While at IBM’s Smarter Computing Summit last week at the tony Pinehurst golf resort, I had the great pleasure of hearing IBM’s Bernie Meyerson talk about limits to today’s tech, and the associated implications. Bernie is IBM’s VP of Innovation and one of the rare technologist/scientist types who can clearly and directly explain highly technical concepts in a way that they can be understood by a reasonably intelligent grey squirrel (and me too).

Even better, he’s highly entertaining and doesn’t hedge when it comes to stating what’s what in the world. Back in 2003 he predicted that Intel would never deliver on their fast CPU (4-5 Ghz) promises and would, in fact, be forced to shift to multi-core processors.

Meyerson backed up his brash prediction (it was plenty brash back then) by sharing electron microscope images of individual atoms that showed they’re kind of lumpy. The problem with lumpy atoms is that when you use only a handful of them to build gates, they leak current like a sieve. When asked about this, Intel denied, denied, denied, that there was a problem – right up to the point when they announced they were scrapping their entire product strategy in favor of a multi-core approach.

So when Meyerson talks, I pay attention. And Meyerson is talking again.

In his presentation at Pinehurst, he was again playing on the theme that we can’t shrink our way to higher performance any more. In fact, when it comes to chips, we have only a generation or two left before we reach the end of the line.

So where’s the end of the line? According to Bernie: 7-9 nanometers. When the features on a chip get to this minute size, you start to see quantum mechanics effects that are “Very nasty,” and include taking way more voltage to change gate state. The problems at 7-9 nm are profound to the point where there isn’t really any way around them – it’s just too damned small – and there isn’t a way to scale down an atom. It’s a fundamental limit, and it’s finally in sight.

Unfortunately, I can’t toss around the correct scientific terms to pretend I know what I’m talking about here. I have only my own deplorable notes for reference; plus Meyerson’s time slot forced him to move pretty quickly through his material. But I think that he might have been talking about quantum tunneling, a phenomena where particles (like electrons and such) travel through barriers, like very thin semiconductor gates, that they shouldn’t be able to cross.

Myerson also talked about the limitations facing us on the storage side. Like most great stories (and many great ideas too), it starts in a bar. In this case, it was Bernie in a bar with a bunch of other smart guys, probably knocking back drinks that aren’t accessorized with little umbrellas. Like all barroom conversations, the topic eventually turned to magnetic storage density. More specifically: how many atoms would you need to reliably store a single bit of data?

This prompted some non-barroom research and scientific activity. The resulting answer? Twelve. It takes twelve atoms to reliably store a bit of data. Any less and you lose stability, meaning that parts of the data might disappear, or morph into something you didn’t store. This is related to the same quantum effects discussed above and are ultimately the result of the fact that we can’t scale atoms down to a handier size.

From what Myerson said, it sounds like we have a bit more room before we start to run up against the limit on storage density. If my notes are correct, we won’t approach the ’12 atom’ limit until we get around 100x more dense. Right now, 1 TB per platter is the highest density available. Theoretically, we may be able to get to 100TB per platter and 300TB per drive at maximum density.

So how long do we have until we hit the limit? It depends on how fast density grows. Historically, we’ve seen density grow anywhere between 20% and 100% per year. Lately (last decade or so), growth has ranged between 20% and 40% annually, meaning that we might hit the twelve atom limit in as few as 13 years or as long as 25 years.

That’s an eternity in the tech business – maybe even long enough for someone to figure out how to shrink atoms down to a more convenient size.