- Scientists are developing experiments to test whether gravity is quantum
- In quantum mechanics, which describes the behavior of atoms and molecules, objects behave differently from everything we know. An object can be in a state of quantum superposition in which it exists in two places at the same time.
- Scientists are currently investigating ways to determine whether gravity acts in this way by suspending microdiamonds in a vacuum.
- If gravity were quantum, diamonds would be “entangled.” This is an interesting phenomenon in which he strongly connects two objects in a way that is not possible in everyday life.
- This research helps advance our understanding of black holes. big bangand the universe
quantum gravity experiment
Scientists are developing experiments to test whether gravity is quantum, one of the deepest questions about the universe.
General relativity and quantum mechanics are the most basic descriptions of nature that we have. General relativity explains gravity on a large scale, and quantum mechanics explains the behavior of atoms and molecules.
Challenge to unify theory
Perhaps the most important open question in fundamental physics is determining the correct way to integrate these two theories: whether gravity operates at the quantum level. Although theoretical studies have proposed many possibilities, experiments are needed to fully understand the behavior of gravity.
Innovative experiments from a global consortium
For 100 years, experiments on the quantum properties of gravity seemed out of reach, but now researchers at the University of Warwick, UCL University, Yale University (USA), Northwestern University (USA), Groningen University ( Scientists based in the Netherlands will work together to investigate this challenge. .
Their new idea is to suspend two microdiamonds in a vacuum, placing each in a quantum superposition where they exist in two places at the same time. This counterintuitive behavior is a fundamental feature of quantum mechanics.
Insights into Professor Morley’s experiments
Each diamond can be thought of as a miniature version of Schrödinger’s cat.Principal Investigator Professor Gavin Morley, Department of Physics University of Warwick“Schrödinger’s Cat is a thought experiment that points out that it would be very strange if we could have a quantum superposition of everyday objects (and pets!) being in two places at the same time. We want to test the limits of.
“We’ve succeeded in putting atoms and molecules into such a superposition, but we want to do it with even larger objects. Our diamond is made up of more than a billion atoms. To test the quantum nature of gravity, look for interactions between two diamonds due to gravity.
“If gravity were quantum, it would be possible to entangle two diamonds. Entanglement is a unique quantum effect that binds two things together more strongly than is possible in everyday life. For example, if two coins If there is a possibility of entanglement, you may find that each time you flip them they both land in the same direction, even though it is impossible to know in advance whether they will both be heads or both tails. .”
Challenges and impacts
There are still many challenges to realizing this idea, which the team plans to explore during the project. “For example, we need to eliminate all interactions between nanoparticles other than gravity, which is very difficult because gravity is so weak,” says Dr. David Moore. yale university.
Professor Morley, founding director of Warwick Quantum, a new interdisciplinary initiative in quantum technology research, added: “For me, the most important problem in physics today is developing experiments that can test the quantum properties of gravity. This new project accelerates our exciting journey towards this. .
Perspective from a co-researcher
Professor Sougat Bose from UCL said: “It cannot be overstated how important it is for physicists to have experiments that allow us to explore the right way to combine quantum mechanics and general relativity.” People working on theories of quantum gravity such as Quantum Gravity Theory typically focus on what happens at high energies, near black holes, and in the Big Bang.
“In contrast, our research is conducted here on Earth in a lower-energy region, but it also whether Gravity is quantum. This experiment can also be seen as a validation of the general predictions of the quantum theory of gravity at low energies. ”
Professor Anupam Mazumdar from the University of Groningen said: “In the process of understanding the quantum nature of gravity, we may be able to test other aspects of fundamental physics, such as exotic deviations from Newtonian gravity over short distances.” added.
“This is a challenging experiment, and this project finds a way to address some of the key technical challenges to make testing the quantum aspects of gravity a reality,” said Associate Professor of Physics says Andrew Geraci. northwestern university.
The project is called “MAST-QG: Macroscopic superposition for witnessing the quantum nature of gravity.”