Making Room at the Bottom
Moore's law states that the amount of transistors that can fit onto a computer chip will double every 18–24 months. This trend has been the driving force of our economy for the past 60 years. Innovation grew exponentially as the transistors got smaller. But what happens when we get too small, say the size of an atom. Richard Feynman once said: “There is plenty of room down at the bottom.” But with the current trajectory of Moore’s law, it appears there is not much room after all.
Well this sounds daunting! The driving force of our economy is about to hit it’s limit! How will we move on when there is no more growth to stimulate the economy? Luckily there is something else on the horizon. Something that can have the same exponential trends and growth that was given to us by transistors. This something is Atomically Precise Manufacturing.
Atomically Precise Manufacturing (APM), is just what it sounds like; manufacturing with atomic precision. Our universe is made up of tiny building blocks analogous to Legos, called atoms, and just like Legos, these atoms come in different shapes and sizes and are used to form larger objects and systems. So if we can use Legos to build larger objects, who’s to say we can’t do the same with atoms? While the laws of physics make configuring atoms ourselves much harder than Legos, they don't deny the possibility of it entirely. I'm sure you can already think of the immense applications APM could have on society and we will get into that, but first lets get an idea of how it works.
Using Atoms like Legos
Moving atoms into a configuration of our liking is no easy task. Eric Drexler, an American engineer who has studied the theory behind APM extensively, lays out the requirements to achieve APM in his book Radical Abundance.
- Structural Stability: Bonds keeping the molecule together must be strong enough to keep it together.
- Motion Control: Must have control over the movement of atoms.
- Reaction Rate: Must have a low reaction barrier and must react in a sufficient amount of time.
- Irreversible Forward Reactions: The reaction must bring the product into a lower energy state to prevent it from reversing back into it’s reactants.
- Single Reaction Path: Must be able to prevent unwanted reactions
Drexler argues that the most effective way to achieve these requisites is to have a mix of self-assembly and stereotactic control.
Self-Assembly
Self-assembly is when atoms or molecules form specific bonds and configurations through Brownian motion (The random movement of particles). For example, when you mix hydrogen and oxygen at room temperature they naturally form into H2O, or water. A much more complex example would be you. Every part of you was made through a billion year process of advanced self-assembly. Atoms formed molecules that formed bigger molecules, all through the random motion of particles. This process allowed for the creation of DNA and proteins which helped create all living things.
Such a simple idea, yet it created all of life on earth and now it’s going to help our society advance to the next tier of innovation.
Self-assembly has been used by molecular biologist and chemical engineers to create synthetic molecules and compounds for a while now. This is a good proof of concept that we can use self-assembly in the process of creating artificially precise molecules. By using the specific properties of different molecules and atoms, we can mix substances to get a desired product. While self-assembly seems promising for APM it does have its limitations.
Because of the random movement of the particles, it is hard to make any complex structures. We can get substances to go in general areas and create simple products but nothing as complex as a gear or a full on machine. If we want to get one atom into a specific spot we need more control of it. This is where stereotactic control comes in.
Stereotactic control
Stereotactic control is the act of moving individual particles to desired locations. After using self-assembly to get our base materials and structures, we can then finish the job off with stereotactic control. Getting stereotactic control to work at the atomic level would be similar to how it works at our normal scale.
A lot of people view molecules as a gas like material, but they are more analogous to blocks of matter with properties such as shape, size, mass, stiffness, etc. In other words we should treat them like solid objects rather than fluid gases. What this means is that we can build machine parts such as gears and bearings at the atomic scale in the same way we build them at our scale, with raw materials (raw materials in this case being singular atoms). And just like how machines building cars would place specific parts into place, the same would go for atomic machines, putting specific atoms and molecules into place. These machines would have stereotactic control over the atoms.
Now I’m sure some of you noticed the problem in my thinking. We need complex machines to control atoms, but we need to be able to control atoms to get complex machines. It’s like the chicken and egg problem. Getting the first machines seems to be the issue. Well lucky for us, we might have a solution. Bigger machines.
Scanning Tunneling Microscope
First, to move atoms we need a way to see them. That's where the Scanning Tunneling Microscope comes in. The STM consist of a machine that generates electrons out of a very fine-point needle (one atom thick at the end) and a vacuum seal chamber with a sample in it. Through an effect called quantum tunneling, we are able to send electrons to the surface of the sample without actually making contact with it. The distance between the sample and the tip (which changes due to the bumps and grooves formed by the atoms), dramatically determines the current of electrons flowing. The tip travels over the bumps and grooves of the surface, measuring varying currents which is then used to determine the brightness of a pixel on a screen. Once all the currents are measured and pixels are accounted for, a full picture is formed with atomic resolution.
While originally used to see atoms, Zyvex labs has built a STM that can help manipulate them. Zyvex is a company which specializes in advancing the field of nanotechnology by making better materials, adhesives, and other things at the nanoscale. For the past few years they have been researching ways to achieve APM. By building their own STM and using the process of Hydrogen depassivation (the removal of an oxide layer from the surface of a metal), they have made incremental steps in manipulating singular atoms.
Using self-assembly, they send hydrogen particles onto a silicon sample, resulting in a layer of hydrogen one atom thick bonded onto the silicon surface. Then using the needle, they increase the voltage enough so that the energy hitting the surface breaks the bond. With precise control of the voltage they have been able to do this with just one hydrogen atom at a time. Then they send in another element (usually phosphorus) which fills in the gaps left by the depassivated hydrogen. They continue doing this layer by layer creating their own, simple, 3D structures at the atomic scale.
