Understanding the Permeability of Free Space
Back in the year 2000, I published a book entitled Telecosm: The World After Bandwidth Abundance. It taught me many lessons about the future, including the treacherous pitfalls in predicting it.
The book began with a grand unification: “The supreme abundance of the telecosm is the electromagnetic spectrum, embracing all the universe of vibrating electrical and magnetic fields, from power line pulses through light beams to cosmic rays.”
Whether light years across the universe or nanoseconds within a single microchip, “the scarcity that unlocks this abundance is the supreme scarcity in physical science. That is the absolute minimum time it takes to form an electromagnetic wave of a particular length.”
This scarcity is called the permeability of free space. It registers the ability of a vacuum to transmit magnetism and thus electromagnetism. Termed mu zero in the equations, it determines the ultimate constant in physics: the velocity of light.
The discovery of the speed of light and of electromagnetism as a unified domain, and its expression in mathematics was the paramount achievement of 19th century science. As physicist Richard Feynman wrote, it reduced the US Civil War of the same year to a “parochial footnote.”
The man who made this epochal discovery was Scottish physicist James Clerk Maxwell. In his honor, I call the spectrum, Maxwell’s rainbow. And as I wrote in Telecosm, “Today most of world business in one way or another is pursuing the pot of gold at the end of it.”
As we explore opportunities today, we find ourselves returning again and again to this quest down Maxwell’s rainbow.
Lessons from Telecosm
The spectrum imposes no limits on this science of shaking, of oscillations or frequencies constrained by lightspeed. Spectral frequencies translate into temperatures, atomic signatures, photon energies, and even Brownian motion of molecules.
In microchips, the speed of light provides crucial stability. If lightspeed changed as the earth orbited the sun at 18 miles a second, electrons moving in a computer would have different speeds depending on the orientation of the device toward the sun. Changing directions, they would change speeds, skewing all functions on chips. A shifting light speed would change the “colors” multiplexed down fiber optic lines and blur the crucial modulations in a message. All physics, chemistry, and information technology is derived from the unification of Maxwell’s rainbow.
It is the low–entropy (predictable) carrier that in information theory enables the high–entropy (surprising or unexpected) messages that bear information. The regularity of the speed of light explains why all information tends to migrate to the electromagnetic spectrum. Its predictability means that the message can always be separated from the carrier at the other end of the line.
In many ways, Telecosm was my best book, full of insights about bandwidth and its uses that are still relevant 20 years later. Telecosm introduced the concept of “store width” which continues to guide our appraisal of opportunities in memory technology. But I made the mistake of predicting the companies that would dominate the new era, such titans as JDS–Uniphase and Terabeam. I declared JDSU the Intel of the Telecosm and announced that we were entering the era of Terabeam.
JDSU did not die, but the crash of 2000 its 60 price–earnings ratio and multi–billion market cap. In 2015, it broke up into Lumentum (LITE) and Viavi Solutions (VIAV). Owner of Oclaro and a pioneer of 3D sensing, Lumentum has nearly tripled in value since the spinoff. Now a test and monitoring company, Viavi still owns part of Lumentum and has risen over 60% since the spinoff. But it is a tiny shadow of the alpine price of JDSU in its heyday.
As for Terabeam, which used the frequencies of fiber optics for free space communications, it was absorbed first by YDI wireless for $52 million and then by Proxim (PRXM), which has diminished to a penny stock. Afflicted with erratic leadership, it ended up behind its rival Lightpointe, an ingenious private company in San Diego, which I neglected to mention in Telecosm.
Telecosm came out in the crash but it continues to sell two decades later and is still the fifth book in the “fiber optics engineering” category on Amazon. It may be worth more than the “Terabeam revolution” it heralded.
None the less, under Proxim, Terabeam went on to replace its infrared light beams from fiber optics with 60 gigahertz millimeter waves, which are now making a new appearance as part of the 5G standard for next generation wireless.
And Lightpointe has turned out to be a successful company, both in free space optics and millimeter wave, and has developed a significant global niche in the field. No one would call it the “Lightpointe era” but former Lightpointe Chief Scientist Erhard Kube has become known as the “father of free space optics.”
More important, however, is the continuing worldwide advance of the fiber optic technology that Telecosm celebrates and explains. Fiber to the home and the premises, growing at some 14% a year, has become central to the new technologies of the 21st century.
We will be exploring them further in our dailies, weeklies, monthlies, and Moonshots. The Telecosm continues toward its pot of gold.
Editor, Gilder’s Daily Prophecy