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READ: Acceleration

A Historian Reflects on a Lifetime of Change

Highway with car lights© Pete Leonard/CORBIS
By Cynthia Stokes Brown
Acceleration, an increase in the rate of change, is occurring both in the Universe and in human culture on planet Earth.

Definitions

In 2011, three astronomers were awarded the Nobel Prize in Physics for discovering in 1998 that the expansion of our Universe is accelerating, rather than decelerating as they had expected. They found that the galaxies farthest away from our Milky Way galaxy are flying away from us faster than the galaxies nearer to us. The astronomers discovered this by charting changes in the distances of far galaxies, which they measured by observing supernovae that exploded in them. This means simply that the expansion of our Universe is happening at a faster and faster rate. That is, it is accelerating.
NGC 281 or the “Pacman Nebula,”X-ray: NASA/CXC/CfA/S.Wolk; IR: NASA/JPL/CfA/S.Wolk
Apparently this accelerating expansion of our Universe has not always been the case. It seems to have started about 5 billion years ago, about the same time that our Solar System began. No one knows what anti-gravity force can be pushing the farthest galaxies away faster and faster. Astronomers are calling this unknown force “dark energy” and are estimating that it fills about 70 percent of space. Stay tuned as astronomers learn more about this.
Here on Earth a different kind of acceleration is happening. For humans, acceleration means that the rate and scale of cultural change is increasing. David Christian wrote in his book Maps of Time that it might not be an exaggeration to claim that “more change has occurred in the 20th century than in all earlier periods of human history.”

Evidence for Acceleration

What do we mean when we say that the rate and scale of cultural change are increasing? What evidence do we have? How can we measure change?
On the cosmological or geological scale, change is measured in millions or billions of years. On the biological scale, with natural selection setting the pace, change occurs in thousands to millions of years. On the scale of human culture, large-scale change used to occur over millennia or centuries, but now it is taking place in decades or even years.
Let’s look at the length of time that each of the major periods of human history has lasted. The Paleolithic era, or the era of hunting and gathering, lasted from the beginning of our species about 250,000 years ago to about 10,000 years ago. That’s about 240,000 years, or 240 millennia. The period of agriculture lasted about 10,000 years, or 10 millennia, while the modern industrial era has lasted 200 years, or a fifth of a millennium. Do you see a pattern of accelerating change? Each era lasted for a much shorter period of time than the earlier one. Now we seem already to be near the beginning of a new era, since we cannot continue long in our present mode: oil is running out, and the burning of fossil fuels is changing our climate.
Zooming in on the 20th century, we might begin by looking at the increase of human population. In 1900 the Earth had 1.6 billion people, in 1950 it had 2.5 billion, and in 2000 it had 6.1 billion. In other words, it just about doubled twice in one century. In the lifetime of anyone who lived through the last half of the 20th century, the human population doubled in 40 years. This has never happened before in anyone’s lifetime. Since 2000 the rate of population growth has slowed somewhat, but the human population has still increased to 7 billion. This total represents an enormous, rapid, and unprecedented change for humans and for the planet.
The number of people who have ever lived is estimated to be about 80 billion. Of those, 20 percent have lived in the modern era. About 8 percent (7 billion divided by 80 billion) of all humans to walk the Earth are alive today.
What has made it possible for so many people to survive and live a long life? (Average worldwide life expectancy has risen from about 35 years in 1900 to about 66 years in 2000.) The answer seems to lie in the increased interplay of energy flowing through human systems and increasing innovations in human technology.
The force that propels the acceleration of change in human societies today is the burning of fossil fuels — coal, oil, and natural gas — and the technological innovations of the modern era. Oil came into use in the early 20th century, revolutionizing transportation by fueling cars, trucks, tractors, airplanes, and tanks. During the 20th century energy use in the world expanded 13-fold, which included oil production soaring sixfold just from 1950 to 1973. The three fossil fuels provide energy that originated from the Sun and was sent to Earth millions of years ago, supporting early life forms, preserved somewhat in their remains and then retained underground or under the sea until humans retrieve it. This extra energy propels our food production and our technologies (transportation, communications, financial systems, space exploration, and military actions). Our global civilization is based on fossil fuels at the present time. As of 2010 only about 16 percent of global energy comes from renewable sources.
More people and more energy from fossil fuels has added up to a great increase in the size of the global economy — a 10-fold increase since the end of World War II in 1945. The period since then is sometimes called the “Great Acceleration,” because global increases in population, production, and energy use have increased at a previously unknown rate.

