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= = White wins = =
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= = = White wins with 1.e4 = = =
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Although it is very much a minority view , three prominent twentieth @-@ century masters claimed that White 's advantage should or may be decisive with best play . Weaver Adams , then one of the leading American masters , was the best @-@ known proponent of this view , which he introduced in his 1939 book White to Play and Win , and continued to expound in later books and articles until shortly before his death in 1963 . Adams opined that 1.e4 was White 's strongest move , and that if both sides played the best moves thereafter , " White ought to win . " Adams ' claim was widely ridiculed , and he did not succeed in demonstrating the validity of his theory in tournament and match practice . The year after his book was published , at the finals of the 1940 U.S. Open tournament , he scored only one draw in his four games as White , but won all four of his games as Black . Adams also lost a match to IM I.A. Horowitz , who took the black pieces in every game .
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According to Sveshnikov , Vsevolod Rauzer , a leading Soviet player and theoretician during the 1930s , likewise " claimed in the [ 1930s ] : ' 1.e4 — and White wins ! ' and he managed to prove it quite often " .
| 7a822ca9f6261eccb75c0f0c6aa0b631 | 6,176 |
= = = White wins with 1.d4 = = =
| c537c271adc5b4848378f6f811d6c059 | 6,178 |
More recently , IM Hans Berliner , a former World Champion of Correspondence Chess , claimed in his 1999 book The System that 1.d4 gives White a large , and possibly decisive , advantage . Berliner asserted that with best play White wins against the Grünfeld Defense , the Modern Benoni , the Benko Gambit and other ( unnamed ) " major defences " , and achieves at least a large advantage in many lines of the Queen 's Gambit Declined . However , he allowed that , " It is possible that the rules of chess are such that only some number of plausible @-@ appearing defences to 1.d4 can be refuted . " Berliner wrote that Adams ' " theories , though looked upon with scorn by most top chess players , made an immediate and lasting impression on me . Weaver W. Adams was the first person I met who actually had theories about how chess should be played . "
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Berliner 's thesis , like Adams ' , has been sharply criticized .
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= = Modern perspectives = =
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As explained below , chess theorists in recent decades have continued to debate the size and nature of White 's advantage , if any . Apart from Berliner , they have rejected the idea that White has a forced win from the opening position . Many also reject the traditional paradigm that Black 's objective should be to neutralize White 's initiative and obtain equality .
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= = = White has an enduring advantage = = =
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In 2004 , GM Larry Kaufman expressed a more nuanced view than Adams and Berliner , arguing that the initiative stemming from the first move can always be transformed into some sort of enduring advantage , albeit not necessarily a decisive one . Kaufman writes , " I don 't believe that White has a forced win in Chess . I do however believe that with either 1.e4 or 1.d4 , White should be able to obtain some sort of advantage that persists into the endgame . If chess were scored like boxing , with drawn games awarded by some point system to the player ( if any ) who came ' closer ' to winning , then I believe White would indeed have a forced win in theory . "
| d4c8d0ab429dca3f7ff33a9be6bbda33 | 6,189 |
= = = Black is OK ! = = =
| baeed2134921cdfba577207ec6f69c85 | 6,191 |
Starting in 1988 , Adorján has argued in a series of books and magazine articles that " Black is OK ! " Alone amongst modern writers , Adorján claims that White starts the game with essentially no advantage . He writes , " In my opinion , the only obvious advantage for White is that if he or she plays for a draw , and does so well , then Black can hardly avoid this without taking obvious risks . " Adorján goes so far as to claim that , " The tale of White 's advantage is a delusion , belief in it is based on mass psychosis . " Rowson writes that Adorján 's " contention is one of the most important chess ideas of the last two decades ... because it has shaken our assumption that White begins the game with some advantage , and revealed its ideological nature " . However , Rowson rejects Adorján 's claim that White has essentially no advantage , reasoning that " ' White is better ' and ' Black is OK ' need not be mutually exclusive claims " .
| 3ba60a35834b6a2412a171c39673d2d9 | 6,193 |
In one of Adorján 's books , GM Lajos Portisch opined that " at least two @-@ thirds of all ' tested ' openings give White an apparent advantage . " According to Portisch , for Black , " The root of the problem is that very few people know which are the openings where Black is really OK . Those who find these lines have nothing to fear , as Black is indeed OK , but only in those variations ! " Rowson considers this an important point , noting that " 1.d4 players struggle to get anywhere against main @-@ line Slavs and 1.e4 players find the Najdorf and Sveshnikov Sicilians particularly tough . "
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= = = Dynamism = = =
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Modern writers often think of Black 's role in more dynamic terms than merely trying to equalize . Rowson writes that " the idea of Black trying to ' equalize ' is questionable . I think it has limited application to a few openings , rather than being an opening prescription for Black in general . " Evans wrote that after one of his games against Fischer , " Fischer confided his ' secret ' to me : unlike other masters , he sought to win with the Black pieces from the start . The revelation that Black has dynamic chances and need not be satisfied with mere equality was the turning point in his career , he said . " Likewise , Watson surmised that Kasparov , when playing Black , bypasses the question of whether White has an opening advantage " by thinking in terms of the concrete nature of the dynamic imbalance on the board , and seeking to seize the initiative whenever possible " . Watson observes that " energetic opening play by Black may ... lead to a position so complex and unclear that to speak of equality is meaningless . Sometimes we say ' dynamically balanced ' instead of ' equal ' to express the view that either player is as likely as the other to emerge from complications with an advantage . This style of opening play has become prevalent in modern chess , with World Champions Fischer and Kasparov as its most visible practitioners . "
