High Energy Cosmic Neutrinos

While the general principles of high-energy neutrino detection have been understood for many years, the deep, remote geographical locations of suitable detector sites have challenged the ingenuity of experimentalists, who have confronted unusual deployment, calibration, and robustness issues. Two high energy neutrino programs are now operating (Baikal and AMANDA), with the expectation of ushering in an era of multi-messenger astronomy, and two Mediterranean programs have made impressive progress. The detectors are optimized to detect neutrinos with energies of the order of 1-10 TeV, although they are capable of detecting neutrinos with energies of tens of MeV to greater than PeV. This paper outlines the interdisciplinary scientific agenda, which span the fields of astronomy, particle physics, and cosmic ray physics, and describes ongoing worldwide experimental programs to realize these goals.Comment: 15 pages, 9 figures, talk presented at the Nobel Symposium on Particle Physics and the Universe, Sweden, August 199

Aharonov–Bohm phase shifts induced by laser pulses

An experimentally accessible scalar Aharonov–Bohm (AB)-effect is proposed using a ponderomotive potential induced by a pulsed laser. This ponderomotive AB (PAB)-effect is unique in that the time-averaged description is classified as type-I, whereas the underlying time-dependent theory is classified as type-II. Not only is the PAB-effect of fundamental interest, it may also be used to characterize ultrashort electron pulses (<100 fs), using low power femtosecond lasers, which is important for ultrafast electron diffraction and microscopy

Cyclonic spectra, cyclotomic spectra, and a conjecture of Kaledin

With an explicit, algebraic indexing $(2,1)$-category, we develop an efficient homotopy theory of cyclonic objects: circle-equivariant objects relative to the family of finite subgroups. We construct an $\infty$-category of cyclotomic spectra as the homotopy fixed points of an action of the multiplicative monoid of the natural numbers on the category of cyclonic spectra. Finally, we elucidate and prove a conjecture of Kaledin on cyclotomic complexes.Comment: 28 pages. Comments very welcom