Scientists from the Universities of Warwick, UCL, Yale, Northwestern, and Groningen are developing an experiment to test if gravity operates on a quantum level. The project, named ‘MAST-QG: Macroscopic superpositions towards witnessing the quantum nature of gravity’, involves levitating micro diamonds in a vacuum to observe if they exhibit quantum superposition – being in two places at once. If gravity is quantum, it will ‘entangle’ the diamonds, a phenomenon linking two objects in ways impossible in everyday life. This research could enhance our understanding of black holes, the Big Bang, and the universe.
Quantum Gravity: A New Frontier in Physics
The two most fundamental descriptions of nature are general relativity, which explains gravity on large scales, and quantum mechanics, which describes the behavior of atoms and molecules. The challenge is to reconcile these two theories.
The Experiment: Levitating Micro Diamonds
The team, comprising scientists from the Universities of Warwick, UCL, Yale, Northwestern, and Groningen, plans to levitate two microdiamonds in a vacuum and put each into a quantum superposition of being in two places at the same time. This counterintuitive behavior is a fundamental feature of quantum mechanics. Each diamond can be thought of as a smaller version of Schrödinger’s cat, a thought experiment that illustrates the concept of quantum superposition.
The Role of Entanglement in Quantum Gravity
If gravity is quantum, it would be able to entangle the two diamonds. Entanglement is a unique quantum effect where two things are linked more strongly than is possible in our everyday life. For example, if two coins could be entangled then you might find that whenever you flip them, they both land the same way up even if it’s impossible to know in advance if they will both be heads or both tails.
Challenges and Implications of the Experiment
There are still many challenges to realizing this idea, which the team will investigate during the project. For example, all interactions between the nanoparticles besides gravity must be eliminated, which is incredibly challenging since gravity is so weak. However, the implications of this experiment are significant. It could provide invaluable information about whether gravity is quantum and verify a generic prediction of any quantum theory of gravity at low energies.
The Broader Impact on Physics
The experiment could also test other aspects of fundamental physics such as exotic deviations from Newtonian gravity at short distances. This project is a pathfinder to address some of the key technical challenges to make these tests of quantum aspects of gravity a reality. The project is called ‘MAST-QG: Macroscopic superpositions towards witnessing the quantum nature of gravity’.
The Team Behind the Experiment
The team includes Principal Investigator Professor Gavin Morley from the Department of Physics, University of Warwick, Dr David Moore from Yale University, Professor Sougato Bose from UCL, Professor Anupam Mazumdar from the University of Groningen, and Andrew Geraci, Associate Professor of Physics, Northwestern University. Professor Morley is also the founding director of Warwick Quantum, a new interdisciplinary initiative for Quantum Technology research.
The Future of Quantum Gravity Research
The research into quantum gravity is an exciting journey towards understanding the deepest questions about our universe. It could help drive understanding of black holes, the big bang, and the universe. The experiment is a significant step towards answering whether gravity is quantum, and the results could have profound implications for our understanding of the universe.
“Schrödinger’s cat is a thought experiment pointing out that it would be really weird if everyday objects (and pets!) could be in a quantum superposition of being in two places at once. We want to test the limits of this idea. Atoms and molecules have been successfully put into such a superposition state, but we want to do this with much larger objects. Our diamonds are made up of one billion atoms or more. To test the quantum nature of gravity, we would look for interactions between two such diamonds due to gravity. If gravity is quantum, then it would be able to entangle the two diamonds. Entanglement is a unique quantum effect where two things are linked more strongly than is possible in our everyday life. For example, if two coins could be entangled then you might find that whenever you flip them, they both land the same way up even if it’s impossible to know in advance if they will both be heads or both tails.” – Professor Gavin Morley, Department of Physics, University of Warwick
“For me, the most important problem in physics right now is to develop an experiment that can test the quantum nature of gravity. This new project is an acceleration in our exciting journey towards this.” – Professor Gavin Morley, Department of Physics, University of Warwick
“It is hard to overstate how significant it would be for physicists to have experiments that could probe the correct way to combine quantum mechanics and general relativity. People working on theories of quantum gravity such as string theory typically focus on what’s happening at high energies, near black holes and at the big bang. In contrast, our work is in the low-energy regime right here on Earth, but it would also provide invaluable information about whether gravity is quantum. Also the experiment can be regarded as the verification of a generic prediction of any quantum theory of gravity at low energies.” – Professor Sougato Bose, UCL
“On the way to understanding the quantum nature of gravity, we may be able to test other aspects of fundamental physics such as exotic deviations from Newtonian gravity as short distances.” – Professor Anupam Mazumdar, University of Groningen
“This is a challenging experiment, and this project is a pathfinder to address some of the key technical challenges to make these tests of quantum aspects of gravity a reality” – Andrew Geraci, Associate Professor of Physics, Northwestern University
Summary
Scientists are developing an experiment to test if gravity operates on a quantum level, a question fundamental to our understanding of the universe. The experiment involves levitating micro diamonds in a vacuum, with the theory that if gravity is quantum, it will ‘entangle’ the diamonds, a phenomenon linking two objects in ways impossible in everyday life.
- Scientists from the Universities of Warwick, UCL, Yale, Northwestern, and Groningen are developing an experiment to test whether gravity operates on a quantum level.
- The experiment involves levitating two microdiamonds in a vacuum and putting each into a quantum superposition of being in two places at the same time.
- If gravity is quantum, it would be able to ‘entangle’ the two diamonds, a unique quantum effect where two things are linked more strongly than is possible in everyday life.
- This research could help drive understanding of black holes, the big bang, and the universe.
- The project is called ‘MAST-QG: Macroscopic superpositions towards witnessing the quantum nature of gravity’.
- Principal Investigator Professor Gavin Morley, Department of Physics, University of Warwick, and Dr David Moore, of Yale University, are among the key individuals involved in the project.
- The team acknowledges that there are many challenges to realizing this idea, including the need to eliminate all interactions between the nanoparticles other than gravity.