It’s been exactly two years since the start of our sabbatical year away from England, and almost a year since we returned. I’m only now understanding the shape of that year and the effect it had on me, my science, and my family.

Imperial College has a competitive process for requesting sabbatical leave: you have to choose between (paid) “intellectual refreshment” and (unpaid) “personal refreshment”. Having made careful arrangements with colleagues around the world, I was granted a coveted year’s leave for intellectual refreshment, allowing my family and me to travel to Asia, North America and Europe over the course of about 13 months. I would visit and collaborate with those colleagues, start new projects, and use the time to finish my book, The Random Universe. By the time we left, I had submitted the draft manuscript but, as I discovered, there was still a lot of work to do.

We traveled through Indonesia and Korea before finally taking the overnight ferry from Busan to Fukuoka in southwestern Japan, working our way up to Tokyo. By the time we arrived, we had already had to respond to immigration bureaucracy, expert reviews of the manuscript solicited by my publisher, and a typhoon. We eventually made it to Tsukuba (つくば), a “science city”, home to a University and many Japanese government labs, including the KEK accelerator and the QUP group where I worked. (More about our Japanese stint here, and in particular about dipping into onsen culture as foreigners, and from my wife, Lisa Lucas, on our trip to see the changing leaves in Autumn.)

With English as the lingua franca of academia, and plenty of international colleagues at QUP, I didn’t have much trouble adjusting to working there, but life outside of the lab was more challenging. In particular, my incredibly brave children went to Japanese state school! Ok, they didn’t learn much Japanese — but they walked to and from school with other students (and no parents), served lunch and cleaned the school — and we connected to the culture through the families that we met. In the meantime, I finished the edits to the next-to-final version of the manuscript (and iterated toward some amazing cover art with my publisher).

Soon it was time to leave, for a much more familiar location: Long Island, just outside of New York City (I grew up in the suburbs on the other side of the City — Fort Lee, New Jersey, in an apartment overlooking Manhattan). The children took a yellow school bus each day, and we chatted with the other parents at drop-off and pick-up. I worked at the Simons Foundation’s Flatiron Institute, taking the Long Island Railroad into Manhattan (occasionally and joyously with one of my oldest friends who had migrated from NJ to LI to raise his own family). Flatiron is well-funded (even visitors get to take advantage of free Grubhub lunches) and ranges from math through astrophysics and neuroscience — I was visiting the Center for Computational Astrophysics but also collaborated with colleagues at the Center for Computational Mathematics, where I was able to start the only completely new work of the year, cashing in some of that intellectual refreshment.

It’s an amazing place, and a very different model for research (and research funding) than the universities and labs where I have spent most of my career. Though I did find that the CCA was not as friendly as I had hoped — perhaps not quite enough overlap between my ongoing projects and those of the young scientists who dominate the Center. Or perhaps just too many introverted astrophysicists (me most certainly included)… By this time, the manuscript was going through the final nit-pick phase — copy editing, completing the figures (and the extremely tedious problem of confirming their legal status), alongside fun stuff like choosing colleagues and the occasional rock star to blurb the book. But the CCA is a place, perhaps more than anywhere else in the world today, dedicated to the study of “the random universe” — and the milieu forced me to think about how I would talk and write about (and pitch) the book to everyone else. And I loved being back in New York City (despite that commute), a place that I had mostly seen, and coveted, from afar when growing up.

The final months of our year were bracketed by road trips. We left New York (via a record-breaking Yankee game) to drive down the coast, visiting relatives in Virginia, North Carolina, South Carolina and Florida, and making a side-trip to Cozumel, Mexico, to visit a family we had befriended while trapped in a hotel by that typhoon in Hiroshima. It was a classic American drive, but still a lot of work and a lot of miles and a lot of family. It felt like time to return to Europe.

As Tsukuba is to Tokyo, Leiden is a small city outside of Amsterdam, dominated by its University. It has all the beauty of its bigger neighbour, but is less seedy, more manageable — and closer to the sea. Once we settled in, my kids went to a small international school, and we met expat families from Finland, Chile, and even other Americans. And the University is home to the Sterrewacht, one of the oldest University observatories in the world, although the actual astronomy department no longer gets to use the gorgeous old observatory building, instead one of the many groups in the massive Gorlaeus building. I used the time to talk with colleagues about weak lensing — a way of using Einstein’s predictions of how mass bends the path of light rays to map the distribution of matter in the Universe, and especially its measurement by the Euclid Satellite which was just starting to produce data at the time. (It has taken a year, but these discussions are finally reaching fruition just now.)

By this time, the book was complete — nothing more that I could do except wait for it to make its way through the final production process. Nothing, except try to get people to read it. I spent hours in Leiden’s beautiful Hortus Botanicus recording and re-recording a video to advertise the book, wrote to friends and colleagues and my publisher to drum up interest, organized podcasts and blog posts.

We had felt at home from the moment we arrived, during a cold snap in early May, cycling locally and around Holland, drinking coffee along the canals, eating Dutch friets (and the occasional bitterballen). We loved it so much Lisa penned a love letter to Leiden for the New York Times. By the end of the summer, it was hard to leave. But it was time for our final road trip, down and back through Belgium, France, Switzerland, Austria, and Germany — three weeks (probably too much) camping, with highlights including an extended stay around Annecy, a hike around Mont Blanc, and a whoosh with friends down the river Aare in Bern.

Then, finally, home, refreshed in all possible ways, back to our house in London (rented out for the year), our comfy beds, the familiar sights, the kids’ old school (and old school friends), back to my much-missed colleagues and students at Imperial. The book was finished, the kids had been to three different schools, we had visited 16 countries (I haven’t even mentioned Vietnam, Cambodia, Thailand, Singapore, or Spain). As I approach my 60th birthday next week (sure to be the subject of another post) our sabbatical year has left me more open to the future and the different places it could take me, the different kinds of science I would like to do, and the different thoughts I would like to communicate.