How does math guide our ships at sea? - George Christoph

Cum rezolvă matematica navigaţia pe mare?

Transcriber: tom carter Reviewer: Bedirhan Cinar

Traducător: Doina Zamfirescu Corector: Ariana Bleau Lugo

As you can imagine, 400 years ago,

Va imaginaţi că acum 400 de ani

navigating the open ocean was difficult.

a naviga pe ocean era foarte dificil.

The winds and currents pushed and pulled ships off course,

Vântul şi curenţii împiedicau vasele să-şi urmeze cursul,

and so sailors based their directions on the port they left,

iar marinarii stabileau direcţia faţă de portul de plecare,

attempting to maintain an accurate record of the ship's direction and the distance sailed.

încercând să monitorizeze corect direcția şi distanţa de parcurs.

This process was known as dead reckoning,

Procesul era cunoscut ca drum estimat,

because being just half a degree off could result in sailing right past the island that lay several miles just over the horizon.

pentru că o deviaţie de 1 grad însemna ratarea destinaţia.

This was an easy mistake to make.

Se putea întâmpla foarte uşor.

Thankfully, three inventions made modern navigation possible:

Însă trei invenţii au făcut posibilă navigarea modernă:

sextants, clocks and the mathematics necessary to perform the required calculations quickly and easily.

sextanţii, ceasurile şi matematica pentru calculele corecte şi rapide.

All are important. Without the right tools, many sailors would be reluctant to sail too far from the sight of land.

Toate importante. Fără acestea marinarii nu puteau naviga prea departe.

John Bird, an instrument maker in London,

John Bird, un meşter din Londra,

made the first device that could measure the angle between the sun and the horizon during the day,

a creat primul dispozitiv care măsura unghiul dintre soare şi orizont,

called a sextant.

numit sextant.

Knowing this angle was important, because it could be compared to the angle back in England at the exact same time.

Unghiul era important pentru a fi comparat cu cel din Anglia, simultan.

Comparing these two angles was necessary to determine the longitude of the ship.

Compararea unghiurilor determina longitudinea vasului.

Clocks came next.

Apoi au venit ceasurile.

In 1761, John Harrison, an English clockmaker and carpenter,

În 1761, John Harrison, ceasornicar şi tâmplar,

built a clock that could keep accurate time at sea.

a construit un ceas care arăta timpul precis parcurs pe mare.

The timepiece that could maintain accurate time while on a pitching, yawing deck in harsh conditions

Menținea timpul corect și în condiţii dificile

was necessary in order to know the time back in England.

pentru a fi calculată durata întoarcerii în Anglia.

There was one catch though:

Avea însă un dezavantaj:

since such a timepiece was handmade, it was very expensive.

fiind făcut manual, era foarte scump.

So an alternate method using lunar measurements and intense calculations was often used to cut costs.

Aşa că se foloseau complexe măsurători şi calcule selenare.

The calculations to determine a ship's location for each measurement could take hours.

Dar aceste măsurători puteau dura ore.

But sextants and clocks weren't useful unless sailors could use these tools to determine their position.

Iar instrumentele erau utile dacă marinarii ştiau să le folosească.

Fortunately, in the 1600s, an amateur mathematician had invented the missing piece.

În 1600, un matematician amator a inventat piesa lipsă.

John Napier toiled for more than 20 years in his castle in Scotland to develop logarithms, a calculation device.

John Napier s-a străduit 20 de ani, în castelul său din Scoţia, să inventeze logaritmii.

Napier's ideas on logarithms involved the form of one over E and the constant 10 to the seventh power.

Logaritmii lui Napier foloseau 1/ e şi constanta 10^7.

Algebra in the early 1600s was not fully developed,

În 1600 algebra nu era pe deplin dezvoltată,

and Napier's logarithm of one did not equal zero.

iar logaritmul lui Napier nu se reducea la zero.

This made the calculations much less convenient than logarithms with a base of 10.

Aceste calculele erau mult mai grele decât logaritmii în bază 10.

Henry Briggs, a famous mathematician at Gresham College in London,

Henry Briggs, un faimos matematician de la Colegiul Gersham, Londra,

read Napier's work in 1614, and the following year made the long journey to Edinburgh to meet Napier.

a citit lucrarea lui Napier în 1614 şi în anul următor a făcut o călătorie lungă să-l întâlnească.

Briggs showed up unannounced at Napier's castle door

Briggs a apărut neanunţat la castelul lui Napier

and suggested that John switch the base and form of his logarithms into something much simpler.

şi i-a sugerat să simplifice forma și baza logaritmilor.

They both agreed that a base of 10 with the log of one equal to zero

Ambii au fost de acord că în baza 10, log (1)=0

would greatly simplify everyday calculations.

ar simplifica mult calculele.

Today we remember these as Briggs Common Logarithms.

Azi îi cunoaştem ca Logaritmii lui Briggs.

Until the development of electric calculating machines in the 20th century,

Pănă la maşinile electrice de calcul din sec. XX,

any calculations involving multiplication, division, powers, and extraction of roots with large and small numbers

înmulțirea, împărțirea, puterile şi extragerile de radical din numere foarte mari sau foatre mici

were done using logarithms.

erau făcute prin logaritmi.

The history of logarithms isn't just a lesson in math.

Istoria logaritmilor nu e doar o lecţie în matematică.

There were many players responsible for successful navigation.

Mulţi au contribuit la succesul navigaţiei.

Instrument makers, astronomers, mathematicians,

Astronomi, matematicieni, meşteşugari,

and of course sailors.

şi desigur marinari.

Creativity isn't only about going deep into one's field of work,

Creativitatea nu înseamnă doar aprofundarea unui domeniu de cercetare,

it's about cross-pollination between disciplines too.

ci şi colaborarea dintre domenii diferite.