- Ramsey County, Minnesota (Wikipedia)
Ramsey County is a county located in the U.S. state of Minnesota. As of the 2020 census, the population was 552,352, making it the second-most populous county in Minnesota. Its county seat and largest city is Saint Paul, the state capital and the twin city of Minneapolis. The county was founded in 1849 and is named for Alexander Ramsey, the first governor of the Minnesota Territory.
- North Oaks is an exurban city 10 miles (16 km) north of Saint Paul in Ramsey County in the U.S. state of Minnesota. The population was 4,469 at the 2010 census.
- Black hole (Wikipedia)
A black hole is a region of spacetime where gravity is so strong that nothing, including light or other electromagnetic waves, has enough energy to escape it. The theory of general relativity predicts that a sufficiently compact mass can deform spacetime to form a black hole. The boundary of no escape is called the event horizon. Although it has a great effect on the fate and circumstances of an object crossing it, it has no locally detectable features according to general relativity. In many ways, a black hole acts like an ideal black body, as it reflects no light. Moreover, quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is of the order of billionths of a kelvin for stellar black holes, making it essentially impossible to observe directly.