Phase transition: Difference between revisions

From formulasearchengine
Jump to navigation Jump to search
en>Kmarinas86
No edit summary
en>Omnipaedista
 
(One intermediate revision by one other user not shown)
Line 1: Line 1:
{{Infobox Complexity Class
First In, 1St Out - Income Preserving Foodstuff Storage Group<br><br>
|class=EXPTIME, also called EXP
|image=[[File:Complexity subsets pspace.svg|200px]]
|long-name=Exponential time
|description=
|wheredefined=
|external-urls=[http://qwiki.stanford.edu/index.php/Complexity_Zoo:E#exp Complexity Zoo]
|complete-class=[[EXPTIME-complete]]
|complement-class=''self''
|proper-supersets=[[EXPSPACE]]
}}
:''"EXP" redirects here; for other uses, see [[exp]].''


In [[computational complexity theory]], the [[complexity class]] '''EXPTIME''' (sometimes called '''EXP''' or '''DEXPTIME''') is the [[Set (mathematics)|set]] of all [[decision problem]]s solvable by a [[deterministic Turing machine]] in [[big O notation|O]](2<sup>''p''(''n'')</sup>) time, where ''p''(''n'') is a polynomial function of ''n''.
This might look overwhelming specifically if you haven't even started out to retailer any meals or supplies Ebon Talifarro for your family members. There numerous motives you must have some form of food storage set up for your loved ones.<br><br>The finish outcome was a answer in which eggs would effectively have their pores sealed, thus sealing out oxygen and moisture. The deficiency of oxygen inhibited bacterial development, protecting against spoiling. It was said that "fresh" eggs could be kept up to two several years.<br><br>Vegetables or fruits that you have canned individually must probably be boiled for about 20 minutes just before consuming them. Cans of food that are developed commercially are normally subjected to special therapy to make sure that no microorganisms are able to enter and endure inside the can, but your very own canned food items do not bear this sort of a approach.<br><br>What should take the greatest treatment is packing meals. Naturally you know your automobile and its limitations for [https://www.diigo.com/profile/Ebontalifarro Ebon Talifarro]. When the vehicle is serviced, if there is a refrigerator or freezer incorporate them in the servicing. Wait around until the very last working day to pack and shop foodstuff. Pack food correctly.<br><br>You can obtain canned seafood of your option and blend it with bitter cream to provide as the base for a vegetable dip. Buy washed and minimize vegetables for straightforward dipping. Clams are a super Ebon Talifarro supply of iron; salmon a great supply of Omega 3 fatty acids. You actually can not go improper with your dip, however some herb mixes could be greater than other people.<br><br>Skip the RV. Instead of heading to this excursion on an RV, you can minimize gasoline and strength use substantially by bringing tents instead. Apart from becoming friendlier to the setting, tents also give a lot more enjoyment and problem to the vacation.<br><br>As we have experienced the great fortune to have been introduced up to recognize capitalism and democracy as if it is a presented. And close to the planet in too Ebon Talifarro a lot of locations it is not that however at all.<br><br>Overall, your blood will sluggish down and it will make your coronary heart [https://Www.Google.com/search?hl=en&gl=us&tbm=nws&q=function function] extremely tough to supply the nutrition that your entire body wants to numerous elements of your entire body. This problem frequently prospects to coronary heart attacks.<br><br>Look for indications that bears have been visiting the web site. Not all camper are vigilant in cleaning the camp site. A clean camp website will [http://Www.Google.co.uk/search?hl=en&gl=us&tbm=nws&q=minimize&gs_l=news minimize] the smell of foodstuff, but the last factor you want to do is set up camp in a spot the bears are currently captivated to.<br><br>To get the most recent updates from Atlanta Holistic Overall health Examiner Tina Ranieri 'click' the subscribe button earlier mentioned. To view her body of posts 'click' Tina Ranieri, Countrywide Holistic Overall health Examiner, or Atlanta Fishing Examiner.
 
