Could Fullmetal Alchemist's alchemy work in real life?

Ed claps, touches the ground, and one second later there’s a wall. Every time I see it, the same dumb question pops up: how much would that actually cost? Not “is it magic”, but how many joules, how many seconds and what machine you’d need.

I ran the numbers with real physics, one source at a time, and ran into something I didn’t expect: physics almost never objects to the what. Walls, diamond, steel, even gold: all of that exists and gets made. The problem is the how long. Doing it in one second takes a power and a heat that would destroy both the object and the alchemist. And where alchemy fails in the story, it fails in physics too.

Before bringing in physics, we need to pin down what the story actually claims. I only use Hiromu Arakawa’s manga and Fullmetal Alchemist: Brotherhood; the 2003 anime changes important rules and I keep it separate.

• Three stages: comprehension, deconstruction and reconstruction of matter. That’s the definition Brotherhood opens with.
• The Law of Equivalent Exchange, split in two: conservation of mass (as much mass comes out as goes in) and the Law of Natural Providence (the product has the same nature as the material: you can’t get stone out of water).
• Transmutation circle: a conduit that focuses the flow of energy. People who’ve seen the Gate use their own body as the circle and clap.
• Taboos: making gold (ch. 3) and human transmutation, which never works.
• Energy: the official version says it comes from tectonic movement.

What the story never says is how each stage works: what force breaks the bonds, how the atoms get placed or how much energy it takes. Arakawa warns in volume 1 that her alchemy has nothing to do with the real thing. That gap is exactly what I want to fill.

♣ Lost? Lesson: Can you make something from nothing? Conservation, no fear

The story’s law looks a lot like real laws, but it only covers part of them:

It’s a mass balance, not an energy or entropy balance. And thank goodness: if an alchemist could create mass from nothing, they’d have to pay E = mc². One gram is 9×10¹³ joules, about 21.5 kilotons of TNT. An alchemist without equivalent exchange would be a walking nuclear weapon. The law isn’t a plot ornament: it’s what keeps that world in one piece.

♣ Lost? Lesson: Why doesn't diamond turn into graphite?

Of the three stages, the first two happen inside the circle and you can’t see them: comprehension (knowing what you have and what you want) and deconstruction (breaking the material down). The third, recomposition, is the flash and the rising wall. It’s the one you see on screen, and the one with the most explaining to do.

If you ask that third phase to follow physics, recomposition has three costs, and the story only shows the first:

1. Energy to form the new structure. Sometimes it’s negative: forming chemical bonds releases energy.
2. Information: knowing where each piece goes and applying it. That’s the circle’s job.
3. Heat. Every irreversible placement step dissipates energy. The second law of thermodynamics doesn’t let you put matter in order for free: since Landauer (1961) we’ve known that even erasing one bit of information has a minimum cost in heat.

♣ Lost? Lesson: Joules, watts or calories? Energy and power without fear

♣ Lost? Lesson: How much is 7×10²⁷? Huge numbers without fear

This is the core of the post, and I’ll explain it with the most extreme case: assembling a human body atom by atom.

One electronvolt per atom is a ridiculously small amount, but there are 7×10²⁷ atoms. Here’s that heat, depending on how long you take to release it:

The energy is the same in all three rows. What changes is the power: energy divided by time. And here’s the beautiful part: biology already solved the recomposition of a human being, and it solved it by taking nine months.

Try it yourself: pick what to build and how long to give it.

Not everything costs the same. The story’s creations can be ranked by how much has to be broken and how much has to be known to rebuild them, and all three costs grow with the level:

♣ Lost? Lesson: Joules, watts or calories? Energy and power without fear

It’s the most common creation in the story and the easiest to defend. The material doesn’t change: it gets moved, compacted and welded together. That takes three steps: bring the earth into the new shape, compact it to squeeze out the gaps, and join the grains so it’s solid. Joining them means sintering (heating until the grains weld together) or cementing.

With Ed’s wall, made of granite and 3 × 2 × 0.3 m:

Moving earth is cheap: lifting the wall one metre costs 47 kJ, a small car engine’s power for one second. The expensive part is turning earth into rock. Sintering all of it takes 5.8 GJ, and in one second that’s 5.8 GW: several nuclear reactors for one wall. The realistic design is different: weld only a 2 cm skin and compact the inside. The cost drops to ~1 GJ, and the wall comes out steaming, hundreds of degrees hot.

