The discovery of quantum mechanics fundamentally changed how we understand the natural world. In 1981, physicist Richard Feynman famously observed that because nature is quantum, we would eventually need to build computers that operate on those same principles to truly understand it. Building these computers remains one of the greatest engineering challenges of our era.
At Google Quantum AI, our mission is to develop quantum computing for these complex, currently unsolvable problems. We believe large-scale, error-corrected quantum computers will be the key to unlocking certain solutions for real-world problems — from discovering more sustainable materials to accelerating drug discovery — that are beyond the reach of classical computers today.
Our focus remains on the long-term journey: moving from experimental physics to the reliable, stable systems necessary to provide these breakthroughs for everyone.
Visualizing the state of the qubit
Today’s Google Doodle marks World Quantum Day by incorporating the Bloch Sphere into our logo. In quantum mechanics, the Bloch Sphere is a geometric representation of the state space of a two-level quantum system, or qubit.
Unlike a classical bit, which is restricted to a binary state of 0 or 1, a qubit can exist in a combination of both. This is represented as a point on the Bloch Sphere, allowing for a much larger computational state space than traditional computing.
A major hurdle today is maintaining these delicate states. Interaction with the environment causes “decoherence,” where quantum information is lost to noise. Our current work is centered on building systems that can protect this information long enough to perform meaningful computations.
Answering your top-trending questions
Why do we need quantum computers? How do they reach the right answers so quickly? And what does that have to do with interference?
We sat down with Google Quantum AI experts Jenna and Andrew to tackle the world’s most-searched questions about quantum computing.

