The Uncertainty Principle, referring to a cornerstone of quantum mechanics, focuses on a mentally unstable young girl named Mia. After an unfortunate incident with her best friend in Minnesota, Mia and her family set sail permanently on a sailboat her father restored. Mia spends her time working on science experiments involving solar power. Although it’s lonely, Mia has an imaginary friend, real-life Harvard scientist Lene Hau, a Danish physicist and mathematician, to keep her company. Then the family meets an Australian family that has been living on the waves for five years. Mia is immediately attracted to their son Alby, and they quickly form a romantic relationship. However, her family is leaving and their attempt to keep in contact via satellite radio goes awry. Meanwhile her mentally ill germaphobe mother is making Mia miserable. Her dad makes arrangements for her to go to Tennessee and live with his brother. But before she leaves, Mia meets and rescues wealthy socialite Nisha who is being bullied by her dad to jump off a cliff. They quickly bond and Nisha’s dad is impressed by Mia’s scientific knowledge and wants to set her up with a lab so he can profit from her findings. Then she is kissing Nisha, when Alby shows up with his family and Mia is totally confused as to how she can be attracted to both a boy and a girl. Mia, a neurodivergent protagonist, is on a journey to discover herself and follow her destiny. The authors provide a sailing glossary and load the story with accurate information about solar technology and scientific philosophy for a very informative read.

I love love love an unconventional coming of age story and this is no exception. Poor Mia is navigating the high highs and low lows of adolescence and she has a lot on her plate.

Mia's story is engaging and entertaining. The details around sailing are evocative, as are the setting descriptions. The vivid imagery roots the reader in the setting.
Each character feels real, the result of wonderful character development. The authors certainly capture the breadth of people one might meet on an international sailing journey.
Mia learning to accept that it was a toxic friendship that contributed to her negative self-image, and not who she is as a person, was an especially wonderful aspect of this adventure.

This book definitely captured my attention. The main character was interesting and she and her mom were quite interesting characters. I do wish there were more scenes with the family and the event highlighted at the beginning (and was a clear build up) resulted in barely a few pages in the last 5% of the book.

One thing about me is I'l pick out something to read in a few weeks, forget what it's about, and then be completely shocked when I finally pick it up. So while I was pretty confused the first few chapters, I was absolutely delighted to find out that past me had set me up with a bisexual teenage adventure. Mia's journey to of discovery and acceptance - of more than just her sexuality - felt incredibly genuine and realistic for someone her age. I loved seeing her become more confident and allowing herself to feel and explore.

As some other reviewers have noted, it seems likely/obvious that Mia's mother has OCD and Mia is autistic, though the book doesn't confirm or explicitly name either of those things. While I understand how that might have felt hard to pull off with it being from Mia's POV, I do think it would be valuable for younger readers who might not be able to identify those traits as easily.

My biggest critique of this is that I felt the wrap up/ending was very sudden and too quick. One second we were leading up to the climax and the next the whole thing was over. I almost felt like I had accidentally skipped a few chapters. Despite that, I felt Mia and the cast of characters around her were charming enough to keep this a predominantly positive experience.

I enjoyed this book. It included a lot of hard subjects like mental health, family, romance and friendships. I really liked the unique concept of living on a boat, I thought that was so interesting. Overall this book was a well written and original.

After a mortifying incident in the school cafeteria, sixteen-year-old Mia is now standard on a battered sailboat with her family in the middle of the Caribbean. Her mom and dad believe that leaving everything behind is the best decision they’ve ever made, but Mia feels like she’s been kidnapped and imprisoned with no internet and no destination.

Her only hope is putting together a solar-powered satellite phone from scratch using salvaged parts so she can call her best friend and fix everything. By day, it’s island hopping. By night, Mia squeezes into a narrow bunk and talks to her imaginary friend, award-winning female scientist, Lene.

And then, two teenagers sail into Mia’s life, Alby and Nisha, promising friendship, and maybe even romance. Alby, who grew up in Australia, but now also sailing the world with his family, is thoughtful and kind. Nisha, who is vacationing on her dad’s megayacht and is bold and beautiful.

Now Mia has to decide to stay with her family or to go live with her Uncle in Tennessee.

I really enjoyed the writing and exploration of not only mental health with Mia’s mother and her OCD, but also Mia’s neurodivergence. To me, it was quite obvious that Mia was high(er) functioning autistic and I wish it was discussed or talked about more in the novel so readers could feel a bit more seen while reading. I think because of this, I was also reading Mia as younger than sixteen and felt more like she was thirteen/fourteen.

