[time-nuts] Time of death-Again

Wed Oct 27 23:26:45 UTC 2010

```jimlux wrote:
> Marshall Eubanks wrote:
>> On Oct 27, 2010, at 6:51 PM, Perry Sandeen wrote:
>>
>>> Gents,
>>>
>>> Wrote: < If you want a sub-microsecond time of death, sit on a bomb
>>> like Major T. J. "King" Kong in "Dr. Strangelove," and get your
>>> friends to time and triangulate the prompt radiation. That should be
>>> good to a few 10's of nanoseconds.
>>>
>
>
> Folks, one doesn't need a thermonuclear device for this sort of almost
> instantaneous disintegration.
>
> Standard old high explosives could get your "duration of death" down in
> the submillisecond range, and a simple optical pickup could determine
> the time when the explosion occurs to nanoseconds (after calibrating for
> light time delay).
>
> Black powder which is really a propellant might even be able to
> disassemble your corpus in less than a millisecond.
>
> However, if one needs microsecond type uncertainties, then the nuclear
> device is probably your best bet. Probably not under a microsecond
> though, from simple mechanical disassembly.  say you were standing just
> outside the approaching fireball... the fireball (in early stages) grows
> roughly at the speed of light as the photons proceed out.  The question
> would be whether there is enough flux to ionize you in a suitably short
> time.  Basically, you'd have to heat your 100kg or so up to a few
> thousand K.  Let's see.. 400kJ would heat 100kg up one degree, so 400MJ
> would get you to 1000 degrees, which is hot, but not ionized.  probably
> If you were, say, 10 meters away, and your body intercepts 1/2 square
> meter of the flux which is assumed spread evenly over 314 square meters,
> the instantaneous power of the explosion would have to be 400MJ*628 in 1
> microsecond, or about 251GJ/microsecond, or a mere 250E15 Watts
>

I forgot.. 1 kt (about the smallest practical nuclear device) is about
4.194 TJ.  Referring to my handy copy of Glasstone, 99.9% of the energy
is released in about 70 nanoseconds (the last 7 generations), and if
you're reasonably close, then the energy "pulse" hasn't had much time to
spread out, so even a small device is well over the threshold to keep
the variance in your duration of death under a microsecond.

```