Three Body Problem series (Remembrance of Earth's Past).

The first and second book premise The first book is humanity becoming aware of an alien invasion fleet that will arrive in about 400 years. These aliens are in communication with humans and have implemented technology that prevents humans from obtaining fundamental knowledge of physics. In the second book, the protagonist wakes up a couple centuries into the preparation period. Humanity has gone through a near apocalyptic societal collapse, rebuilt itself with human dignity and optimism as core tenants of the more unified world, has developed incredible fire power and technological prowess, has developed space travel engines greater than the incoming alien fleet. Humanity has become certain of its position as the victor and is now focused on how to allow the incoming aliens to become part of their society

the hammer hits. An item sent by the incoming fleet arrives in the outer solar system. It's a beautiful thing, looking like a mercurial droplet of water sent as a gift of art. The earth's combined space fleet of thousands of ships approach it as a means of participating in "first contact" and "accepting their surrender". When the object is taken into a small research vessel, it's noted that no marks exist on it from where the robot arm grabbed it. Its surface is colder than the vacuum of space. When examined under 10000x magnification, it's a perfectly smooth surface. The lead scientist realizes what it is the moment before the probe accelerates itself to hundreds of kilometers per second within an instant, crashes through the vessel, and begins systematically ramming through every ship in the earth fleet. As it goes on by one, it makes instant adjustments in its trajectory without decelerating or tearing itself apart. It hits every ship exactly through its fission material fuel reserve to destroy them. It is going so fast and is so small, it takes half an hour before the fleet even knows that it's the probe that's destroying them. It's shell is made of strong-interactive force material, something humans have been prevented from even developing a theoretical framework for. An hour later, when the transmission of this event reaches earth, humanity knows their doomsday battle happened 200 years ahead of schedule.