Part 2. Here is Part 1

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People often think computers are “solved.” Like, we already have fast CPUs, GPUs, AI, cloud, smartphones — so what is left?

But actually, even the basic things we use every day are full of temporary fixes.

One big example is the heat wall.

For a long time, CPU companies made processors faster by increasing clock speed and adding more transistors. But there is a problem: more speed usually means more power, and more power means more heat.

That is one of the reasons why normal CPUs are not running at 20GHz or 50GHz today. We are mostly stuck around a few GHz because after some point, the chip gets too hot, too power-hungry, and too unstable.

The basic problem is physical.

Inside a CPU, we use materials like silicon.

Silicon, Si [14]

When voltage is applied, an electric field pushes electrons through the material. But electrons do not move like cars on a perfect, empty highway. They move more like people trying to walk through a crowded city with broken roads, walls, holes, and random obstacles.

They scatter from atoms, defects, impurities, surfaces, and vibrations inside the material.

When electrons move, they gain energy from the electric field. But when they scatter, some of that energy goes into the material itself. The atoms start vibrating more.

That vibration is what we call heat.

So one dream solution is simple to imagine:

What if we could give electrons a clean road?

A road where they do not crash into defects, atoms, or vibrations so often.

This idea is known as ballistic transport.