[extropy-chat] Impact Effects

[Amara Graps]

Russell Wallace russell.wallace at gmail.com
>while they do use the relativistic energy
>equation, their model is explicitly designed to handle meteors, not science
>fiction projectiles travelling at a large fraction of lightspeed, and I
>would still expect a relativistic impactor on hitting atmosphere to turn
>into a beam of plasma rather than several discrete chunks (how wide a beam,
>I don't know).


Shock waves occur in relativistic conditions too (many phenomena in
space). Plasmas are created on Earth laboratories for extreme
conditions. These are both physical phenomena where one can get
numbers. For parameters one would use the relativistic parameters. It
seems to me that if one knows the conditions for a shock in Earth's
atmosphere, conditions for vaporization, creating a plasma cloud, and
so on, which are given in that paper, and focuses on the basics:
energy (temperature), pressure, then it's a good start. We can't say
we know nothing, when in fact we know quite a lot.

Amara

-- 

********************************************************************
Amara Graps, PhD          email: amara at amara.com
Computational Physics     vita:  ftp://ftp.amara.com/pub/resume.txt
Multiplex Answers         URL:   http://www.amara.com/
********************************************************************
"It is intriguing to learn that the simplicity of the world depends
upon the temperature of the environment." ---John D. Barrow