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Molecular Nanotechnologywww.zyvex.com/nano
Ralph C. MerklePrincipal Fellow, Zyvex
www.merkle.com
Nick Smith, ChairmanHouse Subcommittee on Basic Research
June 22, 1999
In Fiscal Year 1999, the federal government will spend approximately $230 million on nanotechnology research.
National Nanotechnology Initiative
Announced by Clinton at Caltech Interagency (AFOSR, ARO, BMDO, DARPA,
DOC, DOE, NASA, NIH, NIST, NSF, ONR, and NRL)
FY 2001: $497 million
http://www.whitehouse.gov/WH/New/html/20000121_4.html
Academic and Industry
Caltech’s MSC (1999 Feynman Prize), Rice CNST (Smalley), USC Lab for Molecular Robotics, etc
Private nonprofit (Foresight, IMM) Private for profit (IBM, Zyvex) And many more….
There is a growing sense in the
scientific and technical community that we are about to enter a golden new era.
Richard Smalley
1996 Nobel Prize, Chemistry
http://www.house.gov/science/smalley_062299.htm
The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom.It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big.
Richard Feynman, 1959
http://www.zyvex.com/nanotech/feynman.html
The book that laid out the technical argument for molecular nanotechnology:
Nanosystemsby K. Eric Drexler, Wiley 1992
Three historical trendsin manufacturing
More flexible More precise Less expensive
The limit of these trends: nanotechnology
Fabricate most structures consistent with physical law
Get essentially every atom in the right place
Inexpensive (~10-50 cents/kilogram)
http://www.zyvex.com/nano
Coal Sand Dirt, water
and air
Diamonds Computer chips Grass
It matters how atomsare arranged
Today’s manufacturing methods move atoms in
statistical herds Casting Grinding Welding Sintering Lithography
Possible arrangements of
atoms.
What we can make today(not to scale)
The goal: a healthy bite.
.
Core molecularmanufacturingcapabilities
Today ProductsProducts
Products
Products
Products
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ProductsProducts
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Overview of the development of molecular nanotechnology
Terminological caution
“Nanotechnology” has been applied to almost any research where some dimension is less than a micron (1,000 nanometers) in size.
Example: sub-micron optical lithography
Two morefundamental ideas
Self replication (for low cost) Positional assembly (so
molecular parts go where we want them to go)
Von Neumann architecture for a self replicating system
UniversalComputer
UniversalConstructor
http://www.zyvex.com/nanotech/vonNeumann.html
Drexler’s architecture for an assembler
Molecularcomputer
Molecularconstructor
Positional device Tip chemistry
Illustration of an assembler
http://www.foresight.org/UTF/Unbound_LBW/chapt_6.html
The theoretical concept of machine duplication is well developed. There are several alternative strategies by which machine self-replication can be carried out in a practical engineering setting.
Advanced Automation for Space MissionsProceedings of the 1980 NASA/ASEE Summer Study
http://www.zyvex.com/nanotech/selfRepNASA.html
A C program that prints out an exact copy of itself
main(){char q=34, n=10,*a="main() {char q=34,n=10,*a=%c%s%c; printf(a,q,a,q,n);}%c";printf(a,q,a,q,n);}
For more information, see the Recursion Theorem:http://www.zyvex.com/nanotech/selfRep.html
English translation:
Print the following statement twice, the second time in quotes:“Print the following statement twice, the second time in quotes:”
C program 800Von Neumann's universal constructor 500,000Internet worm (Robert Morris, Jr., 1988) 500,000Mycoplasma capricolum 1,600,000E. Coli 9,278,442Drexler's assembler 100,000,000Human 6,400,000,000NASA Lunar
Manufacturing Facility over 100,000,000,000http://www.zyvex.com/nanotech/selfRep.html
Complexity of self replicating systems (bits)
How cheap?
Potatoes, lumber, wheat and other agricultural products are examples of products made using a self replicating manufacturing base. Costs of roughly a dollar per pound are common.
Molecular manufacturing will make almost any product for a dollar per pound or less, independent of complexity. (Design costs, licensing costs, etc. not included)
How long?
