Methane threatens to bake humanity like Turkeys in an Oven

On Feb 4, 4:44 pm, wrote:
On Feb 4, 12:43 pm, Saul Levy wrote:

More DOOM AND GLOOM FOREVER! Nothing we can do about it anyway so all
the talk is just that, talk!

Saul Levy

You are a simple man. Why the f would anyone want to invent global
cooling.

A bit of introspection vs. respection (nationalism), a war of climate:
this
temperature is too cold here, this temperature is too hot here.

On 4 Feb, 17:17, "George Dishman" wrote:
"Ian Parker" wrote in message

Ion drive to lift from the Moon? Not even close. From
a small asteroid with microgravity perhaps but you then
still have to get it to L1. In fact what ou would do if
the manufacturing technology was available would be to
land a mass driver on the asteroid, push it to the right
location, then start processing at that point. You don't
want to be moving a vast thin plate around and coping
with the tidal forces as it passes the Earth.

Lift from an Asteroid. Of course you can't have ion drive from the
Moon. As far as manoevering a thin plate is concerned. In point of
fact that would be easier in space than a solid mass. After
manufacture it could be used to concentrate sunlight and fuel the ion
drive.

As far as tidal forces are concerned. These are taken care of in your
gravitational calculation. All spacecraft to the outer solar system
have used slingshots. We are well used to performing the calculations
needed to traverse complex gravitational fields.
What I propose is similar to George Bush's return to the Moon -
only with one difference - No astranauts. The moror skills of an
astronaut can be replicated completely by machines.

We are nowhere close to that level of technology. The
rovers on Mars are the best. If there was an astronaut
there, he could blow the dust ou of the failed motors
and get them working again. The rovers can't even do
that and if they could it would still take a human
operator to control it remotely. A computer could
easily detect the motor had failed but wouldn't be
able to work out why or how to repair it and again we
are many years away from anything like that capability.

How much is the ISS and NASAs infatuations costing? A far lower sum
would bring capabilities up. You are right though to focus on the low
level of achievment of NASA. In fact games distributors are doing
better than NASA. If we break the problem down into its logical
components we have at its bare bones a problem in dynamics. Now
dynamical systems are inherently predictable. They consists of
matrices and transfer functions. CAD/CAM systems already do good
simulations. Robots are now starting to be developed using Javalink. I
will again point to the basic infatuation and failure of NASA.
Progress is being made by CAD/CAM manufacturers, games (quite
surprisingly) Sonic the hedgehog stands a far better chance of
repairing Hubble than ever NASA has and of couse general manufacturing
industry.

As far as working out why a component had failed. This is quite
simple. How would we do it? Well we would probably take a circiut
diagram, put probes on the various points. We would check the
continuity of circuits in (for example) the coils before coming to the
conclusion that the armature had burned out. If we had a new part we
would then repair the motor. If we did not have the part a robot could
not repair it, but then neither could an astronaut. In fact the
example you give is a rather poor one because car firms like Ford
ALREADY have a plug into which you can place a probe and a computer
then dianoses the fault. It is in fact an integral part of an engine
management system. My car has its ABS controlled from EMS and
increasingly a variety of functions are going onto EMS. I could sttick
a probe in drive the car and proform an emergency stop while going
fast round a corner on a wet road. The system will tell me what is
happenning, and any faults with ABS. Expert systems are in fact used
in fault diagnosis including medicine - which is really just another
form of fault diagnosis and repar. The barrier is not the ability of
the system to diagnose it is patient acceptability and the fact that
diaglogue has to be done via NL (elastic station The season of spring
= La estacion de ressorte). In a car we do not use NL and a probe on
EMS is a lot simpler.

How far should Ford take it? It depends on whether they are paying
their mechanics $180 million a week
OK one might say
can you automate everything.

You might, the rest of us have a much better grasp on
reality.

We are not talking here about emotion or any real deep thought
process, we are simply talking about analyzable dynamical systems. In
fact a task can be viewd as the solution of equations something that
has been done for yonks.

Out of what? The closest we have got so far is to assemble
blocks that have already been constructed:

http://www.news.cornell.edu/stories/...elfrep.ws.html

That is vastly different from sending a machine to an
asteroid. The simplest chips in those blocks took billion
dollar fabs to manufacture and that is after the silicon
and dopants have been mined, refined and grown into crystals.


No it isn't! Point is that an asembly from pre prepared components can
be viewed as a dynamical task. The basic Pons Assinorum is the ability
to perform a dynamical task. Producing the robot itself (not from pre
prepared components) can be broken down into a series of dynamical
tasks. If our task is in CAD/CAM we have a desciption of it which a
robot can understand. If we can describe an astronaut's task on the
Moon (or better still an asteroid) and can break down all the
processes into simple steps which can be described dynamically we can
construct a Von Neumann swarm. We should really talk about a swarm not
a machine if we are speaking strictly. We can in fact construct a
definition of a VN swarm along the following lines. We have a number
of processes each with inputs and outputs. The inputs could be
assemblies like a flatpack or they could be sunlight and asteroid
rock. Outputs for some processes are inputs for other processes. We
take the sum of the ensemble. When the only inputs, which are not
matchable by outputs is sunlight and rock we will have achieved the
goal. In fact if we have processes floating around in a CAD/CAM system
we need an algorithm (possibly a GA) to get the fittest solution.
Those who are interested in the origin of life might care to ponder
how a similar sort of algorithm might have operated in ponds some 3.8
billion years ago.

Can we go the whole way in one go? I think that as a first stage
complex chips should be blasted from Earth in rockets.

We will achieve what you are considering eventually using AFM

http://www.almaden.ibm.com/vis/stm/atomo.html

http://research.chem.ucr.edu/groups/bartels/

but we are _many_ decades away from using it for macroscopic
objects.