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Modern writers also question the idea that White has an enduring advantage . Suba , in his influential 1991 book Dynamic Chess Strategy , rejects the notion that the initiative can always be transformed into an enduring advantage . He contends that sometimes the player with the initiative loses it with no logical explanation , and that , " Sometimes you must lose it , just like that . If you try to cling to it , by forcing the issue , your dynamic potential will become exhausted and you won 't be able to face a vigorous counter @-@ attack . " Rowson and Watson concur . Watson also observes , " Because of the presumption of White being better , the juncture of the game at which Black frees his game or neutralizes White 's plans has often been automatically assumed to give him equality , even though in dynamic openings , the exhaustion of White 's initiative very often means that Black has seized it with advantage . "
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= = = Countervailing advantages = = =
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Rowson argues that both White and Black have certain advantages :
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= = = = White 's advantages = = = =
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According to Rowson , White 's first advantage is that , " The advantage of the first move has some similarities with the serve in tennis in that White can score an ' ace ' ( for instance with a powerful opening novelty ) , he has more control over the pace and direction of the game , and he has a ' second serve ' in that when things go wrong his position is not usually losing . " Second , White begins the game with some initiative , although Rowson regards this as a psychological rather than a positional advantage , " and whether it leads to a positional advantage depends on the relative skill of the players . " Third , some players are able to use the initiative to " play a kind of powerful ' serve and volley ' chess in which Black is flattened with a mixture of deep preparation and attacking prowess . " Fourth , " If White wants to draw , it is often not so easy for Black to prevent this . This advantage is particularly acute in cases where there is a possible threefold repetition , because White can begin the repetition without committing to a draw and Black has to decide whether to deviate before he knows whether White is bluffing . "
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Rowson cites as an example of the last phenomenon the well @-@ regarded Zaitsev Variation of the Ruy Lopez . After 1.e4 e5 2.Nf3 Nc6 3.Bb5 a6 4.Ba4 Nf6 5 @.@ 0 @-@ 0 Be7 6.Re1 b5 7.Bb3 0 @-@ 0 8.c3 d6 9.h3 Bb7 10.d4 Re8 ( initiating the Zaitsev Variation ) , White can repeat moves once with 11.Ng5 Rf8 12.Nf3. This puts Black in an awkward situation , since he must either ( a ) insist on the Zaitsev with 12 ... Re8 , which allows White to choose whether to draw by threefold repetition with 13.Ng5 Rf8 14.Nf3 , or play on with a different move , or ( b ) play a different ( and possibly inferior ) variation by playing something other than 12 ... Re8 .
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= = = = Black 's advantages = = = =
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Rowson argues that Black also has several advantages . First , " White 's alleged advantage is also a kind of obligation to play for a win , and Black can often use this to his advantage . " Second , " White 's ' extra move ' can be a burden , and sometimes White finds himself in a mild form of zugzwang ( ' Zugzwang Lite ' ) . " Third , although White begins the game with the initiative , if " Black retains a flexible position with good reactive possibilities , this initiative can be absorbed and often passes over to Black . " Fourth , " The fact that White moves before Black often gives Black useful information " . Suba likewise argues that White 's advantage is actually less than a move , since White must tip his hand first , allowing Black to react to White 's plans . Suba writes , " In terms of the mathematical games theory , chess is a game of complete information , and Black 's information is always greater — by one move ! "
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Rowson also notes that Black 's chances increase markedly by playing good openings , which tend to be those with flexibility and latent potential , " rather than those that give White fixed targets or that try to take the initiative prematurely . " He also emphasizes that " White has ' the initiative ' , not ' the advantage ' . Success with Black depends on seeing beyond the initiative and thinking of positions in terms of ' potential ' . " These ideas are exemplified by the Hedgehog , a dynamic modern system against the English Opening that can arise from various move orders . A typical position arises after 1.c4 c5 2.Nf3 Nf6 3.g3 b6 4.Bg2 Bb7 5 @.@ 0 @-@ 0 e6 6.Nc3 Be7 7.d4 cxd4 8.Qxd4 d6 9.e4 a6 . White has a spatial advantage , while Black often maneuvers his pieces on the last two ranks of the board , but White " has to keep a constant eye on the possible liberating pawn thrusts ... b5 and ... d5 . " Watson remarks , " Black 's goal is to remain elastic and flexible , with many options for his pieces , whereas White can become paralyzed at some point by the need to protect against various dynamic pawn breaks . " He also observes that , " White tends to be as much tied up by Black 's latent activity as Black himself is tied up by White 's space advantage . " Moreover , attempts by White to overrun Black 's position often rebound disastrously . An example of this is the following grandmaster game :
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Lev Polugaevsky – Ľubomír Ftáčnik , Lucerne Olympiad 1982 : 1 . Nf3 Nf6 2 @.@ c4 c5 3 . Nc3 e6 4 @.@ g3 b6 5 . Bg2 Bb7 6 . 0 @-@ 0 Be7 7 @.@ d4 cxd4 8 . Qxd4 d6 9 . Rd1 a6 10 @.@ b3 Nbd7 11 @.@ e4 Qb8 12 . Bb2 0 @-@ 0 Suba wrote of a similar Hedgehog position , " White 's position looks ideal . That 's the naked truth about it , but the ' ideal ' has by definition one drawback — it cannot be improved . " 13 . Nd2 Rd8 14 @.@ a4 Qc7 15 . Qe3 Rac8 16 . Qe2 Ne5 17 @.@ h3 ? According to Ftáčnik , 17.f4 Neg4 18.Rf1 is better. h5 ! 18 @.@ f4 Ng6 19 . Nf3 Now Black breaks open the position in typical Hedgehog fashion. d5 ! 20 @.@ cxd5 ? ! Ftáčnik considers 20.e5 or 20.exd5 preferable. h4 ! 21 . Nxh4 Nxh4 22 @.@ gxh4 Qxf4 23 @.@ dxe6 fxe6 24 @.@ e5 ? Ftáčnik recommends instead 24.Rxd8 Rxd8 25.Rd1. Bc5 + 25 . Kh1 Nh5 ! 26 . Qxh5 Qg3 27 . Nd5 Other moves get mated immediately : 27.Bxb7 Qh3 # ; 27.Qe2 Qxh3 # ; 27.Qg4 Bxg2 # . Rxd5 28 . Rf1 Qxg2 + ! 29 . Kxg2 Rd2 + If 30.Kg3 ( the only legal response to the double check ) , Rg2 + 31.Kf4 Rf8 + forces mate . 0 – 1
