Single Photon Interference
On trading nationalities
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SINGLE PHOTON INTERFERENCE
The moment we leave Heathrow airport, I am suddenly more American than I have been all year.
In the airport, I am not. The customs machine struggles with my Croatian passport as much as the American one that my co-worker put through a whole wash cycle. When I see the agent, they give me the kind of side eye that I have, in the last fifteen years, grown accustomed to in the United States. It’s not quite suspicion, more like mild annoyance at dealing with yet another foreigner’s document, a reminder that some of us are not quite deserving of the conveyor belt of scanning and stamping and check-marking but we’re still somehow hanging around.
My Heathrow mishap may have nothing to do with my nationality and it could have just been bad luck, but I am primed to take it personally. Being surveilled (how many sets of fingerprints and face photos of me have accumulated in government databases over the years?) and classified (as a citizen, resident or other) and otherized (quite literally for about 12 years my immigration status was “other”) all the time means that you internalize those categories. You start to itch to self-sort even when what’s happening is a more mundane glitch in the system. Or at least I do.
Leaving the airport renders the structure of state-imposed borders a little less visible and, as I used to travel very frequently while my partner and I maintained a long distance relationship, I feel overly comfortable and definitely overly confident as we emerge into a train station. I roll my carry-on bag to the edge of the platform, like I know exactly where we’re going and like it sort of doesn’t even matter. And then it kicks in, the Americanness.
The trains here are smaller and squatter than in New York. All the station names sound like twee tongue twisters. They say “way out” instead of “exit” here. There are too many references to dukes and earls and barons. “This whole country may as well have been made up,” I tell my partner when a discussion of crumpets breaks out in our group. Someone recommends going to a “cream tea” and we’re all pronouncing “scone” funnily.
We just got here and I am already ready to be over it, purely based on the fact that we’re not in New York anymore and New York is now where I say I am from. The next day, when one of my London colleagues raises an eyebrow at the fact that everyone in the New York newsroom lives in Brooklyn despite our office being in Manhattan, I wait less than half a beat to assert that there is “no reason to ever live in Manhattan”. My allegiance to Brooklyn is as brash in its newness as the accents of my husband’s extended family, who are actually from here.
The closer we get to the hotel the more the trains fill up with soccer fans, clearly coming home after a game, red in the face from both beer and the grip of scarves in their team’s colors wrapped around their necks. In one train station, an AC Milan chant in Italian breaks out. There is banging and yelling and clapping though, as we later learn, the local team, Chelsea, had won the game. Immediately I betray myself as a fake American because the noise makes me nostalgic about “back home.” I whisper to my partner about HNK Rijeka and Armada, the team my father loves and its loyal and raucous fans.
Growing up in Croatia, close to the Italian border, I was always looking up to this local version of soccer hooligans, not dissimilar from the AC Milan crowd. In my early twenties I did a bit of yelling at games of my own, especially during visits with my family after I had already moved to the United States. The crass noise and nearly aggressive energy of it all were an unexpectedly effective way to connect me to my culture fast and hard and without overthinking.
There are cultural and historical references for rioting at or after sporting events in the United States too, and American sports fans certainly do take their sports as seriously as possible, but the European soccer fan feels distinct to me. Probably because I was destined to be one by the virtue of being born Croatian, and all American sports still mostly confuse me.
At the hotel check-in, I suspect I may be American again, but there is always the issue of my name. The K in Karmela, the diacritic that’s missing over the C in my given last name, the G in the last name I chose to share with my partner when we got married, they all confuse regularly. In an idealized version of the United States, the infamous “melting pot” model, this word salad of names would make me more American than all the James’s Smith, but in reality it just makes it hard for me to make reservations over the phone and invites raised eyebrows when I first introduce myself. I suspect the Callaghan part would go over more easily if it weren’t hyphenated or if my first name was Erin or Mallory, but even those would have, at some point in American history, signaled trouble for those who bore them.
