Patty Mayer

In my notebook, copious illegible notes sprawl below the scribbled and underlined title ‘Patty + Denis Timeline.’ One section sticks out though, annotated with many exclamation points:

• March 29, 2015: Can’t remember the name, near Reykjavík, Iceland. Someone is arguing (Me? Mariana? Luis? Patty?) with the tour guides who do not want to let us see the Icelandic horses just a tad early so that we don’t miss our flight. Our money goes to waste; we barely make our flights back to Boston.

• August 22, 2016: Sarajevo, Bosnia and Herzegovina. Watching The Godfather on my laptop. At approx. 8:50 p.m., Patty gets bad stomach poisoning, nine hours before her flight to Miami through Istanbul. At 5:00 a.m., the taxi driver takes us to the airport, Patty conked out. Driver asks if she is alive; my hand on her neck, checking her pulse.

• November 3, 2018: On the road from Houston to Austin, TX. Weird feeling about our impromptu trip the entire morning. Patty is driving. Either on I-45 or on I-10? Just ahead of an underpass. Massive wood panel flies in toward us, spinning, gets caught underneath the car, partially detaches the bumper deflector. We take the first exit, and stay in Houston. Patty’s car needs repair. I am shaking.

• August 25, 2021: On the train from Rome to Fossato di Vico, Italy. On our way to the wedding in Gubbio. The train is empty, no announcements. Patty and I drop off at the wrong station, in Gualdo Tadino. We realize it’s the last train that day; we will miss all other connections and get stuck until the morning. The husband, the wife, and the daughter (going to Australia? London?), the only living souls in our eyesight, appear out of nowhere and drive us to Fossato di Vico.

• October 27, 2023: San Francisco, CA. Patty and I in my bed, watching Gilmore Girls: A Life in the Year. At 6:38 p.m., my apartment starts visibly shaking. I jolt out of bed and grab Patty’s arm; we need to hide quickly under a table. The earthquake stops, Patty asks if that was a loud truck passing by.

The morning before New Year’s Day, I am looking at the notes for Patty’s profile. For the past seven days, I have been going through photos, texts, emails, and diary entries, starting from the ones in mid-2012 and ending with the ones in late 2023, so that I could accurately construct the timeline of my and Patty’s friendship. I am not entirely sure what I was hoping to achieve with this investigation, to be honest. But it has surfaced an amusing pattern: Patty plus Denis plus travel always equals a close call with an undesirable, potentially catastrophic scenario.

It is even more amusing when I look at the first date in this timeline, which marks the inauspicious, potentially catastrophic beginning of our friendship. It would have been sometime in May 2012, September 2012, or October 2012; I can’t remember which of these is right, but it for sure was a Saturday, and it was the night I had my first interaction with Patty, when our paths crossed at a coed frat party and when we entered a year-long cold war against each other.

I was part of the coed fraternity and had door duty that night, guarding entrance to the library where the house members and vetted friends could chill and talk, away from other guests. Never one to be a warm presence at these crowded frat parties, I took the task seriously and used the measly little power I had to deny entry to anyone I did not know. Or that I was annoyed by. Or some combination of both.

Two girls, who were allegedly friends with other people at the house, came up to the door and said they wanted to drop off their jackets in the library. The one with slightly curly hair listed the names of the people in the house they were friends with. She looked visibly annoyed that she was having this conversation with me. The two definitely looked familiar, I thought, but I was annoyed now as well, so I said I would not let them in unless they got someone from the house to vouch for them. The one with straight hair did not say anything and just rolled her eyes.

Turns out they were friends with many of the people. Both joined the coed fraternity not long after that party, and suddenly, Patty and Mariana, the two besties everyone raved about, were now a constant presence in my life. We barely interacted after that, and when I did run into them, we exchanged only terse, cold “hey”s and went on with our lives.