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An examination of reversed and symmetrical openings illustrates White 's and Black 's respective advantages :
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= = = = = Reversed openings = = = = =
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In a " reversed opening " , White plays an opening typically played by Black , but with colors reversed and thus an extra tempo . Evans writes of such openings , " If a defense is considered good for Black , it must be even better for White with a move in hand . " Former World Champion Mikhail Botvinnik reportedly expressed the same view . Watson questions this idea , citing Suba 's thesis that Black , by moving second , has more complete information than White . He writes , " everyone has such difficulties playing as White against a Sicilian Defence ( 1.e4 c5 ) , but ... leading masters have no qualms about answering 1.c4 with 1 ... e5 . " To explain this paradox , Watson discusses several different reversed Sicilian lines , showing how Black can exploit the disadvantages of various " extra " moves for White . He concludes , " The point is , Black 's set @-@ up in the Sicilian is fine as a reactive system , but not worth much when trying to claim the initiative as White . This is true because Black is able to react to the specific plan White chooses ; in Suba 's terms , his information is indeed a move greater ! Furthermore , he is able to take advantage of dead equal positions which White ( hoping to retain the advantage of the first move ) would normally avoid . "
| 2c12fa8934c724a9c96716e1aad4a4b6 | 6,219 |
Watson also observes , " Similarly , the Dutch Defence looks particularly sterile when White achieves the reversed positions a tempo up ( it turns out that he has nothing useful to do ! ) ; and indeed , many standard Black openings are not very inspiring when one gets them as White , tempo in hand . " GM Alex Yermolinsky likewise notes that GM Vladimir Malaniuk , a successful exponent of the Leningrad Dutch ( 1.d4 f5 2.g3 g6 ) at the highest levels , " once made a deep impression on me by casually dismissing someone 's suggestion that he should try 1.f4 as White . He smiled and said , ' That extra move 's gonna hurt me . ' "
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Yermolinsky also agrees with Alekhine 's criticism of 1.g3 e5 2.Nf3 , a reversed Alekhine 's Defense , in Réti – Alekhine , Baden @-@ Baden 1925 , writing that Alekhine " understood the difference in opening philosophies for White and Black , and realized they just can 't be the same ! White is supposed to try for more than just obtaining a comfortable game in reversed colour opening set @-@ ups , and , as the statistics show — surprisingly for a lot of people , but not for me — White doesn 't even score as well as Black does in the same positions with his extra tempo and all . " Howard Staunton , generally considered to have been the strongest player in the world from 1843 to 1851 , made a similar point over 160 years ago , writing that Owen 's Defense ( 1.e4 b6 ) is playable for Black , but that 1.b3 is inferior to " the more customary [ first ] moves , from its being essentially defensive " . The current view is that Owen 's Defense is slightly better for White , while 1.b3 is playable but less likely to yield an opening advantage than 1.e4 or 1.d4.
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Watson concludes that ( a ) " most moves have disadvantages as well as advantages , so an extra move is not always an unqualified blessing " ; ( b ) " with his extra information about what White is doing , Black can better react to the new situation " ; and ( c ) because a draw is likely to be more acceptable to Black than to White , White is apt to avoid lines that allow drawish simplifications , while Black may not object to such lines .
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= = = = = Symmetrical openings = = = = =
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Rowson writes that " in general one would assume that whatever advantage White has would be revealed most clearly in symmetrical positions . " Accordingly , Watson , Suba , Evans , and the eminent player and theorist Aron Nimzowitsch ( 1886 – 1935 ) have all argued that it is in Black 's interest to avoid symmetry . Nonetheless , even symmetrical opening lines sometimes illustrate the tenuous nature of White 's advantage , in several respects .
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It is often difficult for White to prove an advantage in symmetrical opening lines . As GM Bent Larsen wrote , annotating a game that began 1.c4 c5 2.b3 b6 , " In symmetrical openings , White has a theoretical advantage , but in many of them it is only theoretical . " GM Andrew Soltis wrote in 2008 that he hates playing against the symmetrical Petroff 's Defense ( 1.e4 e5 2.Nf3 Nf6 ) , and accordingly varies with 2.Nc3 , the Vienna Game . However , there too he has been unable to find a way to an advantage after the symmetrical 2 ... Nc6 3.g3 g6 4.Bg2 Bg7 , or after 3.Nf3 Nf6 ( transposing to the Four Knights Game ) 4.Bb5 Bb4 5 @.@ 0 @-@ 0 0 @-@ 0 6.d3 d6 7.Bg5 Bg4 8.Nd5 Nd4 9.Nxb4 Nxb5 , or 7.Ne2 Ne7 8.c3 Ba5 9.Ng3 c6 10.Ba4 Ng6 11.d4 d5 , when 12.exd5 ? ! e4 ! may even favor Black .
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Moreover , symmetrical positions may be disadvantageous to White in that he has to commit himself first . Watson notes that it is even difficult for White to play noncommittally in a symmetrical position , since almost every move has certain drawbacks . Fischer once went so far as to claim that after 1.Nf3 Nf6 2.g3 g6 3.Bg2 Bg7 4 @.@ 0 @-@ 0 0 @-@ 0 5.d3 d6 ( Reinhard – Fischer , Western Open 1963 ) , " ' Believe it or not , ' Black stands better ! Now , whatever White does , Black will vary it and get an asymmetrical position and have the superior position due to his better pawn structure ! " However , GM Paul Keres responded in CHESS magazine , " We just don 't believe it ! " In symmetrical positions , as the Hodgson – Arkell and Portisch – Tal games discussed below illustrate , Black can continue to imitate White as long as he finds it feasible and desirable to do so , and deviate when that ceases to be the case .
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Further , a particular extra move is sometimes more of a liability than an asset . For example , Soltis notes that the Exchange French position arising after 1.e4 e6 2.d4 d5 3.exd5 exd5 4.Nf3 Nf6 " is pretty equal . " The same position , but with Black 's knight moved to e4 , arises in Petroff 's Defense after 1.e4 e5 2.Nf3 Nf6 3.Nxe5 d6 4.Nf3 Nxe4 5.d4 d5 . That position offers White better chances precisely because Black 's extra move ( ... Ne4 ) allows the advanced knight to become a target for attack .
