Killing horizon

From Wikipedia, the free encyclopedia

A Killing horizon is a null hypersurface on which there is a null Killing vector field. (Killing fields are named after Wilhelm Killing.)

Associated to a Killing horizon is a geometrical quantity known as surface gravity, κ. If the surface gravity vanishes, then the Killing horizon is said to be degenerate.

Exact black hole metrics such as the Kerr-Newman metric contain Killing horizons which coincide with their event horizons, however it should be emphasised that these two notions of horizon are independent. For this spacetime, the Killing horizon is located at

r = r_+ := M + \sqrt{M - Q^2 - J^2/M^2}.

In the usual coordinates, outside the Killing horizon, the killing vector field \partial / \partial t is timelike, whilst inside it is spacelike. The temperature of Hawking radiation is related to the surface gravity by TH = κ / 2π.

De Sitter space has a Killing horizon at r = \sqrt{3 / \Lambda} which emits thermal radiation at temperature T = (1 / 2 \pi) \sqrt{\Lambda / 3}.


 This astronomy related article is a stub. You can help Wikipedia by expanding it.
 This mathematics-related article is a stub. You can help Wikipedia by expanding it.
This relativity-related article is a stub. You can help Wikipedia by expanding it.
Retrieved from "http://en.wikipedia.org../../../k/i/l/Killing_horizon.html"
Advanced Search
Included Web Search Engines


Safe Search

close

Top Matching Results

Occasionally Search.com will highlight specialized results that are based on the context of your query. Examples of specialized results include specific links to news, images, or video.

Top Matching Results may highlight information from other Search.com pages, content from the CNET Network of sites, or third party content. The listings are based purely on relevance. Search.com does not receive payment for listings in this section but our partners that provide this data may get paid for listing these products.

Sponsored Links

This section contains paid listings which have been purchased by companies that want to have their sites appear for specific search terms and related content. These listings are administered, sorted and maintained by a third party and are not endorsed by Search.com.

Search Results

Search.com sends your search query to several search engines at one time and integrates the results into one list which has been sorted by relevance using Search.com's proprietary algorithm. You can customize the list of search engines included in your metasearch from the preferences.

The search engines that are used in your metasearch may allow companies to pay to have their Web sites included within the results. To view the Paid Inclusion policy for a specific search engine, please visit their Web site. Search.com does not accept payment or share revenue with any search engine partner for listings in this section.