At SubOptic 2023, my colleague Tim Stronge and I brought back the *Telecom Mythbusters* to test a new series of myths.

I already covered my first two myths from our presentation: the cable lifespan myth and the 99% myth.

My third and final myth—the exponential growth myth—is based upon a quote that I found.

“The greatest shortcoming of the human race is our inability to understand the exponential function.” –Albert Allen Bartlett

#### The Source of This Myth

Al Bartlett, a professor at the University of Colorado, is known for delivering an hour-long lecture called “Arithmetic, Population, and Energy: Sustainability 101” a whopping 1,792 times.

The focus of this lecture was on exponential growth and the impact on population growth and energy consumption.

#### What Is Exponential Growth?

As you’ll see in the slide below, exponential growth occurs when a quantity increases over time in proportion to its current value. It’s often viewed in terms of percentage growth or as doubling time.

The chart plots exponential growth as the aqua-colored line and linear growth as the dark blue line.

In the linear growth sequence, the y-values increase by an increment of three each period. In the exponential growth sequence, the y-values are multiplied by three over each period.

You can see a much higher growth rate happening with exponential growth.

#### Why Is Exponential Growth Hard To Grasp?

Dr. Bartlett talked about how hard it is to grasp exponential growth in his lecture, using an example with bacteria.

Dr. Bartlett’s example—illustrated above—provided the following assumptions.

There is a jar with bacteria in it, doubling every minute. At 11:00 a.m. the jar has one bacterium, and 12:00 p.m. the jar is full.

Dr. Bartlett would then ask the audience two simple questions:

- When is the jar half full?
- How full is the jar at 11:55 a.m.?

The first answer is pretty obvious. We know that the jar is doubling every minute, so it must be 50% full at 11:59 a.m

The second part—how full the jar is at 11:55 a.m.—was Dr. Bartlett’s main question for the audience. And the answer is 3%.

Shocking, right? Five minutes until the jar is totally full, it’s only at 3%.

#### Let’s Test Ourselves—With a Submarine Cable

Tim Stronge and I tackled this myth and five others during our presentation at SubOptic 2023. Download our slides for the full breakdown.

#### Alan Mauldin

Alan Mauldin is a Research Director at TeleGeography. He manages the company’s infrastructure research group, focusing primarily on submarine cables, terrestrial networks, international Internet infrastructure, and bandwidth demand modeling. He also advises clients with due diligence analysis, feasibility studies, and business plan development for projects around the world. Alan speaks frequently about the global network industry at a wide range of conferences, including PTC, Submarine Networks World, and SubOptic.