FIFTH FORCE TP (9781955537377)

Earth is on the verge of extinction. We have limited crude oil and our primary fuel sources are negligible. The carbon clouds signal the end of our species. We have but a few options: leave the planet… or fix it.
We are the TFA, a special Canada-based agency that stumbled across a revolutionary discovery. The fifth Elemental force. Time.
We built a freaking time machine based on the new physical sciences, believing we can go back to the 'inflection points' of this extinction level event and fix things.
The irony here is that the fuel we need to operate the invention, is the very fuel that led us to this juncture.
Even with the precautions in place we only have enough for a limited number of time jumps, 5 to be exact.
To make things even more difficult, time travel has a few additional 'restrictions' as the discovery of time as a fundamental force provides a Quantum and Physical science sandbox. This means that the tachyons that interact with matter do so similarly to protons and neutrons, they cannot engage in something that would create a paradox.
In layman's terms, they prohibit certain interactions between those from the future and those in the present.
I'm Doctor Malik Fikai, one of the three Inflectors tasked with going back and fixing this mess before it happens, otherwise our future is history.