But, overall, I really enjoyed this novel. The relationships felt authentic as well as the exploration of sexuality. Things felt evenly paced and realistic time wise. Oh - and there’s amazing representation of women in STEM. I think both teen and adult readers could enjoy this novel.

*Thank you Penguin Workshop and NetGalley for a digital copy of this book in exchange for an honest review

I really enjoyed this thoughtful and beautifully written novel, which explores neurodivergence, mental health, and the messy, tender terrain of adolescence. Mia is a compelling narrator—deeply misunderstood, technically brilliant, and navigating the fallout of a friendship rupture and a forced, drifting life at sea. While I often wasn’t sure where the story was heading, it kept my attention throughout, and I especially appreciated the nuanced relationships with her new friends, which felt refreshingly real. The story seems to clearly reflect low-support-needs autism in girls, and I do wish the authors had named that diagnosis explicitly—it felt like a missed opportunity for connection and clarity. Still, this is a strong YA read that smartly portrays social awkwardness, self-discovery, and the power of finding people who truly get you. Also: more girls in science, please!

I actually enjoyed this book. I often didn’t know where it was leading yet I was still feeling like I had to keep reading. My one and only complaint is I would have loved if it wrapped up more. And we had an ending where diagnosis was talked about. But maybe that’s a part of the appeal, we’ll never really know. Overall still really liked it though!

Good book that kept my attention. The writing is beautiful and descriptive. It is not the type of book I would usually pick up.

I was hooked from the beginning!!
It was amazing and engaging.
I was instantly sucked in by the atmosphere and writing style.
The characters were all very well developed .
The writing is exceptional and I was hooked after the first sentence.

Mia has never really understood how to act in social situations, but fortunately, her friend Sadie was there to coach her on ... well, how to hide some of her weirdness. Her weirdness being: Mia was always more interested in tech stuff, such as building solar panels, than in looking fashionable or following pop culture trends. Then, something happened in their friendship: Mia had a major meltdown at school and was quietly told not to return to class the following semester. Mia's parents took their derelict boat, left their lives in Minnesota, and went sailing from island to island in the Caribbean full-time. A dream life, some might say -but Mia feels deeply misunderstood and virtually kidnapped. She secretly works on building a satellite radio to try to call Sadie. And then, after months at sea without meeting anyone her age, she makes two new friends who would push her to discover new things about herself.

This was a pretty good exploration of neurodivergence and mental health struggles (Mia's mother), as well as universal adolescent themes of fitting in versus finding a group of people who will appreciate you for who you are. To me, Mia seemed quite obviously to be a low-support-needs autistic person, to the extent that the story seemed well-informed by how level-one ASD manifests in girls. I'm still wondering why the authors decided not to overtly identify her as autistic, missing the chance to give readers who find Mia's struggles relatable a valuable hint to look into this diagnosis.

It should be said that it's not easy to please me when it comes to how interactions between teens are portrayed in YA literature, so it means something that I quite liked how Mia's relationships with Alby and Nisha unfolded. Without giving too much away, there was this raw and genuine exploration of adolescent sexuality, as well as scenes reminiscent of best of Wilde's plays (you know, the ones where a character doesn't know who is secretly present in another room and then must adjust the truths they tell different people).

And, of course, hooray for the representation of women in science!

Publication date June 3, 2025.

Thanks to the publisher for providing me with an eARC through NetGalley. The opinion above is my own.

Thank you to PENGUIN GROUP Penguin Young Readers Group | Penguin Workshop and NetGalley for an electronic advanced readers copy of this novel.

Mia is sailing with her family, sort of aimlessly because her family is adrift in more ways than one. Her mother is a germaphobe unmoored by the pandemic and wants to keep her family safe. Mia threw food after a betrayal by her best friend. Isolated, Mia talks to her imaginary friend and works on her science projects.

Mia finally runs into people her age but it just leads to more confusion.

The Uncertainty Principle is an interesting tale of a troubled teenager trying to grow up in an unusual situation. I thought it was pretty well written but I had trouble relating.

The book delves into the lives of two characters as they navigate a world where the boundaries of reality, time, and space are stretched beyond conventional understanding.

Pretty good story! I wish poor Mia had learned that she didn’t have to change herself for anyone sooner, but it was a very good book. Alby and Nisha rounded out the book and Mia’s family also added to the tale. You should read this book!