phonon is actually a Weyl fermion. So instead of carrying vibrational energy, a Weyl semimetal’s lattice carries electrical energy. Mindful of this uncommon ability, a group of physicists reported a unique application of Weyl semimetals on June 5, with a paper in the journal Physical Review B.

It’s called a superlens. A more historically aware name is the Veselago’s lens, for the Russian physicist Viktor Veselago, who didn’t create the lens itself but laid the theoretical foundations for its abilities in a 1967 paper. The underlying physics is in fact high-school stuff.

When light passes through a rarer medium into a denser medium, its path becomes bent towards the normal (see image below).

Credit: Wikimedia Commons
Credit: Wikimedia Commons

How much the path changes depends on the refractive indices of the two mediums. In nature, the indices are always positive, and this angle of deflection is always positive as well. The light ray coming in through the second quadrant (in the image) will either go through fourth quadrant, as depicted, or, if the denser medium is too dense, become reflected back into the third quadrant.

But if the denser medium has a negative refractive index, then the ray entering from the second quadrant will exit through the first quadrant, like so:

The left panel depicts refraction when the refraction indices are positive. In the left panel, the 'green' medium has a negative refractive index, causing the light to bend inward. Credit: APS/Alan Stonebraker
The left panel depicts refraction when the refraction indices are positive. In the left panel, the ‘green’ medium has a negative refractive index, causing the light to bend inward. Credit: APS/Alan Stonebraker

Using computer simulations developed using Veselago’s insights, the British physicist J.B. Pendry showed in 2000 that such mediums could be used to refocus light diverging from a point. (I highly recommend giving his paper a read if you’ve studied physics at the undergraduate level.

Credit: APS
Credit: APS

This is a deceptively simple application. It stands for much more in the context of how microscopes work.

A light microscope, of the sort used in biology labs, has a maximum zoom of about 1,500. This is because the microscope is limited by the size of the thing it is using to study its sample: light itself. Specifically, (visible) light as a wave has a wavelength of 200 nanometers (corresponding to bluer colours) to 700 nanometers (to redder colours). The microscope will be blind to anything smaller than these wavelengths, imposing a limit on the size of the sample. So physicists use an electron microscope. As waves, electrons have a wavelength 100,000-times shorter than that of visible-light photons. This allows electron microscopes to magnify objects by 10,000,000-times and probe samples a few dozen picometers wide. But as it happens, scientists are still disappointed: they want to probe even smaller samples now.

To overcome this, Pendry had proposed in his 2000 study that a material with a negative refractive index could be used to focus light – rather, electromagnetic radiation – in a way that was independent of its wavelength. In 2007, British and American physicists had found a way to achieve this in graphene, which is a two-dimensional, single-atom-thick layer of carbon atoms – but using electrons instead of photons. Scientists have previously noted that some electrons in graphene can flow around the material as if they had no mass. In the 2007 study, when these electrons were passed through a pn junction, a type of junction typically used between semiconductors in electronics, the particles’ path bent inward on the other side as if the refractive index was negative.

In the June 5 paper in Physical Review B, physicists demonstrated the same phenomenon – using electrons – in a three-dimensional material: a Weyl semimetal. According to them, a stack of two Weyl semimetals can be engineered such that the Weyl fermions from one semimetal compound can enter the other as if the latter had a negative refractive index. With this in mind, Adolfo Grushin and Jens Bardarson write in Physics:

Current [scanning tunnelling electron microscopes (STMs)] use a sharp metallic tip to focus an electron beam onto a sample. Since STM’s imaging resolution is limited by the tip’s geometry and imperfections, it ultimately depends on the tip manufacturing process, which today remains a specialised art, unsuitable for mass production. According to [the paper’s authors], replacing the STM tip with their multilayer Weyl structure would result in a STM whose spatial resolution is limited only by how accurately the electron beam can be focused through Veselago lensing. A STM designed in this way could focus electron beams onto sub-angstrom regions, which would boost STM’s precision to levels at which the technique could routinely see individual atomic orbitals and chemical bonds.

This is the last instalment in a loose trilogy of pieces documenting the shape of the latest research on topological materials. You can read the other two here and here.

