(urth) Problematic element in chronology - Red Giants

[Gerry Quinn]

From: "Jeff Wilson" <jwilson at io.com>
> On 5/30/2011 1:21 PM, Gerry Quinn wrote:
>>
>> From: "Jeff Wilson" <jwilson at io.com>
>>> On 5/29/2011 7:48 PM, Gerry Quinn wrote:
>>
>>>> I don't think the issue of small black holes matters to BotNS - the
>>>> black hole described is absorbtive, and thus large enough to have a low
>>>> temperature. In the context of black holes, there's actually not much
>>>> margin between the temperature of a stellar interior and that of outer
>>>> space. They are either colder or hotter than either, and those that
>>>> persist are certainly colder.
>>>
>>> Where is it described?
>>
>> Standard theory (you can find it in Wikipedia etc.)
>
> I mean, where is the black hole described in BotNS? How is it 
> characterized sufficiently to make those proceeding inferences?

It's described as black.  That gives it a minimum mass of something like 
10^18 tons and a temperature under (say) 500 C.  So it's not what we think 
of as a mini black hole, and it will last for billions of years (except 
maybe if it interacts with a White Fountain).

>> of a black hole inversely proportional to its mass. A solar mass black
>> hole has a temperature of about a ten millionth of a degree. An
>> earth-mass black hole has a temperature of a fiftieth of a degree.
>
> Something on the order of an earth-mass black hole with hand-sized even 
> horizon is what I had in mind. This would imply that the White Fountain 
> would be of a similar magnitude and why it would do such a job on Urth as 
> it passed along.
>
>> In truth it's hard to imagine that it would have the effects
>> described
> > in BotNS; I assume Wolfe is winging it.
>
> Oh, of course. I'm just saying that a hypermass of a vague order of 
> magnitude can have effects that qualitatively resemble what's in the book.

I too think that it is supposed to be that size.  Realistically I find it 
hard to imagine a black hole injected into the Sun doing anything other than 
age it prematurely, which will make it hotter, rather than colder.  For the 
purposes of the story, I ignore that - and I would not expect the majority 
of readers to even have an opinion on the subject.  My physics may be wrong 
or right, but even to have such an opinion I probably need to know more 
physics than most.  If one doesn't think about it too much, a cooling effect 
is plausible.

And maybe, as David Stockhoff suggests, it is intended just to act like a 
drain.  Perhaps the Hieros can make it work that way.

- Gerry Quinn