What is the Glashow's snake?



Instructions & questions:

Describe the picture above. 
What "Weak" & "Strong" refer to? And what about "E & M"?
Have you ever heard about Dark Matter? Could you explain what is it?
If you think of what you have learnt about stellar nucleosynthesis, can you comment upon the relation between some astronomical scale and the subatomic scale?
Who is Sheldon Glashow?
Do you know what G.U.T stands for? What would be the French word for it?
Find out more in the text below:
 
The ancient Egyptian god Nun, the great unknowable and indescribable source of all the other gods, was sometimes portrayed associated with a serpent or even as a serpent. 

There is something about the image of a serpent that has led many cultures to associate it symbolically with the creation of the world and the unity of all things, especially when the serpent is represented as swallowing its own tail. In ordinary speech the word “serpent” is sometimes used interchangeably with “snake,” but a snake is an animal, while a serpent is the symbolic, mythic, sometimes dreamlike representation of that animal. Snakes do not actually swallow their tails, but serpents can do anything humans can imagine. Adapting an idea of Sheldon Glashow, 1979 Nobel laureate in physics, we turn to the multi-thousand year-old symbol of the serpent swallowing its tail and give it a modern interpretation. “Uroboros” is the ancient Greek word for a serpent swallowing its tail. We will call the symbol pictured above the “Cosmic Uroboros.” The tip of the cosmic serpent’s tail represents the smallest possible size scale, the Planck length, and its head represents the largest size scale, the size of the cosmic horizon.

The Cosmic Uroboros represents the universe as a continuity of vastly different size scales. As the image above shows, the diameter of the earth is about two orders of magnitude (10^2) smaller than that of the sun. About sixty orders of magnitude separate the very smallest from the very largest size. Traveling clockwise around the serpent from head to tail, we move from the maximum scale we can see, the size of the cosmic horizon (10^28 cm), down to that of a supercluster of galaxies, down to a single galaxy, to the distance from Earth to the Great Nebula in Orion, to the solar system, to the sun, the earth, a mountain, humans, an ant, a single-celled creature such as a bacterium, a strand of DNA, an atom, a nucleus, the scale of the weak interactions (carried by the W and Z particles), and approaching the tail the extremely small size scales on which physicists hope to find massive dark matter  particles, and on even smaller scales a Grand Unified Theory (GUT). The tip of the tail represents the smallest possible scale in the theoretical framework of quantum physics & relativity: the Planck length.  Human beings are just about at the center.

(Text slightly adapted from 

More specific information on Sheldon Glashow and his snake picture is available on these web-sites:

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