It continued that way until the next summer, in 2013, when both Patty and I stayed at the house to do our internships in Boston. Everyone else, aside from two or three people we knew, left for the summer, and the rooms were rented out to Irish blokes on short-term exchange visas, who were doing their seasonal summer jobs in the day and partying at night, which included but was not limited to: puking around the house, chugging liters of beer at an impossible speed before the flaming toilet paper rolls sticking out of their asses would burn their skin, and curing hangovers with a lot of whey protein.

To survive these dire circumstances, Patty and I gave each other a chance and started hanging out that summer. Her bestie Mariana, who was doing an internship in New Jersey, came back to Boston for the July 4th weekend as well. Then, Mariana and I also gave each other a chance. Over the next few months, I became close to Patty—the next important date in the timeline being November 12, 2013, when the two of us went to see Charli XCX and Kitten at The Sinclair—and then in 2014, I became close to Mariana. Today, both of them are in my innermost circle of friends.

Two months before my investigation, right around Halloween, Patty (short for Patricia; and pronounced PUH-tee, not PA-tee) came to California for a week to visit her boyfriend Fotis, who is doing a two-year postdoc at Stanford University. It’s not often that Patty and I get to see each other these days, because she now lives in Zürich, where she is doing her PhD in Chemical Engineering. I therefore seized the opportunity and demanded that we spend one full day together in San Francisco for her interview.

We meet on a sunny but chilly Friday and take the bus to Vive La Tarte in Noe Valley where we get breakfast. The timing of Patty’s visit is most opportune because the city in October is at its campiest. Left, right, and center, dramatic Halloween decor has taken the stage and has transformed San Francisco into a real-life version of The Addams Family. Patty is visibly entertained by the city’s theatrics.

“How does this compare to Switzerland?” I ask.

“Very different,” she laughs. “I actually had a friend from Europe visit San Francisco last weekend, and she thought it was very tacky that a four-star hotel had these elaborate Halloween decorations.”

Part Venezuelan, part American, part European, Patty left her oil-and-gas corporate job at Exxon in 2020 and moved from Houston to Zürich to do a one-eighty and join the Energy and Process Systems Engineering Group, a research team at ETH Zürich focused on sustainable energy systems and sustainable chemical production processes.

“What a switch, right?” I say. “From an oil girl to a sustainability girl.”

“I really like it,” Patty adds. “I am in my third year now, and I feel more confident in my research and abilities than I did in the beginning. I wanted to move into sustainable energy for a while, so it’s really nice to be on the other side now, feeling that I understand the field and that I can contribute. I just published my first paper this summer.”

Patty’s research lies at the intersection of mathematical modeling, operations research, and optimization. Her first publication compared the economics and environmental impacts of blue and green ammonia industrial production through techno-economic analysis (which analyzes the economic performance of a commercial product or technology) and full life cycle assessment (which analyzes the environmental impact of a commercial product or technology).

Ammonia, chemically known as NH₃, is universally associated with one thing: the smell of piss. Or, for some people, the smell of New York. But industrially produced ammonia is an important commercial product, used in agriculture as a fertilizer, in wastewater treatment, in refrigeration, and in production of household cleaning products. All to say, where there is ammonia, there is money. And that means there is an entire industry dedicated to producing ammonia.

Classic production of ammonia includes gray ammonia and brown ammonia. These are the most carbon-intensive ways of making ammonia and rely heavily on fossil feedstocks, such as coal (brown ammonia) and natural gas (gray ammonia). The fossil feedstocks provide the hydrogen needed for ammonia, while the carbon from these materials gets released mostly as carbon dioxide, which is bad for the environment. Blue and green ammonia were, in response, developed as low-carbon alternatives.

The methods differ in hydrogen production. Green ammonia is produced using water electrolysis. Blue ammonia is produced using methane, a natural gas, similar to how gray ammonia is produced, but the carbon dioxide that gets released during the breakdown of methane (bad for the environment) is snatched by carbon-capture technology. There has been a lot of buzz and talk about the two colors, but it hasn’t been fully clear which of these two has better economic and environmental impacts. Enter: Patty Mayer.

“Why?” I laugh.

