Charge acceleration without radiation.

The existence of electromagnetic radiation-radio waves, microwaves, light, X-rays, and so on-is one of the most important physical phenomena, and our ability to manipulate them is one of the most significant technological achievement of humankind. Underlying this ability is our understanding of how radiation is produced: Whenever an electric charge is accelerated, it radiates. Or, at least, this is how it has been hitherto universally thought. Here, we prove that quantum mechanically electric charges can be accelerated without radiating. The physical setup leading to this behavior is relatively simple (once one knows what to do), but its reasons are deep: It relies on the fact that quantum mechanically particles can be accelerated even when no forces act on them, via the Aharonov-Bohm effect. As we argue, the effect presented here is just the tip of an iceberg-it implies the need to reconsider the basic understanding of radiation. Finally, it seems clear that the effect goes far beyond electromagnetism and applies to any kind of radiation.