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YANGZL

金虫 (小有名气)

[交流] “P对NP(P versus NP, P vs NP)”问题的描述、难度、可能的答案

“P对NP(P versus NP, P vs NP)”问题的描述、难度、可能的答案
  
关键词:P对NP,P versus NP,P vs NP,the Millennium Problems,Clay Mathematics Institute
   
      “The P versus NP problem is to determine whether every language accepted by some nondeterministic algorithm in polynomial time is also accepted by some (deterministic) algorithm in polynomial time.” [1], now it becomes a famous mathematical fundamental problem, though it was being a hard open problem in the field of computational complexity theory in the theoretical computer science since the early 1970’s [2]. “P vs NP Problem” or “P versus NP problem” becomes one of the most famous mathematical problems after the seven Millennium Problems released by Clay Mathematics Institute in 2000 [3]. Before this, in 1998, Steve Smale listed it as the third problem in his 18 great problems of the 21th century, i.e, “Problem 3: Does P=NP?” [4]. After this, in 2005, Science magazine listed it as the 19th question of its top 25 of the 125 big questions face scientific inquiry over the next quarter-century, i.e., “What are the limits of conventional computing?” [5].
      P≠NP is the mainstream perspective up to now. In 2002, a total of 100 people poll gave the following statistics [6]:
“ 1. 61 thought P≠NP.
2. 9 thought P=NP.
3. 4 thought that it is independent. While no particular axiom system was mentioned, I assume they think it is independent of ZFC.
4. 3 just stated that it is NOT independent of Primitive Recursive Arithmetic.
5. 1 said it would depend on the model.
6. 22 offered no opinion.”
About 6000 papers each year discuss the “NP-complete” or “P vs NP” [7], the recent reviews and papers can see [8-12], et al.
   
参考文献:
[1] COOK S. The P versus NP Problem, official problem description, [EB/OL]. http://www.claymath.org/millennium/P_vs_NP/pvsnp.pdf
[2] 中国大百科全书•电子学与计算机[M]. 北京: 中国大百科全书出版社, 1986.
Encyclopaedia of China • Electronics and computer [M]. Beijing: Encyclopaedia of China Publishing House, 1986. (in chinese)   http://202.112.118.40:918/web/index.htm
[3] THE CLAY MATHEMATICS INSTITUTE. P vs NP Problem
[EB/OL]. http://www.claymath.org/millennium/P_vs_NP/.
[4] SMALE S. Mathematical problems for the next century [J]. Mathematical Intelligencer, 1998, 20(2): 7-15.
[5] SEIFE C. What are the limits of conventional computing? [J]. Science, 2005, 309(5731): 96.
[6] GASARCH W I. The P=?NP poll [J]. SIGACT News, 2002, 33(2): 34-47.
[7] ALLENDER E. A status report on the P Versus NP question [J]. Advances in Computers, 2009, 77: 117-147.
[8] FORTNOW L. The Status of the P versus NP Problem [J]. Communications of the ACM, 2009, 52(9): 78-86.
[9] COOK S. The importance of the P versus NP question [J]. Journal of the ACM, 2003, (50)1: 27-29.
[10] GASSNER C. Oracles and relativizations of the P =? NP question for several structures [J]. Journal of Universal Computer Science, 2009, 15(6): 1186-1205.
[11] MANEA F, MARGENSTERN M, MITRANA V, PEREZ-JIMENEZ MJ. A new characterization of NP, P, and PSPACE with accepting hybrid networks of evolutionary processors [J]. Theory of Computing Systems, 2010, 46(2): 174-192.
[12] MUKUND M. NP-Completeness not the same as separating P from NP [J]. Communications of the ACM, 2009, 52(4): 9-9.
[13] KURATOWSKI K, MOSTOWSKI A. Set theory [M]. Amsterdam: North-Holland Publishing Company, 1976.
[14] HAZEWINKEL M. Encyclopaedia of mathematics: an updated and annotated translation of the Soviet “Mathematical encyclopaedia”[M]. Dordrecht: Kluwer Academic Publishers, 2001.  《苏联数学百科全书》,http://eom.springer.de/
[15] HOPCROFT J E, MOTWANI R M, ULLMAN J D. Introduction to automata theory, languages, and computation (Third edition) [M]. New Jersey: Addison Wesley, 2006.
[16] GAREY M R, JOHNSON D S. Computers and Intractability: A Guide to the Theory of NP-Completeness [M]. New York: W. H. Freeman, 1979.
[17] Nondeterministic Turing Machine [EB/OL]. http://mathworld.wolfram.com/NondeterministicTuringMachine.html
[18] CHAITIN G J. Information-theoretic computational complexity [J]. IEEE Transactions on Information Theory, 1974, 20(1): 10-15.
[19] 中国大百科全书•数学[M]. 北京: 中国大百科全书出版社, 1988.
Encyclopaedia of China • Mathematics [M]. Beijing: Encyclopaedia of China Publishing House, 1988. (in chinese)   http://202.112.118.40:918/web/index.htm
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YANGZL

金虫 (小有名气)

一点新的思考:
    根据《概率论》里的中心极限定理,用取值都为正数的不同的“独立同分布”均匀分布随机数(都是正数)作为“完全图”上边的权重。
    当完全图的阶数越来越大时,汉密尔顿回路的总权重渐进正态分布:即不同汉密尔顿回路之间的总权重,几乎不能用确定型函数相互构造出。必须以“概率1”检查所有的汉密尔顿回路总权重。
真傻(求真)
2楼2021-07-23 01:15:52
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YANGZL

金虫 (小有名气)

引用回帖:
2楼: Originally posted by YANGZL at 2021-07-23 01:15:52
一点新的思考:
    根据《概率论》里的中心极限定理,用取值都为正数的不同的“独立同分布”均匀分布随机数(都是正数)作为“完全图”上边的权重。
    当完全图的阶数越来越大时,汉密尔顿回路的总权重渐进正态 ...

有些概率分布,如
Weibull Distribution
Exponential distribution
Logarithmic Distribution
Log-normal Distribution
自变量取值都是正的实数。
   
根据Central limit theorem,当
sums or other functions of a large number of independent or weakly-dependent random variables have a probability distribution close to the normal distribution.
当项数越来越大时,趋向于正态分布。
真傻(求真)
3楼2021-07-23 02:08:43
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