The scientifically correct answer is: I don’t know
Trends in computer hardware suggest the 2010 to 2020 time frame
Of course, how long it takes depends on what we do
Developmental pathways
Scanning probe microscopy Self assembly Progressively smaller positional
assembly Hybrid approaches
Moving molecules with an SPM(Gimzewski et al.)
http://www.zurich.ibm.com/News/Molecule/
Self assembled DNA octahedron(Seeman)
http://seemanlab4.chem.nyu.edu/nano-oct.html
DNA on an SPM tip(Lee et al.)
http://stm2.nrl.navy.mil/1994scie/1994scie.html
Buckytubes(Tough, well defined)
Buckytube glued to SPM tip(Dai et al.)
http://cnst.rice.edu/TIPS_rev.htm
Building the tools to build the tools
Directly manufacturing a diamondoid assembler using existing techniques appears very difficult .
We’ll have to build intermediate systems able to build better systems able to build diamondoid assemblers.
If we can make whatever we want
what do we want to make?
Diamond Physical PropertiesProperty Diamond’s value Comments
Chemical reactivity Extremely lowHardness (kg/mm2) 9000 CBN: 4500 SiC: 4000Thermal conductivity (W/cm-K) 20 Ag: 4.3 Cu: 4.0Tensile strength (pascals) 3.5 x 109 (natural) 1011 (theoretical)Compressive strength (pascals) 1011 (natural) 5 x 1011
(theoretical)Band gap (ev) 5.5 Si: 1.1 GaAs: 1.4Resistivity (W-cm) 1016 (natural)Density (gm/cm3) 3.51Thermal Expansion Coeff (K-1) 0.8 x 10-6 SiO2: 0.5 x 10-6Refractive index 2.41 @ 590 nm Glass: 1.4 - 1.8Coeff. of Friction 0.05 (dry) Teflon: 0.05
Source: Crystallume
Strength of diamond
Diamond has a strength-to-weight ratio over 50 times that of steel or aluminium alloy
Structural (load bearing) mass can be reduced by about this factor
When combined with reduced cost, this will have a major impact on aerospace applications
A hydrocarbon bearing
http://www.zyvex.com/nanotech/bearingProof.html
Neon pump
A planetary gear
http://www.zyvex.com/nanotech/gearAndCasing.html
A proposal for a molecular positional device
Classical uncertainty
kTkb2
σ: mean positional error k: restoring forcekb: Boltzmann’s constantT: temperature
A numerical example of classical uncertainty
kTkb2
σ: 0.02 nm (0.2 Å) k: 10 N/mkb: 1.38 x 10-23 J/KT: 300 K
Born-Oppenheimer approximation
A carbon nucleus is more than 20,000 times as massive as an electron, so it will move much more slowly
Assume the atoms (nuclei) are fixed and unmoving, and then compute the electronic wave function
If the positions of the atoms are given by r1, r2, .... rN then the energy of the system is: E(r1, r2, .... rN)
This is fundamental to molecular mechanics
Quantum positional uncertainty in the ground state
σ2: positional variance k: restoring forcem: mass of particleħ: Planck’s constant divided by 2π
km22
Quantum uncertainty in position
C-C spring constant: k~440 N/m Typical C-C bond length: 0.154
nm σ for C in single C-C bond: 0.004 nm σ for electron (same k): 0.051
nm
Molecular mechanics
Nuclei are point masses Electrons are in the ground state The energy of the system is fully
determined by the nuclear positions Directly approximate the energy from the
nuclear positions, and we don’t even have to compute the electronic structure
Example: H2
Internuclear distance
En
erg
y
Molecular mechanics
Internuclear distance for bonds Angle (as in H2O)
Torsion (rotation about a bond, C2H6
Internuclear distance for van der Waals Spring constants for all of the above More terms used in many models Quite accurate in domain of
parameterization
Molecular tools
Today, we make things at the molecular scale by stirring together molecular parts and cleverly arranging things so they spontaneously go somewhere useful.
In the future, we’ll have molecular “hands” that will let us put molecular parts exactly where we want them, vastly increasing the range of molecular structures that we can build.
Synthesis of diamond today:diamond CVD
Carbon: methane (ethane, acetylene...)
Hydrogen: H2
Add energy, producing CH3, H, etc.
Growth of a diamond film.
The right chemistry, but little control over the site of reactions or exactly what is synthesized.