Early 20th century advert for a boat from Rijeka, where my family is from, to the United States, from the collection of City Museum of Rijeka
Popular science outlets, like the one I work for, will often gladly feature stories about how in quantum mechanics a particle, like an electron, can exist in two places at once. This is evidenced in experiments where a single electron or a single photon (a particle of light) passes through two slits at once, something that sounds like nonsense but nothing more sensical has been agreed upon by physicists for almost a hundred years.
In the experiment, an electron is fired towards a barrier with two narrow slits that allow it to pass through and hit a detector on the barrier’s other side. According to classical intuition and reasoning no amount of repeated experiments should result in the detector finding the electron anywhere other than directly behind one of the slits. Yet, that is not quite what happens. In fact, a fairly complex pattern emerges with detection events at many places behind the space between the slits where the electron should not have been able to go. Quantum theory, which does primarily reign over objects as small as single particles, suggests that the electron passed through both at once, each time acting as a wave and interfering with the wave emerging from the other slit after exiting its own.
You can imagine making waves by dropping a small stone into a pond then pushing one whole rippling front through two narrow slits. They would clash on the other side of the barrier. You can imagine the shimmer of water as the crests and troughs overlap and fight for whether water will be high or low. An electron or a photon is much harder to visualize, but it does something similar. It is important to note, however, that the particle does not split in half as we know that it is impossible to break an electron or a photon and this has been tested in experiments many times. The trick a particle like an electron plays is completely quantum and there is no classical language or analogy for it.
The electron that can jam itself through two narrow passageways at once then meet itself in the middle is not so much aspirational as much as I, at times, feel a kinship with it. For one version of me, and all version of me are somehow inhabiting a mix of many ways of being at once, slit 1 requires me to wiggle my way through the box of either wife (green card worthy) or exceptional talent or scholar (visa worthy), and slit 2 narrows my identity down to who I was at 16 (small, confused, sad) when I left home or, even more intimidatingly, who my parents think I should be at 30 (mental healthy, childbearing, womanly).
When I am yelling Croatian into my phone on the street during my lunch break and my mom is eating her late night snacks on the other side of the screen, I am in that classically forbidden detector middle. When I am at my family’s cabin in the woods frying potatoes and a relative stops by to ask whether it’s scary to live in a “crime-ridden place like Brooklyn”, I find myself in that middle again. As Activist-novelist Jessica Gaitán Johannesson told Electric Lit, moving between countries and being multilingual can lead to feeling like
“You’re never fully a stranger, but you’re also never fully at home.”
The wave-on-wave clash is something I have learned to brace myself for, but it certainly never brings clarity. In fact, it often reminds me that part of what landed me into this type of ambiguity and mixedness is that I made a choice to live in America, and many more choices after that.
I return to the idea of American-ness and what it means for the kind of privileged immigrant like me in these letters with yearly regularity. Usually, it is because there is always something bigger than me that envelops me and naturally invites a small identity crisis. Endless visa renewals, xenophobic incidents in the small town where I went to graduate school, the long legal anxiety that was obtaining my permanent residentship, the uprisings and unrests following racist actions of the police state a few summers ago (and then after that), they all put the thought back into my head - what does it meant to want to be American or to be proud of working towards it successfully?
And now, this London trip, where I felt like an American foreigner rather than a Croatian one, and this emotional swap threw me into moments of shameful feelings of superiority instead of equally misguided moments of feeling small.
****
Pointing out and laughing about differences between American and English culture is something of a favorite pastime in the office I work in. Only two of my colleagues are transplants from the London office, and one was born in the United States, but that is just enough for discussions of tater tots, Twinkies, brollies, how many things you can mean when you sign your email with “cheers” or whether the size of something should be compared to an “aubergine” or an “eggplant” to be a mainstay. Colleagues based in London will often message those of us in New York to ask whether we say “double whammy” on our side of the ocean or if “rock pooling” is a meaningful phrase for American nature aficionados.
