What does space-time accompaniment mean?

The meaning of space-time accompaniment is as follows:

Space-time companion, a new term that gave birth to COVID-19 epidemic. ?

It means that my phone number and confirmation number stay in the same space-time grid (the range is 800 m * 800 m) * * for more than 14 minutes, and the cumulative stay time of any number in recent 14 days exceeds 30 hours, and the found number is a space-time companion number. ?

Before the time-space companion, people who investigated the risk of infection in COVID-19 were managed by close contacts. Comparing their definitions, we can find that the biggest difference lies in the further expansion of their spatial scope.

Definition of words:

Space-time companion number means that my phone number and the number of the confirmed patient stay in the same space-time grid (the range is 800 m * 800 m) * * for more than 14 minutes, and the cumulative stay time of any number in the last 14 days exceeds 30 hours, and the found number is the space-time companion number.

My green health code will turn into a yellow code with warning nature, and will be marked as "time companion" by the system. For example, the infected person has been to a certain place within 14 days, and the trajectory of you 14 days intersects with him. Whether it is a physical passing or a drift in communication signals, it may be considered as a "time companion."

The correct way:

Health code yellow code personnel and time-space associated risk personnel who received SMS reminders from the Public Security Bureau and the Municipal Center for Disease Control and Prevention should immediately report to the community and conduct two nucleic acid tests within 3 days, with the interval between the two nucleic acid tests being more than 24 hours. Please stay at home and don't go out until you get a negative result of nucleic acid.