A hydrogen abstraction tool
http://www.zyvex.com/nanotech/Habs/Habs.html
Some other molecular tools
A synthetic strategy for the synthesis of diamondoid structures
Positional assembly (6 degrees of freedom)
Highly reactive compounds (radicals, carbenes, etc)
Inert environment (vacuum, noble gas) to eliminate side reactions
The impact of nanotechnologydepends on what’s being
made Computers, memory, displays Space Exploration Medicine Military Environment, Energy, etc.
Powerful computers
In the future we’ll pack more computing power into a sugar cube than the sum total of all the computer power that exists in the world today
We’ll be able to store more than 1021 bits in the same volume
Or more than a billion Pentiums operating in parallel
Powerful enough to run Windows 2015
Memory probe
Displays
Molecular machines smaller than a wavelength of light will let us build holographic displays that reconstruct the entire wave front of a light wave
It will be like looking through a window into another world
Covering walls, ceilings and floor would immerse us in another reality
Space
Launch vehicle structural mass will be reduced by about a factor of 50
Cost per pound for that structural mass will be under a dollar
Which will reduce the cost to low earth orbit by a factor 1,000 or more
http://science.nas.nasa.gov/Groups/Nanotechnology/publications/1997/
applications/
It costs less to launch less
Light weight computers and sensors will reduce total payload mass for the same functionality
Recycling of waste will reduce payload mass, particularly for long flights and permanent facilities (space stations, colonies)
Swallowing the surgeon
...it would be interesting in surgery if you could swallow the surgeon. You put the mechanical surgeon inside the blood vessel and it goes into the heart and “looks” around. ... Other small machines might be permanently incorporated in the body to assist some inadequately-functioning organ.
Richard P. Feynman, 1959 Nobel Prize for Physics, 1965
Nanomedicine Volume I
By Robert Freitas Surveys medical applications of
nanotechnology Extensive technical analysis Volume I (of three) published in 1999 http://www.foresight.org/Nanomedicine
Mitochondrion
20 nm scale bar Ribosom
e
Molecular computer(4-bit) +
peripherals
Molecular bearing
“Typical” cell
Mitochondrion
Molecular computer + peripherals
Disease and illness are caused largely by damage at the molecular and cellular level
Today’s surgical tools are huge
and imprecise in comparison
http://www.foresight.org/Nanomedicine
In the future, we will have fleets of surgical tools that are molecular both in size and precision.
We will also have computers that are much smaller than a single cell with which to guide these tools.
Medical applications
Killing cancer cells, bacteria Removing blockages Providing oxygen (artificial red
blood cell) Adjusting other metabolites
A revolution in medicine
Today, loss of cell function results in cellular deterioration:
function must be preserved With medical nanodevices, passive structures
can be repaired. Cell function can be restored provided cell structure can be inferred:
structure must be preserved
Cryonics37º C 37º C
-196º C (77 Kelvins)
Freeze Restoreto health
Time
Tem
pera
ture
(many decades)
Clinical trialsto evaluate cryonics
Select N subjects Freeze them Wait 100 years See if the medical technology of 2100 can
indeed revive them
But what do we tell those who don’t expect to live long enough to see the results?
Would you rather join:The control group?
(no action required)
orThe experimental group?
(see www.alcor.org for info)
Military applications of molecular manufacturing have even greater potential than nuclear weapons to radically change the balance of power.
Admiral David E. Jeremiah, USN (Ret)Former Vice Chairman, Joint Chiefs of StaffNovember 9, 1995
http://www.zyvex.com/nanotech/nano4/jeremiahPaper.html
Human impact on the environment depends on
Population Living standards Technology
Restoring the environment with nanotechnology
Low cost greenhouse agriculture Low cost solar power Pollution free manufacturing The ultimate in recycling
Solar power and nanotechnology
The sunshine reaching the earth has almost 40,000 times more power than total world usage.
Nanotechnology will produce efficient, rugged solar cells and batteries at low cost.
Power costs will drop dramatically
Environmentally friendly manufacturing
Today’s manufacturing plants pollute because they use imprecise methods.
Nanotechnology is precise — it will produce only what it has been designed to produce.
An abundant source of carbon is the excess CO2 in the air
Nanotechnology offers ... possibilities for health, wealth, and capabilities beyond most past imaginings.
K. Eric Drexler
The best wayto predict the future
is to invent it.
Alan Kay