upon entering any world, Mincraft crashes.

This is what Minecraft tells me:

[10:47:50] [Client thread/INFO]: Setting user: mc_is_awsome
[10:47:50] [Client thread/INFO]: (Session ID is token:686f6ab47f2646028a4887de2e6ca0a5:1a0f244c1e9548869582e8ea821672c5)
[10:47:51] [Client thread/INFO]: LWJGL Version: 2.9.1
[10:47:52] [Client thread/INFO]: Reloading ResourceManager: Default
[10:47:53] [Sound Library Loader/INFO]: Starting up SoundSystem...
[10:47:53] [Client thread/WARN]: File minecraft:sounds/mob/ghast/fireball.ogg does not exist, cannot add it to event minecraft:item.fireCharge.use
[10:47:53] [Thread-6/INFO]: Initializing LWJGL OpenAL
[10:47:53] [Thread-6/INFO]: (The LWJGL binding of OpenAL. For more information, see http://www.lwjgl.org)
[10:47:53] [Thread-6/INFO]: OpenAL initialized.
[10:47:53] [Sound Library Loader/INFO]: Sound engine started
[10:47:55] [Client thread/INFO]: Created: 512x512 textures-atlas
[10:48:00] [Server thread/INFO]: Starting integrated minecraft server version 1.8.1-pre4
[10:48:00] [Server thread/INFO]: Generating keypair
[10:48:00] [Server thread/INFO]: Preparing start region for level 0
[10:48:01] [Server thread/INFO]: Preparing spawn area: 61%
[10:48:02] [Server thread/INFO]: Changing view distance to 16, from 10
[10:48:02] [Server thread/INFO]: mc_is_awsome[local:E:bee4dbd2] logged in with entity id 362 at (154.9804760955049, 72.5, 252.1536918476562)
[10:48:02] [Server thread/INFO]: mc_is_awsome joined the game