The NASA establishment
seems to believe in something like "Intelligent Design" (As does the
boss) Astraunauts seem to be enddowed with the kind of "vital force"
postualated by (some) 19th century chemists. My contention is that
anything an astranaut can do a machine can do - probably better.

Go ahead then, see if you can get farther than Cornell.
Or just publish the drawings for a self-contained machine
nanotech machine that can make a copy of itself out of a
lump of raw asteroid using AFM without any preprocessing.

I am endeavoring to show how to do it. I am in fact a retired
scientist and my aim is to interest other people in worthwhile
projects. Nanotech is frequently talked about. The best route to VN is
via CAD/CAM. Nanotech is problematic when doing anything other than
reproducing itself. CAD/CAM will make anything compliant.

Stanford and Cornell are doing a great job - don't get me wrong. My
only criticism is that Andrew Ng to take an eample is also qworking on
linguistics - writing some great papers by all account. However we
would move faster with a TOTALLY DEDICATED effort. I think people like
IKEA and B&Q should sponsor students. If I were a university teacher I
would feel the need to teach a balanced AI course. To be a teacher a
Spanish, just as every teacher is "a teacher of English".

As far as total amounts are concerned. This has in fact already been
discussed by other people (see sci.space.policy) 1/10 of the area of
the Earth's circumferance has been discussed. In the case of VN the
weight is largely irrelevant. A non VN Earth transportable solution
with mirrors weighing 55kg/km^2 has been proposed. Rigidity is not in
fact a probem. If you did want a rigid structure you would spin it.

Nope. If you spin it face on between the Earth and Sun
today, it is edge on in three months :-( It will spin
once a year on an axis perpendicular to the ecliptic.

You are right. However as I have said a non rigid solution would be
what you would probably go for.

Think what the forces would be if a CME hit one side of
the shield. Has anyone calculated that or the strength
needed to avoid destruction? Your are talking about an
emormous mass to make this survivable.

NO - we can still think about spin but now in a gedanken sense. The
oder of magnitude of forces at L1 will be 5km/h. This is not an
enormous force. I talk in terms of speed since the strength required
has the dimensions of speed. I fact it need not be strong at all.


That is the whole point about methane. This will not work.

The point is to reduce the heating below the threshold
for the positive feedback in the methane release to
overcome the natural negative feedback in the rest of
the biosphere.

Fossil sources will run out eventually so it's a bullet
we will have to bite sooner or later. Of course, while
it is a logical solution, it is as feasible politically
as your sunshade is economically.

It is economic. Once a seed is developed it is fire and forget (not
quite you still need to control it).

Sure, but we won't have that sort of technology until late
in the century at best - too late for sure.

How come we will be getting strong AI according to Blair's think tank?


- Ian Parker

On 5 Feb, 02:52, wrote:

A bit of introspection vs. respection (nationalism), a war of climate:
this
temperature is too cold here, this temperature is too hot here.

Yes indeed. One question I would like to ask. If you could sail from
St Petersburg to Vladivostok across the Arctic Ocean thereby saving
thousands of kilometers of steaming would people want to go back to
the Cape or Suez? Climate change cure has to be flexible. I think we
should be asking that kind of question.


- Ian Parker

On 5 Feb, 10:59, "Ian Parker" wrote:
On 4 Feb, 17:17, "George Dishman" wrote: "Ian Parker" wrote in message

Ion drive to lift from the Moon? Not even close. From
a small asteroid with microgravity perhaps but you then
still have to get it to L1. In fact what ou would do if
the manufacturing technology was available would be to
land a mass driver on the asteroid, push it to the right
location, then start processing at that point. You don't
want to be moving a vast thin plate around and coping
with the tidal forces as it passes the Earth.

Lift from an Asteroid. Of course you can't have ion drive from the
Moon. As far as manoevering a thin plate is concerned. In point of
fact that would be easier in space than a solid mass. After
manufacture it could be used to concentrate sunlight and fuel the ion
drive.

The focus would be far from the plate and any thrust
would cause it to buckle.

As far as tidal forces are concerned. These are taken care of in your
gravitational calculation. All spacecraft to the outer solar system
have used slingshots.

Spacecraft are small, the plate is immense. Tidal
forces arise because the gravity on one side differs
from that on the other and would tend to pull a thin
structure apart.

We are well used to performing the calculations
needed to traverse complex gravitational fields.

Sure, you can calculate the force easily but you still
have to build something strong enough to withstand
those forces.

What I propose is similar to George Bush's return to the Moon -
only with one difference - No astranauts. The moror skills of an
astronaut can be replicated completely by machines.

We are nowhere close to that level of technology. The
rovers on Mars are the best. If there was an astronaut
there, he could blow the dust ou of the failed motors
and get them working again. The rovers can't even do
that and if they could it would still take a human
operator to control it remotely. A computer could
easily detect the motor had failed but wouldn't be
able to work out why or how to repair it and again we
are many years away from anything like that capability.

How much is the ISS and NASAs infatuations costing?

A tiny fraction of the cost of building smelters and
manufacturing plant to process your asteroid in
orbit. The ISS would be nothing more than a
proof-of-concept prototype for your idea.

A far lower sum
would bring capabilities up. You are right though to focus on the low
level of achievment of NASA.

I never mentioned them, you keep ranting on about
them. I'm not interested in your political ravings.

As far as working out why a component had failed. This is quite
simple. How would we do it? Well we would probably take a circiut
diagram, put probes on the various points. We would check the
continuity of circuits in (for example) the coils before coming to the
conclusion that the armature had burned out. If we had a new part we
would then repair the motor. If we did not have the part a robot could
not repair it,

Exactly.

but then neither could an astronaut.

Yes he could, he could unwind the coil, fix the break
and rewind it. I've done that. The whole point is that
a robot can only do the repairs it was designed for
in advance while a human can improvise. It's not
about inteligence, the difference is dexterity.

