1. Within means not outside a place.
Pattern: be + within + noun
Those schools are within the county jurisdiction.
There is too much commotion within the building.
Typical nouns used after within:
area, building, city, country, county, jurisdiction, state, territory, walls
2. Within means less than a period of time.
I will return within the hour.
He will finish within five minutes.
3. Within means less than a distance.
There is a hospital within five miles of the school.
The storm was within ten miles of our town.
4. Within means possible; not exceeding the limits of something.
Pattern: be + within + (one’s) noun
At last, the beach is within sight!
A fortune is within our reach if we are lucky.
Typical nouns after within:
bounds, hearing, range, sight, reach, the law, the limit, the rules
to keep within the family—to not reveal something to anyone who is not a family member
That man has a strange history, but they keep it within the family.
Famous Indian Scientists
Amal Kumar Raychaudhuri
Amal Kumar Raychaudhuri (14 September 1923 ? 18 June 2005) was a leading Indian physicist, renowned for his research in general relativity and cosmology. His most significant contribution is the eponymous Raychaudhuri's equation, which demonstrates that singularities arise inevitably in general relativity and is a key ingredient in the proofs of the Penrose-Hawking singularity theorems. Raychaudhuri was also revered as a teacher during his tenure at Presidency College, Kolkata. Many of his students have gone on to become established scientists.Raychaudhuri was born to Surabala and Sureshchandra Raychaudhuri on September 14, 1923 in Barisal of undivided Bengal in British India, which is now a part of Bangladesh. His father taught mathematics at a school in Kolkata. His father's cousin, Professor Hemchandra Raychaudhuri was a renowned historian and the Carmichael Professor of History at the University of Calcutta.
Raychaudhuri received his early schooling at Tirthapati Institution in Kolkata and went on to complete matriculation from Hindu School. He demonstrated an aptitude for mathematics at an early age. He graduated from Presidency College in 1942 and completed his M.Sc. at Calcutta University in 1944.
After earning his master's degree, Raychaudhuri spent four years doing experimental work.During this time, working in complete isolation, he taught himself differential geometry and the theory of general relativity. In 1952 he took a research job with the Indian Association for the Cultivation of Science (IACS), but to his frustration was required to work on the properties of metals rather than general relativity, which was not yet considered to be truly part of the mainstream of physics. Despite these adverse pressures, he was able to derive and publish the equation which is now named for him a few years later.Some years later, having learned that his 1955 paper was highly regarded by notable physicists, such as Pascual Jordan, Raychaudhuri was sufficiently emboldened to submit a doctoral dissertation, and received his degree in 1959.In 1961, Raychaudhuri joined the faculty of his alma mater, Presidency College in Calcutta. Ironically, his work was not widely recognized in India until the nineteen seventies, when he became a well known scientific hero. Shortly before his death, a documentary film on his career was completed.