Cosmology
The big bang and all the rest: The geometry of the universe, the formation of the first light chemical elements, cosmology and quantum gravity
This page features an overview of all our Spotlights dealing with cosmology. In the category Basics, you will find some more information about the big bang models, their predictions and cosmological observations, notably about the cosmic background radiation. Under Cosmology and quantum gravity there are some texts about the cosmological consequences of the current attempts to describe quantum theory and general relativity in a unified setting. Physics in the background features a Spotlight giving background information that is useful for a deeper understanding of the Spotlight texts presented on this page.
Useful background information can be found in our introduction Elementary Einstein, especially in the chapter Cosmology.
Basics
A tale of two big bangs
In cosmology, “big bang” has two different meanings – and if you want to understand what’s going on, you should be aware of that difference.
The shape of space
The different space geometries allowed by the big bang models – do we live on a hypersphere?
The mathematical universe
Why cosmology is not only a matter for astronomers and physicists, but also for mathematicians
The cosmic background radiation
Cosmic Sound: Curvature and the cosmic background radiation
How the spatial geometry of the universe can be derived by observing the cosmic background radiation
The first chemical elements
Big Bang Nucleosynthesis: Cooking up the first light elements
How the first nuclei of helium, lithium and other light elements were cooked up shortly after the big bang
Equilibrium and Change: The physics behind Big Bang Nucleosynthesis
The physics behind Big Bang Nucleosynthesis, the period shortly after the big bang that saw the first production of light elements such as helium and lithium
Elements of the past: Big Bang Nucleosynthesis and observation
How to reconstruct the abundances of light elements shortly after the big bang, and thus test some important predictions of the big bang models against observation
Cosmology and quantum gravity
More information about possible cosmological consequences of the attempts to formulate a theory of quantum gravity.
Searching for the quantum beginning of the universe
About attempts to understand the beginning of our universe using different approaches to quantum gravity
Avoiding the big bang
The collapsing and then re-expanding quantum universe that loop quantum gravity offers as a replacement of the standard big bang models
Taming infinity with loops
How loop quantum gravity could replace the absurd state of infinite density, the big bang with which, according to Einstein’s relativity, the universe began
Physics in the background
Heat that meets the eye
The connection between temperature and the emission of electromagnetic radiation, as well as the consequences for stars, matter disks around black holes, and cosmology