Timeline for What is so "spectral" about spectra?
Current License: CC BY-SA 2.5
10 events
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| Jul 9, 2011 at 9:04 | vote | accept | Martin Brandenburg | ||
| May 20, 2011 at 18:39 | comment | added | David White | Hi, does anyone know about the spectrum in topoi theory? I met someone named John Kennison who spoke about this at a conference recently and I wanted to figure out the origins of the term. If people think this would be better as a full question I can post it, but I didn't want another "What's so spectral" question after this great answer was given here. Kennison deals with the cyclic spectrum of a Boolean flow, which is a special case of a Cole Spectrum. He references P.T. Johnstone's "Topos Theory" which I can't find a copy of. Has anyone studied this kind of spectrum? | |
| Mar 29, 2011 at 18:30 | history | edited | Qfwfq | CC BY-SA 2.5 |
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| Mar 11, 2011 at 14:24 | comment | added | Qfwfq | @zoran: so the motivation would be different from the one I suggested (roughfly, "appearing" instead of "inspecting"), but the etymology could be the same. | |
| Jan 20, 2011 at 19:16 | comment | added | Zoran Skoda | On the other hand the etypology above is a bit misleading. The spectrum of a system is a generalization of a spectrum of a light, related to energies the same way. For the light it is well known that the spectrum has been named by Newton who was doing the experiment with prism, which he could not explain as he followed corpuscular theory of light. The meaning was apparition, for its ghostly appearance from the prism. | |
| Jan 20, 2011 at 19:04 | comment | added | Zoran Skoda | In 1920s people in topology considered "projective spectra" which were just what some now call inverse systems of toplogical spaces, whose index set is the natural numbers. Inverse system approximates its limit. Similarly spectral sequences approximate homologies. There are similarities of such definitions with the spectra in stable homotopy. | |
| May 11, 2010 at 10:39 | history | edited | Qfwfq | CC BY-SA 2.5 |
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| May 10, 2010 at 14:24 | history | edited | Qfwfq | CC BY-SA 2.5 |
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| May 10, 2010 at 14:19 | history | edited | Qfwfq | CC BY-SA 2.5 |
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| May 10, 2010 at 14:06 | history | answered | Qfwfq | CC BY-SA 2.5 |