Consider a de-Sitter universe with exponential expansion (cosmological constant dominated). As explained here:(adsbygoogle = window.adsbygoogle || []).push({});

http://math.ucr.edu/home/baez/end.html

such an universe does not tend to a thermal death, or to a 0° K state, but to a state with a constant temperature above 0 °K (prof. Baez estimates 10^-30 °K). After this temperature is reached, it will remain constant regardless of the susequent expansion of space. This is due to the fact that the cosmological horizon radiates in a similar way that observers in a Rindler space are immersed in an Unruh radiation.

With my very limited knowledge about QFT, I understood qualitatively the reason for the Unruh radiation (creation and annihilation operators are defined in different ways for Minkowski and Rindler spaces, which leads to different gound states of the Hamiltonian) and I found that it depends directly on the acceleration (T = a / 2 pi).

My assumption is that the same (or a similar) derivation applies for a de-Sitter universe and that the temperature does also depend on the acceleration. Correct?

But then the following question raises: if the acceleration is not constant and is growing exponentially, does this mean that the temperature in a de-Sitter universe will grow due to this effect? This seams very strange to me…

Thanks.

**Physics Forums - The Fusion of Science and Community**

Join Physics Forums Today!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

# Final temperature in a de-Sitter universe

Loading...

Similar Threads - Final temperature Sitter | Date |
---|---|

B North and South poles of Mars are at different temperatures? | Wednesday at 5:45 PM |

Cassini's Grand Finale | Apr 7, 2017 |

I Artificial Stars for testing telescopes: the final answer? | Jul 10, 2016 |

M51 photo (finally) | Apr 13, 2015 |

Calculate the final velocity of an object accelerating towards a mass | Feb 26, 2010 |

**Physics Forums - The Fusion of Science and Community**