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????? ????????? ?? ?????? ???????? (Back of The Envelope). ?????? ??? ?????? ??????? ??? ????? ???? ????? ?????? ?? ??????? ??????? ???? ????? ????? ?? ?????? ?????? ??? ?????? ????? ??? ?? ?????? ??? ????? ??? ?? ?????? ????? ????? ????? ?? ????? ?????. ???????? ?? ?????? ???????? ?????? ?? ???? ????? ???? ?? ???? ????? ?????? ?? ?????? ?? ???? ?????? ???? ????? ??? ??????? ?? ?? ???? ?? ???? ?????? ????? ???????.

?????? ???? ???????? ??? ????? ??? ???? ??? ??????? ???????? ??? ????? ??? ????? ?????? ????? ???????? ???????? ??????? ??????????? ?????? ?? ??? ??????? ??? ????? ????????? ??????? ???? ??????. ??? ??? ?????? ?????? ???????? ??? ???? ??? ??? ????? ????? ????????? ?????? ???? ?? ????? ???? ?????? ?????????. ??????? ??? ???? ?? ??????? ???????  (Abraham Lincoln)??? ??? ?????? ??????? ???????? ??? ??? ??????? ??? ???? ?????? ?? ?????????? (Pennsylvania) ??? ???? ??????? ???? ????? ?????. ????? ?????? ???? ??? ??? ???? ???? ?????? ??? ??? ??? ???? ??? ??? ??? ??????? “??? ??? ????”. ???? ??? ??????? ??? ?????? ??? 272 ???? ???.

??? ??? ??????? ?????? ?? ??????? ???????? ?????? ?????? ???????? ?????? ??????? ???????? ???? ????? ???? ???? ????? ?? ??????? ?? ????? ???????? ?????. ???? ??? ??????? ?? ??????? ??????? ??????? ??????? ??????? ??????? ???? ???? ???? ???? ?? ??? ??????? ???????? ???? ?? ????? ???????? ?? ???? ??????? ??????? ???? ???? ????? ?????? ???????? ?? ???? ???? ???? ?? ?????? ?????? ???????? ??? ???????? ????????? ????? ?? ???? ???? ?? ?? ??? ????. ??????? ??? ???? ????? ??????? ????????? ??????? ?? ?????? ????????? ???? ????? ????? ?? ????? ???? ???? ??????? ????????? ??????? “??? ???? ???????”. ??????? ????? ????? “??? ???????” ?? ?? ??? ??????? ?? ???? ??????? ???? ??????? ??????? ???? ???????? ?? ????? ????????.

???? ???? Back of the Envelope, by Frank Jankowski (Pittsburgh: Dor­rance, 1999) ????? ?????? ???? ??????? ??????????? ?? ????????? ????????? ??? ????? ?????? ???? ????????? (Jankowski) ??? ?????? ???????? ???? ???? ?? ????? ???????? ?????? ????? ?? ??? ???? ?? ???????? ?? ??? ??? ?????? ??????? ?????? ???????? ??????? ?????? ???? ??????:

?? ????? ??? ?????? (Back-of-the-Envelope) ???? ???? ??? ????? ???????? ??? ??? ????? ???????. ??????? ?? ????? ??????? ??????? ?? ????? ????? ??????? ?????? ???? ????? ?????? ???? ??? ???? ??? ??????? ???????? ????? ????? ???? ????? ???? ??????? ?? ??????? ????????. ???? ???????? ???? ?? ?????? ?????? ??? ?? ?? ???? ???? ?? ??? ?? ????? ????? ????????.

???? ????????? ????? ?? ??????? ???????? ????????? (?????? ??? ??????) ??? ???? ??? ????? ??? ????? (Jon Bentley) ?? ??????(“The Back of the Envelope”, which Appeared Originally in his column “Programming Pearls,” in the: Com­munications of the Association for Computing Machinery. The Essay is Reprinted in Bentley’s Book Programming Pearls (Readings, Mass.: Addison-Wesley, 1986)) .

??? ??? ?????? ?????? ??? ???? ????? ?????? ?????? ??????? ?????? ?? ?????? ??? ??? ??????? (Back-of-the-Envelope):

??? ?? ???? ??? (Maine)? ??? ?????? ????? ?????? ??? ?????? ??? ????? ?????? ???? ???? (Homer Potter). ???? ???? ??? ?? ??????? ?? ???????? (Connecticut) ????? ??????? 200 ??? ?? ??????? ??????. ???? ????? ??? ??: ????. ?? ??? ?????? ??? ?????? ????? ?????? ?? 15 ?????? ???? ??????? ?? ?? ?????? ??? ???? ???????? ?????? ?????? ??????? ??? ?????? 12 ???????? ?? ???? ?? 100 ?????? ?? ???. ?? ??? ?? ??? ??????!

“???? ?? ????? ????” ??? ???? ??????. ????? “??? ?? ????? ?? ???!”

?? ??? ???? ?? ????? ???? ???? ?? ???. ???? ??????? ??? ????: “????? ?????? ??? ????????? ????? ??????? 20 ????? ?? ?????.

??? ????? ??????? ????????? ?? ????? “??? ?????? ??????!”.

??? ??????? ??????? ???? ?????? ????? ?????? ?????? ?????? ???? ????? ???? ??? ??????? ????????? ?? ??????? ????????? ??????? (Summer Olympic Games) ???? 1984. ?????? ???? ??? ??????? ???? ???? ??????? ????? ?????? ???????? ???? ???? ?????? ????? ?? ?????? ??????? ???? ??????? ??? ??? ?? ?? ????? ?? 120 ?????! ????? ???? ??????? ?????? ??? ?????? ????? ?????? ?? ???????? ???? ???????? ?????????? ????? ?????? ?? ????? ?????.

