Registered: Jan 2004
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Posts: 2025

I was researching this sort of thing, and came across a particularly interesting document that explored some of the known scientific possibilities behind the science fiction, from

http://members.tripod.com/da_theore.../wdphysics.html

The Warp Drive E book:

The broader scope of this E-Book is to also explore aspects of theoretical
physics which go beyond epistemology purposes and to investigate there
practical uses for the benefit of society as a whole. The specific practical
use of general relativity which this E-Book attempts to cover is how it may
be possible to use warp drive metrics as a means of allowing interstellar
communication and transportation on human time scales. This could have
several benefits for the collective world society, such as the stimulation of
economic growth, the potential for practical human colonizations of space,
the ability to protect our planet and home from celestial hazards, and the
possibility of unprecedented peaceful international cooperation amongst all
nations. While these benefits may not be realizable at present given time
they should begin to reveal themselves and this the authors feel should be
the direction in which the physical sciences should follow. It is hoped that
the practical uses of the theoretical possibilities known today may lead to
iii
this direction and it is hoped that this document serves as a good start for
this vision of the future

13.2.1 Hull Materials
The three main materials used for the hull of a spacecraft are: For the hull, a
mix of mainly Aluminum and Magnesium; for the supports that hold the hull
together mostly Titanuim is used. These materials are very strong and very
light. Hopefully even better materials will later be discovered that are even
more efficient. However, future spacecraft of the starship type will require far
128 CHAPTER 13. SHIP STRUCTURE REQUIREMENTS
different materials in part of their hulls. One aspect, brought up earlier is the
need to produce a variable barrier for quantum tunneling. This will require
some form of smart material that can vary its properties via electrical control.
This could be a surface coating over a regular hull skin or take the actual
form of part of the hull itself in the area of the field generator. Secondly,
if the EM transtator method is utilized an embedded system of waveguides
will have to be incorporated into the hull structure to emit the transtating
field itself. Smart materials will most likely hold the key to such a crafts
production. Materials that can alter their strength and tensil properties to
compensate for stresses involved during flight will have to be developed.
Even given the external radiation shield ability better methods on internal
radiation shielding without excess weight will have to be developed along
the way especially if atomic power is utilized for power generation. As to
those present materials since a Starship has less weight requirements I would
suggest Titanuim based alloys are the way to go here.
Internal wise composites are the way to go. In an advanced society like
ours we all depend on composite materials in some aspect of our lives. Fibreglass,
developed in the late 1940s, was the first modern composite and is
still the most common. It makes up about 65 per cent of all the composites
produced today and is used for boat hulls, surfboards, sporting goods, swimming
pool linings, building panels and car bodies. Most composites are made
up of just two materials. One material (the matrix or binder) surrounds and
binds together a cluster of fibres or fragments of a much stronger material
(the reinforcement). One modern advance has been Carbon based composites
which are both strong and lightweight. Certain spacecraft parts could
be fashioned from this material.
Ceramics, carbon and metals are used as the matrix for some highly
specialised purposes. For example, ceramics are used when the material is
going to be exposed to high temperatures (eg, heat exchangers) and carbon
is used for products that are exposed to friction and wear (eg, bearings and
gears). Here again these have applications in starship design.
Kevlar is a polymer fibre that is immensely strong and adds toughness
to a composite. It is used as the reinforcement in composite products that
require lightweight and reliable construction (eg, structural body parts of an
aircraft). Composite materials were not the original use for Kevlar - it was
developed to replace steel in radial tyres and is now used in bulletproof vests
and helmets. Its present usage in aircraft could be adapted to spacecraft
usage.
13.2. STRUCTURAL REQUIREMENTS 129
In thinking about starship designs it is worth remembering that composites
are less likely than metals (such as aluminium) to break up completely
under stress. A small crack in a piece of metal can spread very rapidly with
very serious consequences (especially in the case of aircraft). The fibres in a
composite act to block the widening of any small crack and to share the stress
around. They also have the advantage of being able to easily be sealed which
for spacecraft is a plus. It is possible with near term future developments in
this area for the whole structure of a spacecraft to be built from composites.
Even the circuits of the electronic equipment could be grown and etched into
these composite materials just as we now use composite based boards for our
intergrated circuit systems. This would give use a smoother layout for our
craft. SENSOR EQUIPMENT
When man first ventures to the stars sensors for such a craft will have to
be developed. We will not only need the normal sensors like radar, IR, EM,
etc. We will need sensitive gravity wave detectors, sensors designed to detect
signs of biological activity, telescopic systems designed to detect planets at
a vast distance. The list goes on. We will also have to have these tied into a
dedicated computer system to sort through the information.
Navigation alone will require its own sensor systems and a means of properly
plotting a cource in areas no one has traveled before. Information gathered
along the way will help update our navigational data as we explore
outward. I would suggest that pulsers could be used as reference points to
determine our position as we travel. But an initial map based upon data
we have at present would have to be built into the computer systems data.
Also an extensive database of information will be needed by the craft in the
event of trouble since at present without some means of FTL communication
a starship would not have the luxery of calling home for advice and help.
COMPUTER SYSTEMS Computers will have to be designed to network
on a starship. The Computer behind navigation has to interface with not
only the propulsion of Engineering computer, it also has to interface with
the science monitoring computer tied to the sensors, and with life support
computer control. Fiber optics hold promise in the network of this system
as well as advanced multiprocessors. Another area is quantum computers, if
developed they could vastly increase the processing speed and memory of a
starship computer system.
In the area of networking we are looking at something better than a T3
connection between each sub-system in the net. Speed is vital on a craft
traveling in excess of the speed of light. On the autoban when doing over
130 CHAPTER 13. SHIP STRUCTURE REQUIREMENTS
100 MPH if a car pulls out in front over a mile ahead you break to slow
down. In space at these speeds you have to be able to drop from warp or
change your course faster than man has ever achieved before. At present not
only are our sensor systems too slow. Even our computer systems are slow
compared to what is needed. At C, traveling at 186300 MPS even .000001
second equals .1863 miles. Take that example and figure it for say 100C
and you have 18.63 miles in 1 milisecond. At 1000C you have 186.3 miles
in the same time. Even though our present computers operate faster than
a millisecond they are still somewhat slow for the task given the main bus
speed for interface to external devices. This is one area that will require
further advances.

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Registered: Jul 2000
Location: A New England
Posts: 9166

If that is the Lawrence Krauss book, I thought it was pretty interesting.

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