h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

If a black hole was spinning fast or slow (I can't remember which), you will get into the black hole without 'spagettification'... you guess what that is!

According to Stephen Hawking's 'A Brief History of Time', there is no difference between a rotating or non-rotating black hole in terms of the effects on an object. All objects will get stretched apart (spaghettified?) by the tremendous forces acting on them. And there's no truth in the 'doorway to another universe' theory, again according to Hawking. All black holes end in a singularity. Still haven't got my head round those, though.

Not quite... Kerr's solution is superior compared with Schwarzchild's as all black holes will rotate in practice so there will be an opening to another universe. Kerr's solution shows a doughnut shaped event horizon that has a wormhole through the centre 'hole'.

All the equations presuppose that another universe exists on the opposite side in order that the equations don't explode. The Kerr wormhole would therefore act as a form of Riemman cut. Also the equations open the possibility for "baby universes" that form in a loop of the Kerr wormhole at the location of maximum gravity.

It is true that there will be a lot of gravity in the wormhole but as long as there isn't a singularity then it would be possible with sufficiently advanced technology to send a team through

Right. I also recall reading a book that showed that a spinning and electrically charged hole would have a donut shaped singularity. It would then be possible to dive through the donut, while avoiding the crush.

The article suggests that the event horizon (EH) is the "weird" place, where indescribable things happen.

In fact, the EH (at least for the person falling into the hole) isn't that weird. It's the singularity in the middle that has all the strange physics-breaks-down-here kinda stuff.

Anyway, for some current info, here's this week's New Scientist article on Black Holes: http://www.newscientist.co.uk/features/features_22323.html

There was also an article recently (again in New Scientist) that showed how scientists were trying to make pseudo-Black Holes in the lab by slowing down the light to a snail's pace.

Regards, jd

The EH is only wierd from the outside - it's where all things that fall in look like they end up.

Howdi!
Slight wierd theory erupting here (please feel free to tell me how wrong i am, i don't actually know what i'm talking about). What if the singularity is a kind of nexus - if you've seen Star Trek Generations then ul know what i mean. Supposedly all laws of physics like time, etc. break down there so what's to say that when in it, you can't go anywhere in time and the universe that u want?
of course the only problem is getting there without being, what was it, spagettified (must remember that one for my physics class).
oh well, we can dream
idwoh!