Open Access. Powered by Scholars. Published by Universities.®
Cosmology, Relativity, and Gravity Commons™
Open Access. Powered by Scholars. Published by Universities.®
Articles 1 - 2 of 2
Full-Text Articles in Cosmology, Relativity, and Gravity
Phase Shift Sequences For An Adding Interferometer, Peter Hyland, Brent Follin, Emory F. Bunn
Phase Shift Sequences For An Adding Interferometer, Peter Hyland, Brent Follin, Emory F. Bunn
Physics Faculty Publications
Cosmic microwave background (CMB) polarimetry has the potential to provide revolutionary advances in cosmology. Future experiments to detect the very weak B-mode signal in CMB polarization maps will require unprecedented sensitivity and control of systematic errors. Bolometric interferometry may provide a way to achieve these goals. In a bolometric interferometer (or other adding interferometer), phase shift sequences are applied to the inputs in order to recover the visibilities. Noise is minimized when the phase shift sequences corresponding to all visibilities are orthogonal. We present a systematic method for finding sequences that produce this orthogonality, approximately minimizing both the length of …
The Kinematic Origin Of The Cosmological Redshift, Emory F. Bunn, David W. Hogg
The Kinematic Origin Of The Cosmological Redshift, Emory F. Bunn, David W. Hogg
Physics Faculty Publications
A common belief about big-bang cosmology is that the cosmological redshift cannot be properly viewed as a Doppler shift (that is, as evidence for a recession velocity), but must be viewed in terms of the stretching of space. We argue that, contrary to this view, the most natural interpretation of the redshift is as a Doppler shift, or rather as the accumulation of many infinitesimal Doppler shifts. The stretching-of-space interpretation obscures a central idea of relativity, namely that it is always valid to choose a coordinate system that is locally Minkowskian. We show that an observed frequency shift in any …