Quantum Echoes Reminds Us That Algorithms Matter

Google’s October 2025 announcement of Quantum Echoes is more than just another claim of quantum advantage. It brings back into the conversation an important idea that has been forgotten over the last five years – algorithmic creativity is essential to unlocking quantum utility. For years, vendors have focused on scaling qubits and refining control stacks. Echoes shifts the spotlight back to the design of the task itself. This will influence the shape and the trajectory of quantum computing advancement  in 2025.

We said it in 2024: Progress ≠ Utility

In our State of Quantum Computing, 2024 I pointed towards progress but also called out the lack of practical usefulness, which I now call utility to disambiguated it from other confusing terms like supremacy or advantage.

• Quantum hardware improved, but business value lagged. In our State of Quantum Computing 2024, we noted that gate-modeled systems were making strides in qubit coherence and fidelity. IBM’s quality reset  in Heron and Google’s Willow chip reflected a maturing ecosystem. But we also made it clear: these gains didn’t yet translate into utility. Optimization and simulation showed promise, but business impact remained elusive.

• Quantum security took priority. The pace of progress was why we elevated Quantum Security to a top emerging technology for both 2024 and 2025. The long transition time — and the “harvest-now, decrypt-later” risk — justified urgent action. We advised clients to begin Quantum Security migration immediately, even as cryptographically relevant machines remained years away.

Echoes Is Algorithmic Progress, Not Just Better Hardware

Google’s Quantum Echoes announcement marks a pivotal moment in quantum computing’s evolution. Rather than touting raw qubit counts or control fidelity, Echoes reframes the conversation around algorithmic ingenuity. By transforming a diagnostic tool into a verifiable computational task, Google demonstrated that clever problem design — not just hardware scale — is the key to unlocking quantum advantage on the path to utility. This shift has implications for scientific discovery, enterprise strategy, and the future of quantum credibility.

• Echoes turns diagnostics into computation. Google’s Quantum Echoes algorithm repurposes the out-of-time-order correlator (OTOC), traditionally used to study quantum information scrambling, into a measurable and verifiable computational task. The higher-order variant, OTOC(2), enables cross-platform validation and sets a new benchmark for algorithmic creativity.

• Willow delivers a 13,000× speedup over classical supercomputers. Running Echoes on the Willow processor, Google achieved a runtime separation of ~13,000× compared to Frontier-class machines. This task-specific advantage goes beyond prior sampling claims and is backed by a rigorous “red-team” classical hardness analysis.

• Verifiability is built into the algorithm. Unlike typical quantum experiments that yield hard-to-verify bitstrings, Echoes produces expectation values that can be cross-checked across devices. This enhances credibility and sets a precedent for future quantum claims.

What This Means For 2025

Google’s announcement of ‘quantum advantage’ in 2025 still falls short of what most firms care about – utility. By casting advantage as yet another milestone, Google took and important step but also muddied the waters in terminology by claiming advantage without practical value delivery. Here is what to know:

• Error correction and logical qubits will continue. Momentum toward stabilized operations continues. Vendors are prioritizing quality over count, and logical qubit design is advancing. These trends will make it easier to test and deploy protocols like Echoes in real-world settings.

• Algorithmic creativity will unlock quantum utility. Google’s Echoes algorithm reframes a diagnostic tool into a verifiable computational task, signaling a shift from hardware-centric progress to problem design as the key to quantum advantage. With hundreds of quantum algorithms cataloged but few proven useful, Echoes exemplifies the kind of ingenuity needed to achieve utility. As hardware stabilizes and software stacks mature, expect breakthroughs that come not from brute force but from reframing problems to exploit quantum strengths.

• Scientific utility may precede broad value. Google connects Echoes to Hamiltonian learning and NMR-style spin echoes. The protocol could be useful for research and development in material sciences in, for example, drug discovery and materials science. But these are high expertise endeavors – quantum computers are still far from common utility computers solving problems for mainstream businesses.

The Bottom Line

Our bottom line on this announcement, quantum computing and security remains:

• Quantum Echoes is another milestone towards quantum utility. It revives algorithmic creativity, a long-neglected ingredient in quantum progress. As we head into 2025, expect more reframed tasks, better error correction, and growing pressure to secure data before Q-day arrives. The sound you hear isn’t quantum utility landing — it’s the echo of a field learning how to prove itself.

• Quantum security urgency remains. Innovations like Echoes as well as real advancements in error correction, coupled with solid vendor roadmaps to value scale computing only underscores the urgency for firms. You must be on the road to implementing post-quantum cryptography and cryptographic agility, both elements of quantum security.

Look for our State of Quantum Computing report update soon, read the State of Quantum Security, or have a guidance session with me or one of our security experts now.