@Ian Clifton: Oooh! Interesting. I like the propaganda idea. :)

@Tino: Thanks for clearing up the Morpheus quote. I was indeed confused. Good catch! Please disregard whatever I said about the thermal energy then.

Also, interesting idea about the deep compulsion to care about human race. This sort of plays into the movie mythology in which human element in the form of “The One” was sort of a self-balancing element of the matrix.

[quote comment=”11600″]Even by your interpretation, humans as an energy source are finite. […] [T]he movie strongly suggests the notion of humans an indefinitely renewable energy source when that is simply an impossibility. Humans ultimately derive their energy from the sun, and without it, the machines need to draw from their own stockpiles to grow them. It simply goes in a circle with a constantly decreasing stockpile.[/quote]

I agree with your conclusion, but not your premise. How did you come to the idea that no energy whatsoever enters the system? Humanity “scorched the sky, not “turned the sun off”. Some external energy will still be entering earth; the only thing we know is that the sunlight is too weak, too irregular, or at inconvenient frequencies, for existing solar panel technology to be useful.

So the key question is indeed: what are the machines feeding the grown humans to add energy to the system? (Morpheus mentions the recycling of dead people, but that is merely recycling of resources, it does not add energy.) I think a fair guess is that some algae, plant or bacteria used to very harsh environments (and thus not dependent on direct sunlight) may have survived — or — was possible to quickly bio-engineer. However, algae, plants and bacteria do not produce electricity, so you need to convert those specific kinds of chemical energy to electricity with optimal efficiency. My point is that it is not self-evident that burning the algae in a heat engine is better than using a setup like the Matrix.

[quote comment=”11600″]No matter how energy efficient the Matrix was, I’m pretty sure that by applying the same techniques to a heat engine would be more efficient, simply because there are so many fewer points of failure, and opportunities for heat loss.[/quote]

Here, I simply do not agree. If we start with some kind of chemical energy in an algae (which derive its energy from incoming weak sporadic sunlight or radiation, or similar.) this is a fairly low-entropy form of energy. A heat engine would first convert the chemical energy to heat, which increases the entropy of that energy. The limit for best possible efficiency is then set by Carnot’s theorem. On the other hand, a non-heat-engine conversion method can avoid the first entropy-increasing step of converting the energy to heat, and can thus achieve a higher efficiency. Maybe such a conversion method could be compromised by the human digestive system -> neural electric energy.

First: Burning humans and converting the heat to electricity works well enough as long as there are humans around to burn. But what do you do when you run out of “fuel”? You need to establish some kind of re-growth. Hence, you do need to grow humans for crop anyway, etc.

Even by your interpretation, humans as an energy source are finite. The difference between burning people and ‘growing’ them, is in immediacy and effort. It clearly takes the machines a stupendous amount of energy to grow, and contain the humans. It also takes a lot of time, and they aren’t increasing their lot by doing it. Assuming that they have batteries of even moderate efficiency, (as opposed to those huge and constant electrical discharges you see in the movie,) I think that they’d be better off simply burning people from the get-go and storing the energy in a more convenient form, or freezing people and burning them when they need the energy.

Either way, the movie strongly suggests the notion of humans an indefinitely renewable energy source when that is simply an impossibility. Humans ultimately derive their energy from the sun, and without it, the machines need to draw from their own stockpiles to grow them. It simply goes in a circle with a constantly decreasing stockpile.

Maybe the way the Matrix is setup this conversion happens to be more efficient than a typical heat engine.

No matter how energy efficient the Matrix was, I’m pretty sure that by applying the same techniques to a heat engine would be more efficient, simply because there are so many fewer points of failure, and opportunities for heat loss.

Then again, I’m not an evil machine from the future, so , what do I know?

[quote comment=”11590″]I believe that the Matrix movies specifically stated that they use thermal output of human bodies as energy source – which would mean that they are not tapping to the kinetic energy, the chemical energy and etc. But maybe I’m confused.[/quote]

I think you are confused, this is what Morpheus actually says: “The human body generates more bio-electricity than a 120-volt battery and over 25,000 BTUs of body heat. Combined with a form of fusion, the machines have found all the energy they would ever need.” I read bio-electricity to mean electricity tapped from our neurons through the Matrix. I think this is the important energy, and that the “BTUs of body heat” are basically only used just like we try to use surplus heat from e.g. reactors for heating homes.

The thing with neural signals is that their output would be minuscule compared with what they could get from thermal output alone.

[quote comment=”11591″]If the entire purpose of the matrix is to convert the calories in human tissue into electrical energy, it would have been far more efficient to simply burn people as a fossil fuel.[/quote]

Are you sure?

First: Burning humans and converting the heat to electricity works well enough as long as there are humans around to burn. But what do you do when you run out of “fuel”? You need to establish some kind of re-growth. Hence, you do need to grow humans for crop anyway, etc.

Second: the processes in our bodies convert chemical energy in our bodies to bio-electricity. How have you concluded this conversion is so inefficient? Maybe the way the Matrix is setup this conversion happens to be more efficient than a typical heat engine.

[quote comment=”11590″]Maybe it’s like in Hyperion novels where (FALL OF HYPERION SPOILER) the AI were using human brains as their processing medium.[/quote]

I do like this line of thinking. I think it is clear that the Matrix has become a very integral part of the machines, and maybe it has several purposes.