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Finally , symmetrical positions may be difficult for the white player for psychological reasons . Watson writes that anyone who tries the Exchange French , " even if he thinks he is playing for a win , assume [ s ] a psychological burden . White has already ceded the advantage of the first move , and knows it , whereas Black is challenged to find ways to seize the initiative . " Two famous examples of White losses in the Exchange French are M. Gurevich – Short and Tatai – Korchnoi . In M. Gurevich – Short , a game between two of the world 's leading players , White needed only a draw to qualify for the Candidates Matches , while Black needed to win . Gurevich played passively and was outplayed by Short , who achieved the necessary win , qualified for the Candidates , and ultimately went on to challenge Kasparov for the World Championship . In Tatai – Korchnoi , the Italian IM fell victim to Korchnoi 's whirlwind mating attack , losing in just 14 moves .
| 44daafb4306573072760c13a51fc14ac | 6,230 |
Rowson gives the following example of Black outplaying White from the Symmetrical Variation of the English Opening . He remarks , " there is something compelling about Black 's strategy . He seems to be saying : ' I will copy all your good moves , and as soon as you make a bad move , I won 't copy you any more ! ' "
| 51081f5bc6a06c713f18b27a54dc46ff | 6,231 |
Hodgson – Arkell , Newcastle 2001 : 1 @.@ c4 c5 2 @.@ g3 g6 3 . Bg2 Bg7 4 . Nc3 Nc6 5 @.@ a3 a6 6 . Rb1 Rb8 7 @.@ b4 cxb4 8 @.@ axb4 b5 9 @.@ cxb5 axb5 Here Rowson remarks , " Both sides want to push their d @-@ pawn and play Bf4 / ... Bf5 , but White has to go first so Black gets to play ... d5 before White can play d4 . This doesn 't matter much , but it already points to the challenge that White faces here ; his most natural continuations allow Black to play the moves he wants to . I would therefore say that White is in ' Zugzwang Lite ' and that he remains in this state for several moves . " 10 . Nf3 d5 10 ... Nf6 11 @.@ 0 @-@ 0 0 @-@ 0 12.d3 d6 13.Bd2 Bd7 would transpose to the Portisch – Tal game below . 11 @.@ d4 Nf6 12 . Bf4 Rb6 13 . 0 @-@ 0 Bf5 14 . Rb3 0 @-@ 0 15 . Ne5 Ne4 16 @.@ h3 h5 ! ? Finally breaking the symmetry . 17 . Kh2 The position is still almost symmetrical , and White can find nothing useful to do with his extra move . Rowson whimsically suggests 17.h4 ! ? , forcing Black to be the one to break the symmetry . 17 ... Re8 ! Rowson notes that this is a useful waiting move , covering e7 , which needs protection in some lines , and possibly supporting an eventual ... e5 ( see Black 's twenty @-@ second move ) . White cannot copy it , since after 18.Re1 ? Nxf2 Black would win a pawn . 18 . Be3 ? ! Nxe5 ! 19 @.@ dxe5 Rc6 ! Rowson notes that with his more active pieces , " It looks like Black has some initiative . " If now 20.Nxd5 , Bxe5 " is at least equal for Black " . 20 . Nxb5 Bxe5 ! 20 ... Nxf2 ? 21.Qxd5 ! wins . 21 . Nd4 Bxd4 22 . Bxd4 e5 Rowson writes , " Now both sides have their trumps , but I think Black has some advantage , due to his extra central control , imposing knight and prospects for a kingside attack . " 23 @.@ b5 Rc8 24 . Bb2 d4 Now White has a difficult game : Rowson analyzes 25.e3 ? ! Nxg3 24.fxg3 Bc2 25.Qf3 Bxb3 26.exd4 Bc4 ! , winning ; 25.g4 hxg4 26.hxg4 Nxf2 ! 27.Rxf2 Bc2 , winning ; 25.Qe1 ! ? Rc2 ! with advantage ; and 25.f4 ( risky @-@ looking , but perhaps best ) Nc3 ! 26.Bxc3 dxc3 27.Qxd8 Rexd8 , and Black is better . 25 @.@ b6 ? Overlooking Black 's threat . 25 ... Nxf2 ! 26 . Qe1 If 26.Rxf2 , Bc2 forks White 's queen and rook . 26 ... Ne4 27 @.@ b7 Rb8 28 @.@ g4 hxg4 29 @.@ hxg4 Be6 30 . Rb5 Nf6 ! 31 . Rxf6 Qxf6 32 . Qg3 Bc4 33 @.@ g5 Qh8 + 0 – 1
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The opening of the following game between two world @-@ class players , another Symmetrical English , took a similar course :
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Lajos Portisch – Mikhail Tal , Candidates Match 1965 : 1 . Nf3 c5 2 @.@ c4 Nc6 3 . Nc3 Nf6 4 @.@ g3 g6 5 . Bg2 Bg7 6 . 0 @-@ 0 0 @-@ 0 7 @.@ d3 a6 8 @.@ a3 Rb8 9 . Rb1 b5 10 @.@ cxb5 axb5 11 @.@ b4 cxb4 12 @.@ axb4 d6 13 . Bd2 Bd7 Once again , White is on move in a symmetrical position , but it is not obvious what he can do with his first @-@ move initiative . Soltis writes , " It 's ridiculous to think Black 's position is better . But Mikhail Tal said it is easier to play . By moving second he gets to see White 's move and then decide whether to match it . " 14.Qc1 Here , Soltis writes that Black could maintain equality by keeping the symmetry : 14 ... Qc8 15.Bh6 Bh3 . Instead , he plays to prove that White 's queen is misplaced . 14 ... Rc8 ! 15.Bh6 Nd4 ! Threatening 16 ... Nxe2 + . 16.Nxd4 Bxh6 17.Qxh6 Rxc3 18.Qd2 Qc7 19.Rfc1 Rc8 Although the pawn structure is still symmetrical , Black 's control of the c @-@ file gives him the advantage . Black ultimately reached an endgame two pawns up , but White managed to hold a draw in 83 moves .
| 8a1f331534d24313d2188b40640dc4dd | 6,234 |
Tal himself lost a famous game as White from a symmetrical position in Tal – Beliavsky , USSR Championship 1974 .
