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Quantum Time

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Jack and Sarah, sibling spies for Quotient—a global independent spy agency—are back. When a mysterious wind of death threatens President O’Connor and other world leaders, vacation is over, and the mission begins. Even their quantum computer won’t be enough to save them this time.

Jumping between two different timelines, the near future of 2028 and the far future of 2050, the team must save both today and tomorrow as the entangled missions stretch them to the breaking point.

Quantum Time blends a fast-paced adventure thriller with richly detailed locations, a large cast of engaging characters, and tomorrow’s technology. With its breakneck pace, this is one read you won’t want to miss.

Audible Audio

Published May 22, 2025

2 people are currently reading
2 people want to read

About the author

Gregory R. Simpson

5 books5 followers
Greg was CTO for one of the world's largest companies and headed the AI initiative for a Fortune 200 Financial Services firm. He has channeled his technology and global travel experiences into "The Quantum Contingent". Read more at his website at
www.simpsong00.com

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Displaying 1 - 4 of 4 reviews
Profile Image for Frank Bonfiglio.
42 reviews2 followers
June 15, 2025
I loved the writing style of this book so much. The short chapters and reality-altering technologies keep it exciting and fast-paced. I cherished the characters from Simpson’s first novel who returned in this—but was fascinated by the new ones who emerged as well. It is a book that made me think about the future of our planet during a time where that thought seems to be as timely as ever.
Profile Image for Bridget.
Author 1 book10 followers
June 26, 2025
Simpson packs more action into this sequel than most authors do in a whole series! I especially recommend the audio book for this installment, narrated by the author himself.
Profile Image for Gregory Simpson.
Author 5 books5 followers
May 5, 2025
This is my second book... Jack and Sarah are back. I hope you enjoy reading it as much as I enjoyed writing it!
2 reviews
November 27, 2025
Jack and Sarah are back! “Quantum Time" follows Jack and Sarah through time and space. Simpson explains complicated ideas like quantum physics, time travel and parallel universes in a fun way that's easy to understand.
Displaying 1 - 4 of 4 reviews

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