In fact the
example you give is a rather poor one because car firms like Ford
ALREADY have a plug into which you can place a probe and a computer
then dianoses the fault.

Yes, and then a humnan has to do the repair, that's
the part you are missing all the time.

It is in fact an integral part of an engine
management system. My car has its ABS controlled from EMS and
increasingly a variety of functions are going onto EMS. I could sttick
a probe in drive the car and proform an emergency stop while going
fast round a corner on a wet road. The system will tell me what is
happenning, and any faults with ABS. Expert systems are in fact used
in fault diagnosis including medicine - which is really just another
form of fault diagnosis and repar. The barrier is not the ability of
the system to diagnose it is patient acceptability and the fact that
diaglogue has to be done via NL (elastic station The season of spring
= La estacion de ressorte). In a car we do not use NL and a probe on
EMS is a lot simpler.

How far should Ford take it? It depends on whether they are paying
their mechanics $180 million a week

OK one might say
can you automate everything.

You might, the rest of us have a much better grasp on
reality.

We are not talking here about emotion or any real deep thought
process, ..

Right, we are talking about the ability to do physical
changes to hardware.

we are simply talking about analyzable dynamical systems. In
fact a task can be viewd as the solution of equations something that
has been done for yonks.

Solving equations never repaired a toaster.

Out of what? The closest we have got so far is to assemble
blocks that have already been constructed:

http://www.news.cornell.edu/stories/...elfrep.ws.html

That is vastly different from sending a machine to an
asteroid. The simplest chips in those blocks took billion
dollar fabs to manufacture and that is after the silicon
and dopants have been mined, refined and grown into crystals.

No it isn't! Point is that an asembly from pre prepared components can
be viewed as a dynamical task. ....

Point is - there are NO pre-prepared components! All
you have is a few boulders and maybe some ice. It
is getting from that to the parts that is the task. Bolting
the parts together is trivial.

We will achieve what you are considering eventually using AFM

http://www.almaden.ibm.com/vis/stm/atomo.html

http://research.chem.ucr.edu/groups/bartels/

but we are _many_ decades away from using it for macroscopic
objects.

The NASA establishment
seems to believe in something like "Intelligent Design" (As does the
boss) Astraunauts seem to be enddowed with the kind of "vital force"
postualated by (some) 19th century chemists. My contention is that
anything an astranaut can do a machine can do - probably better.

Go ahead then, see if you can get farther than Cornell.
Or just publish the drawings for a self-contained machine
nanotech machine that can make a copy of itself out of a
lump of raw asteroid using AFM without any preprocessing.

I am endeavoring to show how to do it. I am in fact a retired
scientist and my aim is to interest other people in worthwhile
projects. Nanotech is frequently talked about. The best route to VN is
via CAD/CAM. Nanotech is problematic when doing anything other than
reproducing itself. CAD/CAM will make anything compliant.

Again CAD/CAM is irrelevant, the problem is the lack
of physical effectors driven by those CADCAM designs
to actually produce hardware.

Stanford and Cornell are doing a great job - don't get me wrong.

I agree, but the fact remains that there is a huge gap
between where they are now and what is needed to
manufacture anything using atomic scale methods.

My
only criticism is that Andrew Ng to take an eample is also qworking on
linguistics - writing some great papers by all account. However we
would move faster with a TOTALLY DEDICATED effort. I think people like
IKEA and B&Q should sponsor students. If I were a university teacher I
would feel the need to teach a balanced AI course. To be a teacher a
Spanish, just as every teacher is "a teacher of English".

And how would that help anyone smelt alumino-silicate
rock into aluminium scaffolding poles and solar cells?

As far as total amounts are concerned. This has in fact already been
discussed by other people (see sci.space.policy) 1/10 of the area of
the Earth's circumferance has been discussed. In the case of VN the
weight is largely irrelevant. A non VN Earth transportable solution
with mirrors weighing 55kg/km^2 has been proposed. Rigidity is not in
fact a probem. If you did want a rigid structure you would spin it.

Nope. If you spin it face on between the Earth and Sun
today, it is edge on in three months :-( It will spin
once a year on an axis perpendicular to the ecliptic.

You are right. However as I have said a non rigid solution would be
what you would probably go for.

Think what the forces would be if a CME hit one side of
the shield. Has anyone calculated that or the strength
needed to avoid destruction? Your are talking about an
emormous mass to make this survivable.

NO - we can still think about spin but now in a gedanken sense.

Nonsense, to get rigidity you need real spin and you can't
do that as explained above.

The
oder of magnitude of forces at L1 will be 5km/h. This is not an
enormous force. I talk in terms of speed since the strength required
has the dimensions of speed. I fact it need not be strong at all.

Rubbish, the typical CME has a mass of 10^9 tonne and is
moving at 500 km/s ! Your mass of 0.055 gsm is tissue
paper, fine for a small solar sail but in a non movable
configuration it wouldn't survive even the smallest CME. A
plate of hundreds of km diameter capable of surving a CME
would need to be hundreds of tonnes per km^2 and if 700 km
in diameter (I think you said 10% of the Earth diameter)
would be 35 million tonnes at 100 tonne/km^2 and more
likely to be a billion tones.

Smelting that much aluminium out of asteroidal rock
is not going to be done by Sonic the Hedgehog, even
if he can use Javalink.

Sure, but we won't have that sort of technology until late
in the century at best - too late for sure.

How come we will be getting strong AI according to Blair's think tank?

Who cares, where do you intend to get 35 million tonnes
of refined metal ?

George

On 6 Feb, 08:48, "George Dishman" wrote:

The focus would be far from the plate and any thrust
would cause it to buckle.

As far as tidal forces are concerned. These are taken care of in your
gravitational calculation. All spacecraft to the outer solar system
have used slingshots.

Spacecraft are small, the plate is immense. Tidal
forces arise because the gravity on one side differs
from that on the other and would tend to pull a thin
structure apart.