“I don’t know,” Patty cracks up. “Maybe it’s the feeling of contributing something good, something meaningful to the world. I like thinking about how processes can be efficient, especially for the greater good. Even in my personal life, I operate from a place of efficiency.”

That is accurate. Patty likes to optimize. Give a randomly-selected person a day off, and they will most likely use that day to relax and do nothing. Give Patty a day off, and she will fill it up with as many activities as possible. At MIT, despite the continuously brutal academic coursework (at which she excelled), Patty somehow found the motivation to wake up and go swimming at the gym on school days. When she lived in Houston, after spending the full working day at her corporate job, she then went to data bootcamp classes at night. Now, in Zürich, in addition to her PhD, she is playing tennis, doing a lot of road cycling, going on hikes, and has even done a half-marathon in April.

I think it’s fair to say that Patty is intense. But it’s the type of intensity that stems from her internal optimization mechanism, which means the intensity is almost always directed inward, strictly toward Patty, and not anyone else. She expects and demands a lot from herself and is always finding ways to extract the most value out of her mental and physical capacity.

To most people, however, she doesn’t seem intense, and that’s because her way of interacting with others is antithetical to her way of interacting with herself. In social settings and in relationships, Patty thrives when there is spontaneity, fluidity, unpredictability, and freedom of choice. The moment interactions become formulaic or systematic or encoded with unspoken social codes of conduct, she feels the need to rebel against all forms of structure. This dichotomy of hers is probably the main reason why Switzerland can’t seem to ever pass Patty’s vibe check.

“On paper,” she says, “it’s the perfect place to live. But there is just something in the culture that I cannot fully connect with. Everything is efficient, everything works, but I always feel like I am doing something wrong. Like I am breaking a rule. It’s a very rigid culture.”

Patty and I soon leave Vive La Tarte and decide that we want to spend the rest of the day in Golden Gate Park. I order a Waymo for us—it will be Patty’s first time in a self-driving car—while she is coordinating the rest of the day with Fotis, who will join us in the evening for dinner. At the intersection of Church and 24th, across from Happy Donuts, Waymo appears a few minutes later and pulls over.

Its spinning lidar dome flashes my initials, I unlock the car with the app on my phone, and Patty hesitantly opens the backseat door. The city suddenly goes from The Addams Family to The Jetsons, and starts to feel eerily a few decades ahead of time.

“Good to see you, Denis,” the car says, with its sanitized, futuristic voice.

“This is so weird,” Patty wails.

We buckle up and the screen lights up with our route and estimated driving time. Fourteen minutes.

“Fourteen minutes of this,” Patty says in disbelief.

The route to Golden Gate Park turns out to be rather hectic. Many tight turns and narrow roads and both Patty and I are on edge, but our Waymo navigates these curveballs effortlessly. The most miraculous moment happens at the intersection of Masonic and Fulton, close to Golden Gate Park.

Our Waymo signals to turn left on Fulton from Masonic and yields to the cars coming from the other direction on Masonic. I would not pay attention to the car doing a left turn usually, but this time, there is so much traffic coming from the other direction that I have no idea how we will squeeze in a left turn on a big intersection with a car programmed to respect all the speed limits. And then, the car recalibrates. The left blinker stops ticking, the steering wheel turns slightly to the right, the car instead proceeds straight on Masonic, and then takes a right on another street to effectively do a half-circle and enter the intersection from Fulton and avoid having to do a left turn. In other words, the car is optimizing.

“Holy shit,” I say to Patty in shock, “the car was literally, like, ‘I don’t have time for this.’”

Unbothered by the traffic on Masonic, the car now proceeds through the intersection on Fulton, and just like that, no left turn was taken.

“Wow,” both of us gasp.

After the ride with Waymo, we go for a long walk through Golden Gate Park and end up at the Tea House in the Japanese Tea Garden. There, we get tea, dorayaki, mochi ice cream, and find a seat at one of the tables by the stairs. Beautiful, lush greenery is around us, and the vibe would be just right if it weren’t for the ballsy squirrel, unbothered by our presence, that is aggressively trying to snatch our food.