The dynamic is funny, but it is mostly such because we are all educated, mostly white, mostly middle class people with stable paychecks and homes. Who we are both lowers the stakes of poking fun at each other’s culture, and gives us a shared sense of safety because we can reasonably assume that our politics are similarly liberal and progressive. Political and other scandals in the UK have lit up our Slack and email channels at times and the death of Queen Elizabeth II certainly felt fraught across the company, but most of the time we have treated our cultural differences as an inane curio.
The London trip disrupted that somewhat. It gave the UK citizens among us a chance to air grievances about American prices, taxes and regulations surrounding work, education and marriage. And it invited the rest of us to engage in comparisons of infrastructure and social class that cut deeper than fighting about what sherbert is. Comments about London being cleaner than New York or fewer people experiencing houselesness all carried more weight than disputes over candy. There were very few gender neutral bathrooms and an overwhelming abundance of colonial monuments, but I struggled to find words to comment on that much more than I would usually struggle to deliver a tract on mince pies or Yorkshire puddings.
It just so happened that we were in London when the New York Giants played the Green Bay Packers there as part of the NFL's attempt to spread on the European market. My partner, a real New Yorker, was bewildered by how many people in London had heard of and wanted to root for Green Bay instead of his famous hometown. We bumped into a few of them and they all quickly revealed themselves as Americans.
In a gelato shop I helped a ruddy-cheeked woman called Nancy, who struck me as the kind of Midwestern that would have been helping me out in a store in Illinois just a few years prior, order her ice cream despite the lack of an easy to understand scoop system. I absentmindedly ordered a chocolate sorbetto after she was done, absentmindedly because thinking about whether she thought I was American and whether the gelato server identified her and me as the same preoccupied me.
When we talk about funny American food in the office, I am sometimes a bit too smug for my own good. I take pride in having been foreign and confused and now being less visibly foreign and less overall confused than other non-Americans in my midst. This is an irrational kind of pride, the kind you get trapped in in the same way you get trapped in thinking a passport glitch is normal because things are normally difficult for foreigners.
I read Fariha Roisin writing about New York and knowingly nod when she says that
“We’ve all bought into this idea of New York, much like we’ve bought into the idea of the American Dream.”
And continues to describe
“How neighborhoods are lined with bags of trash, a hellscape of smells and heat bouncing off the pavement, but dares you to scream, it conditions you to like it. An emblem of America is its dissonance from itself — what it purports to be versus what it is. I had not noticed it as much before, not like this, maybe because of the patina of the city, the excessive shine—the romance we have from the infamous Washington Square arch to motherfucking Zabars — we’ve been sold the mythology of New York, concrete jungle where dreams are made of, we’ve been sold America.”
But I still love New York, probably because I am the correct demographic and correctly classed to do so. Certainly, I know social and political science and lived experience all strongly point towards the American Dream being a myth at best and a scam at worst, but I will still talk about freedoms that New York affords to “people like me”, about the refreshing directness and the business that can so easily be unfriendly and alienating if you’re not “people like me”, about the old school New Yorkers who are a lovable curio, but in many cases only if you chose to put their affect over their politics. And Roisin is right, this is not just a New York thing, it’s something that’s replicated on the scale of the whole country with its purported commitments to liberty and its plethora of problematic, but iconic and visually inescapable avatars to choose from.
There is no virtue in having assimilated, but assimilation always seems simpler and quicker than holding complexity within yourself all the time, so it feels like a skill or an achievement. That self-interference wave is so disruptive in part because it is a reminder of how fragile and artificial that pride is. How it serves to take you, a whole person, then chunk you up into categories that both make you feel less whole and less likely to feel solidarity for your peers. Certainly this is at least in part why so many employers insist that your coworkers have to be your friends, that your profession is “your people” and your company a second family. First the state breaks up your identity, next capitalism offers you a substitute while you’re confused and fragmented and you end up self-trapping in wanting to be a good worker. And what is more American than being loyal to your work?
