From: Billy Brown (ewbrownv@mindspring.com)
Date: Sat Jul 31 1999 - 10:53:18 MDT
John Clark wrote:
> Billy Brown <ewbrownv@mindspring.com> Wrote:
> >If it were all neutrinos an average human would stop a grand total of
maybe
> >10^-17 % of that flux, which amounts to around 10^-7 electron volts -
> >in other words, less than one interaction.
>
> I have no idea what you're talking about. You seem to saying that a human
> body would not absorb even one neutrino from a nearby supernova, but
> you can't possibly mean that.
Actualy, yes, that is exactly what I mean. It's a only rough approximation,
of course - since you don't seem to believe it, I'll get a more detailed
computation.
> >It doesn't matter what exotic form you want the energy to arrive in,
> >because there simply isn't enough of it to do anything.
>
> To repeat myself, energy has little to do with danger, just one X ray
> photon could kill you if it hits in the right place and in fact that very
> thing is a major, perhaps the major, cause of the most feared disease
> of the 20'th century that kills millions of people every year.
A) People get hit by single X rays all the time and survive - energy density
is the major determinant of the probability that you will actually get one
of those unlucky hits. Rendering a sentient race extinct requires you to
approach 100% mortality, which means you need a very high probability, which
in turn means you need a significant amount of energy.
B) What on Earth makes you think it is realistic to expect cancer to be a
significant problem for a spacefaring civilization? Do you seriously think
that we could spend another thousand years researching the problem without
finding reliable cures? With sublight space travel, that is the kind of
timespan we need to be thinking about.
> >The target civilization will be exposed to much higher levels of
> >every type of radiation (including neutrinos) simply by living near
> > their own sun.
>
> Once more I must say that you can't possibly mean what you seem
> to be saying.
Yes, I do. If you think I'm wrong, show me the error in my calculations.
> >Do I really need to write up a complete treatment of all the
> calculations here?
>
> Yes, I rather think you do.
OK - but it will have to wait until after Extro. I'll post the URL when I
get the web page up.
Billy Brown, MCSE+I
ewbrownv@mindspring.com
This archive was generated by hypermail 2.1.5 : Fri Nov 01 2002 - 15:04:37 MST