In a process that could be compared to travelling through a wormhole, researchers from the Massachusetts Institute of Technology, California Institute of Technology, Harvard University, and other institutions sent quantum information across a quantum system. The Sycamore quantum processor device was used in this experiment, which pave the way for more quantum computer research into gravitational physics and string theory in the future.
Calculations from the experiment showed that qubits moved from one system of entangled particles to another in a model of gravity, even though this experiment didn’t produce a disruption of physical space and time in the sense that might understand the term “wormhole” from science fiction.
A wormhole connects two far-off regions of spacetime. Nothing is allowed to travel through the wormhole in the general theory of relativity. But in 2019, some scientists hypothesised that an entangled black hole-created wormhole might be passable.
By introducing a direct interaction between the distant spacetime regions and using a straightforward quantum dynamical system of fermions, physicists have discovered a quantum mechanism to make wormholes traversable. This type of “wormhole teleportation” was also created by researchers using entangled quantum systems, and the outcomes were confirmed using classical computers.
In this experiment, researchers used the Sycamore 53-qubit quantum processor to teleport a quantum state from one quantum system to another to send a signal “through the wormhole.” The research team had to find entangled quantum systems that behaved as predicted by quantum gravity while also being small enough to run on current-generation quantum computers.
Finding a simple enough many-body quantum system that maintains gravitational properties was a key challenge for this work. The team gradually reduced the connectivity of highly interacting quantum systems using machine learning (ML) techniques to accomplish this. Each example of a system with behaviour that is consistent with quantum gravity that emerged from this learning process only needed about 10 qubits, making it the ideal size for the Sycamore processor.
It was crucial to find such tiny examples because larger systems with hundreds of qubits would not have been able to function on the quantum platforms currently in use. The team observed the same information on the other 10-qubit quantum system on the processor after inserting a qubit into one system and sending an energy shockwave across the processor after doing so.
Depending on whether a positive or negative shockwave was applied, the team measured how much quantum information was transferred between two quantum systems. The researchers demonstrated that a causal path between the two quantum systems can be established if the wormhole is kept open for enough time by the negative energy shockwaves. It is true that the qubit that was inserted into one system also appears in the other.
The team then used conventional computer calculations to confirm these and other properties. Running a simulation on a traditional computer is not like this. A conventional simulation, which involves the manipulation of classical bits, zeros, and ones, cannot create a physical system, even though it is possible to simulate the system on a classical computer and this was done as described in this paper.
Future quantum gravity experiments could be conducted using more advanced entangled systems and larger quantum computers because of this new research. This research does not replace direct observations of quantum gravity, such as those obtained through the Laser Interferometer Gravitational-wave Observatory’s detection of gravitational waves.