We are well used to performing the calculations
needed to traverse complex gravitational fields.

Sure, you can calculate the force easily but you still
have to build something strong enough to withstand
those forces.

I think we are talking slighly at cross purposes. There is the L1
solution which may or may not be rigid and there is the MEO solution
which is definitely NOT rigid. In fact MEO would work rather like the
quadrantal rule for aircraft in VFR. One orbital plane would consist
of rigid structures a few km across and at constant spacing and
different orbital planes would be at different heights (they need
differ by only 100m or so).

My rotation in a year was an estimate of the rough magnitude of tidal
forces on an L1 Now you can have a structure at 55Kg/km^2 in tension
quite easily, but you need a box girder type of structure for
compression. In fact you would have thin wires arranged in a fractal
like structure.

However I would like to point out a few things.

1) This approach has been advocated as an alternative to the VN
approach. With a VN appoach the weight is less important as you are
REPLICATING.

2) A rigid strucure is not really needed.

3) I think we have a little bit of confusion about 5km/h. It does not
matter how large a structure is. The important thing is the speed an
object attains in traversing it. If we build a brick wall 5m high at
10m/s^2 (10 = R&R 9.81) we have 10m/s or 18km/h.

A tiny fraction of the cost of building smelters and
manufacturing plant to process your asteroid in
orbit. The ISS would be nothing more than a
proof-of-concept prototype for your idea.

The return to the Moon is in fact proposing just that smelters. Ca you
build a smelter that is small? If you are talking about building a
sunshield you can have small pieces (even down to a cm^2) and small
tools. If you are talking about high temperature processes there is a
minimum size required. For low temperature processes you cut the
sizeProbably the best answer within current technological capabilities
is to heat by directing sunlight onto the furnace.

As I have explained nanotechnology is suspect because we want to build
any CAD/CAM object which is compliant, but it is useful for certain
processes. Clearly the further we can minaturize the basic seed the
lower will be the launch cost. Of corse because of thermal
considerations a high temperature process has an intrinsic size.
Throughout the years the size of electronic components has steadily
gone down, but we have a long way to go to DNA where a sperm contains
4GB (a DVD).
A far lower sum
would bring capabilities up. You are right though to focus on the low
level of achievment of NASA.

I never mentioned them, you keep ranting on about
them. I'm not interested in your political ravings.

I think it iss fair comment. There has been an incredible amount of
money spent on the Shuttle which is a negative achievments as costs
are twice Ariane.

Thetre is perhaps a deeper reason here. Should we be spending large
amounts of public money in a free society? Shouldn't industry be
spending the money? I tend to feel that manned spaceflight with
current technology is basically a dead end. We need to improve
technological capability.

but then neither could an astronaut.

Yes he could, he could unwind the coil, fix the break
and rewind it. I've done that. The whole point is that
a robot can only do the repairs it was designed for
in advance while a human can improvise. It's not
about inteligence, the difference is dexterity.

In fact the
example you give is a rather poor one because car firms like Ford
ALREADY have a plug into which you can place a probe and a computer
then dianoses the fault.

Yes, and then a humnan has to do the repair, that's
the part you are missing all the time.

No not if we have a flexxible robot.


We are not talking here about emotion or any real deep thought
process, ..

Right, we are talking about the ability to do physical
changes to hardware.

Yes.

we are simply talking about analyzable dynamical systems. In
fact a task can be viewd as the solution of equations something that
has been done for yonks.

Solving equations never repaired a toaster.

You have to get inside the toaster. To do this you need to perform a
series of operations. You do not need to solve equations to do them
slowly (a stepping motor can stop between each click. However to do
things with human dexterity you sure do. To repair a toaster quickly
you need to be able to lift the toaster and take it to bits moving
fast. Fast here means not being able to stop in a click but getting
the coodinates of start and destination and plotting a course. This
can be done. Watching gymnastics I recall Cassini - flybys at Venus -
Earth - Venus - Jupiter before going on to Saturn. Clearly it is
possible to work out a complex trajectory.

No it isn't! Point is that an asembly from pre prepared components can
be viewed as a dynamical task. ....

Point is - there are NO pre-prepared components! All
you have is a few boulders and maybe some ice. It
is getting from that to the parts that is the task. Bolting
the parts together is trivial.


You need a seed which consists of a VN swarm. How big this seed is
depends on a number of things - see above.


I am endeavoring to show how to do it. I am in fact a retired
scientist and my aim is to interest other people in worthwhile
projects. Nanotech is frequently talked about. The best route to VN is
via CAD/CAM. Nanotech is problematic when doing anything other than
reproducing itself. CAD/CAM will make anything compliant.

Again CAD/CAM is irrelevant, the problem is the lack
of physical effectors driven by those CADCAM designs
to actually produce hardware.

Stanford and Cornell are doing a great job - don't get me wrong.

I agree, but the fact remains that there is a huge gap
between where they are now and what is needed to
manufacture anything using atomic scale methods.

You don't need atomic scale models. You need macroscopic CAD/CAM. In
my book you are STILL macroscopic even if components are a few microns
across. See above. In fact atomic scale (a DVD on a sperm) is a
DISADVANTAGE. In fact Stanford's work is IKEA/B&Q sized.
My
only criticism is that Andrew Ng to take an eample is also qworking on
linguistics - writing some great papers by all account. However we
would move faster with a TOTALLY DEDICATED effort. I think people like
IKEA and B&Q should sponsor students. If I were a university teacher I
would feel the need to teach a balanced AI course. To be a teacher a
Spanish, just as every teacher is "a teacher of English".

And how would that help anyone smelt alumino-silicate
rock into aluminium scaffolding poles and solar cells?

