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11.
Understanding the end state of black hole evaporation, the microscopic origin of black hole entropy, the information loss paradox, and the nature of the singularity arising in gravitational collapse - these are outstanding challenges for any candidate quantum theory of gravity. Recently, a midisuperspace model of quantum gravitational collapse has been solved using a lattice regularization scheme. It is shown that the mass of an eternal black hole follows the Bekenstein spectrum, and a related argument provides a fairly accurate estimate of the entropy. The solution also describes a quantized mass-energy distribution around a central black hole, which in the WKB approximation, is precisely Hawking radiation. The leading quantum gravitational correction makes the spectrum non-thermal, thus providing a plausible resolution of the information loss problem. 相似文献
12.
Hidetoshi Shimodaira 《Annals of the Institute of Statistical Mathematics》1997,49(3):395-410
The asymptotic error probability of Linhart's model selection test isevaluated, and compared with the nominal significance level. We examine thecase where the expected discrepancies of the candidate models from the truemodel are asymptotically equal. The local alternatives method is employed inthe limiting operation of the asymptotic evaluation. Although the errorprobability under the null hypothesis is actually shown to be equal to orless than the level for most situations, intolerable violations of the errorcontrol are observed for nested models: It is often erroneously concludedthat the smaller model is significantly better than the larger model. Toprevent this violation, a modification of Linhart's test statistic isproposed. The effectiveness of the proposed test is confirmed throughtheoretical analysis and numerical simulations. 相似文献
13.
Vijay Balasubramanian Donald Marolf Moshe Rozali 《General Relativity and Gravitation》2006,38(11):1529-1536
We argue that if black hole entropy arises from a finite number of underlying quantum states, then any particular such state
can be identified from infinity. The finite density of states implies a discrete energy spectrum, and, in general, such spectra
are non-degenerate except as determined by symmetries. Therefore, knowledge of the precise energy, and of other commuting
conserved charges, determines the quantum state. In a gravitating theory, all conserved charges including the energy are given
by boundary terms that can be measured at infinity. Thus, within any theory of quantum gravity, no information can be lost
in black holes with a finite number of states. However, identifying the state of a black hole from infinity requires measurements
with Planck scale precision. Hence observers with insufficient resolution will experience information loss.
First Award in the 2006 Essay Competition of the Gravity Research Foundation. 相似文献
14.
基于傅立叶变换轮廓术的物面相位提取 总被引:1,自引:0,他引:1
采用傅立叶变换轮廓术,针对基频提取的关键技术采用逐行傅立叶变换,准确提取基频信息的方法恢复相位信息.在此基础上,以未畸变条纹为基准,得出被测物体的真实位相值.该方法只需一幅条纹图,节约了测量时间.实验证明可实现无接触面型的自动传感. 相似文献
15.
Canonical correlation analysis based on information theory 总被引:2,自引:0,他引:2
In this article, we propose a new canonical correlation method based on information theory. This method examines potential nonlinear relationships between p×1 vector Y-set and q×1 vector X-set. It finds canonical coefficient vectors a and b by maximizing a more general measure, the mutual information, between aTX and bTY. We use a permutation test to determine the pairs of the new canonical correlation variates, which requires no specific distributions for X and Y as long as one can estimate the densities of aTX and bTY nonparametrically. Examples illustrating the new method are presented. 相似文献
16.
网络环境下会计信息系统的创新 总被引:2,自引:0,他引:2
黄垚 《宁波大学学报(理工版)》2003,16(2):186-189
从我国会计软件的发展历程及网络环境方面,对会计信息系统软件功能的创新、会计信息系统基本结构的创新作了分析和探讨,提出了会计软件未来发展与创新的基本思路和设想. 相似文献
17.
18.
Adam B. Levy 《Mathematical Programming》2007,110(3):615-639
Numerical methods for solving constrained optimization problems need to incorporate the constraints in a manner that satisfies
essentially competing interests; the incorporation needs to be simple enough that the solution method is tractable, yet complex
enough to ensure the validity of the ultimate solution. We introduce a framework for constraint incorporation that identifies
a minimal acceptable level of complexity and defines two basic types of constraint incorporation which (with combinations)
cover nearly all popular numerical methods for constrained optimization, including trust region methods, penalty methods,
barrier methods, penalty-multiplier methods, and sequential quadratic programming methods. The broad application of our framework
relies on addition and chain rules for constraint incorporation which we develop here. 相似文献
19.
关于非齐次m阶马氏信源的渐近均分割性 总被引:4,自引:0,他引:4
本文研究非齐次m阶马氏信源的渐近均分割性,首先我们得到关于此种信源m 1元函数的一类强极限定理,作为推论,得到关于任意非齐次m阶马氏信源状态和熵密度的几个极限定理,最后得到一类非齐次m阶马氏信源的渐近均分割性。 相似文献
20.