Researchers from China and Hong Kong have developed a new method of checking the properties of quantum computers, allowing for interchangeable input and output ports. This groundbreaking method, based on a “quantum coup of time,” confirms that in certain quantum systems, time can be reversible.
In everyday life, time only moves forward, leading to many irreversible processes. This phenomenon, known as the “arrow of time,” is a result of the universe’s expansion since the Big Bang. However, in quantum mechanics, processes that can change the direction of time are possible at the nano level, as confirmed by the CPT theorem (Charge, Parity, and Time Reversal Symmetry).
A recently published research in the journal Physical Review Letters demonstrates that time can be converted in quantum systems by creating a double superposition in opposite directions. This results in uncertain input and output data, making them interchangeable.
On quantum computers, inputs and outputs are represented by entangled qubits or other particles in a state of superposition. These microscopic particles work together to convey information, similar to how traditional computers use a binary system.
The novelty of this study lies not only in the concept of reversible input and output ports but also in the development of a method to verify the accuracy of these systems. Scientists have devised a virtual model of a device known as a “quantum coup of time,” which manipulates light both forward and backward in time using a single photon.
Researchers suggest that this type of uncertainty, where inputs and outputs can be interchangeable, could play a crucial role in developing a unified theory of quantum gravity. While a definitive physical model for such scenarios has not yet been proposed, having a mathematical foundation and an experimental platform for their exploration is a valuable asset for understanding their potential implications.