You have to build a furnace using CAD/CAM. I think a solar furnace is
the solution that makes the least assumttions about technology,
although a genetically engineered organism can do mineral extraction.
In fact (as I think I said in a previous exchange with you) you can
get quite a lot of DNA by carrying on up the Amazon. You can certainly
get copper as a species of horseoe crab has copper based haemoglobin.
What Greek! Haemos is iron. Haemoglobin contains iron!

The
oder of magnitude of forces at L1 will be 5km/h. This is not an
enormous force. I talk in terms of speed since the strength required
has the dimensions of speed. I fact it need not be strong at all.

Rubbish, the typical CME has a mass of 10^9 tonne and is
moving at 500 km/s ! Your mass of 0.055 gsm is tissue
paper, fine for a small solar sail but in a non movable
configuration it wouldn't survive even the smallest CME. A
plate of hundreds of km diameter capable of surving a CME
would need to be hundreds of tonnes per km^2 and if 700 km
in diameter (I think you said 10% of the Earth diameter)
would be 35 million tonnes at 100 tonne/km^2 and more
likely to be a billion tones.

Does this matter if you have replication?

Smelting that much aluminium out of asteroidal rock
is not going to be done by Sonic the Hedgehog, even
if he can use Javalink.

2, 4 8 etc. Sonics will.


- Ian Parker

"Ian Parker" wrote in message
oups.com...
On 6 Feb, 08:48, "George Dishman" wrote:

I replied to this a few days ago but it seems to
have vanished.

As far as tidal forces are concerned. These are taken care of in your
gravitational calculation. All spacecraft to the outer solar system
have used slingshots.

Spacecraft are small, the plate is immense. Tidal
forces arise because the gravity on one side differs
from that on the other and would tend to pull a thin
structure apart.

We are well used to performing the calculations
needed to traverse complex gravitational fields.

Sure, you can calculate the force easily but you still
have to build something strong enough to withstand
those forces.

I think we are talking slighly at cross purposes. There is the L1
solution which may or may not be rigid and there is the MEO solution
which is definitely NOT rigid.

I have only been discussing the L1 approach which is
of necessity somewhat rigid. It could be a "springy"
sheet that can be deformed and return to shape but
it cannot be a simple foil or mesh which is spun.

The earth orbiting solution would a Dyson Swarm but
that is a different topic entirely.

In fact MEO would work rather like the
quadrantal rule for aircraft in VFR. One orbital plane would consist
of rigid structures a few km across and at constant spacing and
different orbital planes would be at different heights (they need
differ by only 100m or so).

No, you need multiple orbital inclinations like this

http://en.wikipedia.org/wiki/Imageyson_Swarm.GIF

or all you do is remove a thin line from the Sun. I have
seen a great web site a few years ago where a range of
swarms had been animated but I can't find it now.

My rotation in a year was an estimate of the rough magnitude of tidal
forces on an L1 Now you can have a structure at 55Kg/km^2 in tension
quite easily, ...

No you can't. Here is the lowest areal density material
I know of

http://www.space.com/businesstechnol...il_000302.html

They have achieved 5 gsm, compared to 80 gsm for typical
office paper. That is 5000 kg/km^2 (5 tonne/km^2) so
55 kg/km^2 is two orders of magnitude less than credible.

but you need a box girder type of structure for
compression. In fact you would have thin wires arranged in a fractal
like structure.

However I would like to point out a few things.

1) This approach has been advocated as an alternative to the VN
approach. With a VN appoach the weight is less important as you are
REPLICATING.

Replication is not relevant, you are making thin panels
which have no capability to reproduce because that extra
function would increase the mass. Besides which, we do not
have self-replicating technology in any form, nor are we
going to have it in the timescales of the possible methane
problem.

2) A rigid strucure is not really needed.

The material above can be folded and will restore its shape
which is what is needed. You cannot use spin for an L1
solution because the sheet must stay perpendicular to the
Earth Sun line.

3) I think we have a little bit of confusion about 5km/h. It does not
matter how large a structure is. The important thing is the speed an
object attains in traversing it. If we build a brick wall 5m high at
10m/s^2 (10 = R&R 9.81) we have 10m/s or 18km/h.

Yes, and if your shield passes the Earth edge on it is 600km
"high". If the centre is in freefall, what is the gravity at
the top and bottom? What speed do you attain falling from the
centre to the bottom (the edge nearest the Earth)?

More importantly, with an areal density of 5 tonne/km^2, what
is the tension at the centre?

A tiny fraction of the cost of building smelters and
manufacturing plant to process your asteroid in
orbit. The ISS would be nothing more than a
proof-of-concept prototype for your idea.

The return to the Moon is in fact proposing just that smelters. Ca you
build a smelter that is small?

You can, but at 5 tonne/km^2, a 700km diameter shield
has a mass of nearly 2 million tonne. Unless each
smelter load has a significant mass, the loading and
unloading times become dominant and even a large
number of smelters will be too slow. Before you go
off on a tangent about replication, forget it. Smelters
don't make more smelters, they just extract raw material.

If you are talking about building a
sunshield you can have small pieces (even down to a cm^2) and small
tools. If you are talking about high temperature processes there is a
minimum size required. For low temperature processes you cut the
sizeProbably the best answer within current technological capabilities
is to heat by directing sunlight onto the furnace.

Again, that is all sci-fi wishful thinking, we don't
have low temperature processes for separating rocks
into their constituent element and we aren't going
to have them any time in the next couple of decades.

As I have explained nanotechnology is suspect because we want to build
any CAD/CAM object which is compliant, but it is useful for certain
processes. Clearly the further we can minaturize the basic seed the
lower will be the launch cost. Of corse because of thermal
considerations a high temperature process has an intrinsic size.
Throughout the years the size of electronic components has steadily
gone down,

Yes, but the temperature needed to grow a silicon
crystal hasn't changed.

but we have a long way to go to DNA where a sperm contains
4GB (a DVD).