Now its clear they are not making complex machines like the ones in our factories today, but this is a step in the right direction to stereotactic control. As advances by companies like Zyvex are made in APM, we will start to see the revolutionary impacts of having control over atoms.
The Inverse Moore’s Law
So how do moving atoms like Legos solve the end of Moore’s law? Well one can imagine that once we reach atomic precision of atoms and molecules, we can start to scale up. Zyvex thinks we can do it at an exponential rate as seen in the diagram below.
As we get better at making complex machines at the atomic scale, we can go from creating objects of just a few atoms to objects containing millions of atoms, all precisely place. Just like transistor size, as we expand our manufacturing abilities we will see innovations in other fields grow at the same rate once again stimulating our economy. It doesn't stop at millimeters either. Drexler argues that once we scale up to the size of three dimensional micro blocks, we can use them as the raw materials for much larger products. Picture this,
There is a garage sized factory. On the far side there is a cabinet spanning the whole wall containing smaller sized cabinets. Next to the cabinet is a robotic arm pulling out car parts from the cabinets and using them to build a full fledged car. You wonder where these parts are coming from. Through the clear glass of the cabinets you get to see inside each box and you find what appears to be a smaller scaled version of the main factory, an arm with a cabinet containing smaller cabinets. You can extend this observation as you look at the smaller and smaller cabinets making out a Russian doll like apparatus but instead of dolls, its full of factories. You finally get to the smallest cabinets; the last doll. It is here you find the arm using micro blocks to form bigger parts to send them off to the subsequent factory.
These tiny micro blocks, all atomically precise, being sent through multiple layers of machinery until an entire, full-sized car is made. Not just a full-sized car, but a full-sized car in which every atom was specifically placed. This is the power of APM.
Atomically Precise Future
I hope you are beginning to see just how much APM can change society. Society is only as advanced as its materials and tools. We went from the stone age to the bronze age to the silicon age. APM is likely to be the last transition we have to make. APM will drastically improve the tools we use to make things allowing us more freedom in design than ever before.
Materials
Some early advantages we will see is the strength of materials. Materials we use every day like steel and fabrics are not nearly as strong as they could be because they have impurities. To us a steel rod looks like a pure steel rod, but zoom in closer and you will see the specks of dirt and other metals littered throughout the atomic structure weakening the bonds holding it together. Imagine if we could make a purely steel rod. Nothing but pure iron and carbon. This would exponentially increase the strength of steel and any other materials made with APM. That's why carbon nanotubes and graphene have gotten so much hype for their immense tensile strength. They are atomically precise with little to no impurities. Stronger materials would give us the ability to make safer and more efficient cars, buildings and pretty much anything else we desire. With stronger materials we could build more durable rockets that could better handle long-term space travel. We could make buildings that do little to nothing during the most intense earthquakes. Atomically precise materials allow us to level up as a society.
Medicine
If you couldn't guess by now, APM would have a huge impact on the medical field. The reactions that make our bodies run properly happen at the atomic scale and being able to create machines at the same precision as our DNA will open up a whole new world of treatment and prevention options. Imagine if instead of having to use chemo on a general area of your body, we could send a small amount of the drug specifically to the tumor allowing for the protection of the healthy cells around it. Its like using an assassin to kill the tumor rather than bombing the entire location its in.
With APM, theoretical designs for synthetic red blood cells that carry 100 times the oxygen could finally become practical. We could make these, and at a large scale, and send them through the body allowing for better blood flow and respiration.
Looking farther into the future, we can see the possibility of manufacturing nanorobots that travel through your body, find any problems, and fix them, without you even knowing. Like having a million little doctors inside your body at all times. There are many more applications APM could have in the medical world, which makes it easy to see why APM would revolutionize the medical field.
Energy
One of the biggest problems over the past few decades has been the rising amounts of CO2 building up in the atmosphere. A point Drexler emphasizes in his book is that the amount of energy needed to fix the carbon problem will be way too costly in both money and space to solve with the technology we currently have. We would need 30 terawatt-years of non-carbon-based energy (we only produce 3 terawatts a year) along with land equivalent to 1% the Sahara desert for solar panels. With APM, we can drastically reduce all these figures.
Atomic precision would allow us to make solar cells much more efficient by increasing their overall surface area and by creating materials that could contain the energy lost from heat at a much higher rate then today’s do. On top of this, we could make these panels much thinner and more flexible making them perfect for the top of houses and buildings. We get the benefits of an efficient clean energy source, along with the material and lower costs of production, to solve the CO2 build up.
Quality of Life
Looking at the more general impacts of APM we can see that quality of life will increase dramatically. We will have the ability to create anything we want out of atoms!
APM will give us increased access to virtually every resource. Instead of having to find raw materials in mines, or burn down jungles for wood, or dig into the ocean, we can just make them out of a few common elements in our atmosphere. This will drastically bring down the cost of almost every product, lifting many people out of poverty and into a better state of living. Political tension between countries will drastically decrease, especially in developing areas, as the need to fight over resources decreases to almost 0.
All of human struggles throughout history can be connected to a lack of resources. We will, for the first time, be living in a world were we don't have this struggle.
Final Thoughts
If this all sounds ultra-optimistic, its cause it is and I wouldn't bet on this happening in the next ten years or so. But you have to realize the gravity of what APM can accomplish.
We are building with the blocks that make up, not just us, but every single thing that exists in the universe. We are on our way to unlocking the full range of possible things that can be created along with the key to solving our diminishing resource problem. We will be living in a world where our tools and resources don't limit what we can make but rather our imagination.
