This conference, held on 22-26 September 2008 in Mainz, covers the work performed in the 20th century after Einstein published his theory of General Relativity. Topics include geometry, gravitational waves, cosmology and more.

The conference consists of 27 lectures, divided into themes of 3 lectures each. These are as follows:

**General Relativity: Geometry and Unification**, on the geometrical description of gravity, and the aims to unify the gravitational force with the other fundamental forces.

*Do we live in a “small” universe?*

*Mathematicians, Einstein and the Unification Project: a tale of two cities*

*Unified Field Theory up to the 1960s: its development and the interaction between research groups*

**Formative Ideas for Spacetime Structures**, on the discovery of spacetime by Minkowski, and Lorentz contraction and time dilation.

*Why do rods contract? Extending Bell’s “Lorentzian Pedagogy” into General Relativity*

*How did Minkowski discover spacetime?*

*What is General Relativity?*

**Relativity in Göttingen and Beyond**, on the interaction between Einstein and Hilbert.

*General Relativity from Hilbert’s perspective*

*Hilbert and Einstein’s General Theory of Relativity: 2 communications on the Foundations of Physics*

*From the Schwarzschild Singularity to the Black Hole Horizon*

**Testing General Relativity and Rival Theories**, on experiments to test predictions made by General Relativity and rivaling theories.

*Putting GR to the test: 20th century highlights and 21st century prospects*

*Rotating Hollow and Full Spheres: Einstein, Thirring, Lense and beyond*

*The Rise and Fall of the Fifth Force*

**Cycles, Waves and Inflation**, on cyclic cosmology, gravitational waves and inflation theory.

*Continual Fascination: Oscillatory Cosmological Models after Einstein*

*Relativistic Lighthouses: The role of Binary Pulsars in proving the Existence of Gravitational Waves*

*Inflation as a theory of Structure Formation*

**Conformal Boundaries and Quantum Geometry**, on the application of conformal field theories to GR and geometry.

*Classical Singularities and Quantum Spacetime*

*Development and Applications of Conformal Infinity*

*Conformal Boundaries, Quantum Geometry and Cyclic Cosmology*

**Mainstream and Exotic Cosmology**, on modified theories of gravity and vacuum energy.

*Problems with Modified Theories of Gravity as Alternatives to Dark Energy*

*Cosmologies with Cosmic Vacuum Energy Decay and the Creation of Effective Cosmic Matter*

*Can scale covariant Weylian Geometry be relevant to Contemporary Cosmology?*

**Mathematical Motifs in General Relativity**, on mathematical methods and theories such as the Cauchy problem and the Poincaré conjecture and their role in General Relativity.

*On Cosmic Censorship and the Cauchy problem*

*The Unexpected Resolution of the Poincare Conjecture*

*On the Nature of Geometrodynamics*

**Quantum Gravity and String Theory**, on using Quantum Field Theory in curved spacetime and the connection between string theory and spacetime.

*On Quantum Field Theory in Curved Spacetimes*

*String Theory and Spacetime Geometry*

*Events in Quantum Theory and the Emergence of Spacetime*