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= = Tournament and match play = =
| 8cb73c46cb2e55d13b248c09b7178083 | 6,237 |
In chess tournaments and matches , the frequency with which each player receives white and black is an important consideration . In matches , the players ' colors in the first game are determined by drawing lots , and alternated thereafter . In round robin tournaments with an odd number of players , each player receives an equal number of whites and blacks ; with an even number of players , each receives one extra white or black . Where one or more players withdraws from the tournament , the tournament director may change the assigned colors in some games so that no player receives two more blacks than whites , or vice versa . The double @-@ round robin tournament is considered to give the most reliable final standings , since each player receives the same number of whites and blacks , and plays both White and Black against each opponent .
| 8dc0f48dc62660acff188c707faed3ac | 6,239 |
In Swiss system tournaments , the tournament director tries to ensure that each player receives , as nearly as possible , the same number of games as White and Black , and that the player 's color alternates from round to round . After the first round , the director may deviate from the otherwise prescribed pairings in order to give as many players as possible their equalizing or due colors . More substantial deviations are permissible to avoid giving a player two more blacks than whites ( for example , three blacks in four games ) than vice versa , since extra whites " cause far less player distress " than extra blacks , which impose " a significant handicap " on the affected player . Tournaments with an even number of rounds cause the most problems , since if there is a disparity , it is greater ( e.g. , a player receiving two whites and four blacks ) .
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= = Solving chess = =
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Endgame tablebases have solved a very limited area of chess , determining perfect play in a number of endgames , including all non @-@ trivial endgames with no more than six pieces or pawns ( including the two kings ) . Seven @-@ piece endgames were solved in 2012 and released as " Lomonosov tablebases " .
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Jonathan Rowson has speculated that " in principle it should be possible for a machine to ... develop 32 @-@ piece tablebases . This may take decades or even centuries , but unless runaway global warming or nuclear war gets in the way , I think it will eventually happen . " However , information theorist Claude Shannon argued that it is not feasible for any computer to actually do this . In his 1950 paper " Programming a Computer for Playing Chess " he writes :
| b14ae117743d617f55054c058ca507dd | 6,245 |
With chess it is possible , in principle , to play a perfect game or construct a machine to do so as follows : One considers in a given position all possible moves , then all moves for the opponent , etc . , to the end of the game ( in each variation ) . The end must occur , by the rules of the games after a finite number of moves ( remembering the 50 move drawing rule ) . Each of these variations ends in win , loss or draw . By working backward from the end one can determine whether there is a forced win , the position is a draw or is lost . It is easy to show , however , even with the high computing speed available in electronic calculators this computation is impractical . In typical chess positions there will be of the order of 30 legal moves . The number holds fairly constant until the game is nearly finished as shown ... by De Groot , who averaged the number of legal moves in a large number of master games . Thus a move for White and then one for Black gives about 103 possibilities . A typical game lasts about 40 moves to resignation of one party . This is conservative for our calculation since the machine would calculate out to checkmate , not resignation . However , even at this figure there will be 10120 variations to be calculated from the initial position . A machine operating at the rate of one variation per microsecond would require over 1090 years to calculate the first move !
| abe59245c64e490f7130a2f9b07c744d | 6,246 |
It is thus theoretically possible to " solve " chess , determining with certainty whether a perfectly played game should end in a win for White , a draw , or even a win for Black . However , according to Shannon the time frame required puts this possibility beyond the limits of any feasible technology .
| 2fb85ade63e2ec4582ebe644d6892020 | 6,247 |
Hans @-@ Joachim Bremermann , a professor of mathematics and biophysics at the University of California at Berkeley , further argued in a 1965 paper that the " speed , memory , and processing capacity of any possible future computer equipment are limited by certain physical barriers : the light barrier , the quantum barrier , and the thermodynamical barrier . These limitations imply , for example , that no computer , however constructed , will ever be able to examine the entire tree of possible move sequences of the game of chess . " Nonetheless , Bremermann did not foreclose the possibility that a computer would someday be able to solve chess . He wrote , " In order to have a computer play a perfect or nearly perfect game [ of chess ] it will be necessary either to analyze the game completely ... or to analyze the game in an approximate way and combine this with a limited amount of tree searching . ... A theoretical understanding of such heuristic programming , however , is still very much wanting . "
| 50921bb17678484fa392c016b41361ef | 6,248 |
Recent scientific advances have not significantly changed that assessment . The game of checkers was solved in 2007 , but it has roughly the square root of the number of positions in chess . Jonathan Schaeffer , the scientist who led the effort , said a breakthrough such as quantum computing would be needed before solving chess could even be attempted , but he does not rule out the possibility , saying that the one thing he learned from his 16 @-@ year effort of solving checkers " is to never underestimate the advances in technology " .
| ca1166d0e76b6cc68a7f532037241648 | 6,249 |
= = Quotation = =
| ee447e14ee15d64306adf4513f78a1b1 | 6,251 |
" You will win with either color if you are the better player , but it takes longer with Black . " – Isaac Kashdan
| d51c0f00596e69947f57abdb830e3c8e | 6,253 |
= Frederick Reines =
| b9a02f0fc019cd68df4863805da5976e | 6,256 |
Frederick Reines ( RYE @-@ ness ) ; ( March 16 , 1918 – August 26 , 1998 ) was an American physicist . He was awarded the 1995 Nobel Prize in Physics for his co @-@ detection of the neutrino with Clyde Cowan in the neutrino experiment . He may be the only scientist in history " so intimately associated with the discovery of an elementary particle and the subsequent thorough investigation of its fundamental properties " .
