Crossposted from the New Center for Amateur Future Studies
Nuclear powered nano-robots that could replace food forever.
Via Brian Wang and Michael Anissimov
Animals eat things. It’s just a part of what makes us animals, and we’re usually too hungry to ponder why we do it. Humans, cows, butterflies, rodents, lizards and all other critters consume organisms to retrieve energy. The process is called metabolism, and it’s what our bodies do to keep us alive.
It all starts when a person (say, me) bites into a delicious red tomato. First, the tomato is masticated – chewed – to make it easy to pass through my esophagus (the food tube) and into my stomach, where it gets disintegrated by some very potent natural acids. What remains of the tomato is a bubbly stew of basic organic materials like valine and fructose. The next step for that nutrient soup is a journey through my intestines, where thousands of little receptors are waiting to bond with nutrients as they pass through – in fact, I think one just snagged some valine from that chicken soup I had for lunch. Those receptors then transport the nutrients into my bloodstream where my cells can use them. Now... I’m ready to metabolize.
This is a diagram of valine, an essential amino acid contained in poultry and vegetable proteins. Each little sphere on the model is an individual atom, so metabolism is an extremely small-scale endeavor.
Now, a few hours after eating the tomato, I have some nutrients floating around in my bloodstream, and it’s up to my trusty circulatory system to deliver them to my various cells. My cells then pull in the nutrients from my blood and promptly begin shredding them up. The cells have little tools called mitochondria, which disassemble the carbohydrates, amino acids, and fats I have eaten and use them to create energy in the form of adenosine triphosphate (ATP). Each individual enzyme of ATP is like a tiny organic battery, storing up energy for later use.
I am using the energy of ATP to type this post. When I decide to move my hands and fingers over the keyboard, my brain sends tiny electric pulses along my nerve cells. When those pulses reach the appropriate muscles, they give the muscle cells a little zap, signaling them to activate. The muscle cells then break apart some of the ATP they have stored, and release its energy in the form of heat. That heat then causes the appropriate muscles to expand or contract and move my fingers, with enough precision that I can easily press down the period key on my keyboard. -– like that
So, what does all this have to with that link about nanotech at the beginning?
Robert Freitas at the Institute for Molecular Manufacturing has devised an alternative to natural metabolism. Tiny nano-robots (we’re dimensions of about a billionth of meter) could use long lasting nuclear energy to replace our need for food. Each bot would have a power core of slowly decaying gadolinium-148, which has a half-life of about 75 years. Dense elements like gadolinium can contain huge amounts of energy when destabilized like the gadolinium-148 isotope. The robots would be programmed to use the radioactive decay materials from their power core to interact with our natural cell processes and artificially generate enough ATP to power our bodies.
Freitas’ ingenious but speculative design for artificial ATP generation by nanobots.
With this speculative design, we could inject a few milliliters of these robots into our blood and have enough energy to function normally for decades. The technological advancement and mass production of advanced nanotechnology has the potential to end hunger for humanity. The real excitement here is how well the physical principles behind nanotechnology are. With the right advancements in engineering and molecular manufacturing these devices could become a reality. Nanotech could be a huge boon to early transhumans, allowing significant physical freedom while they wait for a greater scientific understanding of the brain to allow fully artificial bodies, or mind uploading.