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Maria Cunitz  
  
1197   02:50 صباحاً   date: 24-1-2016
Author : R A Hatch
Book or Source : The Cunitz Page : A Brief Chronology of the Life of Maria Cunitz
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Date: 25-1-2016 1740
Date: 19-1-2016 1190
Date: 24-1-2016 1480

 

Born: about 1607 in Schweidnitz, Silesia (now Świdnica, Poland)
Died: 22 August 1664 in Pitschen, Duchy of Brieg, Silesia (now Byczyna, Poland)


Maria Cunitz's parents were Maria Schultz and Henrich Cunitz and Maria was their eldest daughter. The date we have given for Maria's birth is unfortunately not known precisely. We do know that she must have been born after 1604 and we know that she certainly was born before 1610. It is hoped that furtherresearch will enable the precise date to be found but, failing this, we have split the difference so as to minimise the possible error. The place of her birth is believed to be Schweidnitz as her father Henrich Cunitz was a medical doctor in Schweidnitz (Swidnica in Polish). Certainly she was brought up in this town on the river Bystrzyca, a tributary of the river Oder. The town of Schweidnitz (or Swidnica) is today in south west Poland.

At this time there was no possibility of any advanced education for a woman but Cunitz was lucky because her father acted as her teacher. It is a little difficult now to assess exactly how far her education took her, but Johann Kaspar Eberti, writing in Educated Silesian Women and Female Poets in 1727 long after her death, claimed that Cunitz mastered many languages, in particular Hebrew, Greek, Latin, German, Polish, Italian, and French. She was also skilled in painting, music and poetry. This was an exceptional achievement, but all these subjects would have been considered suitable for a woman. Much more remarkably, she also learnt mathematics, medicine, and history which were certainly considered subjects unsuitable for a woman at this time. Certainly she learnt these latter topics from Elias von Löwen, a medical doctor in Pitschen who also had an amateur interest in astronomy. There are records of observations of Venus made by Cunitz and von Löwen in December 1627 and of Jupiter in April 1628.

In 1630 Cunitz married Elias von Löwen. He continued to encourage his wife's interest in astronomy and Maria needed little encouragement to throw herself into this topic with enthusiasm. However, she had little chance to excel as an observational astronomer through lack of good quality instruments, so to make a worthwhile contribution she had to apply her mathematical skills to astronomy. But this was a time of conflict and, from 1634 onwards, fighting in central Europe caused many to flee. Armies not only caused damage by fighting each other but also plundered towns and farms on their route for food and other supplies. Cunitz and her husband fled to avoid the destruction and took refuge in the village of Lubnice, in the estate of the Cistercian convent of Olobok, in the south of Kalisz. It was here that Cunitz began the mathematical work which led to her publishing Urania propitia, sive Tabulae Astronomicae mirè faciles in 1650. In 1648 the couple were able to return to their home in Pitschen and Cunitz resumed correspondence which other leading astronomers and mathematicians as well as concentrating on her work on the tables. She examined Kepler's Rudolphine Tables (1628) which were based on Tycho Brahe's observations and Kepler's first two laws. Cunitz found errors in the Kepler tables and also found that his use of logarithms made his tables difficult to use.

The Urania propitia certainly has the merit of being simpler to use than Kepler's tables and Cunitz was able to correct a number of errors in the Rudolphine Tables. However, due to neglecting small terms in the formulas that she used, Cunitz introduced some new errors into the tables. The book of tables was dedicated to Emperor Ferdinand III and contained a Preface by Cunitz's husband Elias von Löwen in which he acknowledged that the work was not due to him but to his wife. Cunitz's introduction which follows was written in both Latin and German. The book was not widely read so relatively few copies have survived. However, recently the University of Florida purchased one of the nine copies known to still survive:-

The book that has been chosen as the four-millionth volume for the University of Florida Libraries is 'Urania Propitia' by Maria Cunitz. The book examines the theory and art of astronomy, as well as presents her calculations, and a guide to astronomy for nonscientists. According to Cunitz, there were four components to astronomy: carefully recorded observations, the construction of astronomical instruments, theory, and the calculations or tables of predictions. The book is very rare - one of nine copies in existence - and is an important addition to the libraries because it celebrates the university's commitments to women's studies, history of science, astronomy, and the printed word as the prime means of communication for more than five hundred years.