A far lower sum
would bring capabilities up. You are right though to focus on the low
level of achievment of NASA.

I never mentioned them, you keep ranting on about
them. I'm not interested in your political ravings.

I think it iss fair comment.

Given that you need a space-based manufacturing plant
capable of processing millions of tonnes of material
in just a few years, the ISS pales into insignificance.
It is a tiny proof-of-concept demonstrator, and cost
efficiencies on your vastly larger plant would be even
worse. It is unlikely it could survive in low orbit and
probably construction at an Earth moon Lagrange point
or farther away would be essential to avoid tidal force
problems.

....
but then neither could an astronaut.

Yes he could, he could unwind the coil, fix the break
and rewind it. I've done that. The whole point is that
a robot can only do the repairs it was designed for
in advance while a human can improvise. It's not
about inteligence, the difference is dexterity.

In fact the
example you give is a rather poor one because car firms like Ford
ALREADY have a plug into which you can place a probe and a computer
then dianoses the fault.

Yes, and then a humnan has to do the repair, that's
the part you are missing all the time.

No not if we have a flexxible robot.

We don't.

We are not talking here about emotion or any real deep thought
process, ..

Right, we are talking about the ability to do physical
changes to hardware.

Yes.

we are simply talking about analyzable dynamical systems. In
fact a task can be viewd as the solution of equations something that
has been done for yonks.

Solving equations never repaired a toaster.

You have to get inside the toaster. To do this you need to perform a
series of operations. You do not need to solve equations to do them
slowly (a stepping motor can stop between each click. However to do
things with human dexterity you sure do. To repair a toaster quickly
you need to be able to lift the toaster and take it to bits moving
fast. Fast here means not being able to stop in a click but getting
the coodinates of start and destination and plotting a course. This
can be done. Watching gymnastics I recall Cassini - flybys at Venus -
Earth - Venus - Jupiter before going on to Saturn. Clearly it is
possible to work out a complex trajectory.

Sure, we can calculate all sorts of complex stuff, but
a calculation never repaired a toaster, you need the
ability to manipulate material before any of that is
of any use.

No it isn't! Point is that an asembly from pre prepared components can
be viewed as a dynamical task. ....

Point is - there are NO pre-prepared components! All
you have is a few boulders and maybe some ice. It
is getting from that to the parts that is the task. Bolting
the parts together is trivial.

You need a seed which consists of a VN swarm. How big this seed is
depends on a number of things - see above.

You still have your head in the sand. A seed is of
no use whatsoever unless there are pre-processed
raw materials in a form that can be assembled into
a copy of the seed, and they don't exist.

Stanford and Cornell are doing a great job - don't get me wrong.

I agree, but the fact remains that there is a huge gap
between where they are now and what is needed to
manufacture anything using atomic scale methods.

You don't need atomic scale models.

Yes you do. Either that or large plant with multiple
stages to smelt and refine rubble into usable material
followed by a series of piece-part manufacturing
processes and finally assembly. Bacteria and enzymes
and other molecular processes are the only way to
extract minerals at low temperature.

You need macroscopic CAD/CAM. In
my book you are STILL macroscopic even if components are a few microns
across. See above. In fact atomic scale (a DVD on a sperm) is a
DISADVANTAGE. In fact Stanford's work is IKEA/B&Q sized.
My
only criticism is that Andrew Ng to take an eample is also qworking on
linguistics - writing some great papers by all account. However we
would move faster with a TOTALLY DEDICATED effort. I think people like
IKEA and B&Q should sponsor students. If I were a university teacher I
would feel the need to teach a balanced AI course. To be a teacher a
Spanish, just as every teacher is "a teacher of English".

And how would that help anyone smelt alumino-silicate
rock into aluminium scaffolding poles and solar cells?

You have to build a furnace using CAD/CAM.

Nonsense. Do you think the 19th century furnaces used
CAD/CAM? Do you _design_ one with CAD if you want but
it is the "M" part where the problem lies. No amount
of "CA" will help if you don't have a way to manipulate
the matter.

I think a solar furnace is
the solution that makes the least assumttions about technology,
although a genetically engineered organism can do mineral extraction.
In fact (as I think I said in a previous exchange with you) you can
get quite a lot of DNA by carrying on up the Amazon. You can certainly
get copper as a species of horseoe crab has copper based haemoglobin.
What Greek! Haemos is iron. Haemoglobin contains iron!

Exactly, and Haemoglobin contains a _single_atom_
of iron.

The
oder of magnitude of forces at L1 will be 5km/h. This is not an
enormous force. I talk in terms of speed since the strength required
has the dimensions of speed. I fact it need not be strong at all.

Rubbish, the typical CME has a mass of 10^9 tonne and is
moving at 500 km/s ! Your mass of 0.055 gsm is tissue
paper, fine for a small solar sail but in a non movable
configuration it wouldn't survive even the smallest CME. A
plate of hundreds of km diameter capable of surving a CME
would need to be hundreds of tonnes per km^2 and if 700 km
in diameter (I think you said 10% of the Earth diameter)
would be 35 million tonnes at 100 tonne/km^2 and more
likely to be a billion tones.

Does this matter if you have replication?

We don't.

Smelting that much aluminium out of asteroidal rock
is not going to be done by Sonic the Hedgehog, even
if he can use Javalink.

2, 4 8 etc. Sonics will.

No, no matter how many you have, they remain just
pixels on a screen with no ability to influence
real matter in any way. I think you have been
playing too many computer games and are losing the
distinction between them and real life. An infinite
number of Sonics couldn't band a paper clip.

George

On 10 Feb, 11:53, "George Dishman" wrote:
"Ian Parker" wrote in message
I think we are talking slighly at cross purposes. There is the L1
solution which may or may not be rigid and there is the MEO solution
which is definitely NOT rigid.

