The thought experiment: What would happen if the internet suddenly stopped working?

After one day

At the end of the first day, Facebook and Google have lost over £300m in advertising revenue between them. Most other businesses have ground to a halt as well, since banking, telephone and mobile phone networks all rely on the internet to function.

After a week

The modern power grid relies on the internet to coordinate power plants and electricity substations. Without it, each country’s national grid has become unbalanced, and local outages escalate into a blackout for most of the world. Gas pipelines have shut down since they rely on power and the internet.

After a month

Petrol stations use electricity to pump fuel, and they need an internet connection to monitor tank levels, process transactions, and order new deliveries. Without fuel, supermarkets can’t deliver food, and riots rage around all the major distribution depots. The army is called in, but they need fuel and supplies too.

After a year

In the developed world, most countries have recreated a basic landline telephone network, and have begun to rebuild society. Everywhere else has reverted to an agrarian subsistence economy. The death toll from starvation, cold and unrest is estimated at a billion worldwide. The global economy is back to 1930s levels.

Read more:

• The thought experiment: What would happen if everyone on the planet suddenly went vegan?
• The thought experiment: What would happen if aliens contacted us?

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