Amorphous topological insulators

A topological insulator is a material that conducts electricity only on its surface. Everything below, through the bulk of the material, is an insulator. An overly simplified way to understand this is in terms of the energies and momenta of the electrons in the material.

The electrons that an atom can spare to share with other atoms – and so form chemical bonds – are called valence electrons. In a metal, these electrons can have various momenta, but unless they have a sufficient amount of energy, they’re going to stay near their host atoms – i.e. within the valence band. If they do have energies over a certain threshold, then they can graduate from the valence band to the conduction band, flowing throw the metal and conducting electricity.

In a topological insulator, the energy gap between the valence band and the conduction band is occupied by certain ‘states’ that represent the material’s surface. The electrons in these states aren’t part of the valence band but they’re not part of the conduction band either, and can’t flow throw the entire bulk.

The electrons within these states, i.e. on the surface, display a unique property. Their spins (on their own axis) are coupled strongly with their motion around their host atoms. As a result, theirs spins become aligned perpendicularly to their momentum, the direction in which they can carry electric charge. Such coupling staves off an energy-dissipation process called Umklapp scattering, allowing them to conduct electricity. Detailed observations have shown that the spin-momentum coupling necessary to achieve this is present only in a few-nanometre-thick layer on the surface.

If you’re talking about this with a physicist, she will likely tell you at this point about time-reversal symmetry. It is a symmetry of nature that is said to (usually) ‘protect’ a topological insulator’s unique surface states.

There are many fundamental symmetries in nature. In particle physics, if a force acts similarly on left- and right-handed particles, it is said to preserve parity (P) symmetry. If the dynamics of the force are similar when it is acting against positively and negatively charged particles, then charge conjugation (C) symmetry is said to be preserved. Now, if you videotaped the force acting on a particle and then played the recording backwards, the force must be seen to be acting the way it would if the video was played the other way. At least if it did it would be preserving time-reversal (T) symmetry.

Physicists have known some phenomena that break C and P symmetry simultaneously. T symmetry is broken continuously by the second law of thermodynamics: if you videographed the entropy of a universe and then played it backwards, entropy will be seen to be reducing. However, CPT symmetries – all together – cannot be broken (we think).

Anyway, the surface states of a topological insulator are protected by T symmetry. This is because the electrons’ wave-functions, the mathematical equations that describe some of the particles’ properties, do not ‘flip’ going backwards in time. As a result, a topological insulator cannot lose its surface states unless it undergoes some sort of transformation that breaks time-reversal symmetry. (One example of such a transformation is a phase transition.)

This laboured foreword is necessary – at least IMO – to understand what it is that scientists look for when they’re looking for topological insulators among all the materials that we have been, and will be able, to synthesise. It seems they’re looking for materials that have surface states, with spin-momentum coupling, that are protected by T symmetry.

Physicists from the Indian Institute of Science, Bengaluru, have found that topological insulators needn’t always be crystals – as has been thought. Instead, using a computer simulation, Adhip Agarwala and Vijay Shenoy, of the institute’s physics department, have shown that a kind of glass also behaves as a topological insulator.

The band theory described earlier is usually described with crystals in mind, wherein the material’s atoms are arranged in a well-defined pattern. This allows physicists to determine, with some amount of certainty, as to how the atoms’ electrons interact and give rise to the material’s topological states. In an amorphous material like glass, on the other hand, the constituent atoms are arranged randomly. How then can something as well-organised as a surface with spin-momentum coupling be possible on it?

As Michael Schirber wrote in Physics magazine,

In their study, [Agarwala and Shenoy] assume a box with a large number of lattice sites arranged randomly. Each site can host electrons in one of several energy levels, and electrons can hop between neighboring sites. The authors tuned parameters, such as the lattice density and the spacing of energy levels, and found that the modeled materials could exhibit symmetry-protected surface currents in certain cases. The results suggest that topological insulators could be made by creating glasses with strong spin-orbit coupling or by randomly placing atoms of other elements inside a normal insulator.

