Rings are more than just a piece of jewelry; they are heirlooms, symbols of love, and reminders of the milestones of our lives. From engagement rings to astrological signets, there are many different types of rings that have been used throughout history. But what is the science behind these enduring symbols?
A ring is an algebraic structure that generalizes fields: unlike the integers, which are a field under addition and multiplication, all numbers such as rational numbers, real numbers and complex numbers are rings (and therefore fields). Other examples of rings include cyclic groups Z nmathbbZ_n_(n_2) under their mod-n operations inherited from the integers; polynomial rings, which are of interest in algebraic geometry; and more abstractly, monoids internal to abelian groups, which are of interest in stable homotopy theory.
The concept of a ring dates back to the 1870s, with key contributions by Dedekind, Hilbert, and Fraenkel. Rings are important in number theory, as a way of generalizing the integers and the polynomials; they also play an essential role in algebraic geometry and invariant theory.
While the word ring derives from an ancient Hebrew word, Tabbaath, meaning “sink,” it was not always a sign of marriage or loyalty; it could also be used as a seal on contracts and legal documents. The Old Testament mentions a ring that Pharaoh gave Joseph, for example, to seal his authority (Genesis 41:42), as well as a ring that Ahasuerus gave Haman, to sign the royal missive (Esther 3:12).
In modern astronomy, rings are patterns of light in the Solar System that appear around planets and other bodies. These rings are created when reflected and refracted light bounces off the body’s surface. Astronomers use these rings to understand the dynamics of our Solar System, including how moons and planets form, and even the nature of dark matter.
A ring is not a permanent size; it will shrink or swell in response to a number of factors. For example, it’s common for women to experience a ring that feels tight during pregnancy; the rings in their fingers are enlarged by an increase in blood flow and the pressure on them from the baby. Other factors that affect ring sizes include cold weather and swimming; the temperature change can cause your fingers to shrink, which will also make a ring feel looser. Similarly, a ring may be too large or too small because you have gained or lost weight. If your ring is too small or too big, you can get it resized by an expert. This will ensure that the ring fits correctly and is not damaging the knuckle, or the finger itself.