Your future internet may bend space-time, literally

By Amit Malewar Published: August 5, 2025

Collected at: https://www.techexplorist.com/quantum-physics-meets-gravity/100374/

Imagine trying to ride a rollercoaster that twists through invisible hills and valleys, except the rollercoaster is made of quantum particles, and the track is the very fabric of space and time, slightly curved like a sheet pulled tight but not flat.

Physicists have a solid blueprint of how this quantum coaster should move along curved spacetime, far beyond the comfortable territory of Newton’s laws. However, here’s the catch: nobody has built a real ride yet. We’ve never actually seen quantum behavior play out on these cosmic curves.

Why? Because the “bends” in spacetime are so minuscule over the tiny scales where quantum particles do their thing, it’s like trying to spot a pebble’s ripple in the ocean.

A new study shows that quantum networks can do more than we thought; they might even help us test how gravity (curved spacetime) affects quantum physics.

In a paper published in PRX Quantum, scientists from Stevens Institute of Technology, the University of Illinois, and Harvard created a clever experiment using a “distributed atomic clock.” This setup could be the first to test quantum theory in a curved spacetime, a feat never achieved before.

A previous study has shown that now is an ideal time to begin investigating the interaction between quantum physics and gravity, particularly through the use of quantum networks. Researchers found that two key ideas come together in this context:

In quantum physics, particles can exist in superpositions, meaning they are in multiple states simultaneously. Quantum computers utilize this concept to construct qubits that can exist in both 0 and 1 states simultaneously.

Quantum networks can share these qubits across long distances.

However, near Earth, gravity affects how time flows, depending on elevation or position. The study showed that if atomic clocks are placed in superpositions across different locations using quantum networks, they would experience different flows of time at once. This enables the direct investigation of how quantum effects and the curvature of spacetime interact.

Pikovski, Borregaard, and Covey’s team created a detailed plan to test quantum physics in curved spacetime. They demonstrated that quantum effects can be propagated across different points in a network using a special type of shared quantum state known as a W-state.

By carefully measuring how these quantum systems interfere with each other, scientists can detect subtle influences from curved spacetime.

To make this possible, they utilized modern quantum tools, including quantum teleportation, entangled Bell pairs, and atomic arrays. Together, these allow for an actual experiment to study how gravity affects quantum mechanics.

Igor Pikovski, Geoffrey S. Inman Junior Professor at Stevens Institute of Technology, and one of the authors, said, “We assume that quantum theory holds everywhere, but we don’t know if this is true. It is possible that gravity alters the way quantum mechanics operates. Some theories suggest such modifications, and quantum technology will be able to test that.”

The work of Pikovski, Covey, and Borregaard shows that quantum networks are more than just high-tech tools for tomorrow’s internet; they’re powerful instruments for exploring the deepest laws of nature.

By utilizing entangled particles and advanced quantum protocols, these networks enable scientists to investigate how quantum mechanics behaves in curved spacetime, a domain shaped by gravity and previously inaccessible to experimental testing. This kind of test can’t be performed with traditional tools; it requires the unique sensitivity and complexity that quantum systems offer.

Journal Reference

1. Jacob P. Covey, Igor Pikovski, and Johannes Borregaard. Probing Curved Spacetime with a Distributed Atomic Processor Clock. Physical Review. DOI: 10.1103/q188-b1cr