My paper on the Digital Restoration of Ancient Papyri has been selected by
Drives 'n' droves
The best of the rest from the physics arXiv this week
http://www.technologyreview.com/blog/arxiv/23293/
Sunday, May 1, 2011
Saturday, April 30, 2011
Egyptian faience
"Egyptian faience is a non-clay based ceramic displaying surface vitrification which creates a bright lustre of various blue-green colours. Having not been made from clay it is often not classed as pottery. It is called "Egyptian faience" to distinguish it from faience, the tin glazed pottery associated with Faenza in northern Italy. Egyptian faience, both locally produced and exported from Egypt, occurs widely in the ancient world, and is well known from Mesopotamia, the Mediterranean and in northern Europe as far away as Scotland." Wiki
Egyptian Museum, Turin.
Faience bowl blue-glazed decorated with lotus flowers and the face of the goddess Hathor, symbol of rebirth are the decoration.
Faience. Provenance unknown. New Kingdom, dynasty XVIII-XX (1350-1070 B.C.)Egyptian Museum, Turin.
Fishes and flowers
Ciotola decorata con pesci e fiori di loto
Faience azzurra con decorazioni nere, provenienza sconosciuta
Bowl decorated with fishes and flowers.
Blue faience, unknown origin.
First period of XVIII Dinasty (XV century BC)
Berlino, Aegyptisches Museum und Papyrussammling
Three-fold rotational symmetry in the decoration of this bowl.
Note the eye of the fishes at the center of the bowl.
It seems a Escher's creation!
It is amazing that very old creations (pottery and seals) show symmetry in their decorations.
Note the eye of the fishes at the center of the bowl.
It seems a Escher's creation!
It is amazing that very old creations (pottery and seals) show symmetry in their decorations.
For a discussion on symmetry of the engraved images on seals, see:
Symmetries in Images on Ancient Seals, Amelia Carolina Sparavigna
Abstract: We discuss the presence of symmetries in images engraved on ancient seals, in particular on stamp seals. Used to stamp decorations, to secure the containers from
tampering and for owner's identification, we can find seals that can be dated from Neolithic times. Earliest seals were engraved with lines, dots and spirals. Nevertheless, these very ancient stamp seals, in the small circular or ovoid space of their bases, possess bilateral and rotational symmetries. The shape of the base seems to determine the symmetries of images engraved on it. We will also discuss what could be the meaning of antisymmetry and broken symmetry for images on seals.
Abstract: We discuss the presence of symmetries in images engraved on ancient seals, in particular on stamp seals. Used to stamp decorations, to secure the containers from
tampering and for owner's identification, we can find seals that can be dated from Neolithic times. Earliest seals were engraved with lines, dots and spirals. Nevertheless, these very ancient stamp seals, in the small circular or ovoid space of their bases, possess bilateral and rotational symmetries. The shape of the base seems to determine the symmetries of images engraved on it. We will also discuss what could be the meaning of antisymmetry and broken symmetry for images on seals.
Friday, April 29, 2011
Michael Archangel and his balance
Chemistry and Materials Science Journal of Thermal Analysis and Calorimetry
Volume 62, Number 2, 579-580, DOI: 10.1023/A:1010151912165
Michael Archangel and Balance , by E. Robens
Volume 62, Number 2, 579-580, DOI: 10.1023/A:1010151912165
Michael Archangel and Balance , by E. Robens
"Michael escorts the deceased to God's throne and acts as a weigher of the soul at the Last Judgement."
Weighing of the Heart
"In Egyptian religion, the heart was the key to the afterlife. It was conceived as surviving death in the nether world, where it gave evidence for, or against, its possessor. It was thought that the heart was examined by Anubis and the deities during the Weighing of the Heart ceremony. If the heart weighed more than the feather of Maat, it was immediately consumed by the monster Ammit."
