Quantum Researcher Helps Show Why the Universe May Be Stuck in Place, and Why That's a Good Thing
The universe may be trapped in its own comfort zone, and a Syracuse University researcher has helped explain why it cannot seem to leave. A new study suggests the universe could be locked into its current state by the same kinds of quantum effects that scientists study when trying to preserve fragile information inside a quantum computer.
The paper, titled "Cosmic Lockdown: When Decoherence Saves the Universe from Tunneling," has been accepted for publication in the Journal of Cosmology and Astroparticle Physics. It was written by Gregory Kaplanek, a postdoctoral researcher working in the lab of Jason Pollack, an assistant professor in the Department of Electrical Engineering and Computer Science, along with four collaborators: Robson Christie and Jaewoo Joo of the University of Portsmouth in the United Kingdom, Vincent Vennin of the Laboratoire de Physique de l'Ecole Normale Superieure in France, and David Wands, also of Portsmouth. Kaplanek and Pollack are part of Syracuse University’s Institute for Quantum and Information Sciences.
The research addresses a long-standing worry among physicists: that the universe could be sitting in what is known as a false vacuum, a state that looks stable but is not actually the lowest-energy configuration available to it. Quantum mechanics allows a field to tunnel out of such a state without warning, a shift that could alter the fundamental properties of the cosmos.
That concern is not purely theoretical. Some calculations indicate the Higgs field, which helps give particles like electrons their mass, may itself be resting in a false vacuum rather than in nature's true lowest-energy state. If it ever tunneled to a deeper state, the properties of particles and forces throughout the universe could change.
The new study finds a mechanism that makes such a transition far less likely. The researchers modeled how a quantum field behaves when it interacts with its surroundings during the rapid expansion of the early universe. They found that those interactions can strongly suppress tunneling, effectively trapping the field in whatever state it has already settled into. The team calls this effect "cosmic lockdown."
The underlying physics comes from a field called open quantum systems, which studies how quantum systems change when they interact with an environment rather than existing in isolation. The same ideas are central to quantum computing, where even minor outside interference can disrupt a quantum system's behavior. The researchers combined those techniques with numerical simulations of a quantum field evolving in an expanding universe.
In simple terms, the interactions carry information about the field out into its surroundings. Once that information is effectively lost track of, interference between two possible outcomes fades in a process called decoherence. In the regime the team studied, that loss of interference can also suppress the field's ability to tunnel at all, a variation of what physicists call the quantum Zeno effect, in which persistent monitoring of a system inhibits its transitions.
The researchers describe two distinct stages in the process. Early on, as the universe expands, a field's ability to keep pace with that expansion largely determines which of two possible energy states it ends up favoring. Heavier fields tend to settle toward the lowest-energy option, while lighter fields can end up more evenly split between the two. Later, decoherence from the environment helps lock in whichever outcome already occurred.
The authors caution that the result does not prove the universe's current state will remain stable forever or determine the specific likelihood that the Higgs field will eventually decay. Confirming that would require accounting for additional factors, including a changing cosmic expansion rate and the field's own influence on gravity.
Still, the team frames the work as a bridge between quantum information science and cosmology, applying tools originally developed for quantum computers to a question about the history and long-term fate of the universe itself.