Exploring the mathematical nature of space-time and physical reality could pave the way for innovative computer-like systems that utilize gravity for data processing.

Is space-time an immutable expanse, or is it subject to distortion that influences the signals traversing it? While Albert Einstein’s special theory of relativity suggests stability, his general theory signifies otherwise. In this context, massive objects can create indentations and curves in space-time, altering signal trajectories, akin to a ball impacting a taut surface.

Eleftherios-Ermis Tselentis from the Brussels Institute of Technology and Ämin Baumeler of the University of Lugano in Switzerland have devised a mathematical framework to ascertain the constancy of space-time in specific regions.

They investigated a situation in which three individuals send messages amongst themselves. They posed the question: Could Alice, Bob, and Charlie discern if space-time distortions affected their information exchange? Could Alice receive a message from Bob if the spatial-temporal region through which the signal travels is altered? This might allow her to invert the causal dynamics between Charlie and Bob, thus causing Bob to influence the space-time around her prior to obtaining a reply from Charlie.

Tselentis and Baumeler formulated equations to assist Alice, Bob, and Charlie in recognizing the feasibility of these scenarios. After multiple rounds of communication, they compiled data on received messages, which was subsequently integrated into their equations.

The outcomes indicate whether their exchange occurred in an environment where space-time manipulation was viable. This mathematical construct is general enough that the participants do not need awareness of their locations or non-standard messaging tools.

Baumeler noted that while the general theory of relativity has long been a cornerstone of our understanding of physical existence, a rigorous mathematical connection between space-time fluctuations and information flow had been absent. Grasping the dynamics of information flow is foundational for computer science.

In this regard, he believes their research could initiate a nascent exploration of using gravitational effects to manipulate and navigate space-time for computational purposes.

“If one can harness the enigmas of physics for computation, why not explore the general theory of relativity?” stated Pablo Arrighi from Paris Clay University. He pointed out that while other researchers posit extreme concepts such as placing computers in black holes, space-time distortions at black hole edges slow down time, allowing for potentially extensive calculations to yield results.

Nonetheless, the new theory uniquely sidesteps a focus on specialized devices or specific aspects of space-time, allowing for a broader range of applications, according to Arrighi. However, creating “gravity-based information” systems does not appear feasible at present.

Tselentis and Baumeler also acknowledged that substantial additional research is necessary before devising a functional device. Their current calculations depend on fantastical scenarios, such as moving an entire planet to interject between Charlie and Bob. Practical applications will necessitate a deeper comprehension of gravity’s effects at much smaller scales.

Gravity is notoriously weak when it comes to smaller objects, thus one doesn’t typically perceive the impact of space-time distortions with everyday items like a pencil on a desk. Yet, certain instruments, such as clocks using ultracold atoms, can detect these phenomena. Future advancements in such devices, alongside theoretical progress linking gravity and information, could enable more applicable outcomes from Tselentis and Baumeler’s mathematical research.

Their work posits that diverse frameworks, like information theory and special relativity, can shed light on how causal relationships are perceived. V. Virasini from the University of Grenoble Alpes in France notes that the new research touches on concepts such as event order reversal, prompting inquiries into fundamental notions like events (e.g., Alice pressing a button to dispatch a message).

She suggests that the next step involves fully integrating this approach, facilitating further exploration into the essence of space-time.

“Do astrophysical events, like black hole mergers that generate gravitational waves impacting Earth, carry a meaningful signature of the correlations examined in this study?” she inquires.