A Typology of Quantum Gravities – Followup on Quantum Gravity Panel

Catherine Asaro, Jay Wile, & I had a good crowd for our quantum gravity panel at Philcon: I was impressed that that many people (perhaps 40 or 50) wanted to hear about a relatively esoteric subject. Esoteric but hot: there are (right now) 663 papers on the physics archive with quantum gravity in the title, in just the last five years!
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References on Time & Time Travel

Updated 12/2/2009

Recommended popular books on time. All of the authors know their physics; none are mortal enemies of the English language.  Enjoy:
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Relativistic Morlet Wavelets

Wavelets are like musical notes: they are wave forms limited in both time and frequency. What makes them particularly useful is that any reasonable wave function may be written as a sum over them.

Usually we think of music in terms of pure tones, in terms of its Fourier components. But pure tones can be a bit too pure. For one thing, if a tone is to be completely pure it has to last forever, not a characteristic associated with practical questions. Wavelets are impure tones, and therefore a better match to the real world.
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