Related Concept Videos
The Principle of Superposition and the Gravitational Field
Space-Time Curvature and the General Theory of Relativity
This has been verified in many experiments. However, space and time are no longer absolute. Two observers moving relative to one another do not agree on the length of objects or the passage of time. The mechanics of objects based on Newton's laws of motion,...
Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
Dimensionless Groups in Fluid Mechanics
Gauss's Law
Schwarzschild Radius and Event Horizon
The minimum speed required to launch a projectile from the surface of an object to which it is gravitationally bound so that it eventually escapes the object’s gravitational field is called the escape velocity. The escape velocity is independent of the mass of the object. Merging the idea of escape velocity with the...
You might also read
Related Articles
Articles linked to this work by shared authors, journal, and citation graph.
A minimalist account of agency in physics.
Black Hole Singularity Resolution in Unimodular Gravity from Unitarity.
The quantum gravity seeds for laws of nature.
Related Experiment Video
Updated: May 9, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
Cosmology from group field theory formalism for quantum gravity.
Steffen Gielen1, Daniele Oriti, Lorenzo Sindoni
1Riemann Center for Geometry and Physics, Leibniz Universität Hannover, Appelstrasse 2, 30167 Hannover, Germany. sgielen@perimeterinstitute.ca
We found quantum gravity condensate states that act like homogeneous spatial geometries. Their dynamics yield a modified Friedmann equation, offering a new way to study cosmology from quantum geometry.
Area of Science:
- Quantum gravity
- Cosmology
- Condensed matter physics
Background:
- Group field theory (GFT) provides a fundamental framework for quantum gravity.
- Understanding the emergence of classical spacetime from quantum geometry is a key challenge.
Purpose of the Study:
- To identify and characterize macroscopic states within GFT.
- To derive effective cosmological dynamics from fundamental quantum gravity.
Main Methods:
- Identifying condensate states in GFT.
- Extracting dynamics analogous to quantum fluids.
- Applying semiclassical (WKB) approximation.
Main Results:
- Identified condensate states interpretable as homogeneous spatial geometries.
- Derived a nonlinear, nonlocal extension of quantum cosmology.
- Showed a modified Friedmann equation arises from GFT with Laplacian kinetic terms.
Conclusions:
- This work presents the first general procedure to extract effective cosmological dynamics from quantum geometry.
- The findings bridge quantum gravity and observable cosmology.