[quote comment=”11592″]The Matrix is really just an elaborate way to screw with us.[/quote]

I have also been thinking along similar lines. Maybe deep inside the AIs that control the machines there are some code embedded that establish a “need” for the machines to take care of humans. A bit like Asimov’s robot laws. Hence, the existence of the machines would be meaningless without humans and they constructed the Matrix to be able to keep humans around in a way that best guarantee our survival.

Maybe the machines’ AI only got to the point of being a 5-year-old with a magnifying glass, and we’re the ants. The Matrix is really just an elaborate way to screw with us.

I like the idea of them using our brains as processors. That makes more sense to me and the whole battery idea could be propaganda that they spewed out because we would figure they have plenty of power, so there’s no reason to disconnect (and sacrifice) a bunch of humans. However, if we knew that the brains were being used to process their AI, we would potentially be able to figure out which clusters are most important. Though, if this were the case, it would probably mean that the cycles necessary to run the Matrix are also coming from this brain network. So we’re really screwing ourselves over. Gosh guys, can’t you just pretend my life is the coolest ever for a few minutes?

All “energy production” is energy conversion. One get energy in inconvenient forms (e.g. sunlight) and needs to convert it into convenient forms (e.g. electricity). This is the problem the machines in the Matrix has.

This would make sense except it doesn’t square with what happens in the movie. If the entire purpose of the matrix is to convert the calories in human tissue into electrical energy, it would have been far more efficient to simply burn people as a fossil fuel.

@Tino: Yeah, you are correct – energy is conserved. I believe that the Matrix movies specifically stated that they use thermal output of human bodies as energy source – which would mean that they are not tapping to the kinetic energy, the chemical energy and etc. But maybe I’m confused.

Still, they probably be at a loss because we do store energy in fat tissues for future use and this energy wouldn’t be easily accessible to the machine – it could be eventually extracted post mortem or by inducing muscle spasms which would then theoretically use the calories stored in fat tissues and output them in the form of kinetic energy.

The thing with neural signals is that their output would be minuscule compared with what they could get from thermal output alone. But I like your theory.

Oooh! Maybe it’s like in Hyperion novels where (FALL OF HYPERION SPOILER) the AI were using human brains as their processing medium. So humans are not really batteries but a gigantic distributed cluster running the machine city AI. The matrix is just a simulation that keeps the people occupied and distracted while the machines are using their brain power for processing.

I wonder if a biological cluster of human minds like that would actually have lower energy requirements than an equivalent cluster constructed with traditional hardware. It probably would.

I don’t have the numbers to support this but I really think that we do require more input energy than we output thermally.

You seem a bit confused with the physics here. Energy is not created or destroyed. The energy that goes into a human increase the mass of the human until it is later released in some form (thermal, or mechanical, or poop-mass, etc.). The sum exactly adds up, except for the mass that stays inside our body when we grow (well, for people who appreciate finer details, there is supposed to exist a loophole through general relativity, but that is not very relevant here). All “energy production” is energy conversion. One get energy in inconvenient forms (e.g. sunlight) and needs to convert it into convenient forms (e.g. electricity). This is the problem the machines in the Matrix has.

Hence, there is no sense in arguing “there is no point with this, growing humans cost as much energy as it produces”. The same thing goes for growing crop, or farming animals. Yet, these are activities humanity is engaged in today because we cannot absorb sunlight. We prefer our energy converted to e.g. wheat and meat that we can absorb.

Now, my take on the movie is that the machines are well equipped at using the energy in human neural signals. Remember, they have evolved from technology developed by humans, and I am sure that at some point in our future it made sense to power e.g., smart computers with our own neural energy.

Hence, when solar panels did no longer work, this was the energy type the machines were best equipped for using. So they grew humans and constructed the Matrix for extracting neural energy from the grown humans. This “fake world” was needed, because the brains have to be stimulated to exert neural energy. The Matrix is like a gigantic milking machine.

Of course, I have no references for any of this. It is just my interpretation of what goes on in the movie.

[quote comment=”11578″]I wonder if the energy output of a human is worth the input required to keep the human alive.

Human creation: growing a human seems like a cloning process.
Basic nutrition: the dead is liquefied to be fed intravenously to the living.
Running the matrix: the whole illusionary world surely requires some sort of super mainframe for millions of people to connect to.

These activities must be super efficient!
[/quote]

No, of course not. It’s the first law of thermodynamics, no system can output more energy than it receives. The best the machines could hope for in a regime of growing people from scratch and harvesting their energy output (in all forms, including the kinetic energy output though pooping,) is to break even. This is assuming that the process requires is absolutely efficient and that every energetic output is gathered.

In practice, our electrical output is only a small subset of the energy needed to keep us alive, so the machines would be operating at a fantastic loss. So, no, there is absolutely no way in hell that the scheme in the movie is sustainable. Until you reach the “combined with a type of fusion” part, at which point, you wonder why they don’t just use the fusion alone. It must be very efficient to fuel this human-growing scheme.

Since I wasn’t using my own computer, it went to screen saver which is the scrolling matrix code. A coworker was passing by and was like “Woha! What is that?!”.

“Matrix screen saver” I explained. He looked disappointed.
“Oh… I thought you were programming or something like that” he mumbled, and left the stage before I was able to go all *facepalm* on him. I mean, it’s like a compound double fail. One fail for not recognizing matrix code. Second fail for thinking this is how programming looks like.

Remember a story on the Daily WTF where a biologist saw a Matrix screensaver on one of simulation computers in his lab and asked the coder a similar question. The coder responded that he didn’t see the code anymore and only saw things like blond or redhead. The biologist never caught on apparently.