query: How are billion-year half-lives approximated?
positive_passages.docid: 25373
positive_passages.text: How do we know that some radioactive materials have a half life of millions or even billions of years?
negative_passages.docid: 41750
negative_passages.text: The age of the universe
negative_passages.docid: 45557
negative_passages.text: How many ancestors alive 1000 years ago does a person have on average?
negative_passages.docid: 65566
negative_passages.text: Estimating age of the universe by Hubble's law?
negative_passages.docid: 50415
negative_passages.text: Value of the Hubble parameter over time
negative_passages.docid: 118407
negative_passages.text: Birthday Problem applied to collisions
negative_passages.docid: 132273
negative_passages.text: How precisely can we date the recombination?
negative_passages.docid: 99110
negative_passages.text: Question about probability? World Population - (Question Revised)
negative_passages.docid: 152335
negative_passages.text: Calculate distance of galaxy 13 billion years ago
negative_passages.docid: 53960
negative_passages.text: birthday problem - expected number of collisions
negative_passages.docid: 52373
negative_passages.text: Predict decay chain of a radioactive element
negative_passages.docid: 5514
negative_passages.text: Why is carbon dating limit only 40,000 years?
negative_passages.docid: 114934
negative_passages.text: Bootstrap Paradox in Interstellar
negative_passages.docid: 132545
negative_passages.text: How much energy is necessary to set a year to exactly 360 days
negative_passages.docid: 115987
negative_passages.text: How can time be relative?
negative_passages.docid: 72072
negative_passages.text: How about an exact solution for the position of a planet as a function of time?
negative_passages.docid: 109273
negative_passages.text: Extending the birthday paradox to more than 2 people