Technology Over Three Generations

Elevated roadways in Shanghai, China© Joachim Ladefoged/VII/CORBIS
The changes in technology that occurred in the 20th century may be more vivid if I compare some aspects of the life of my grandmother, Bertha Mantz Bast, who lived from 1888 to 1987, with aspects of mine.
My grandmother married my grandfather, Paul Jacob Bast, in 1909. They lived with his parents on a dairy farm in southern Wisconsin, 20 miles from Milwaukee. At that time Grandpa already had his first Ford tractor, but they had no electricity, car, radio, or telephone. They traveled only as far as they could walk, or as far as horses could pull a sleigh in winter or a buggy in summer. On special occasions they might take a train. They milked the cows by hand and pumped water into the kitchen by hand. Grandma hung the laundry on lines to dry and grew their vegetables in her gardens. The farm had kerosene lamps, wood stoves for cooking and heating, and a privy (toilet) outside. Everyone bathed in the kitchen in a large wooden tub. Grandma said they were clean and happy.
During Grandma’s life on the farm — until they moved to a city in 1954 — innovations appeared that changed her life immensely. Sometime before 1920 Grandpa bought his first car, a Model-T Ford that had to be hand-cranked to start the engine. (Grandma never learned to drive.) Electricity arrived in 1921, ending the kerosene lamps. Soon there was indoor plumbing, hoses to water the garden, and eventually milking and washing machines, plus radios, telephones, and phonographs. In her 80s Grandma flew on an airplane twice to visit her daughter, who lived in San Salvador, El Salvador.
In my lifetime technological innovations have appeared even faster. Before I married in 1961 antibiotics had come into use to help fight illnesses, color television (1940) had been invented, as well as atomic energy (1945) and credit cards (1950). After my marriage the first man landed on the Moon in 1969, the first IBM PCs appeared in 1981, and the first Apple Macintoshes in 1984.
After that the list accelerates even more:
1990 World Wide Web
1991 First hydrogen fuel cell for automobiles
1992 Digital cell phones
1995 DVDs
1997 Toyota hybrid car released in Japan
1998 High-definition television
2000 Nano-Tex fabrics
2001 New artificial heart and liver technology; iPods
2004 Facebook
2005 YouTube
2007 New record of efficiency in solar cells
2010 First iPad
Now in my later years I am much more hopelessly out of date than my grandmother ever was. I have a much harder time keeping up with the innovations that keep appearing because the pace of change has accelerated. Yet the payoff for me has been staggeringly wonderful. Now I can connect almost instantaneously with anyone in the world and with all the knowledge in the world. I can jump in a plane and be anywhere within hours. I can finish the maintenance work of my daily life in very little time. Grandma would hardly be able to believe it, and she’s been gone only 25 years.
In these paragraphs I have described only innovations as they have affected daily life. But technology has transformed all areas of human life. Today human activity is connected in a simultaneous global network never before attained on Earth — an exchange network that includes medicines, foods, and weapons. What will the pace of change be like during your lifetime?

For Further Discussion

What examples of acceleration have you noticed in your life? Are you able to do things today because of technological innovation that you were not able to do a few years ago? Share your answers in the Questions Area below.

Want to join the conversation?

  • blobby green style avatar for user JHCashion
    What is acceleration and what causes it?
    (8 votes)
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    • female robot grace style avatar for user 00015651
      Acceleration is the process of increasing movement or change in an object. According to newton it occurs when there are unbalanced forces; according to big history it is caused by complexity.

      Acceleration is caused by complexity. It occurs because things build up to a conclusion. Marie Curie discovered the workings of the invisible world in atoms(I refer to invisible as something that cannot be seen with the human eye). If she had not done that Rutherford and Thompson would not have been able to discover the nucleus and electrons of n tom,respectively. Just like in today's world if there were no digital phones , then we would not have iPhone or Samsung at this moment in time take the car for example, Germany and Japan have historically been places where resources to build industry were scarce and had to be imported or other means not in mainstream culture had to be used e.g. energy efficient methods. The understanding of a need that needs to be fulfilled is complexity and thus acceleration as it carries us to the next step.
      (10 votes)
  • starky tree style avatar for user Keepa.Paaka
    Wasn't the world wide web originally made in 1989? But then again it was made public in 1993. Please tell me if i got the wrong answer Arigatō. (thanks)
    (4 votes)
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  • blobby green style avatar for user Hernandez, Jayme
    What caused acceleration? Why was social media invented?
    (5 votes)
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  • female robot grace style avatar for user Agneta Rosenheck
    As it is an article I can only comment that 200 years out of millennium is only one-fifth. (Evidence of acceleration, paragraph 3)
    (3 votes)
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  • blobby green style avatar for user Monique Dean
    Things that have accelerated in my life is technology. Everything from computers to cellphones to t.v. to ipads or tablets and social media. I look at it as a way to stay or get in contact with friends or loved ones. Computers and email or texting is the new way of writing letters and it will get to that person faster. Television going from a black and white picture show to a HD t.v. that makes you feel like your there. Very interesting to see how far technology has come and has changed lives and connecting with the world in ways no one could ever imagine.
    (3 votes)
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  • leafers tree style avatar for user DarkFire101
    What examples of acceleration have you noticed in your life? Are you able to do things today because of technological innovation that you were not able to do a few years ago?

    A push in electric vehicles, new and advanced space travel, new more advanced AI, full self-driving and landing capabilities of spaceships.

    I can ride in a fully electric car, play video games in Virtual reality, and buy a robot to protect my home or business.
    (2 votes)
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  • blobby green style avatar for user alton west
    I would say a big change I've seen in my lifetime would be the evolution of communication.from land lines to wireless cell phones to the types of cellphone available for use like the invention of the iPhone being that it's hand held completely touch screen a dis really like a portable computer organizer phone callendar you name it! It is amazing and I can do so much more now than I could even imagine say just 10 to 15 years ago
    (2 votes)
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  • blobby green style avatar for user leonard.tj15
    I am able to use my smartphone everyday for directions on google maps look up any information on the internet and connect with anyone in seconds and it is improved everyday. when I was younger we had flip phones that barely texted or mad calls and kinda hooked up to the internet. now we have smart phones that do it all and then some.
    (2 votes)
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  • blobby green style avatar for user ilovelivingthislife
    Examples of acceleration that ive noticed in my life would have to first be the technology ive adapted to upgrading my knowledge on such as computers to smart phones, ive been able to learn about the many ways of communication or interaction via world wide web from audio and or video chatting even just sending an email. Ive found out that you are able to text a persons cell phone from your email and as long as they respond you can converse that way even if you do not have a phone to text with, i also figured out on my own theres thousands of wifi signals that are free which can allow you to communicate from a capable electronic devise without service temporarily.
    (2 votes)
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  • spunky sam green style avatar for user Sabrina Groom
    An example would be me being able to use my computer, phone, and car every day. Yes, I am able to do things today because of technological innovation that I was not able to do a few years ago.
    (2 votes)
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