To understand radio signals, one must break with traditional notions.

Signal transmission isn't about the electrons themselves moving but rather the energy transfer facilitated by electrons.

It's akin to how water waves work, where the source generates waves, propelling them forward, yet the water itself doesn't move extensively, sometimes even flowing in the opposite direction.

In the realm of traditional low-frequency signal transmission, a wire plus ground suffices. Given the low signal frequency, one level is conveyed from the source to the receiving end before the next level is generated, allowing a separate wire to complete the energy balance loop.

In theory, high-frequency signals, as long as the source and endpoint are in proximity, could also utilize a separate line for the return path. However, practical limitations make this impossible, leading high-frequency signals to follow diverse return paths.

It's essential to recognize that all signals, not just high-frequency ones, are transmitted in the form of electromagnetic waves. Unless the interval between two signal levels exceeds the signal transmission time, the return path can be viewed as a DC transmission mode.

An interesting fact is that the speed at which electrons propagate is only about 1cm/s, while signals travel at the speed of light.

In the realm of astronomy, on October 24th, CNN reported the observation of a mysterious radio wave that had traveled for 8 billion years to reach Earth. This radio signal was a fast radio burst (FRB), one of the most distant and energetic ever observed by the scientific community.

Fast radio bursts are intense bursts of radio waves lasting milliseconds, and their origin remains an enigma. They were first observed in 2007, and since then, hundreds have been spotted emanating from the distant universe.

A recent study published in the October 19th issue of the U.S. journal Science highlighted an FRB known as FRB20220610A. Although it lasted less than a millisecond, it released energy equivalent to what the Sun emits over 30 years.

The fleeting nature of fast radio bursts makes them challenging to study. Radio telescopes like the Array of Square Kilometer Pathfinders (ASKAP) in Australia have been invaluable in tracking these cosmic flashes. In June 2022, astronomers used ASKAP to observe an FRB and ascertain its source.

One of the study's contributors, astronomer Stuart Ryder from Macquarie University in Australia, explained, "We used ASKAP's antenna disk array to pinpoint the direction of its source.

We then employed the European Southern Observatory's 'Very Large Telescope' in Chile to search for the source galaxy. We discovered that this source galaxy is older and more distant than any other source galaxy of fast radio bursts.

This suggests that fast radio bursts may originate in a small group of merging galaxies, unveiling a fascinating celestial mystery.

Fast radio bursts (FRBs) continue to captivate astronomers with their mysterious origins. These brief but intense bursts of radio waves, first detected in 2007, have been observed in their hundreds, yet their source remains enigmatic.

The latest revelation, FRB20220610A, presents an astonishing case. Although it lasted for less than a millisecond, it unleashed energy equivalent to what the Sun radiates in 30 years.