Wiki
Wiki
Egyptian Museum Torino
Four sons of Horus
Statuette dei quattro figli di Horus: Duamutef, a testa di sciacallo, Hapi, a testa di babbuino, Qebehsebuf, a testa di falco, Amset, a testa umana erano i protettori delle viscere del defunto, XXV-XXXI dinastia. Statuettes of the four sons of Horus: Duamutef, jackal headed, Hapi, baboon headed, Qebehsebuf, falcon headed, and human headed Amset, protectors of the deceased's viscera, Dinasty XXV-XXXI
(712-332 BC)
(712-332 BC)
Alcohol haze at galactic heart
BBC NEWS, Tuesday, 9 October, 2001, 14:34 GMT 15:34 UK
Alcohol haze at galactic heart
Online science editor Dr David Whitehouse
"The detection of yet more alcohol in a giant molecular cloud near the centre of our galaxy could give clues to the origin of complex organic molecules in space.Astronomers have long been seeking evidence of this particular alcohol to help explain how these life-promoting substances got started. ... Vinyl alcohol, actually a non-inebriating complex organic molecule, is an important part of many chemical reactions on Earth, and the last of the three stable members of the C2H4O group of molecules to be discovered in interstellar space. It was detected in a massive molecular cloud called Sagittarius B2, located 26,000 light-years from Earth, near the centre of our galaxy....The specific radio signature of vinyl alcohol was first detected using a 12-metre radio telescope during May and June of 2001. Results from the observations will soon be published in Astrophysical Journal Letters. Of the approximately 125 molecules so far detected in interstellar space, scientists believe that most are formed by a simple process in which smaller molecules (and occasionally atoms) stick together after they collide. Since the 1970s, scientists have speculated that molecules could form on the microscopic dust grains that drift in interstellar clouds. These dust grains are thought to trap the fast-moving molecules. The surface of these grains could act as a catalyst enabling the chemical reactions that form vinyl alcohol and other complex molecules. "Scientists speculate that since the dust lies near an area where young stars are forming, the energy from these stars could evaporate the icy surface layers of the grains, liberating the molecules from their chilly nurseries, depositing them into interstellar space where they can be detected by sensitive radio antennae on Earth.
Alcohol haze at galactic heart
Online science editor Dr David Whitehouse
"The detection of yet more alcohol in a giant molecular cloud near the centre of our galaxy could give clues to the origin of complex organic molecules in space.Astronomers have long been seeking evidence of this particular alcohol to help explain how these life-promoting substances got started. ... Vinyl alcohol, actually a non-inebriating complex organic molecule, is an important part of many chemical reactions on Earth, and the last of the three stable members of the C2H4O group of molecules to be discovered in interstellar space. It was detected in a massive molecular cloud called Sagittarius B2, located 26,000 light-years from Earth, near the centre of our galaxy....The specific radio signature of vinyl alcohol was first detected using a 12-metre radio telescope during May and June of 2001. Results from the observations will soon be published in Astrophysical Journal Letters. Of the approximately 125 molecules so far detected in interstellar space, scientists believe that most are formed by a simple process in which smaller molecules (and occasionally atoms) stick together after they collide. Since the 1970s, scientists have speculated that molecules could form on the microscopic dust grains that drift in interstellar clouds. These dust grains are thought to trap the fast-moving molecules. The surface of these grains could act as a catalyst enabling the chemical reactions that form vinyl alcohol and other complex molecules. "Scientists speculate that since the dust lies near an area where young stars are forming, the energy from these stars could evaporate the icy surface layers of the grains, liberating the molecules from their chilly nurseries, depositing them into interstellar space where they can be detected by sensitive radio antennae on Earth.
Dark matter and galactic haze
"Annihilating dark matter at the heart of the Milky Way could account for signals detected by two space telescopes, according to a pair of US physicists. If true, the theory provides a new indirect measurement of one of astronomy's most elusive entities. However, some physicists believe that we don't know enough about the galactic core – or dark matter – to come to this conclusion."
Does dark matter link gamma rays to galactic haze? - physicsworld.com
Transparent materials for solar energy
"Researchers in the US have developed a new kind of organic solar cell that converts a small but significant fraction of the sunlight that falls onto it into electricity, while still allowing most of the visible part of that light to pass through. Thanks to this transparency, the team says that the cell could be mounted onto windows in buildings or cars in order to tap a currently under-exploited source of energy."
Spherical symmetry
Da un libro sulle simmetrie