???? ??????? ?? ????? ?? ?????? ??? ??? ????????. ??????? ???? ??????? ??? ?? ??? ???? ?? ???? ???? ????? ??? ????? ??? ?????? ?????? ??????? ??????? ?? ????? ???????? ??? ???????? ???? ????? ?????? ??? ???? ?????? ??????? ????? ????????? (Mario Salvadori) (1907-1997)? ???? ??? ?????? ????? ??????????? ???? ????? ??? “??? ??????? ???????? ?? ?? ????? ?????? ????? ???????”:

????? ??????? ????????? ???????? ???? ???????? ????????? ????? ???? ?????? ???? ?? ???? ????? ?????? ??????? ?? ???????? ???? ????? ????? ???? ?????? ?? ?????. ???? ??? ??????? ?? ??? ????? ?????? 7 ?????? ?????? ???? ?????? ?????? ???????? (??? ??? ????) ?????? ????? ???? ???? ?? ?????? ????? ?????? ?????? ???????. ??? ??? ???? ????? ???? ?????? ?????? ???? ????? ??????? ?????.

????? ???? ????????? ?????? ??????? ????? ???????? ????? ???? ?? ?????? ??? ????????. ???????? ??????? ??? “???? ?????”? ??? ???? ???? ?? ???? ??????? ???? ???? ?? ????????? ?????.

??? ?? ???? ?????? ?? ????????? ????????? ??? ???? ???????? ????????? (??? ??? ???????) ?????? ??????? ??? ????????? ???? ??? ????? ????? ??? ????? ????????????? ?? ???? ??????? “??? ??? ???????” ??? ??? “?????? ?????” (Fermi Calculations) ????????? ???????. ?????? ?? ?? ?????? ????? (Enrico Fermi) ?????? ????????? (Robert Oppenheimer) ????? ???? ????? ??????? (Manhattan) ????? ???? ???? ???? ?????? ??????? ??????? ??? ???? ???? ??? ??? ???? ????? ?? ????????. ??? ????? ????? ????? ?? ????? ??? ??? ????? ?????? ?????? ?? ?????? ????? ??? ??????. ???? ?????? ???? ??????? ???? ??????? ???? ?????? ??? ?????? ?? ??? ??????? ??????? (??? ??? ???????) ????? ???? ??? ??? ???? ??? ??????? ?????????? ???????? ???? ????? ??? ??? ???? ???? ???????? ????? ?????? ????? ?????.

?? ??? ??? ??? ??? ????? ?? ?? ????? ??? ?? ?????? ??? ??? ?? ???? ?? ???? ???????? ?? ?????? ???????? ????????? ???? ?????? ???? ?? ??? ?? ???? ????? ??? ??? ??? ????? ??? ???????? ?? ??? ???? ???? ????? ?????? ??? ????? ?? ?????? ?????? ?????? ????? ?? ????? ?????? ?? ????? ???? ???????? ?????. ????:(Clifford Swartz, Back-of-the-Envelope Physics (Baltimore: Johns Hopkins University Press, 2003).

?????? ?? ??????? ?? ????? ??? ????? ???? ???????? ??? ??????? ?? ??? ???? ?? ?????? ????? ??? ??? ?????? (John Stevens) (1715-1792)? ??????? ???????? ???? ???? ????? ?????? ????? ?????? ??????? ???? ??? ????? ?? ????????? ???????. ????? ???? ????????:

???? ????? ????? ??????? ?? ???? ??? ????? ????? ???? ?????? ????? ??????????? ???? ??? ?? ??? ???? ??? ????? ?????? ??? ???? ???? ????? ??? ?????? ????? ???? ?????? ??? ??? ????? ??? ???????? ????? ???? ??????? ??? ?????? ??????. “?? ?????? ?? ??? ???? ?????”? ????? ????? ???? ?? ?????????.

?????: “??? ?? ??? ??????? ??? ??? ??? ????”.

???? ??? ????????? ??? ????? ??? ???? ??? ?????? ??? ???? ?? ??? ????????. ???? ??????? ????? ??? ??????? ??? ????? ??????? ????? ?????? ???? ?????? (James E. Gordon) (1913-1998) ?? ????? ??????:Structures: Or Why Things Don’t Fall Down (New York: Da Capo, 1978).

?? ????? ??????? ?????? ????? ???? ????? ???? ??????? ?? ??? ????????? ?? ???? ????????? ???????? ????????? ???? ??????? ???? ??? ?? ???? ??? ????? ?? ??????? ??????? ?? ????? ??????. ???? ?? ??? ?? ??? ????? ?? ????? ????? ?? ???? ???? ??? ??????? ??? ?? ???? ???? ??? ?? ???? ???? ?? ???? ????? ??????? ??? ??? “?????” ?????? ???? ?????? ?? ???? ??????? ?? ????? ???? ???? ??? ??? ?????. 

???? ???? ?????? “On the Backs of Envelopes,” American Scien­tist, January-February 1991, pp. 15-17, which is Reprinted in: Remaking the World (New York: Knopf, 1997). ???? ?????? ???? ??? ??? ???????? [??? ??????? ??? ??? ??????].

?????? ????????? ????? ?? “???? ???????” (Envelope of Experience)? ???? ??????? ???????? ??? ????? ????? ??????? – “????” ?????? ???????? ?????? ????? – ???? ????? ????? ??????. ??????? ??? “?? ??? ??????” ?? “??? ??????” ???? ????? ??????? ?????? ?????? ??????? ??????? ????? ???? ??? ????? ??????? ?????????.

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