Tuesday, December 15, 2015 4:52:37 AM
Quantum Time Travel Paradox Solved: Study
December 12, 2015
http://www.theepochtimes.com/n3/1917938-quantum-time-travel-paradox-solved-study/ [with comments]
the study:
Replicating the benefits of Deutschian closed timelike curves without breaking causality
Deutschian timelike curves. (a) depicts a physical visualization of a CTC, where an object entering one mouth of a wormhole at some point tA may jump to a prior time tB (with respect to an chronology respecting observer) and interact with its past self via some unitary U. (b) In the special case where no interaction occurs, we obtain an open timelike curve. This naturally occurs, for example, in instances where the wormhole mouths are spatially separated.
Published online: 24 November 2015
Abstract
In general relativity, closed timelike curves can break causality with remarkable and unsettling consequences. At the classical level, they induce causal paradoxes disturbing enough to motivate conjectures that explicitly prevent their existence. At the quantum level such problems can be resolved through the Deutschian formalism, however this induces radical benefits—from cloning unknown quantum states to solving problems intractable to quantum computers. Instinctively, one expects these benefits to vanish if causality is respected. Here we show that in harnessing entanglement, we can efficiently solve NP-complete problems and clone arbitrary quantum states—even when all time-travelling systems are completely isolated from the past. Thus, the many defining benefits of Deutschian closed timelike curves can still be harnessed, even when causality is preserved. Our results unveil a subtle interplay between entanglement and general relativity, and significantly improve the potential of probing the radical effects that may exist at the interface between relativity and quantum theory.
http://www.nature.com/articles/npjqi20157 [the complete study, open access]
(linked in) http://investorshub.advfn.com/boards/read_msg.aspx?message_id=112469581 and preceding and following
December 12, 2015
http://www.theepochtimes.com/n3/1917938-quantum-time-travel-paradox-solved-study/ [with comments]
the study:
Replicating the benefits of Deutschian closed timelike curves without breaking causality
Deutschian timelike curves. (a) depicts a physical visualization of a CTC, where an object entering one mouth of a wormhole at some point tA may jump to a prior time tB (with respect to an chronology respecting observer) and interact with its past self via some unitary U. (b) In the special case where no interaction occurs, we obtain an open timelike curve. This naturally occurs, for example, in instances where the wormhole mouths are spatially separated.
Published online: 24 November 2015
Abstract
In general relativity, closed timelike curves can break causality with remarkable and unsettling consequences. At the classical level, they induce causal paradoxes disturbing enough to motivate conjectures that explicitly prevent their existence. At the quantum level such problems can be resolved through the Deutschian formalism, however this induces radical benefits—from cloning unknown quantum states to solving problems intractable to quantum computers. Instinctively, one expects these benefits to vanish if causality is respected. Here we show that in harnessing entanglement, we can efficiently solve NP-complete problems and clone arbitrary quantum states—even when all time-travelling systems are completely isolated from the past. Thus, the many defining benefits of Deutschian closed timelike curves can still be harnessed, even when causality is preserved. Our results unveil a subtle interplay between entanglement and general relativity, and significantly improve the potential of probing the radical effects that may exist at the interface between relativity and quantum theory.
http://www.nature.com/articles/npjqi20157 [the complete study, open access]
(linked in) http://investorshub.advfn.com/boards/read_msg.aspx?message_id=112469581 and preceding and following
Greensburg, KS - 5/4/07
"Eternal vigilance is the price of Liberty."
from John Philpot Curran, Speech
upon the Right of Election, 1790
F6
Join the InvestorsHub Community
Register for free to join our community of investors and share your ideas. You will also get access to streaming quotes, interactive charts, trades, portfolio, live options flow and more tools.