We mentioned above that Cunitz corresponded with other leading astronomers and mathematicians. Of course conventions of the time made this somewhat difficult and so largely the correspondence would be addressed to her husband. Perhaps, therefore, it would be more accurate to say that Cunitz and her husband corresponded with astronomers. In January 1650 they began a correspondence with Johannes Hevelius from Gdansk who had produced Selenographia in 1647, one of the first detailed maps of the moon's surface. Hevelius suggested that Cunitz correspond with Ismael Boulliau who was a librarian working with the brothers Pierre and Jacques Dupuy at the Bibliothèque du Roi in Paris. He had published Astronomia philolaica in 1645, a work which accepted elliptical orbits for planets and claimed that if a planetary moving force existed then it should vary inversely as the square of the distance. It is not surprising that Boulliau considered that his tables gave more accurate data for the position of Mercury, Jupiter, Saturn, and the Moon than did Cunitz's tables.

On 25 May 1656 a major fire destroyed many of the houses in Pitschen. The home of Elias von Löwen and his wife was almost completely destroyed, as was Maria's books, papers, letters and equipment. Records of observations made over many years were lost that evening in the fire. Cunitz's husband died in 1661 and she only outlived him by three years.

We have mentioned above the 1727 book Educated Silesian Women and Female Poets by Johan Kaspar Elberti in which he gives details of Cunitz's life. Elberti makes a critical remark which illustrates nicely the difficulties that women scholars of the time had to overcome:-

[Cunitz] was so deeply engaged in astronomical speculation that she neglected her household. The daylight hours she spent, for the most part, in bed (concerning which all manner of ridiculous events have been reported) because she had tired herself from watching the stars at night.


 

Books:

  1. M Alic, Hypatia's Heritage : A history of women in science from antiquity to the late nineteenth century (The Women's Press, London, 1986).
  2. R A Hatch, The Cunitz Page : A Brief Chronology of the Life of Maria Cunitz (University of Florida).

 

 

 




الجبر أحد الفروع الرئيسية في الرياضيات، حيث إن التمكن من الرياضيات يعتمد على الفهم السليم للجبر. ويستخدم المهندسون والعلماء الجبر يومياً، وتعول المشاريع التجارية والصناعية على الجبر لحل الكثير من المعضلات التي تتعرض لها. ونظراً لأهمية الجبر في الحياة العصرية فإنه يدرّس في المدارس والجامعات في جميع أنحاء العالم. ويُعجب الكثير من الدارسين للجبر بقدرته وفائدته الكبيرتين، إذ باستخدام الجبر يمكن للمرء أن يحل كثيرًا من المسائل التي يتعذر حلها باستخدام الحساب فقط.وجاء اسمه من كتاب عالم الرياضيات والفلك والرحالة محمد بن موسى الخورازمي.


يعتبر علم المثلثات Trigonometry علماً عربياً ، فرياضيو العرب فضلوا علم المثلثات عن علم الفلك كأنهما علمين متداخلين ، ونظموه تنظيماً فيه لكثير من الدقة ، وقد كان اليونان يستعملون وتر CORDE ضعف القوسي قياس الزوايا ، فاستعاض رياضيو العرب عن الوتر بالجيب SINUS فأنت هذه الاستعاضة إلى تسهيل كثير من الاعمال الرياضية.

تعتبر المعادلات التفاضلية خير وسيلة لوصف معظم المـسائل الهندسـية والرياضـية والعلمية على حد سواء، إذ يتضح ذلك جليا في وصف عمليات انتقال الحرارة، جريان الموائـع، الحركة الموجية، الدوائر الإلكترونية فضلاً عن استخدامها في مسائل الهياكل الإنشائية والوصف الرياضي للتفاعلات الكيميائية.
ففي في الرياضيات, يطلق اسم المعادلات التفاضلية على المعادلات التي تحوي مشتقات و تفاضلات لبعض الدوال الرياضية و تظهر فيها بشكل متغيرات المعادلة . و يكون الهدف من حل هذه المعادلات هو إيجاد هذه الدوال الرياضية التي تحقق مشتقات هذه المعادلات.