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touqra
Feb7-06, 12:15 PM
What is the difference between particle horizon and cosmological event horizon?

Garth
Feb7-06, 01:37 PM
What is the difference between particle horizon and cosmological event horizon?
The Particle Horizon is the limit of what we can see today, (it takes longer than the present age of the universe for light to reach us from beyond the PH), the Event Horizon is the limit of what we may ever see, even if we wait for ever. (the EH is determined by the geometry and expansion history of the universe)

Garth

touqra
Feb7-06, 07:13 PM
the Event Horizon is the limit of what we may ever see, even if we wait for ever. (the EH is determined by the geometry and expansion history of the universe)

Garth

Could you elaborate further on the Cosmological EH?

SpaceTiger
Feb7-06, 08:02 PM
Could you elaborate further on the Cosmological EH?

Here are some more event horizon discussions

http://www.physicsforums.com/showpost.php?p=845204&postcount=7
http://www.physicsforums.com/showthread.php?p=885213

chronon
Feb8-06, 03:35 AM
You may also be interested in articles on my website

The Cosmological Event Horizon (http://www.chronon.org/articles/Cosmological_Event_Horizon.html)

Cosmological Horizons (http://www.chronon.org/articles/cosmichorzns.html)

Chronos
Feb9-06, 02:29 AM
The horizons thing creates more confusion than clarity, IMO. In our [observable] universe, the surface of last scattering is the observational limit - again IMO. Super-hubble fluctuations may have left trace imprints on the CMB - albeit that is debatable - but in a temporally bounded BB universe, it is impossible to observe entities that [may or may not have] existed prior to recombination.