Consider the Mass of a Single Idea

It’s pretty safe to say that there are more ideas in the world than at any other time in human history. And not just that, but there are more ideas per capita in the world than any thinking mortal could have dreamed of. These ideas, thoughts coded and presented often blindly via electronic communication, are mostly left to dry out in some server farm with a few “likes” and not much else. But they’re here on the planet with us for quite possibly a long time, maybe even a lifetime and beyond. It’s hard to say for sure actually, but deleting data/ideas is out of fashion, a task increasingly not worth the trouble. Memory is cheap even for the very cheapest thoughts.

Sometimes you see things about the internet’s backbone and generally baffling infrastructure: cables under the ocean, fiber-optic cables over mountain passes, server farms dropped onto the plains. We’re briefly impressed and then go on being sold near continuously the notion of “the cloud.” That’s where your ideas are, in some pinkish white ether governed by Amazon or Google. But that ether is really server racks in a room holding a bunch of shared physical storage via things made of glass, ceramic, copper, etc. Your ideas are locked in a very well air conditioned room with a bunch of other people’s ideas. They have a size, shape, and demand electricity.

So, it’s all a bunch of physical stuff, more than most people think about. There’s mass in all of that stuff, obviously, but can you strip it all away and still have the idea? Just like your body or a subway train or a black hole all have mass, the idea must too, I think. This is in debate, however, and many would argue otherwise. Ideas aren’t things at all, but are only conveniently translated to things like hard-drives and language: the question is silly, like asking if politics has mass. Aspects of politics have mass—voting machines, leaflets, a human canvasser—but as a whole, the mass question is not one that can be applied to “politics” in a reasonable way. So too we can argue that an idea is by definition not a physical thing. An idea in its most pure state does not have units.

For an idea to matter, though, it must become information (maybe you can just accept that it's information in the first place). Or an idea that matters is information. Information is a thing. (I recommend James Gleick’s The Information for a good unpacking of this idea.) As a thing, information has mass. Information is material and it blankets the planet thicker and thicker every day, like a snowball that doesn’t move but still gathers up more and more snow. The easiest answer is that the mass of information, or a single bit of information (a 1 or 0), is equal to the mass of an electron, the particle carrying a 1 or 0 message in an electrical communication system: .00001 grams. Very, very small. This is the minimum needed to communicate any message with meaning—to have an idea that matters.

A study out in last month's IEEE Proceedings reconsiders that basic idea in light of quantum mechanics, with one totally bizarre implication being the possibility of negative masses, or anti-information. The first problem pointed out by the authors, Laszlo B. Kush of Texas A&M and Claeos G. Granqvist of Sweden's Uppsala University, is that an electron is not actually the smallest thing that information can be encoded on. Electrons are nice because they can also be used for storage via magnetization, but photons, particles of light, can also carry messages via polarization. Information can’t yet be stored with photons, but it can be sent. In this situation, the mass is about a million times less than that of a resting electron (remember: mass is related to energy).

This is sort of apples to oranges, however. The theoretical mass of a resting photon is actually zero. No energy, no mass. Photons don’t rest though. You can slow the frequency of light way, way down, to nearly zero, but quantum mechanics in a sense forbids zero. That is, to slow a photon to absolute zero would violate the uncertainty principle, which is the neat thing in quantum mechanics that states that it’s not possible to know both the position and velocity of a particle at the same time. This is what would happen with a frequency of zero: our photon would be stopped in a single position with no velocity. Impossible. So, it seems that information will always have some tiny little bit of mass, just enough to not be zero.

Photons, lacking storage capabilities, are still not entirely fair to consider for information mass minimums. Electrons are still number one, but the problem here is that if we’re storing a bit of information with an electron, we’re not actually adding an electron. We’re just changing an electron already there. So the mass question gets harder, but still not impossible. What's the difference in masses before and after your information addition?

You can look at it as a change of entropy: if you were to change a system of electrons such that it becomes less ordered or increases in entropy, you will have lost mass (again, as mass and energy are related per good ol’ e=mc²). So, we can imagine a storage device set up in a such a way to not carry a meaningful idea yet have a bunch of energy/mass locked up in it in the form of tightly ordered electrons. In which case, the addition of our idea to the storage device will cause an increase in entropy, and a negative mass as the system becomes more disordered.

The authors point out a practical end to all of this: security. They write:” the observed effects offer a security application, and weight transients conceivably could serve as a “smoking gun” to evidence that a storage medium has been in recent use.” So the ultimate question might be less what is the weight of an idea?—as the researchers demonstrated, as close to zero as possible without being zero—than what is the weight of an idea disturbed? That is still up for experimentation.