# Contributing Institutions

### Members of the following institutes and institutions have contributed to Einstein Online as part of their Science Outreach activities

## California Institute of Technology

## Heidelberg University

**Cosmic Sound: Curvature and the cosmic background radiation**(Matthias Bartelmann)

## Max Planck Institute for Astronomy

**Einstein’s Nobel heritage**(Markus Pössel)

**The sum over all possibilities: The path integral formulation of quantum theory**(Markus Pössel)

**The wave nature of simple gravitational waves**(Markus Pössel)

**A tale of two big bangs**(Markus Pössel)

**What figure skaters, orbiting planets and neutron stars have in common**(Markus Pössel)

**Heat that meets the eye**(Markus Pössel)

**The shape of space**(Markus Pössel)

**Changing places – space and time inside a black hole**(Markus Pössel)

**Chirping neutron stars**(Markus Pössel)

**Is the whole the sum of its parts?**(Markus Pössel)

**Mass and more**(Markus Pössel)

**The dark heart of the Milky Way**(Markus Pössel)

**The definition of “now”**(Markus Pössel)

**The elevator, the rocket, and gravity: the equivalence principle**(Markus Pössel)

**Waves, motion and frequency: the Doppler effect**(Markus Pössel)

## Max Planck Institute for Astrophysics

**Big Bang Nucleosynthesis: Cooking up the first light elements**(Achim Weiss)

**Equilibrium and Change: The physics behind Big Bang Nucleosynthesis**(Achim Weiss)

**Elements of the past: Big Bang Nucleosynthesis and observation**(Achim Weiss)

## Max Planck Institute for Gravitational Physics (AEI)

**First measurement of gravitational waves of colliding neutron stars**(Tim Dietrich)

**Extra dimensions – and how to hide them**(Stefan Theisen)

**Listening posts around the globe**(Badri Krishnan and Carsten Aulbert)

**The embedded universe**(Stefan Theisen)

**The mathematical universe**(Alan Rendall)

**Hunting for extra dimensions**(Stefan Theisen)

## Perimeter Institute for Theoretical Physics

**Actors on a changing stage: quantum gravity and background independence**(Lee Smolin)

**Geometry from order: causal sets**(Rafael Sorkin)