I have only been discussing the L1 approach which is
of necessity somewhat rigid. It could be a "springy"
sheet that can be deformed and return to shape but
it cannot be a simple foil or mesh which is spun.

Agreed

The earth orbiting solution would a Dyson Swarm but
that is a different topic entirely.

The dyson swarm (MEO) solution requires a lot more mass than L1. With
a replicator this will not matter.
In fact MEO would work rather like the
quadrantal rule for aircraft in VFR. One orbital plane would consist
of rigid structures a few km across and at constant spacing and
different orbital planes would be at different heights (they need
differ by only 100m or so).

No, you need multiple orbital inclinations like this

http://en.wikipedia.org/wiki/Imageyson_Swarm.GIF

This is no different to what I was thinking. You need the different
inclinations at different heights to avoid collisions.

or all you do is remove a thin line from the Sun. I have
seen a great web site a few years ago where a range of
swarms had been animated but I can't find it now.

My rotation in a year was an estimate of the rough magnitude of tidal
forces on an L1 Now you can have a structure at 55Kg/km^2 in tension
quite easily, ...

No you can't. Here is the lowest areal density material
I know of

http://www.space.com/businesstechnol...bonsail_000302....

Let me tell you a secret. 55kg/km is in fact not my figure. This topic
was discussed in sci.space.policy. Most oof the contributers had the
idea of transporting material from Earth using rockets. All the
material - not just chips and critical parts. If you say 55kg/km^2 is
unrealistic I am not going to argue with you - but it makes total
transportation from Earth unrealistic. If you have a machine of
exponential growth then weight does not matter in the same way. You
will go for MEO.
They have achieved 5 gsm, compared to 80 gsm for typical
office paper. That is 5000 kg/km^2 (5 tonne/km^2) so
55 kg/km^2 is two orders of magnitude less than credible.

Replication is not relevant, you are making thin panels
which have no capability to reproduce because that extra
function would increase the mass. Besides which, we do not
have self-replicating technology in any form, nor are we
going to have it in the timescales of the possible methane
problem.

It is not. A CAD/CAM based VN not only replicates it also makes
anything that is compliant.

2) A rigid strucure is not really needed.

The material above can be folded and will restore its shape
which is what is needed. You cannot use spin for an L1
solution because the sheet must stay perpendicular to the
Earth Sun line.

3) I think we have a little bit of confusion about 5km/h. It does not
matter how large a structure is. The important thing is the speed an
object attains in traversing it. If we build a brick wall 5m high at
10m/s^2 (10 = R&R 9.81) we have 10m/s or 18km/h.

Yes, and if your shield passes the Earth edge on it is 600km
"high". If the centre is in freefall, what is the gravity at
the top and bottom? What speed do you attain falling from the
centre to the bottom (the edge nearest the Earth)?

If you have the sunshield at L1 the answer id something like 5km/h. I
mentioned a year as being the critical time at L1. Forces there are
very small. Getting there? The assembly would be folded.

More importantly, with an areal density of 5 tonne/km^2, what
is the tension at the centre?

The important parameter is the free fall speed. At the center the
force is compressive.

A tiny fraction of the cost of building smelters and
manufacturing plant to process your asteroid in
orbit. The ISS would be nothing more than a
proof-of-concept prototype for your idea.

The return to the Moon is in fact proposing just that smelters. Ca you
build a smelter that is small?

You can, but at 5 tonne/km^2, a 700km diameter shield
has a mass of nearly 2 million tonne. Unless each
smelter load has a significant mass, the loading and
unloading times become dominant and even a large
number of smelters will be too slow. Before you go
off on a tangent about replication, forget it. Smelters
don't make more smelters, they just extract raw material.

I think we shold be clear about what we would be trying to achieve. A
VN system takes in raw material and replicates. The replication is
complete. If we have smelters we produce more smelters. As I said I
should have talked about VN swarms rather than VN machines. Each
entity in a swarm and a smelter is an entity is produced by other
entities. A swarm is a VN swarm if the inputs left after subtracting
outputs from other elements are basic inputs.

In fact industry on Earth is a kind of VN swarm. We have industry
where basic raw materials form products. We have all the machines
needed to produce the machines. If we have a flatpack assembler a
closed loop (potentially) exists on Earth.

If you are talking about building a
sunshield you can have small pieces (even down to a cm^2) and small
tools. If you are talking about high temperature processes there is a
minimum size required. For low temperature processes you cut the
sizeProbably the best answer within current technological capabilities
is to heat by directing sunlight onto the furnace.

Again, that is all sci-fi wishful thinking, we don't
have low temperature processes for separating rocks
into their constituent element and we aren't going
to have them any time in the next couple of decades.

Why do you need low temperature processes. I will accept that seed
sizes can be reduced for a pure low temperature route. But even if the
seed is 100 tons or so that is still within current lift capability.
As I have explained nanotechnology is suspect because we want to build
any CAD/CAM object which is compliant, but it is useful for certain
processes. Clearly the further we can minaturize the basic seed the
lower will be the launch cost. Of corse because of thermal
considerations a high temperature process has an intrinsic size.
Throughout the years the size of electronic components has steadily
gone down,

Yes, but the temperature needed to grow a silicon
crystal hasn't changed.

True. Initially a few critical components would come from Earth. This
would be reduced as time went on.

but we have a long way to go to DNA where a sperm contains
4GB (a DVD).

A far lower sum
would bring capabilities up. You are right though to focus on the low
level of achievment of NASA.

I never mentioned them, you keep ranting on about
them. I'm not interested in your political ravings.

I think it iss fair comment.

Given that you need a space-based manufacturing plant
capable of processing millions of tonnes of material
in just a few years, the ISS pales into insignificance.
It is a tiny proof-of-concept demonstrator, and cost
efficiencies on your vastly larger plant would be even
worse. It is unlikely it could survive in low orbit and
probably construction at an Earth moon Lagrange point
or farther away would be essential to avoid tidal force
problems.