The story almost never shows two details. The first is the hole: because mass is conserved, the wall comes from somewhere, and in front of it or under it there’s a 1.8 m³ hole. The second is that compacted earth isn’t granite: without sintering or cementing, it holds far less than it looks like it would.

The closest thing today

It isn’t regular 3D printing, which goes layer by layer. The closest thing to a transmutation circle is making the whole volume at once:

• Volumetric printing. It projects light from many angles onto a spinning resin, and the accumulated dose cures the whole object at once: centimetre-sized parts in 30–120 seconds, with 0.3 mm detail (Kelly et al., 2019). A later version gets under 30 seconds (Loterie et al., 2020).
• Acoustic holograms. A 3D-printed plate shapes an ultrasound field that pushes particles, gels or cells into place, without touching them and in a single step (Melde et al., 2016 and 2023). It’s a flat pattern that, once powered, places matter in 3D. All it lacks is scale: it moves particles, not walls.
• Solar sintering. ESA and DLR concentrated sunlight with 147 mirrors to melt simulated moon dust: a 20 × 10 × 3 cm brick in about 5 hours.

Verdict: ✓ possible with engineering, in minutes rather than one second, and with a wall that burns.

♣ Lost? Lesson: What is a wall made of? Atoms and elements without fear

♣ Lost? Lesson: Why doesn't diamond turn into graphite?

Here alchemy changes the chemistry: the same atoms, in another compound or another structure. The story has three cases that cover the three possible situations, and they’re easier to understand if you draw the energy along the reaction:

Downhill: Greed and Ed. Greed hardens his skin by rearranging carbon into diamond, and Ed works out that it’s carbon and that its structure decides whether it’s diamond or graphite (ep. 13). At room temperature graphite is the stable one: going from diamond to graphite releases 2.9 kJ/mol. Diamond survives because there’s a barrier; in a vacuum it only turns into graphite at 1500–1800 °C. Ed gets the cheap part: pushing the carbon over the barrier so it falls on its own. Greed gets the expensive part: holding about 6 kg of carbon in a state that today is made at high pressure or atom by atom. Growing a 1 mm shield by vapour deposition would take about 10 hours.

Uphill: the steel spear. The iron in the ground is oxidised, and reducing it to metal costs at least 4.9–7.4 MJ per kilo of iron: 10–15 MJ for a 2 kg spear. A real blast furnace uses about 48 MJ for that spear. You also have to gather the iron: the crust is 3.9 % iron, so it takes about 51 kg of earth for every 2 kg of iron. The cost is in breaking the iron–oxygen bonds, not in ordering the atoms.

Up to come down: Mustang. In his fight with Lust (ch. 38; ep. 19), Mustang splits the water in the room into hydrogen and oxygen and lights it. Splitting water costs 285.83 kJ/mol, and the flame gives back exactly the same: the balance is zero. Mustang uses alchemy to charge a chemical battery with the room’s water and discharge it all at once. He doesn’t gain energy; he gains power, because the discharge lasts milliseconds.

Verdict: ~ plausible if chemical assemblers working in massive parallel ever exist. Today only biology works that way.

♣ Lost? Lesson: What is a wall made of? Atoms and elements without fear

In chapter 3 of the manga, Ed turns mine waste into gold bars to con a corrupt official, then turns them back into rocks (Brotherhood doesn’t adapt the scene). Changing an element means changing the number of protons in the nucleus. It’s possible, and it’s been done since 1919; what you can’t do is use chemistry for it. To see what it costs, you need the most important curve in nuclear physics:

From lead, gold isn’t downhill: 3 protons and 8 neutrons have to be torn off, and that costs 77 MeV per atom. An ounce of gold is 1.2×10¹² J, about 0.28 kilotonnes of TNT.

The fun detail is that coal-mine waste contains carbon, and building gold out of carbon would release energy, about 46 MeV per atom. It doesn’t happen because nuclei repel each other electrically, and the repulsion grows with every proton. Not even stars make gold that way: they do it by capturing neutrons very fast, in events like the neutron-star merger observed in 2017.

What has actually been achieved: the ALICE experiment at the LHC saw about 89,000 gold nuclei form per second in lead collisions. Over a whole four-year run they added up to 2.9×10⁻¹¹ grams, and they break apart almost immediately. There’s a proposal, not yet peer reviewed, to produce gold in fusion reactors: about 2 tonnes a year per thermal gigawatt, in a reactor that doesn’t exist yet, and the gold would come out radioactive for about 14 years.

