English
Related papers

Related papers: A geometrical link between the circle and sexagesi…

200 papers

A new idea for a binary clock is presented. It displays the time using a triangular array of 15 bits. It is shown that such a geometric, triangular arrangement is only possible because our system of time divisions is based on a sexagesimal…

History and Overview · Mathematics 2010-06-09 Joerg Pretz

In a recent article by Scafetta, 2010, the author investigates whether or not the decadal and multi-decadal climate oscillations have an astronomical origin. In particular, the author note that several global surface temperature records,…

Data Analysis, Statistics and Probability · Physics 2011-05-20 S. Sello

This article is inspired by the great conjunction of Jupiter and Saturn on December 21st, 2020. We will address the following questions from a mathematical standpoint. What is a conjunction? How often do we have a conjunction of two…

History and Overview · Mathematics 2022-03-25 Sunil K. Chebolu

This study reconstructs the origin of a constant, here called $\Xi$ (Xi), as a primary scaling factor in Old Babylonian mathematics and astronomy. $\Xi$ arises from the practical necessity of precise measurements on the sky or a circle,…

History and Overview · Mathematics 2026-04-10 Jens Kleb

A surprisingly large amount of information on our solar system can be gained from simple measurements of the apparent angular diameters of the sun and the moon. This information includes the average density of the sun, the distance between…

Physics Education · Physics 2009-11-10 K. Capelle

It has been established that the Rieger periodicity of approximately 153 days is part of a complex of periodicities, all multiples of a basic period of approximately 25.5 days. However, it has not been clear why the sixth subharmonic of…

Astrophysics · Physics 2007-05-23 P. A. Sturrock

Earth's analemma is the lopsided figure eight marked out over a year by the position of the Sun in the sky observed at the same clock time each day. It shows how solar time deviates from clock time. The analemma's shape results from the…

Popular Physics · Physics 2013-02-05 Charles H. Holbrow

Ptolemy's model of the Moon's motion implied that its distance varies by nearly a factor of two, implying that its angular size should also vary by nearly a factor of two. We present an analysis of 100 naked eye observations of the Moon's…

History and Philosophy of Physics · Physics 2013-11-13 Kevin Krisciunas

This article discusses the reasons for the choice of the sexagesimal system by ancient Sumerians. It is shown that Sumerians chose this specific numeral system based on logical and practical reasons which enabled them to deal with big…

History and Overview · Mathematics 2023-06-12 Kazuo Muroi

We have proposed a model to obtain the length of the day and month at any geologic time. The day is found to increase by 0.002 sec/century since the seventeenth century. The lengthening of the day is attributed entirely to the increasing…

General Physics · Physics 2007-05-23 A. I. Arbab

The Six Circles Theorem of C. Evelyn, G. Money-Coutts, and J. Tyrrell concerns chains of circles inscribed into a triangle: the first circle is inscribed in the first angle, the second circle is inscribed in the second angle and tangent to…

Metric Geometry · Mathematics 2014-03-11 Dennis Ivanov , Serge Tabachnikov

The way galaxies assemble their mass to form the well-defined Hubble sequence is amongst the most debated topic in modern cosmology. One difficulty is to link distant galaxies to those at present epoch. We aim at establishing how were the…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-13 R. Delgado-Serrano , F. Hammer , Y. B. Yang , M. Puech , H. Flores , M. Rodrigues

The purpose of this note is to report, in narrative rather than rigorous style, about the nice geometry of $6$-division points on the Fermat cubic $F$ and various conics naturally attached to them. Most facts presented here were derived by…

Algebraic Geometry · Mathematics 2022-11-02 Tomasz Szemberg , Justyna Szpond

Second part of a didactic sequence of activities on some topics of Astronomy, related mainly with the real shape of the Earth, the gravitational interactions between our planet and other celestial bodies, and the resulting movement of the…

Popular Physics · Physics 2011-08-01 Alejandro Gangui

In the paper, elements of the system theory of time are presented, mathematical models for time are constructed, and various properties are deduced from the main principles of the system theory of time. This theory is a far-reaching…

General Physics · Physics 2007-05-23 Mark Burgin

The physical origin of the leap second is discussed in terms of the new gravity model. The calculated time shift of the earth rotation around the sun for one year amounts to $\displaystyle{\Delta T \simeq 0.621 s/ year}$. According to the…

General Physics · Physics 2009-11-12 Takehisa Fujita , Naohiro Kanda

We treat, as an illustrative example of gravitational time dilation in relativity, the observation that the center of the Earth is younger than the surface by an appreciable amount. Richard Feynman first made this insightful point and…

Physics Education · Physics 2016-04-20 Ulrik I. Uggerhoj , Rune E. Mikkelsen , Jan Faye

The observation that the shadows of objects change during the course of the day and also for a fixed time during a year led curious minds to realize that the Sun could be used as a timekeeper. However, the daily motion of the Sun has some…

Physics Education · Physics 2018-12-31 Alejandro Gangui , Cecilia Lastra , Fernando Karaseur

We present an analytical proof assisted by computer calculations for the dynamical stability of the eight main planets and Pluto for the next 100,000 years. It means that the semi-major axes of the planets will not change significantly…

Earth and Planetary Astrophysics · Physics 2022-06-28 Angel Zhivkov , Ivaylo Tounchev

If P is a point inside triangle ABC, then the cevians through P divide triangle ABC into six smaller triangles. We give theorems about the relationship between the radii of the circles inscribed in these triangles.

History and Overview · Mathematics 2019-09-04 Stanley Rabinowitz
‹ Prev 1 2 3 10 Next ›