Don N. Page

Professor of Physics and CIAR Cosmology Fellow
A.B., William Jewell College
M.S. and Ph.D., California Institute of Technology

Research Interests

The goal of quantum cosmology is to try to understand the universe as a whole within the current fundamental framework of physics, quantum theory. Quantum theory normally differs significantly from classical theory only for small systems, so one may question its application to the entire universe. However, the universe was apparently once so small that a quantum description would have been essential. The present universe may be viewed as a relict of processes that occurred in its very early evolution. Thus a quantum understanding of these processes may help explain certain basic features observed today. For example, the observed cosmos is large, old, nearly flat, fairly homogeneous and isotropic at the largest observable distances, lumpy and complex on smaller scales, and out of thermal equilibrium, exhibiting a pervasive arrow of time. These basic features are mysterious, in the sense that it would apparently be consistent with our present theoretical understanding of physics for the universe not to have any of these properties. Can we enlarge our understanding to include fundamental principles that would explain these observed features of the cosmos? In particular, we need principles for the boundary conditions of the universe, to select the actual universe from the apparently infinite set of possible universes obeying the same complete set of dynamical laws. There have recently been proposals for this that would specify the quantum state of the universe, such as the Hartle-Hawking no-boundary proposal and the Vilenkin tunneling proposal. Research is being done on the implications of these and other proposals to see whether or not they can explain the observed features of our mysterious universe.

Selected Publications

  • Will Entropy Decrease if the Universe Recollapses? Don N. Page, Phys. Rev. D32, 2496-2499 (1985).
  • Operator Ordering and the Flatness of the Universe, S.W. Hawking and Don N. Page, Nucl. Phys. B264, 185-186 (1986).
  • Density Matrix of the Universe, Don N. Page, Phys. Rev. D34, 2267-2271 (1986).
  • How Probable is Inflation? S.W. Hawking and Don N. Page, Nucl. Phys. B298, 789-809 (1988).
  • Lectures on Quantum Cosmology, Don N. Page, in Gravitation: A Banff Summer Institute, eds. R. B. Mann and P. Wesson (World Scientific, Singapore, 1991), pp. 135-170.
  • Information in Black Hole Radiation, Don N. Page, Phys. Rev. Lett. 71, 3743-3746 (1993).
  • Black Hole Information, Don N. Page, in Proceedings of the 5th Canadian Conference on General Relativity and Relativistic Astrophysics, eds. R.B. Mann and R.G. McLenaghan (World Scientific, Singapore, 1994), pp. 1-41; hep-th/9305040.
  • Aspects of Quantum Cosmology, Don N. Page, to be published in Proceedings of the International School of Astrophysics "D. Chalonge," 4th Course: String Gravity and Physics at the Planck Energy Scale, Erice, Sicily, 8-19 September 1995, ed. N. Sanchez (Kluwer, Dordrecht, 1996); gr-qc/9507025.
    Don N. Page, don@phys.ualberta.ca