The duo’s paper was published in the journal Physical Review Letters on June 8. The arXiv preprint is available to read here. The latter concludes,

The possibility of topological phases in a completely random system opens up several avenues both from experimental and theoretical perspectives. Our results suggest some new routes to the laboratory realization of topological phases. First, two dimensional systems can be made by choosing an insulating surface on which suitable [atoms or molecules] with appropriate orbitals are deposited at random (note that this process will require far less control than conventional layered materials). The electronic states of these motifs will then [interact in a certain way] to produce the required topological phase. Second is the possibility of creating three dimensional systems starting from a suitable large band gap trivial insulator. The idea then is to place “impurity atoms”, again with suitable orbitals and “friendly” chemistry with the host… The [interaction] of the impurity orbitals would again produce a topological insulating state in the impurity bands under favourable conditions.

Agarwala/Shenoy also suggest that “In realistic systems the temperature scales over which one will see the topological physics … may be low”, although this is not unusual. However, they don’t suggest which amorphous materials could be suitable topological insulators.

Thanks to and its nonexistent autosave function, I had to write the first half of this article twice. Not the sort of thing I can forgive easily, less so since I’m loving everything else about it.

GM: confronting contradictions

There was a rash of articles published online recently – such as this one – about how the adult human mind, when confronted with information that contradicts its existing beliefs, does not reorganise what it knows but rejects the information’s truthfulness itself. During political conversations, this aspect of how we think and learn is bound to influence both the way opposing parties argue and the effects of propaganda on people. However, this notion’s impact seems to me to be more dire w.r.t. the issue of genetically modified (GM) crops.

Even when confronted with evidence in support of GM crops from the scientific literature, anti-GM activists reflexively take recourse in the deficiencies inherent in the scientific method, even if the deficiencies themselves are well-known.

In the specific example of GM mustard, there is no clear answer: the variant developed by Deepak Pental & co. has lower yield than some non-GM varieties but higher pest-resistance and is easier to breed. As a result, any single discussion of GM mustard’s eligibility to be a food crop (it hasn’t been released into the market yet) should address its pros and cons together instead of singling out its cons.

It would seem anti-GM activists are aware of this pressure because whenever scientists raise the pros of GM mustard, the activists’ first, and often last, line of reasoning is to quote even other studies. They are in turn rebutted by more studies, and the backs and forths go on until the entire debate becomes hinged on disagreements over minutiae. Granted, allowing bad GM crops to be commercialised can have deadly consequences. But this is also true of a score other enterprises in which we are happy to go along with approximations. Why the selective outrage?

It can’t be that farmer suicides touch a nerve because they are driven not just by crop failure but also by crop insurance, grain storage/distribution and pricing indices (such as the differences between rural CPI and MSP). Estimating these three factors is a task ridden with inaccuracies, many ill-supported assumptions and, frequently, corruption. However, we don’t seem to have raged against them with as much intensity as we have against GM mustard. We should have because of what Harish Damodaran eloquently expressed in The Indian Express on June 1:

Why is there so much opposition to a technology developed, after all, by Indian scientists in the public sector? Yes, the original patent for the [Barnase-Barstar-Bar hybridisation] system was filed by Plant Genetics Systems (now part of Bayer CropScience), but the CGMCP scientists improved upon it, for which they obtained patents (three US, two Canadian, one European Union and Australian each). Yet, we see no value in their work. The opponents — from the so-called Left or the Right — haven’t even bothered to visit the CGMCP, most accessibly located in Delhi University’s South Campus, while taking time out for anti-GMO jamborees in Brussels and The Hague. All this opposition is reflective of a unique Us and Them syndrome. For “us”, nothing but the latest would do. But farmers will have no right to grow GM mustard and assess its performance on the field.

The persuasion to constantly reject one study for another and our hypocritical stand on the ownership of GM crops together suggest that the pro/anti-GM debate is going to be settled by neither of these tactics. They are both the effects of a common flaw: ideological stubbornness. Even I – being pro-GM – am inclined to consign some farmers’ opposition to GM mustard to fear-mongering by activists. Sometimes I can find something easily refuted but at others, I struggle to change my mind even if the facts are evident. Anyway, while I can’t think of what it is that we can do to make ourselves less stubborn (each to her own, perhaps?), I do think it’s important we stay aware of our biases’ impact on our public conversations.

PS: If my post seems one-sided, addressing the behaviour of only anti-GM groups, one reason is that anti-GM expression in the mainstream as well as social media overshadows pro-GM expression. I’m also biased, of course.

Featured image credit: WikimediaImages/pixabay.