When it comes to network diffusion of information or influence, all bridges (a line in a network graph that represents the only connection between two points) are weak ties.
Why? Because the stronger the tie between two individuals, the more overlap they have in friendship circles therefore no strong tie is a bridge.
This also means that weak ties are important because they can be the only way in which information or influence can travel. Indeed, removal of a weak tie does more damage than a strong tie.
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The removal of the average weak tie does more damage than the removal of the average strong tie when it comes to diffusion of information in a social network. Often the shortest and only connection between different nodes in social network are weak ties.
A study that analyzed anonymized employee-level (email, calendar, etc.) found that the sudden shift from the office to remote work resulted in a silo’ing effect—employees spent more time with strong ties and less time with weak ties from December 2019 to June 2020.