| 7c7b91189597c24592c63039293efaef | 6,258 |
A graduate of the Stevens Institute of Technology and New York University , Reines joined the Manhattan Project 's Los Alamos Laboratory in 1944 , working in the Theoretical Division in Richard Feynman 's group . He became a group leader there in 1946 . He participated in a number of nuclear tests , culminating in his becoming the director of the Operation Greenhouse test series in the Pacific in 1951 .
| 91d9bbdd84036e040dbf8972996670a5 | 6,259 |
In the early 1950s , working in Hanford and Savannah River Sites , Reines and Cowan developed the equipment and procedures with which they first detected the supposedly undetectable neutrinos in June 1956 . Reines dedicated the major part of his career to the study of the neutrino 's properties and interactions , which work would influence study of the neutrino for many researchers to come . This included the detection of neutrinos created in the atmosphere by cosmic rays , and the 1987 detection of neutrinos emitted from Supernova SN1987A , which inaugurated the field of neutrino astronomy .
| ef540851e9a4f7bb19442c745fced9fb | 6,260 |
= = Early life = =
| b536b642460eb47d0633950c6043cf5f | 6,262 |
Frederick Reines was born in Paterson , New Jersey , one of four children of Gussie ( Cohen ) and Israel Reines . His parents were Jewish emigrants from the same town in Russia , but only met in New York City , where they were later married . He had an older sister , Paula , who became a doctor , and two older brothers , David and William , who became lawyers . He said that his " early education was strongly influenced " by his studious siblings . He was the great @-@ nephew of the Rabbi Yitzchak Yaacov Reines , the founder of Mizrachi , a religious Zionist movement .
| 21f63e49a66696a6e11c785585a86457 | 6,264 |
The family moved to Hillburn , New York , where his father ran the general store , and he spent much of his childhood . He was an Eagle Scout . Looking back , Reines said : " My early childhood memories center around this typical American country store and life in a small American town , including Independence Day July celebrations marked by fireworks and patriotic music played from a pavilion bandstand . "
| 64eab2024cb8d4a65fe419e9c3078589 | 6,265 |
Reines sang in a chorus , and as a soloist . For a time he considered the possibility of a singing career , and was instructed by a vocal coach from the Metropolitan Opera who provided lessons for free because the family did not have the money for them . The family later moved to North Bergen , New Jersey , residing on Kennedy Boulevard and 57th Street . Because North Bergen did not have a high school , he attended Union Hill High School in Union Hill , New Jersey , from which he graduated in 1935 .
| 6317d915d70d58485f394c4411b888c7 | 6,266 |
From an early age , Reines exhibited an interest in science , and liked creating and building things . He later recalled that :
| f8fa5011128ec9b07d9a243414964c0c | 6,267 |
The first stirrings of interest in science that I remember occurred during a moment of boredom at religious school , when , looking out of the window at twilight through a hand curled to simulate a telescope , I noticed something peculiar about the light ; it was the phenomenon of diffraction . That began for me a fascination with light .
| 7ce88e9897b9e7390dac051d35a417a8 | 6,268 |
Ironically , Reines excelled in literary and history courses , but received average or low marks in science and math in his freshman year of high school , though he improved in those areas by his junior and senior years through the encouragement of a teacher who gave him a key to the school laboratory . This cultivated a love of science by his senior year . In response to a question seniors were asked about what they wanted to do for a yearbook quote , he responded : " To be a physicist extraordinaire . "
| 811951ea9eebfee9caf548fb5c2e350c | 6,269 |
Reines was accepted into the Massachusetts Institute of Technology , but chose instead to attend Stevens Institute of Technology in Hoboken , New Jersey , where he earned his Bachelor of Science ( B.S. ) degree in mechanical engineering in 1939 , and his Master of Science ( M.S. ) degree in mathematical physics in 1941 , writing a thesis on " A Critical Review of Optical Diffraction Theory " . He married Sylvia Samuels on August 30 , 1940 . They had two children , Robert and Alisa . He then entered New York University , where he earned his Doctor of Philosophy ( Ph.D. ) in 1944 . He studied cosmic rays there under Serge A. Korff , but wrote his thesis under the supervision of Richard D. Present on " Nuclear fission and the liquid drop model of the nucleus " . Publication of the thesis was delayed until after the end of World War II ; it appeared in Physical Review in 1946 .
| 65ab86c31e32cf1af9616572fdb72e3a | 6,270 |
= = Los Alamos Laboratory = =
| 62af2c7dffee09b0677674ffb2f9be83 | 6,272 |
In 1944 Richard Feynman recruited Reines to work in the Theoretical Division at the Manhattan Project 's Los Alamos Laboratory , where he would remain for the next fifteen years . He joined Feynman 's T @-@ 4 ( Diffusion Problems ) Group , which was part of Hans Bethe 's T ( Theoretical ) Division . Diffusion was an important aspect of critical mass calculations . In June 1946 , he became a group leader , heading the T @-@ 1 ( Theory of Dragon ) Group . An outgrowth of the " tickling the Dragon 's tail " experiment , the Dragon was a machine that could attain a critical state for short bursts of time , which could be used as a research tool or power source .
| aab5e585226bf42809cb7680463511ff | 6,274 |
Reines participated in a number of nuclear tests , and writing reports on their results . These included Operation Crossroads at Bikini Atoll in 1946 , Operation Sandstone at Eniwetok Atoll in 1948 , and Operation Ranger and Operation Buster – Jangle at the Nevada Test Site . In 1951 he was the director of Operation Greenhouse series of nuclear tests in the Pacific . This saw the first American tests of boosted fission weapons , an important step towards thermonuclear weapons . He studied the effects of nuclear blasts , and co @-@ authored a paper with John von Neumann on Mach stem formation , an important aspect of an air blast wave .
| 3a56afe820d6ebcbf0ddb2d936588498 | 6,275 |
In spite or perhaps because of his role in these nuclear tests , Reines was concerned about the dangers of radioactive pollution from atmospheric nuclear tests , and became an advocate of underground nuclear testing . In the wake of the Sputnik crisis , he participated in John Archibald Wheeler 's Project 137 , which evolved into JASON . He was also a delegate at the Atoms for Peace Conference in Geneva in 1958 .