In terms of [[DTIME]],
 
:<math> \mbox{EXPTIME} = \bigcup_{k \in \mathbb{N} } \mbox{ DTIME } \left( 2^{ n^k } \right) . </math>
 
We know
 
:[[P (complexity)|P]] <math>\subseteq</math> [[NP (complexity)|NP]] <math>\subseteq</math> [[PSPACE]] <math>\subseteq</math> EXPTIME <math>\subseteq</math> [[NEXPTIME]] <math>\subseteq</math> [[EXPSPACE]]
 
and also, by the [[time hierarchy theorem]] and the [[space hierarchy theorem]], that
 
:P <math>\subsetneq</math> EXPTIME{{nbsp|2}} and{{nbsp|2}} NP <math>\subsetneq</math> NEXPTIME{{nbsp|2}} and{{nbsp|2}} PSPACE <math>\subsetneq</math> EXPSPACE
 
so at least one of the first three inclusions and at least one of the last three inclusions must be proper, but it is not known which ones are. Most experts{{Who|date=December 2010}} believe all the inclusions are proper. It's also known that if {{nowrap|[[P = NP problem|P = NP]]}}, then {{nowrap|EXPTIME {{=}} [[NEXPTIME]]}}, the class of problems solvable in exponential time by a [[nondeterministic Turing machine]].<ref>{{cite book| author = Christos Papadimitriou| title = Computational Complexity| publisher = Addison-Wesley| year = 1994| isbn = 0-201-53082-1| authorlink = Christos Papadimitriou}} Section 20.1, page 491.</ref> More precisely, '''EXPTIME''' ≠ '''NEXPTIME''' if and only if there exist [[sparse language]]s in '''NP''' that are not in '''P'''.<ref>Juris Hartmanis, Neil Immerman, Vivian Sewelson. Sparse Sets in NP-P: EXPTIME versus NEXPTIME. ''Information and Control'', volume 65, issue 2/3, pp.158–181. 1985. [http://portal.acm.org/citation.cfm?id=808769 At ACM Digital Library]</ref>
 
EXPTIME can also be reformulated as the space class [[APSPACE]], the problems that can be solved by an [[alternating Turing machine]] in polynomial space. This is one way to see that PSPACE <math>\subseteq</math> EXPTIME, since an alternating Turing machine is at least as powerful as a deterministic Turing machine.<ref>Papadimitriou (1994), section 20.1, corollary 3, page 495.</ref>
 
EXPTIME is one class in an [[exponential hierarchy]] of complexity classes with increasingly more complex oracles or quantifier alternations. The class [[2-EXPTIME]] is defined similarly to EXPTIME but with a [[Double exponential function|doubly exponential]] time bound <math>2^{2^n}</math>. This can be generalized to higher and higher time bounds.
 
==EXPTIME-complete==
A decision problem is EXPTIME-complete if it is in EXPTIME, and every problem in EXPTIME has a [[polynomial-time many-one reduction]] to it. In other words, there is a polynomial-time [[algorithm]] that transforms instances of one to instances of the other with the same answer. Problems that are EXPTIME-complete might be thought of as the hardest problems in EXPTIME. Notice that although we don't know if NP is equal to P or not, we do know that EXPTIME-complete problems are not in P; it has been proven that these problems cannot be solved in [[polynomial time]], by the [[time hierarchy theorem]].
 
In [[computability theory]], one of the basic undecidable problems is that of deciding whether a [[deterministic Turing machine]] (DTM) halts. One of the most fundamental EXPTIME-complete problems is a simpler version of this, which asks if a DTM halts in at most ''k'' steps. It is in EXPTIME because a trivial simulation requires O(''k'') time, and the input ''k'' is encoded using O(log ''k'') bits.<ref>{{cite web| author = Chris Umans| url = http://www.cs.caltech.edu/~umans/cs21/lec18.pdf| title = CS 21: Lecture 18 notes}} Slide 10.</ref> It is EXPTIME-complete because, roughly speaking, we can use it to determine if a machine solving an EXPTIME problem accepts in an exponential number of steps; it will not use more. The same problem with the number of steps written in unary is [[P-complete]].
 
