In 1995 I obtained my PhD from Leiden Observatory (Cum Laude). I have worked at the Johns Hopkins University and at Harvard University before becoming a full professor at the Kapteyn Astronomical Institute (University of Groningen). In my theoretical work I study black holes, dark energy, the formation of stars and planets, primordial and active galaxies, space-time topology and particle physics.

Quantum Space-Time

For a layman introduction to my quantum space-time theory of ``topological dynamics'', click here . Below is a visual impression of travel by identification of distinct space-time locations. The red and blue ball are the same, their color simply indicates how the edges of the square are identified to form the surface of a donut in three dimensions. In four dimensions, one can do this with a solid cube to get a three-torus. A lattice is constructed by gluing many such three-tori together.

Specifically, in 1996 (see paper 1 below) I proposed a lattice of three-tori in four dimensions as the topology of Planckian space-time. Such a lattice of three-tori allows for a natural implementation of the Heisenberg uncertainty principle, through the Feynman path integral, because it imposes different paths between space-time points. In fact, for any universe with a finite measuring accuracy, one must have a lattice of three-tori and therefore quantum mechanics. Furthermore, one may naturally attach wormholes (black holes) to such a lattice of three-tori, and thus include gravity. This leads to a cosmological ''constant'' term in the Einstein equation that is proportional to the number of macroscopic black holes in the universe. Paper 1 predicted that the global expansion of space-time accelerates as more and more black holes are formed through cosmic time. This is precisely what one needs in order to explain the currently popular notion of dark energy.

Paper 1: read here how the number of black holes determines the cosmological ''constant''.

Paper 2: read here how space-time topology determines particle physics.

Paper 3: read here how Einstein gravity can be derived from space-time topology.

Paper 4: read here how Einstein's elevator/rocket experiment requires information.

Paper 5: read here how quantum measurement information affects general relativity.

Paper 6: read here how space-time topology causes the LHC to leak, e.g., Higgs particles.

Paper 7: read here how the connection between dark energy and black holes can be tested.