As Hannah Zaheer writes about her experience working at Abercrombie and Fitch, a company that intimidated me tremendously on some of my first trips to an American mall a few decades after Zaheer’s time there,
“The privilege of calling myself “all-American” made me complicit with a system that I did not fully understand and imprinted upon me values I would later reject. In a twisted way, I cannot think of a more appropriate orientation to America.”
Often, I complain about how I am too Croatian in America and too American in Croatia, but as time goes on and the world catches literal and figurative fires more and more, I am starting to understand that it’s these categories and labels themselves that are insufficient and not necessarily myself.
The problem with wanting to be American is that the construction of American identity is a racist, colonial, capitalist project. The problem with feeling superior in London is that the United Kingdom is also a racist, colonial, imperial project that America just managed to leave and out-do. Even in my home country, our identity as Croats is heavily marked by wars and often defined in opposition to other nationalities of cultures, from centuries old stories about fighting “demonic” Turkish invaders to our flirtations with fascim in World War II to never-ending tails of the Independence War during which I was born. (In a great piece for Vittles Natasha Tripney notes how wars in the Balkans led to a decline of so-called Yugoslav cafes and gave rise to a more divided idea of what dish belongs to which nation. I imagine at that time no ex-Yugoslav immigrants were laughing about the difference between burek and pita zeljanica.) The idea of being proud of a nationality rather than a culture, of subscribing to membership in a state rather than a community, is not one that can bring more than feelings of internal clashes or desires to wash out and wash away somebody else.
****
You can only push a metaphor so hard before it becomes nonsense, but the fact that quantum mechanics reveals that everything, not just electrons and photons, can sometimes behave as a wave offers imagery that is sometimes too good to pass up. In extreme situations, like at temperatures as small as millionths of the temperature of interstellar space, a group of atoms will all stop buzzing around like they do in your cup of tea or a pot of bubbling, boiling water, and become long, spread out, slow waves that all overlap. Hundreds of thousands of atoms or molecules will forgo their individuality and combine into one massive matter wave, an entity where they are not just acting in unison but truly become one indistinguishable part of a chunk of undulating quantum stuff. This is an extreme image, and I don’t mean to advocate for sameness. I do mean to, however, advocate for allowing for overlaps.
Quantum states can be mixed and they can have different parts or modes that are inextricably linked, through entanglement or just being superpositions. And they can, if you don’t force them to collapse into just one thing, oscillate and self-interfere and touch edges with other states. If everything is a bit of a wave, then everything is sort of always on the edge of making up the same pond, or at least a system of waters that are sometimes deep and wide and sometimes trickling and shallow. In his book Fear of a Black Universe physicist Stephon Alexander uses similar imagery when it comes to describing every piece of matter in our universe as an excitation in an invisible but all permeating quantum field:
“We are tethered to the fundamental fabric of the universe. All the particles that comprise us are quantum vibrations of the same quantum fields that extend across the universe.”
It is cheesy and predictable and cringe to say that we’re all made of the same stuff and that we’re all connected. But on some very basic level, some aggressive oversimplification of all ways in which we are not just a sum of particles, it is also true.
****
A few years ago, finding myself in a place that, ironically, used to be Europe, but isn’t anymore, and feeling anything other than European would have made me accuse myself of having betrayed the label I was born into. I would be writing yet another paragraph about waking up in the morning and having my first thoughts be in English or about not having successfully forced my partner to learn Croatian. I still think about those things, but the labels feel more arbitrary and more like tools and crutches than anything intrinsically valuable or virtuous. In some sense, they have betrayed me by blocking off the waters I should be able to spill into.
Earlier this fall, I baked a poppy seed roll inspired by my grandmothers for a potluck with a few local friends. One, a Russian immigrant, brought a bunch of small containers filled with zakuski from a Russian supermarket I once lived close to. We bonded over it, discussing for the billionth time how sad and wet and limp American pickles can be. A few weeks ago, my partner and I had drinks and snacks at a friends’ house, in a Chilean-French immigrant household, and I brought a bottle of Croatian Plavac to flow alongside a conversation that inevitably led us to what we as kids, back home. I was delighted to learn we had all grown up with a not-quite-American take on hot dogs, something my mom would reach for whenever we needed a quick supper and eggs and home fries or a pile of crepes seemed unfeasible.