Verdict: ~ possible, but in another energy league, and with radioactive waste the story never shows.

The story’s most famous scene is the ingredient list for a human body, which according to Ed you could buy with a kid’s pocket money. Here it is next to the ICRP’s 70 kg “reference man”:

The list is nearly right: the right elements in the right order of magnitude. That’s what makes it interesting, because it shows the ingredients aren’t the problem. The problem is order, information and time.

Nature has its own transmutation circle: the ribosome. It reads a template (messenger RNA) and assembles matter (amino acids) into a specific shape (a protein).

A bacterial ribosome chains 12–21 amino acids per second, and an animal one 4–5. Making the ~11 kg of protein in a body in one second would take about 3×10²⁴ ribosomes working at once. Biology spreads it over nine months, across trillions of cells, with the heat carried away by the mother’s blood. That’s why it comes out at ~48 W.

And even with all that, human transmutation would fail for three reasons:

1. The recipe isn’t the person. With the list and a genome you could, in theory, build a human body. Not Ed and Al’s mother: that takes that person’s information (her neural connections, her memories), and that information was lost when she died.
2. Building it in one second destroys it. That’s the heat table above.
3. A body isn’t an object. It’s alive because it keeps up a constant flow of energy. Assembling the parts doesn’t start the metabolism, just as assembling an engine doesn’t switch it on.

The story fits all three: what the Elrics create isn’t their mother.

Verdict: ✕ impossible.

♣ Lost? Lesson: Joules, watts or calories? Energy and power without fear

The official explanation is energy from tectonic movement. The real Earth has something similar: its internal heat leaks out of the surface at about 92 milliwatts per square meter (Davies and Davies, Solid Earth, 2010). A one-square-meter circle would need six days to gather what it takes to lift Ed’s wall, and about 2,000 years to sinter it. For one ounce of gold, 400,000 years.

So the official version can’t work. You need a store: energy collected over a long time and released all at once. And here’s the lovely part. The story’s reveal is that Amestris’s alchemists are unknowingly drawing on a Philosopher’s Stone hidden under the whole country, made from the souls of an entire city. The plot twist matches what physics demands: a giant battery under everyone’s feet. The story turns a physical limit into the moral engine of the plot.

♣ Lost? Lesson: How much is 7×10²⁷? Huge numbers without fear

Putting the four levels together, this is the distance between the story and the best demonstrated technology. The fusion proposal is hatched because that reactor doesn’t exist:

Volumetric printing is just two orders of magnitude away from the story: it’s the closest thing to a transmutation circle that exists. At the other end, an ounce of gold at the LHC’s rate would take hundreds of times the age of the universe.

• “It costs so many joules, so it’s impossible.” The total energy is usually manageable; what makes it impossible is dividing it by the one second the scene lasts. Always look at the power.
• “Creating always costs energy.” Forming bonds releases heat, and that heat has to go somewhere too. From carbon to gold, even nuclear physics would come out ahead if it weren’t for electric repulsion.
• “A nanobot places a million atoms per second.” That’s a theoretical projection by Drexler from 1992, not a measurement. What’s been demonstrated by 2026 is dozens of carbon atoms placed one by one at 4 K (−269 °C) in a vacuum. In 1990, IBM took about 22 hours to write its logo with 35 atoms.

Putting it all together, FMA’s alchemy can be described as programmable matter powered by an energy store. With that model, almost every rule in the story falls out on its own. That leaves three licences no known physics hands out for free:

1. An energy store of nuclear density that discharges on demand. The story pays for it: the Stone costs souls.
2. A field that can place matter at atomic scale throughout a volume. Today it exists at the micron scale (sound) and in resins (light).
3. An almost unlimited heat sink. The story never mentions it, and it’s what would make the speed believable.

If you keep one idea, make it this one: always separate what gets made (almost always chemically possible) from how long it takes (almost always impossible). The story gets the first right and allows itself the second.

And one more thing stays with me: Arakawa warns that her alchemy has nothing to do with the real thing, and then builds a system that respects conservation of mass and of elements, needs an energy store (and makes it the center of the plot) and fails exactly where physics says it should. For “not science”, it’s better physics than plenty of films that brag about being scientific.