The ISS is being built by transport from Earth. This is a totally
different concept.
...

Sure, we can calculate all sorts of complex stuff, but
a calculation never repaired a toaster, you need the
ability to manipulate material before any of that is
of any use.

Lets reduce this to its basics. NASA in its heady days was proposing
space colonies where the standard flatpack assembler was called an
astronaut. In discussing complex equations I was merely looking at
what you would need to replicate an astronauts assembing capabilities.
My claim is that the problem is not that complicated and can be solved
by basic analytical techniques.


You still have your head in the sand. A seed is of
no use whatsoever unless there are pre-processed
raw materials in a form that can be assembled into
a copy of the seed, and they don't exist.

What about all the extractive technology here on Earth. It is an
example of an extracting and replicating system? I will however
concede one point. If we could substitute LOW temperature processes
for high temperature ones extractive industry would be made much more
efficient. This is so both in Space and on Earth. Rio Tinto and other
mining companies should be "carrying on up the Amazon". "Carry on up
the Amazon" is of course a crude statement. It implies that we are
simply gathering DNA and splicing large strands into our organism. In
the future (I am not stipulating this as essential for the basic
project) we will be able to produce a sequence theoretically and make
it in a gene sequencer.
Stanford and Cornell are doing a great job - don't get me wrong.

I agree, but the fact remains that there is a huge gap
between where they are now and what is needed to
manufacture anything using atomic scale methods.

You don't need atomic scale models.

Yes you do. Either that or large plant with multiple
stages to smelt and refine rubble into usable material
followed by a series of piece-part manufacturing
processes and finally assembly. Bacteria and enzymes
and other molecular processes are the only way to
extract minerals at low temperature.

It is better, I will concede but NOT essential.


You have to build a furnace using CAD/CAM.

Nonsense. Do you think the 19th century furnaces used
CAD/CAM? Do you _design_ one with CAD if you want but
it is the "M" part where the problem lies. No amount
of "CA" will help if you don't have a way to manipulate
the matter.

Yes but we don't use 19th century furnaces today.


Does this matter if you have replication?

We don't.

I know, they is the key step that has to be taken.

Smelting that much aluminium out of asteroidal rock
is not going to be done by Sonic the Hedgehog, even
if he can use Javalink.

2, 4 8 etc. Sonics will.

No, no matter how many you have, they remain just
pixels on a screen with no ability to influence
real matter in any way. I think you have been
playing too many computer games and are losing the
distinction between them and real life. An infinite
number of Sonics couldn't band a paper clip.

The interesting thing obout Sonic and about games is that the Pentagon
is proposing to base the latest generation of its ground automation
weapons on AI ideas pioneered by games. This is interesting from a
number of viewpoints. During the Cold War military science was at the
cutting edge. Now games seem to be.


- Ian Parker

In article ,
"George Dishman" wrote:

"Ian Parker" wrote in message
oups.com...

snip

In fact (as I think I said in a previous exchange with you) you can
get quite a lot of DNA by carrying on up the Amazon. You can certainly
get copper as a species of horseoe crab has copper based haemoglobin.
What Greek! Haemos is iron. Haemoglobin contains iron!

Exactly, and Haemoglobin contains a _single_atom_
of iron.

Human haemoglobin comprises four similar protein subunits, each
containing a heme group with its iron atom, so in all it has four iron
atoms. You may be thinking of the smaller, related protein myoglobin,
which is not divisible into subunits and contains a single heme group.

And JFTR the Greek word _haima_ means "blood"; "iron" is _sideros_. The
two roots are found together in the medical term "haemosiderin", which
refers to granular iron-rich substances deposited in body tissues due to
certain metabolic abnormalities. A "siderite" is a meteorite containing
a large proportion of iron; "siderite" is also the geological name for
ferrous carbonate.

BTW some have connected the Greek _sideros_ with the Latin _sidus_,
"star", from which we get "sidereal", as an allusion to meteorites as an
early source of iron -- indeed, native iron (that doesn't require
smelting from ores) is pretty well unknown otherwise. But AFAIK
historical linguists now consider this association to be spurious, a
case of "false friends".

--
Odysseus

On 10 Feb, 22:26, Odysseus wrote:
And JFTR the Greek word _haima_ means "blood"; "iron" is _sideros_. The
two roots are found together in the medical term "haemosiderin", which
refers to granular iron-rich substances deposited in body tissues due to
certain metabolic abnormalities. A "siderite" is a meteorite containing
a large proportion of iron; "siderite" is also the geological name for
ferrous carbonate.

BTW some have connected the Greek _sideros_ with the Latin _sidus_,
"star", from which we get "sidereal", as an allusion to meteorites as an
early source of iron -- indeed, native iron (that doesn't require
smelting from ores) is pretty well unknown otherwise. But AFAIK
historical linguists now consider this association to be spurious, a
case of "false friends".

Good point! You find reactive metals - like Iron in their elemental
state. You might not need reduction!

"Ian Parker" wrote in message oups.com...
On 10 Feb, 22:26, Odysseus wrote:
And JFTR the Greek word _haima_ means "blood"; "iron" is _sideros_. The
two roots are found together in the medical term "haemosiderin", which
refers to granular iron-rich substances deposited in body tissues due to
certain metabolic abnormalities. A "siderite" is a meteorite containing
a large proportion of iron; "siderite" is also the geological name for
ferrous carbonate.

BTW some have connected the Greek _sideros_ with the Latin _sidus_,
"star", from which we get "sidereal", as an allusion to meteorites as an
early source of iron -- indeed, native iron (that doesn't require
smelting from ores) is pretty well unknown otherwise. But AFAIK
historical linguists now consider this association to be spurious, a
case of "false friends".

Good point! You find reactive metals - like Iron in their elemental
state. You might not need reduction!


How sanguine...