Not surprisingly, the best food we had in London was in restaurants that were not trying to be English, where the fare was dumplings or curries instead of being beige and devoid of spice. Accessibility of this sort of “international” food is something I love about living in New York too. And it was watching Indian roommates cook, spice dabba in hand, or being invited to a Chinese friend’s house for a festival celebration or a lunar new year party that made the international label fall into the background for me years ago. The best way to overlap with someone is often to jam into a graduate-student-sized kitchen together and make a bit of a mess. Often, this is how you find both yourself and your people, no comparisons or pride necessary.
Best,
Karmela
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ABOUT ME LATELY
WRITING
I wrote a few fun big-things-big-questions type stories recently: one about the world’s largest digital camera, one about a new property of the Higgs boson that was measured during the second run of the Large Hadron Collider, and one about the possible origin of a molecule that is an “energy currency” in virtually all living cells. In some way, reporting on big questions like whether the standard model of particle physics actually works or whether life could have arisen through very fine-tuned reactions is more difficult than simply describing a large machine, but I spend a good amount of time fretting about the giant camera and whether I had done a good job describing the remarkable work of engineers and physicists that sunk years into it.
At New Scientist Live, the reason for the trip to London that I wrote about above, I introduced a half-dozen talks, facilitated a few Q&As and participated in a panel. None of this was technically writing, but it was my first real public engagement as a full-time, professional journalist. It was really heartening to see how many thousands of people showed up for the whole event, which was in itself massive and packed with interesting science.
I was also featured in an extra episode of the New Scientist podcast, recorded at New Scientist Live, where audience members asked journalists whatever they wanted. I broke out the old reliable "science is an art of approximation" line, shouted-out antibubbles, and endorsed a coconutty sloth. The experience was a bit more overwhelming than the other podcast episodes I’ve called into to talk about something I’ve reported, but I hope our team will do more interactive episodes in the future nevertheless as connecting with readers is really important.
LEARNING
How to not get discouraged by stalled progress. How to crawl out of a depressive episode for just enough hours in a day to produce the work that I promised I would.How to meet new people and remember their names. How to make small talk in a staff room, an office cafeteria, a pub, a convention center and in an Indian restaurant. How to remember that my boss is my boss even when they’re chatting me up about vegan sausage rolls.
How to go from one trip to another without getting fully disoriented. How to spend time outside in any city because I know the sun will make me happy. How to not feel guilty about not consuming culture as homework wherever I go. How to find vegan donuts wherever I go. How to not project my insecurities on people I love the most. How to say I’m hot and not take it back immediately. How to say my feelings have been hurt and not take it back immediately.
What kind of particles are inside of a proton because I got it wrong at least once this year already.
READING
This gorgeous explainer on what’s inside a proton from Quanta magazine, motivated by one of the few recent discoveries that keep changing our ideas about this particle that is fundamental to all matter.
This issue of Dirt about how all the “losers” that dominated 90s movies have been replaced by “strivers” that exemplify the current culture of always thinking you’re on the edge of turning yourself into either successful content or a successful business. In describing the wannabe slackers of today, often in one-name-as-a-title semi-autobiographical prestige sitcoms, Jameson Rich writes
The artistic quality of these works is usually as competent as the protagonist: perfectly so. But their greater impact is limited. In rejection of human weakness, in stories where all the parts of self which are not beneficial to success must eventually be excised, art betrays truth. Personhood becomes an act of branding. An artist may be representing their experience, but they do so at the expense of Experience; the specific becomes distinctly un-universal. Just because entertainment has banished the loser doesn’t mean it has become any more successful.
This somewhat terrifying story from the MIT Technology Review about using AI for assisted death. The AI part is more scary than the dying part given that most of what we’ve seen about AI in practice so far has fully replicated the human biases we have been hoping to abstract away by building these artificial “intelligences”.
