Yi Wang on Understanding Gravity on Cosmological Scales
Fast Breaking Paper Commentary, December 2010
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Article: Quantum UV/IR relations and holographic dark energy from entropic force Authors: Li, M;Wang, Y Journal: PHYS LETT B Volume: 687, Issue: 2-3, Page: 243-247, Year: APR 12 2010 * McGill Univ, Dept Phys, 3600 Univ St, Montreal, PQ H3A 2T8, Canada. * McGill Univ, Dept Phys, Montreal, PQ H3A 2T8, Canada. * Chinese Acad Sci, Kavli Inst Theoret Phys China, Key Lab Frontiers Theoret Phys, Inst Theoret Phys, Beijing 100190, Peoples R China. (Addresses have been truncated) |
Yi Wang talks with ScienceWatch.com and answers a few questions about this month's Fast Breaking Paper paper in the field of Physics.
Why do you think your paper is highly
cited?
Cosmology is a promising arena for testing new ideas in quantum gravity. We related the recently proposed entropic force conjecture to the late time acceleration of our universe (to be explained in detail below). A large number of other papers came out later describing related ideas. Our application also inspired a number of future works. These make the present paper highly cited.
Does it describe a new discovery, methodology, or
synthesis of knowledge?
Our work describes a new synthesis of knowledge. We applied the entropic force conjecture to cosmology and found the conjecture related to holographic dark energy.
Would you summarize the significance of your paper
in layman's terms?
It was conjectured recently by Verlinde that gravity is an entropic force. By entropic force one means that the microscopic origin of gravity is the second law of thermal dynamics—the increasing entropy. This conjecture opened a new window for investigating the nature of gravity.
In our paper, Prof. Miao Li and I considered the cosmological implications of this conjecture. We provided a connection between the entropic force and late time acceleration of our universe (dark energy), which is another great myth in theoretical physics.
"Presently, the entropic force conjecture has not been precise enough to make very concrete predictions."
We found that the entropic force picture can reproduce holographic dark energy, which is a previously well-known dark energy scenario. The key observation is that, to treat different holographic screens self-consistently, a quantum relation between short distance (UV) physics and long distance (IR) physics arises. This observation reproduces two conjectured UV/IR relations in quantum gravity, which lead to a holographic explanation of dark energy.
As another method, we also used another more direct way to derive holographic dark energy from Verlinde's conjecture. The result is consistent with the method from UV/IR relations.
How did you become involved in this research, and
how would you describe the particular challenges, setbacks, and
successes that you've encountered along the way?
Prof. Miao Li has a blog (in Chinese) discussing theoretical physics and other aspects in his life. From his blog I noticed the rumor of Verlinde's work even before Verlinde's paper was publicly available. After Verlinde's paper came out, I quickly become interested in the idea and wrote to Miao for possible collaboration. And you have seen the result: after a large number of pleasant and favorable email discussions, we found that Verlinde's conjecture is related to holographic dark energy.
Where do you see your research leading in the
future?
Presently, the entropic force conjecture has not been precise enough to make very concrete predictions. We are interested in seeking for precise treatment of entropic force and see whether the idea can be tested in experiments in the near future, especially in cosmology.
Do you foresee any social or political
implications for your research?
We can feel gravity in our everyday life. If the entropic force conjecture turns out to be correct, it will provide a completely new understanding of gravity. Our research goes along this way and might help people in understanding gravity on cosmological scales.
However, as the work is completely theoretical, we do not see any political
implications for our work.
Yi Wang
Physics Department
McGill University
Montreal, Canada
KEYWORDS: ENTROPIC FORCE; DARK ENERGY; HOLOGRAPHY; BLACK-HOLES.