Other examples of EXPTIME-complete problems include the problem of evaluating a position in [[generalized game|generalized]] [[chess]],<ref name="Fraenkel1981">{{cite journal| author = [[Aviezri Fraenkel]] and D. Lichtenstein| title = Computing a perfect strategy for n&times;n chess requires time exponential in n| journal = J. Comb. Th. A| issue = 31| year = 1981| pages = 199–214}}</ref> [[checkers]],<ref name="robson1984">{{cite journal| author = J. M. Robson| title = N by N checkers is Exptime complete| journal = SIAM Journal on Computing| volume = 13| issue = 2| pages = 252–267| year = 1984| doi = 10.1137/0213018}}</ref> or [[Go (board game)|Go]] (with Japanese ko rules).<ref>{{Cite book| author = J. M. Robson| chapter = The complexity of Go| title = Information Processing; Proceedings of IFIP Congress| year = 1983| pages = 413–417}}</ref> These games have a chance of being EXPTIME-complete because games can last for a number of moves that is exponential in the size of the board. In the Go example, the Japanese ko rule is sufficiently intractable to imply EXPTIME-completeness, but it is not known if the more tractable American or Chinese rules for the game are EXPTIME-complete.
 
By contrast, generalized games that can last for a number of moves that is polynomial in the size of the board are often [[PSPACE-complete]]. The same is true of exponentially long games in which non-repetition is automatic.
 
Another set of important EXPTIME-complete problems relates to [[succinct circuit]]s. Succinct circuits are simple machines used to describe some graphs in exponentially less space. They accept two vertex numbers as input and output whether there is an edge between them. For many natural [[P-complete]] graph problems, where the graph is expressed in a natural representation such as an [[adjacency matrix]], solving the same problem on a succinct circuit representation is EXPTIME-complete, because the input is exponentially smaller; but this requires nontrivial proof, since succinct circuits can only describe a subclass of graphs.<ref>Papadimitriou (1994), section 20.1, page 492.</ref>
 
==References==
{{Reflist}}
 
{{ComplexityClasses}}
 
[[Category:Complexity classes]]

Latest revision as of 06:38, 26 December 2014

First In, 1St Out - Income Preserving Foodstuff Storage Group

This might look overwhelming specifically if you haven't even started out to retailer any meals or supplies Ebon Talifarro for your family members. There numerous motives you must have some form of food storage set up for your loved ones.

The finish outcome was a answer in which eggs would effectively have their pores sealed, thus sealing out oxygen and moisture. The deficiency of oxygen inhibited bacterial development, protecting against spoiling. It was said that "fresh" eggs could be kept up to two several years.

Vegetables or fruits that you have canned individually must probably be boiled for about 20 minutes just before consuming them. Cans of food that are developed commercially are normally subjected to special therapy to make sure that no microorganisms are able to enter and endure inside the can, but your very own canned food items do not bear this sort of a approach.

What should take the greatest treatment is packing meals. Naturally you know your automobile and its limitations for Ebon Talifarro. When the vehicle is serviced, if there is a refrigerator or freezer incorporate them in the servicing. Wait around until the very last working day to pack and shop foodstuff. Pack food correctly.

You can obtain canned seafood of your option and blend it with bitter cream to provide as the base for a vegetable dip. Buy washed and minimize vegetables for straightforward dipping. Clams are a super Ebon Talifarro supply of iron; salmon a great supply of Omega 3 fatty acids. You actually can not go improper with your dip, however some herb mixes could be greater than other people.

Skip the RV. Instead of heading to this excursion on an RV, you can minimize gasoline and strength use substantially by bringing tents instead. Apart from becoming friendlier to the setting, tents also give a lot more enjoyment and problem to the vacation.

As we have experienced the great fortune to have been introduced up to recognize capitalism and democracy as if it is a presented. And close to the planet in too Ebon Talifarro a lot of locations it is not that however at all.

Overall, your blood will sluggish down and it will make your coronary heart function extremely tough to supply the nutrition that your entire body wants to numerous elements of your entire body. This problem frequently prospects to coronary heart attacks.

Look for indications that bears have been visiting the web site. Not all camper are vigilant in cleaning the camp site. A clean camp website will minimize the smell of foodstuff, but the last factor you want to do is set up camp in a spot the bears are currently captivated to.

To get the most recent updates from Atlanta Holistic Overall health Examiner Tina Ranieri 'click' the subscribe button earlier mentioned. To view her body of posts 'click' Tina Ranieri, Countrywide Holistic Overall health Examiner, or Atlanta Fishing Examiner.