Jenny Odell’s How to do Nothing which I have been really enjoying as both an exploration of stepping away from the world of work and a manifesto in favor of making that stepping away more than just physical. Odell recognizes that moving to the mountains to escape society is not the answer as wanting to disconnect from the attention and hustle economies does not absolve us of the responsibility to take care of each other. This greatly complicates the often anemic contemporary arguments about social media detoxes or return to the land by planting your own tomatoes.
Early in the book she writes about slowing down so we could care for each other better and maintain better, and that really resonated with me:
But beyond self-care and the ability to (really) listen, the practice of doing nothing has something broader to offer us: an antidote to the rhetoric of growth. In the context of health and ecology, things that grow unchecked are often parasitic and cancerous. Yet we inhabit a culture that privileges novelty and growth over the cyclical and the regenerative. Our very idea of productivity is premised on the idea of producing something new, whereas we do not tend to see maintenance and care as productive in the same way.
LISTENING
The new Ripped to Shreds record which is some of the best death metal I’ve heard recently.
Early 2000s Leonard Cohen because this was my introduction to him as a kid and I didn’t realize he wasn’t always this husky and this cheesy until years later.
A former colleague of mine, poet and activist Ashna Ali, on the Help Existing podcast, discussing invisible and chronic illness with clarity and without shame.
WATCHING
I have been loving Andor more and more with every episode and the last two installments, The Eye and Announcement, have been rich with everything that is interesting with Star Wars and more. Compared to the Book of Boba Fett and the Obi-Wan Kenobi series, this show really benefits from there being less existing lore about Cassian Andor and from not being based on Tatooine. So far the show has given us notes of noir, Fordlandia in space, an amazing heist, political intrigue, warring intelligence officers and lavish banquets with the worst vibes. The show looks fantastic with set and costume design that is impeccably Star Wars without being cartoonish or too glossy for the story’s dark tone, and after so many episodes of Clone Wars, I have been loving live action Coruscant which is not any more warm than in animation. I’m excited to see how the show will get us closer to the events of Rogue One, but mostly I want it to keep going without becoming diluted for the sake of larger franchise mythology.
While in London (for my job) and jet lagged we watched John Wick 2 and then upon returning home for exactly one night before heading to Philadelphia (for my partner’s job) we committed to the third installment of the franchise. I really liked the first movie for how mindlessly simple it was and for how clear it seemed that there was no point to it other than to showcase fights and how well Keanu Reeves has aged. The sequels are still packed with great fights and Keanu still looks good and still growls just like he knows it and at times there is a glimmer of self-awareness about how ridiculous this genre of mbie really is, but there is so much world building and bizarre mythology happening that the films just aren’t a pure kind of cool anymore. Ian McShane is an upscaled Al Swearengen and it works for him, Laurence Fishburne is clearly having a great time being almost Shakespearean, Ruby Rose is the assassin of my dreams and the dogs have the thick necks that I love, but these movies are not good - they’re a guilt pleasure at best.
EATING
Vegan junk food in Philadelphia. I forecasted to a friend that I would be eating a vegan cheesesteak sandwich in a dive bar within an hour of getting into the city and I was correct.
We were invited to a birthday party of a dear friend’s fiancee so I made a spiced apple cider cake filled with cinnamon maple ganache then coated in salted whiskey buttercream and topped with caramel stewed apples. The couple had just returned from visiting family in Ireland and the weather finally feels like fall in New York so I had some immediate inspiration for flavors and lots of fun putting it all together. I improvised basically everything so seeing everyone at the party finish a slice felt really good.
It’s soup season and I’m always making vegetable broth by pressure cooking scraps so my freezer is making it very easy for me to reach for something miso-soup adjacent whenever that feels most easy. I don’t have a fixed method or a fixed cast of mix-ins, but I will endorse tofu puffs, dumplings and leafy greens sauteed in sesame oil as very valuable additions.