The object of this project is to present a novel digital audio effect based on a real-time, windowed block-based FFT and inverse FFT. The effect is achieved by mirroring the spectrum, producing a sound effect ranging from a purer rendition of the original, through a rougher one, to a sound unrecognisable from the original. A mirror taking the shape of a conic section is constructed between cert...

Focusing optics based on Wolter optical geometries developed for x-ray grazing incidence beams can be designed for neutron beams. Wolter optics are formed by grazing incidence reflections from two concentric conic sections (for example, a paraboloid and a hyperboloid). This has transformed observational X-ray astronomy by increasing the sensitivity by many orders of magnitude for research in as...

Quantum fluctuations of electromagnetic radiation pressure are discussed. We use an approach based on the quantum stress tensor to calculate the fluctuations in velocity and position of a mirror subjected to electromagnetic radiation. Our approach reveals that radiation pressure fluctuations are due to a cross term between vacuum and state dependent terms in a stress tensor operator product. Th...

HeNe ring-laser gyros are standard sensors in inertial guidance; mirror reflectances now reach 99.9999%. Present research instruments have an area of ∼ 1 m2, a passive quality factor of > 1011, and a resolution of the frequency difference of counter-rotating optical beams approaching microhertz. In the Sagnac effect, this difference is proportional to the angular velocity. Present resolution is...

We report experimental observations of a large Bragg reflection from arrays of cold atoms trapped near a one-dimensional nanoscale waveguide. By using an optical lattice in the evanescent field surrounding a nanofiber with a period nearly commensurate with the resonant wavelength, we observe a reflectance of up to 75% for the guided mode. Each atom behaves as a partially reflecting mirror and a...

Body dysmorphic disorder is a severe disturbance in which the person is preoccupied with an imagined defect in appearance. It is unclear what causes and what maintains BDD, although it is assumed that patients are characterized by an increased self-focused attention. Since patients spend a lot of time examining their 'defect' in reflecting surfaces, it might well be that mirror gazing itself is...

Understanding the intentions of others presumably involves a human analog of the mirror neuron system. A putative marker of such mirror activity is the suppression of electroencephalographic oscillations in the 8-12 Hz range, which, when recorded over somatosensory areas, is associated with motor activity and labeled μ rhythms. We investigated whether μ-suppression can be modulated by attention...

This report outlines the possibilities to be found using one or more diffraction-limited high-quality light beams to activate a weakly absorbing gas in a regime where the diffraction spread can be controlled by converging optical devices to within a ratio ofJ2 of the minimum at the beam waist (corresponding lengths between converging elements are within twice the Rayleigh range). Our desigr.s u...

An x-ray beam with energy of 20.5 keV has been efficiently focused down to a spot size as small as 90 nm390 nm by a Kirkpatrick–Baez reflecting mirrors device. The first mirror, coated with a graded multilayer, plays both the role of vertical focusing device and monochromator, resulting in a very high flux s231011 photons/sd and medium monochromaticity sDE /E,10−2d. Evaluation of the error cont...