My Favorite Bit: SL Huang talks about ROOT OF UNITY

My Favorite Bit iconSL Huang is joining us today with her novel Root of Unity. Here’s the publisher’s description:

Back for book three . . .

Cas Russell has always used her superpowered mathematical skills to dodge snipers or take down enemies. Oh, yeah, and make as much money as possible on whatever unsavory gigs people will hire her for. But then one of her few friends asks a favor: help him track down a stolen math proof. One that, in the wrong hands, could crumble encryption protocols worldwide and utterly collapse global commerce.

Cas is immediately ducking car bombs and men with AKs — this is the type of math people are willing to kill for, and the U.S. government wants it as much as the bad guys do. But all that pales compared to what Cas learns from delving into the proof. Because the more she works on the case, the more she realizes something is very, very wrong . . . with her.

For the first time, Cas questions her own bizarre mathematical abilities. How far they reach. How they tie into the pieces of herself that are broken — or missing.

How the new proof might knit her brain back together . . . while making her more powerful than she’s ever imagined.

Desperate to fix her fractured self, Cas dives into the tangled layers of higher mathematics, frantic for numerical power that might not even be possible — and willing to do anything, betray anyone, to get it.

What’s SL’s favorite bit?


Women of color are rare in SFF. Older women are rare. Friendships between women are all too rare.

So it delights me greatly that at the heart of Root of Unity is the friendship between two older women of color.

Oh, and did I mention they’re both brilliant mathematicians?

I love these two characters so much. And there’s so much to their friendship that didn’t make it onto the page.

When the book begins, Sonya Halliday is in her forties and Rita Martinez is in her seventies. They’re described as formerly a mentor and student who have, in the intervening years, become collaborators and friends.

There’s more to it than that, in my mind.

Halliday is a mathematical genius, and she’s also an African-American woman. The slighting she received in the math world twenty years ago, when she was earning her degrees, would have been enough to put off the most determined mind. But she dug in her fingernails, and the harder people tried to push her out, the more stubborn she became.

Still, she might have flipped off all of academia and gone to make a fortune in finance if it hadn’t been for Martinez.

Martinez says at one point that she mentored Halliday because she saw so much of herself in her. If Halliday faced barriers entering mathematics, Martinez, a Native woman, entered the field when it was a thousand times more backward. And on a deep personal level, she’s always felt a bit like a cultural outsider in her own life. She’s had to find her own place in the world, and it hasn’t always been easy.

She persevered, and eventually did find that place: an unstable equilibrium of relative peace.

But she’s always been all too aware of the small slights and hurdles thrown in the path of her and others like her, ones that continue to this day. She wanted to mentor Halliday first because Halliday’s mind was incredible, but second because Martinez was afraid that brilliance would go unrecognized. Well, shoot, she thought — I’ll recognize it.

So she did.

But neither of them could have predicted how much that relationship would grow, and how deep their friendship would become. Halliday was so inspired by Martinez’s mentorship that she went into the same subfield, and they’ve collaborated with each other ever since, ever finding their methods and interests effortlessly compatible. Always finding their shared love of mathematics was only the beginning of what they valued in each other. After so many decades, they more than care for each other: they have each others’ backs, always and forever.

Martinez says at one point that her love for Halliday is not well defined but is “applicable by hypothesis,” and my main character later refers to the friendship between the two as Martinez’s zeroth axiom. For in their eyes, there’s no world in which their loyalty to each other isn’t knitted into the fabric of reality.

Thus, within this book of car chases and gun fights and explosion after explosion, I find myself saying “my favorite bit” is about a quiet friendship between two secondary characters.



Amazon UK



Barnes & Noble


SL Huang justifies her MIT degree by using it to write eccentric mathematical superhero fiction, starting with her debut novel, Zero Sum Game. In real life, you can usually find her hanging upside down from the ceiling or stabbing people with swords. Online, she’s unhealthily opinionated at or on Twitter as @sl_huang.

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