The Thunder of Engines (#2 in The Stasis Stories)

This hard Sci-Fi novel is the second book in the “Stasis Stories,” a series of tales from the near future. They tell us about Kaem Seba, a sickly and financially destitute young man with extraordinary math talents. He’s developed a theory and an electronic device that allows him to stop time within limited volumes of space-time.
In this story, Kaem and Arya are trying to sell “stade,” which is what they call a piece of space-time that’s in stasis. Stade has phenomenal mechanical properties because it essentially can’t be altered (time’s stopped within it). It’s stronger than any known substance because, unlike matter, stade cannot melt, burn, bend, or break. It’s also a perfect insulator and reflects all radiation.
Though it’s the perfect material for thousands of different purposes, they’ve initially focused on selling it to companies that can use it to build rocket engines. Stade truly shines under the extreme conditions of rocketry, and that renders it precious. He and Arya are struggling to negotiate the best prices they can, while simultaneously fighting another company’s bid to preempt their patent.
As if those struggles weren’t sufficient, Kaem’s beloved father develops cancer. Kaem must try to help his family through that crisis while simultaneously attempting to save the new company they’re calling “Staze.”