Quantum Computers Will Challenge Gravity ⚡ экспресс
General relativity and quantum mechanics are incompatible at the Planck scale. This hypothesis could be tested if a quantum computer surpasses the classical limit of one operation per Planck volume-time, which is equivalent to 2^491 m^{-3} s^{-1}. The study establishes a quantitative relationship between the number of logical qubits and the degree to which classicality is challenged. It shows that 500 logical qubits suffice to refute theories limited to laboratory conditions. Computational and communication costs across all scales up to the observable universe are accounted for; the ultimate limit turns out to be a quantum computer with 1600 logical qubits. Remarkably, current plans for commercial quantum computers anticipate exceeding this limit, making the quantum gravity confrontation experimentally testable.
The biggest puzzle in physics is how to reconcile spacetime curvature with quantum mechanics. At the Planck length, billions of billions times smaller than an atom, the rules break down. This frontier was discovered by Max Planck.
Information flows through spacetime like water through a sponge. In the ordinary world, a sponge absorbs at its maximum rate. Similarly, there’s a classical limit to data processing—2⁴⁹¹ operations per second per cubic meter. That number is so huge it exceeds the number of atoms in the entire observable universe. No ordinary computer can break that barrier.
But a quantum computer can “absorb” information faster. If it outpaces this natural tempo, we’ll glimpse quantum gravity—the theory unifying gravity with the microscopic world. A lab test needs just 500 logical qubits—error-protected quantum cells. The absolute limit for the whole universe is only 1,600 logical qubits. This estimate echoes Jacob Bekenstein's work on black holes. Amazingly, commercial quantum computer roadmaps promise to hit 1,600 qubits within just a few years. John Preskill predicted that quantum machines would test fundamental physics. It seems that moment is almost here.
🎯 The number 2⁴⁹¹ is so large that if every atom in the observable universe were computing at the speed of light, their combined output still wouldn’t reach this limit.
🎬 The idea of computations that peel back the foundations of reality feels like science fiction—for example, Greg Egan’s novel "Diaspora".