Just when I ask Patty to tell me more about her roots, the squirrel comes up to my cup of tea, sniffs it, and my mind momentarily spirals into a crisis, wondering what the probability is of this particular squirrel carrying a deadly disease, and what the probability is of the squirrel’s tawny-brown nose transmitting this cataclysmic disease, and what my tombstone would say if said disease were to end me. ‘Killed by a sniff of a squirrel?’ Luckily, Patty is talking quickly and throwing a bunch of details at me, so I snap out of it and start writing down what she is saying.

Before I dive into these details, it might be helpful if I first provide a brief summary of Patty’s diverse life chapters. She has lived in many places throughout her life. Seven cities and four countries: Caracas (Venezuela), Cooper City (Florida, US), Cambridge (Massachusetts, US), Houston (Texas, US), Pau (France), Aix-en-Provence (France), and Zürich (Switzerland). And, that’s not counting some of the places where she had lived briefly, for internships, like Spain and Israel.

She is worldly and broad-minded as a result of these experiences. Some of that is obvious. She speaks English, Spanish, and French fluently, and is now building her foundation of German. Some of it, however, is less obvious, and I noticed it only after a few years of being friends with her, like her mastery of humor across these languages or her ability to easily recognize and adjust to unspoken social norms that most people would easily miss. All to say, Patty is an adept social and cultural chameleon. But it’s not a skill that she had developed intentionally, and if you ask her, it’s a skill that makes her resourceful but at times disoriented as well.

“My mom told me that, even as a kid, I had the ability to morph myself into different personalities. I think that’s why it has been confusing for me to know what I truly want sometimes,” Patty says.

This lifelong soul-searching most likely originated from Patty’s discomfort with answering a question that, for many of us, is fairly simple. Where is she from?

“I never knew how to answer that question,” she says. “I think that made me feel quite different from other people.”

It’s a difficult question to answer not only because Patty grew up in Venezuela as a kid and then moved to the US, but because, on top of that, she has an additional layer of identity: Patty and her family are Latin American Jews. Patty is 99% Ashkenazi Jewish, as proven by her 23andMe, which means she is a descendant of the Jewish ancestors that had migrated from southern Europe to western and northern Europe in the Middle Ages. A few centuries and many generations later, her grandparents left Europe for Venezuela, and then just a few decades later, her parents—along with Patty—left Venezuela for the United States.

“As I got older, especially in the last few years, I became more aware of this identity. For a very long time, I had repressed it, but I am starting to realize that the only identity I can confidently pinpoint, when people ask me who I am or where I am from, is Judaism. It’s been the only identity that has been a constant in my life.”

“It’s interesting,” I add, “because in my mind, I always perceived you as Hispanic. But I am guessing that you don’t fully see yourself that way. Neither fully Hispanic nor fully American Jewish?”

“I think that’s right,” Patty answers. “I identify with being from Venezuela, and I identify with being Jewish, and I identify with growing up in the US, but I think what feels like the most essential part of me is being a very specific subset of all this: Latin American Jewish.”

Patty does have a tight support system that helps bring levity to her soul-searching process, in part because the people making up her support system have caught the same nomadic bug. Her parents live in Florida, her youngest sister Melanie lives in New York, her middle sister Gabby lives in Washington D.C., her boyfriend Fotis has recently moved to California for a two-year postdoc, and Mariana—who overlapped with Patty in Zürich for some time—has recently moved to Madrid. And, of course, many other friends, including me, fit this pattern as well: we are dispersed across different locations, making a global web of Patty’s friends.

It’s not easy to manage a cross-continental support system, but Patty handles it well, even though Patty herself doesn’t think that. Her friendship with Mariana, in particular, is the type of close-knit relationship that, I think, is rare in Western cultures and that transcends physical distance. Patty and Mariana exemplify many core tenets of modern female friendship: they understand each other, they share many interests, they allow each other to be authentic, they like to experience novelty together, and they are not afraid to tell each other when one of them is acting like a pain in the ass.

