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THE BLACK HOLE WARS Investigating paradoxes that revolve around black holes.
THE BLACK HOLE WARS
Investigating paradoxes that revolve around black holes.
TOPICS
● What is a black hole
● Bekenstein and Hawking's contributions
● The Information Paradox.
● Leonard Susskind and Gerard't Hooft
● Resolution?
WHAT IS A BLACK HOLE?
Credit: NewsDiscovery.com
EINSTEIN'S WORK● Black holes were initially predicted by Einstein's
theory of general relativity.
Image credit: Nasa.gov
BLACK HOLE PROPERTIES?
● Massive star collapses
● Gravitational forces warp space-time and are so large that they crush the center into what is known as a singularity.
● “Place where space and time come to an end.” -Stephen Hawking.
● Event horizon.
● Cross the event horizon nothing can escape, not even light.
TWO KNOWN TYPES
● Steller black holes
● Supermassive black holes
BEKENSTEIN'S CONTRIBUTIONS
● In 1972 Jacob Bekenstein suggests that black holes must have entropy.
● Total information is proportional to it's area.
HAWKING'S CONTRIBUTIONS
● If a black hole has entropy, it must have a temperature.
● The result was Stephen Hawkings famous equation for entropy of a black hole.
HAWKING'S CONTRIBUTIONS
● If it has a temperature, this must mean it is radiating energy and will eventually evaporate and dissapear.
● Information is lost?
● The Information Paradox.
INFORMATION PARADOX
● Contradicts one of the most fundemental principles in physics.
● Given the conditions of a system at a given point in time, we should be able to look back in time and understand what occurred prior to the present state.
● Causality
INFORMATION
Image credit: theguardian.com
HOW DO WE FIX THIS?
● The answer would come as a result of looking at a contradiction that occurs at the edge of a black hole (event horizon).
● Image credit: daviddarling.info
DEAD …...AND ALIVE?
● What occurs when falling into a black hole is completely dependent on where the observer is.
Image credit: snc.edu
LEONARD SUSSKIND AND GERARD'T HOOFT
● The person entering the black hole has his information smeared onto the event horizon, so that it appears to dissintigrate.
● The person still thinks they are in tact.
● Projector effect.
● Information remains stretched on the edge of a black hole, is not destroyed and is still retrievable.
HAWKING'S RESPONSE
● In 2004 at a conference in Dublin, Stephen Hawking admits that he was wrong.
● However, he claims that Susskind wasn't right either.
CONCLUSION
● Leonard Susskind and Herard't Hooft are currently working on theory known as the holographic principle.
● Stephen Hawking formulates a new theory involving the sum of all histories.
● Although the information paradox was seemingly resolved the a battle continues between competing theories.
REFERENCES
● DeGrasse Tyson, Neil (2007). Death By Black Hole, New York, NY: W.W. Norton & Company Inc.
● Susskind, Leonard (2008). The Black Hole Wars, Stanford, CA: Little, Brown and Company
● Thorne, Kip S. (1994). Black Holes & Time Warps, New York, NY: W.W. Norton & Company Inc.
● Schroeder, Daniel V.(2000). Thermal Physics, Addison Wesley Longman.
