Weak and Strong Cosmic Censorship Hypothesis
The weak and the strong cosmic censorship hypothesis are two conjectures concerned with the global geometry of spacetimes.
- The weak cosmic censorship hypothesis asserts there can be no singularity visible from future null infinity. In other words, singularities need to be hidden from an observer at infinity by the event horizon of a black hole.
Mathematically, the conjecture states that, for generic initial data, the maximal Cauchy development possesses a complete future null infinity.
- The strong cosmic censorship hypothesis asserts that, generically, general relativity is a deterministic theory, in the same sense that classical mechanics is a deterministic theory. In other words, the classical fate of all observers should be predictable from the initial data. Mathematically, the conjecture states that the maximal Cauchy development of generic compact or asymptotically flat initial data is locally inextendible as a regular Lorentzian manifold.
The two conjectures are mathematically independent, as there exist spacetimes for which the weak cosmic censorship is valid but the strong cosmic censorship is violated and, conversely, there exist spacetimes for which the weak cosmic censorship is violated but the strong cosmic censorship is valid.
Read more about this topic: Cosmic Censorship Hypothesis
Famous quotes containing the words weak and, weak, strong, cosmic, censorship and/or hypothesis:
“... social evils are dangerously contagious. The fixed policy of persecution and injustice against a class of women who are weak and defenseless will be necessarily hurtful to the cause of all women.”
—Fannie Barrier Williams (1855–1944)
“Whose are the truly labored sentences? From the weak and flimsy periods of the politician and literary man, we are glad to turn even to the description of work, the simple record of the month’s labor in the farmer’s almanac, to restore our tone and spirits.”
—Henry David Thoreau (1817–1862)
“The best reason why Monarchy is a strong government is, that it is an intelligible government. The mass of mankind understand it, and they hardly anywhere in the world understand any other.”
—Walter Bagehot (1826–1877)
“A cosmic loneliness was my shadow.”
—Zora Neale Hurston (1891–1960)
“... a phallocentric culture is more likely to begin its censorship purges with books on pelvic self-examination for women or books containing lyrical paeans to lesbianism than with See Him Tear and Kill Her or similar Mickey-Spillanesque titles.”
—Robin Morgan (b. 1941)
“The hypothesis I wish to advance is that ... the language of morality is in ... grave disorder.... What we possess, if this is true, are the fragments of a conceptual scheme, parts of which now lack those contexts from which their significance derived. We possess indeed simulacra of morality, we continue to use many of the key expressions. But we have—very largely if not entirely—lost our comprehension, both theoretical and practical, of morality.”
—Alasdair Chalmers MacIntyre (b. 1929)