What is unique in their relationship is that, despite getting the same degrees in school and doing similar internships and being part of the same social circles for a long time, each stayed in her own lane and helped the other one become a better version of herself. For Mariana, having a friend in Patty meant having a blueprint for confidently building an identity at the intersection of Latin America and the United States. For Patty, having a friend in Mariana meant having a role model for excelling academically and professionally.

“Would you say she has been a big part of your life?” I ask Patty.

“For sure,“ Patty smiles. “We have evolved into different people after school, and maybe the one drawback of our friendship is that we’re not good at talking about how we feel, but it means a lot to me that we can continue being close friends. I owe a lot of my success to her. She always pushed me to understand things to the n-th degree. She never accepted an answer that was simply good enough, she wanted to understand every detail. And she made me do the same.”

We leave the Tea House and head back to my place, going through Golden Gate Park once again. I have had Florence + The Machine on my mind the entire day because Patty told me about wanting to see her at Zürich Openair, and I suddenly remember the line from her song “Only If For A Night” when Florence says “and I did cartwheels in your honor.” I ask Patty, who used to do gymnastics as a kid, to do cartwheels on the grass while I take photos of her in motion. I am just about to give a lengthy monologue on why I think this is a good idea, even if it came out of left field, but, true to her character, Patty doesn’t ask any questions and just goes with it.

Now, I would be remiss to not ask Patty about another person in her support system: her boyfriend Fotis. He is the reason why she is here in California, after all, and why her life in Zürich has been energized by a sense of permanence. Patty met Fotis in Zürich through none other than Mariana, who worked with Fotis in the same lab and in the same office at ETH Zürich.

“But it wasn’t at one of their lab parties where you connected, right?” I ask.

“No, it was actually a ski trip,” Patty says. “I knew him already, I knew that he was Mariana’s office mate. But we happened to coincide on a ski trip one weekend. We were both with our own group of friends. I was waiting for the cable car, and then I heard someone calling my name. I turn around, and it’s Fotis, with a broken clavicle. He fell and needed to go to the hospital.”

“That’s how you guys got together?”

“Yeah,” Patty laughs. “I mean, I wasn’t going to just leave the guy alone there. I went to the hospital with him. And, yeah, on the way to the hospital, we exchanged numbers and it just took off from there.”

It actually is not a surprising story. For two reasons. Number one, Patty is one of those people whose relationships have all started organically, off dating apps, when she least expected it, in the most unusual scenarios. Number two, it’s in these most unusual scenarios that Patty drops her internal optimization mechanism and just goes with the flow, easily and effortlessly. I was always envious of her ability to do that.

“Compared to previous relationships, how is this one?” I ask.

“It’s the healthiest relationship I’ve had so far,” she smiles. “I feel like I was always attracted to very challenging guys before. With Fotis, it’s different. It’s easy.”

Later, back at my place, Patty and I have two hours to kill before we have to meet up with Fotis and other friends, so we make my bedroom cozy and turn on Gilmore Girls: A Year in the Life. Lorelai is just about to tell Rory about her infamous speech at the memorial get-together for Richard when my apartment starts shaking. I jolt out of bed and grab Patty’s arm, thinking that we need to stand below a door frame, but then I remember reading that door frames are not necessarily safe so maybe it’s better that we hide under my desk, but the desk is too small for both of us, and that’s where my train of thought stops because the earthquake has stopped as well.

“Was that a loud truck?” Patty asks casually, still snuggled under the weighted blanket.

“No,” I laugh and pause the episode, “that was definitely an earthquake.”

3.7 magnitude earthquake, two kilometers north-northeast of Millbrae, 11.6 kilometers deep, effectively below the San Francisco International Airport. To be precise.

“Huh,” she adds, amazed. “That was my first earthquake.”

We are both silent for a bit, waiting to see what happens next.

“Chocolate?” I ask.

Patty nods. I bring the pistachio dark chocolate bark that she had bought in Switzerland, and we continue the episode.