| 39b06da78d1617f5b635e18532ac6bf6 | 6,276 |
= = Discovery of the neutrino and the inner workings of stars = =
| 8b37f6cf76b7b2c9ecde627407e59aca | 6,278 |
The neutrino was a subatomic particle first proposed theoretically by Wolfgang Pauli on December 4 , 1930 , to explain undetected energy that escaped during beta decay when neutron decayed into a proton and an electron so that the law of conservation of energy was not violated . Enrico Fermi renamed it the neutrino , Italian for " little neutral one " , and in 1934 , proposed his theory of beta decay which explained that the electrons emitted from the nucleus were created by the decay of a neutron into a proton , an electron , and a neutrino :
| 6baa62024e0853f086b77f692ba44846 | 6,280 |
n0 → p + + e − + ν
| ae88b15a337cfdc4158ccef2188112bc | 6,281 |
e
| 16812eaedd5b4164694cc9e16c62278d | 6,282 |
The neutrino accounted for the missing energy , but Fermi 's theory described a particle with little mass and no electric charge that would be difficult to observe directly . In a 1934 paper , Rudolf Peierls and Hans Bethe calculated that neutrinos could easily pass through the Earth , and concluded " there is no practically possible way of observing the neutrino . " In 1951 , at the conclusion of the Greenhouse test series , Reines received permission from the head of T Division , J. Carson Mark , for a leave in residence to study fundamental physics . Reines and his colleague Clyde Cowan decided to see if they could detect neutrinos . " So why did we want to detect the free neutrino ? " he later explained , " Because everybody said , you couldn ’ t do it . "
| 7c06c930dfa7d1e7cf4bd13fd8ec1220 | 6,283 |
According to Fermi 's theory , there was also a corresponding reverse reaction , in which a neutrino combines with a proton to create a neutron and a positron :
| c46747c92b917f641fd773515c9b1c79 | 6,284 |
ν
| a24d7e40e00abe478105d39402a35919 | 6,285 |
e + p + → n0 + e +
| bc61fabf6226c21f84d6d93667c27ab1 | 6,286 |
The positron would soon be annihilated by an electron and produce two 0 @.@ 51 MeV gamma rays , while the neutron would be captured by a proton and release a 2 @.@ 2 MeV gamma ray . This would produce a distinctive signature that could be detected . They then realised that by adding cadmium salt to their liquid scintillator to enhance the neutron capture reaction , resulting in a 9 MeV burst of gamma rays . For a neutrino source , they proposed using an atomic bomb . Permission for this was obtained from the laboratory director , Norris Bradbury . Work began on digging a shaft for the experiment when J. M. B. Kellogg convinced them to use a nuclear reactor instead of a bomb . Although a less intense source of neutrinos , it had the advantage in allowing for multiple experiments to be carried out over a long period of time .
| 3524b9796cf25b6d355f893a3901af72 | 6,287 |
In 1953 , they made their first attempts using one of the large reactors at the Hanford nuclear site in what is now known as the Cowan – Reines neutrino experiment . Their detector now included 300 litres ( 66 imp gal ; 79 US gal ) of scintillating fluid and 90 photomultiplier tubes , but the effort was frustrated by background noise from cosmic rays . With encouragement from John A. Wheeler , they tried again in 1955 , this time using one of the newer , larger 700 MW reactors at the Savannah River Site that emitted a high neutrino flux of 1 @.@ 2 x 1012 / cm2 sec . They also had a convenient , well @-@ shielded location 11 metres ( 36 ft ) from the reactor and 12 metres ( 39 ft ) underground . On June 14 , 1956 , they were able to send Pauli a telegram announcing that the neutrino had been found . When Bethe was informed that he had been proven wrong , he said , " Well , you shouldn ’ t believe everything you read in the papers . "
| 6b22eed33aee669b97e3aec762be17f8 | 6,288 |
From then on Reines dedicated the major part of his career to the study of the neutrino ’ s properties and interactions , which work would influence study of the neutrino for future researchers to come . Cowan left Los Alamos in 1957 to teach at George Washington University , ending their collaboration . On the basis of his work in first detecting the neutrino , Reines became the head of the physics department of Case Western Reserve University from 1959 to 1966 . At Case , he led a group that was the first to detect neutrinos created in the atmosphere by cosmic rays . Reines had a booming voice , and had been a singer since childhood . During this time , besides performing his duties as a research supervisor and chairman of the physics department , Reines sang in the Cleveland Orchestra Chorus under the direction of Robert Shaw in performances with George Szell and the Cleveland Orchestra .
| 44d8e51c77b0921cf93bdf8a03b39c1c | 6,289 |
In 1966 , Reines took most of his neutrino research team with him when he left for the new University of California , Irvine ( UCI ) , becoming its first dean of physical sciences . At UCI , Reines extended the research interests of some of his graduate students into the development of medical radiation detectors , such as for measuring total radiation delivered to the whole human body in radiation therapy .
| ec998bf8c701fb597b338d16a8b3788a | 6,290 |
Reines had prepared for the possibility of measuring the distant events of a supernova explosion . Supernova explosions are rare , but Reines thought he might be lucky enough to see one in his lifetime , and be able to catch the neutrinos streaming from it in his specially @-@ designed detectors . During his wait for a supernova to explode , he put signs on some of his large neutrino detectors , calling them " Supernova Early Warning Systems " . In 1987 , neutrinos emitted from Supernova SN1987A were detected by the Irvine – Michigan – Brookhaven ( IMB ) Collaboration , which used an 8 @,@ 000 ton Cherenkov detector located in a salt mine near Cleveland . Normally , the detectors recorded only a few background events each day . The supernova registered 19 events in just ten seconds . This discovery is regarded as inaugurating the field of neutrino astronomy .
