Kinetic Energy: T or K in Mechanics/QM?

AI Thread Summary
In classical mechanics, kinetic energy is typically represented by the symbol T, while in quantum mechanics (QM), it can be denoted as either T or K. The reasons behind the different notations remain unclear and are described as shrouded in mystery. There are hints of a deeper historical context, suggesting that the choice of symbols may be linked to ancient traditions. The discussion alludes to a secretive aspect of this notation, implying that significant efforts have been made to protect this knowledge. Ultimately, the conversation highlights the ongoing intrigue surrounding the symbols used for kinetic energy in both classical and quantum mechanics.
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In classical mechanics, the kinetic energy is denoted T. Why not K? In QM the kinetic energy operator is sometimes denoted by T as well although I have seen it denoted as K.
 
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Shrouded in mystery, forgotten lore irretrievable from the hoary, ancient past..
 
We can't tell you that information yet, but we can reveal that thousands have died protecting the secret.
 
Yet some of the struggling survivors are still spilling their blood in order to keep the secret unrevealed and safe to a world which is still unprepared to face the eyes of the truth.
 
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