reconstruction of ancient Greek music

[Ancient Greek] instruments are known from descriptions, paintings and archaeological remains, which allow us to establish the timbres and range of pitches they produced.
And now, new revelations about ancient Greek music have emerged from a few dozen ancient documents inscribed with a vocal notation devised around 450 BC, consisting of alphabetic letters and signs placed above the vowels of the Greek words.
The Greeks had worked out the mathematical ratios of musical intervals – an octave is 2:1, a fifth 3:2, a fourth 4:3, and so on.
The notation gives an accurate indication of relative pitch.

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vacuum properties of QCD

ActionAPE5LQanimXs30 ChargeAPE5LQanimXs30

The animations above illustrate the typical four-dimensional structure of gluon-field configurations averaged over in describing the vacuum properties of QCD [ Quantum Chromodynamics ]. The volume of the box is 2.4 by 2.4 by 3.6 fm, big enough to hold a couple of protons. Contrary to the concept of an empty vacuum, QCD induces chromo-electric and chromo-magnetic fields throughout space-time in its lowest energy state. After a few sweeps of smoothing the gluon field (50 sweeps of APE smearing), a lumpy structure reminiscent of a lava lamp is revealed. This is the QCD Lava Lamp. The action density (left) and the topological charge density (right) are displayed. The former is similar to an energy density while the latter is a measure of the winding of the gluon field lines in the QCD vacuum.

The animation at left was featured in Prof. Frank Wilczek’s 2004 Nobel Prize Lecture.

Visualizations : Centre for the Subatomic Structure of Matter (CSSM) and Department of Physics, University of Adelaide, 5005 Australia    |    link

Devotion, Wisdom, Samadhi and Compassion

Khenchen Palden Sherab Rinpoche

 

 

 

 

 

 

Just as a precious jewel, the sky, and water are by nature pure, likewise the tathagatagarbha or dharmadhatu is by nature always free from the defilement of the mental poisons and thus utterly pure. Whereas this is the meaning of the essence, the cause that completely purifies the adventitious defilements consists of devotion towards the Mahayana Dharma, of highest discriminative or analytical wisdom realizing the non-existence of a self, of limitless samadhi endowed with bliss, and of great compassion focusing on sentient beings as its point of reference. The realization arising from these [purifying causes] is to be known as enlightenment.

Buddha Nature
The Mahayana Uttaratantra Shastra with Commentary
by Maitreya
translated by Rosemarie Fuchs    page 119

Shambhala [ publisher ] description :

All sentient beings without exception have buddha nature—the inherent purity and perfection of the mind, untouched by changing mental states. Thus there is neither any reason for conceit in deeming oneself better than others nor any reason for self-contempt, thinking of oneself as inferior and unable to reach enlightenment. This seeing is obscured by veils which are removable and do not touch the inherent purity and perfection of the nature of the mind as such. The Mahayana Uttaratantra Shastra, one of the Five Treatises said to have been dictated to Asanga by the Bodhisattva Maitreya, presents the Buddha’s definitive teachings on how we should understand this ground of enlightenment and clarifies the nature and qualities of buddhahood.

Jamgön Kongtrül Lodro Thaye (1813–1899), the profoundly learned and realized master who compiled what are known as the “Five Great Treasures,” wrote the outstanding commentary to the Mahayana Uttaratantra Shastra translated here. Called The Unassailable Lion’s Roar, it presents Maitreya’s text as a background for the Mahamudra teachings in a way that is especially clear and easy to understand.