| 9b7577543c90f6f94adc266db63c6b99 | 6,291 |
In 1995 , Reines was honored , along with Martin L. Perl with the Nobel Prize in Physics for his work with Cowan in first detecting the neutrino . Unfortunately , Cowan had died in 1974 , and the Nobel Prize is not awarded posthumously . Reines also received many other awards , including the J. Robert Oppenheimer Memorial Prize in 1981 , the National Medal of Science in 1985 , the Bruno Rossi Prize in 1989 , the Michelson – Morley Award in 1990 , the Panofsky Prize in 1992 , and the Franklin Medal in 1992 . He was elected a member of the National Academy of Sciences in 1980 and a foreign member of the Russian Academy of Sciences in 1994 . He remained dean of physical sciences at UCI until 1974 , and became a professor emeritus in 1988 , but he continued teaching until 1991 , and remained on UCI 's faculty until his death .
| e2e05d8da59993471561b60af876fc6a | 6,292 |
= = Death = =
| 051e29d68f7ca4b2c88d5604a1c1fd5b | 6,294 |
Reines died after a long illness at the University of California , Irvine Medical Center in Orange , California , on August 26 , 1998 . He was survived by his wife and children . His papers are in the UCI Libraries . Reines Hall at UCI was named in his honor .
| fd983932f3fb93fa574c34606ea90031 | 6,296 |
= = Publications = =
| 8dd81103a49b2ce73def56bd4e290f5e | 6,298 |
Reines , F. & C. L. Cowan , Jr . " On the Detection of the Free Neutrino " , Los Alamos National Laboratory ( LANL ) ( through predecessor agency Los Alamos Scientific Laboratory ) , United States Department of Energy ( through predecessor agency the Atomic Energy Commission ) , ( August 6 , 1953 ) .
| f5897254268a91b6336893e969e36f8e | 6,300 |
Reines , F. , Cowan , C. L. Jr . , Carter , R. E. , Wagner , J. J. & M. E. Wyman . " The Free Antineutrino Absorption Cross Section . Part I. Measurement of the Free Antineutrino Absorption Cross Section . Part II . Expected Cross Section from Measurements of Fission Fragment Electron Spectrum " , Los Alamos National Laboratory ( LANL ) ( through predecessor agency Los Alamos Scientific Laboratory ) , United States Department of Energy ( through predecessor agency the Atomic Energy Commission ) , ( June 1958 ) .
| 3ebb5b0c71f0f3f30d9657ac1d80c53b | 6,301 |
Reines , F. , Gurr , H. S. , Jenkins , T. L. & J. H. Munsee . " Neutrino Experiments at Reactors " , University of California @-@ Irvine , Case Western Reserve University , United States Department of Energy ( through predecessor agency the Atomic Energy Commission ) , ( September 9 , 1968 ) .
| 7b171db2b33c179e26cc0a3ecf5a68ab | 6,302 |
Roberts , A. , Blood , H. , Learned , J. & F. Reines . " Status and Aims of the DUMAND Neutrino Project : the Ocean as a Neutrino Detector " , Fermi National Accelerator Laboratory ( FNAL ) , United States Department of Energy ( through predecessor agency the Energy Research and Development Administration ) , ( July 1976 ) .
| 0ffab35257bf30409b59afea50e0f39c | 6,303 |
Reines , F. ( 1991 ) . Neutrinos and Other Matters : Selected Works of Frederick Reines . Teaneck , N.J. : World Scientific . ISBN 978 @-@ 981 @-@ 02 @-@ 0392 @-@ 4 .
| d41dde233d14e4319535c845fa4ba1d3 | 6,304 |
= Lock Haven , Pennsylvania =
| 3b8b0bfc5c68037599b5284cbbca7a84 | 6,307 |
The city of Lock Haven is the county seat of Clinton County , in the U.S. state of Pennsylvania . Located near the confluence of the West Branch Susquehanna River and Bald Eagle Creek , it is the principal city of the Lock Haven Micropolitan Statistical Area , itself part of the Williamsport – Lock Haven combined statistical area . At the 2010 census , Lock Haven 's population was 9 @,@ 772 .
| 5acbcfaf9c326327506ea3521f0736ed | 6,309 |
Built on a site long favored by pre @-@ Columbian peoples , Lock Haven began in 1833 as a timber town and a haven for loggers , boatmen , and other travelers on the river or the West Branch Canal . Resource extraction and efficient transportation financed much of the city 's growth through the end of the 19th century . In the 20th century , a light @-@ aircraft factory , a college , and a paper mill , along with many smaller enterprises , drove the economy . Frequent floods , especially in 1972 , damaged local industry and led to a high rate of unemployment in the 1980s .
| 5814421da2b5f88244d91b77c0508239 | 6,310 |
The city has three sites on the National Register of Historic Places — Memorial Park Site , a significant pre @-@ Columbian archaeological find ; Heisey House , a Victorian @-@ era museum ; and Water Street District , an area with a mix of 19th- and 20th @-@ century architecture . A levee , completed in 1995 , protects the city from further flooding . While industry remains important to the city , about a third of Lock Haven 's workforce is employed in education , health care , or social services .
| e46a1469dc7dc31dda11a605726e59f8 | 6,311 |
= = History = =
| fd3fc667e330e6e3944a4f085f9ef39d | 6,313 |
= = = Pre @-@ European = = =
| 5d4c95d30edea30529c1a864591e1c94 | 6,316 |
The earliest settlers in Pennsylvania arrived from Asia between 12000 BCE and 8000 BCE , when the glaciers of the Pleistocene Ice Age were receding . Fluted point spearheads from this era , known as the Paleo @-@ Indian Period , have been found in most parts of the state . Archeological discoveries at the Memorial Park Site 36Cn164 near the confluence of the West Branch Susquehanna River and Bald Eagle Creek collectively span about 8 @,@ 000 years and represent every major prehistoric period from the Middle Archaic to the Late Woodland period . Prehistoric cultural periods over that span included the Middle Archaic starting at 6500 BCE ; the Late Archaic starting at 3000 BCE ; the Early Woodland starting at 1000 BCE ; the Middle Woodland starting at 0 CE ; and the Late Woodland starting at 900 CE . First contact with Europeans occurred in Pennsylvania between 1500 and 1600 CE .
| d86671cee73575895db23cd8ba6cecaa | 6,318 |
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