Re: opposite of relativistic time contraction

Tim Little wrote:
> On 2008-03-14, Ben Crowell <crowell07@[EMAIL PROTECTED]
>
wrote:
>> Suppose we have an intelligent species with control over godlike
>> amounts of matter and energy.
> [...]
>> For instance, maybe this observer wants to be able to play chess, and
>> have 10x more time to think about his moves than he otherwise
>> would have. Is this possible?
> 
> It should be: I think the ergosphere of a suitably spinning Kerr black
> hole might have the required property (but too lazy to check).
> Certainly something just short of a Tipler cylinder should suffice.
Interesting -- thanks, I'll check into that.

> 
> 
>> It's easy to apply a large acceleration for a short time: just move
>> a microscopic black hole close to him, and you can easily obtain
>> accelerations of, say, 1000 m/s2 with negligible tidal effects,
>> without getting him anywhere near its microscopic event horizon.
> 
> That's exactly reversed: microscopic black holes have greater tidal
> stresses for a given acceleration than larger ones.

I probably expressed myself badly. I wasn't trying to
say that a microscopic black hole would have smaller
tidal forces for a given acceleration. It's just that if you've
got to accelerate the black hole, it's a lot easier to accelerate
a microscopic one.