Efficient quantum algorithms for simulating sparse Hamiltonians

We present an efficient quantum algorithm for simulating the evolution of a sparse Hamiltonian H for a given time t in terms of a procedure for computing the matrix entries of H. In particular, when H acts on n qubits, has at most a constant number of nonzero entries in each row/column, and |H| is bounded by a constant, we may select any positive integer $k$ such that the simulation requires O((\log^*n)t^{1+1/2k}) accesses to matrix entries of H. We show that the temporal scaling cannot be significantly improved beyond this, because sublinear time scaling is not possible.Comment: 9 pages, 2 figures, substantial revision

Asteroseismology of massive stars with the TESS mission: the runaway Beta Cep pulsator PHL 346 = HN Aqr

We report an analysis of the first known Beta Cep pulsator observed by the TESS mission, the runaway star PHL 346 = HN Aqr. The star, previously known as a singly-periodic pulsator, has at least 34 oscillation modes excited, 12 of those in the g-mode domain and 22 p modes. Analysis of archival data implies that the amplitude and frequency of the dominant mode and the stellar radial velocity were variable over time. A binary nature would be inconsistent with the inferred ejection velocity from the Galactic disc of 420 km/s, which is too large to be survivable by a runaway binary system. A kinematic analysis of the star results in an age constraint (23 +- 1 Myr) that can be imposed on asteroseismic modelling and that can be used to remove degeneracies in the modelling process. Our attempts to match the excitation of the observed frequency spectrum resulted in pulsation models that were too young. Hence, asteroseismic studies of runaway pulsators can become vital not only in tracing the evolutionary history of such objects, but to understand the interior structure of massive stars in general. TESS is now opening up these stars for detailed asteroseismic investigation.Comment: accepted for ApJ

Technology Estimating: A Process to Determine the Cost and Schedule of Space Technology Research and Development

NASA is investing in new technologies that include 14 primary technology roadmap areas, and aeronautics. Understanding the cost for research and development of these technologies and the time it takes to increase the maturity of the technology is important to the support of the ongoing and future NASA missions. Overall, technology estimating may help provide guidance to technology investment strategies to help improve evaluation of technology affordability, and aid in decision support. The research provides a summary of the framework development of a Technology Estimating process where four technology roadmap areas were selected to be studied. The framework includes definition of terms, discussion for narrowing the focus from 14 NASA Technology Roadmap areas to four, and further refinement to include technologies, TRL range of 2 to 6. Included in this paper is a discussion to address the evaluation of 20 unique technology parameters that were initially identified, evaluated and then subsequently reduced for use in characterizing these technologies. A discussion of data acquisition effort and criteria established for data quality are provided. The findings obtained during the research included gaps identified, and a description of a spreadsheet-based estimating tool initiated as a part of the Technology Estimating process

Evidence review of the potential wider impacts of climate change mitigation options: agriculture, forestry, land use and waste sectors

A report prepared for Scottish Government. Greenhouse gas (GHG) mitigation is a central policy objective in Scotland. The Climate Change (Scotland) Act 2009 sets an interim 42% reduction target for 2020 and an 80% target for 2050 across all sectors of society (1990 baseline). As a priority policy area, it has become vital to better understand the co-benefits and adverse impacts arising from mitigation actions on our environment, economy and society. Integrated assessment is key in prioritising environmental actions, reducing adverse impacts and enhancing positive co-effects. This report aims to summarise evidence on the wider impacts (WI) of GHG mitigation options (MO) in the Agriculture, land use, land use change and forestry sectors (ALULUCF) and those related waste management. The key findings of the review, are a summary of the wider impacts and an overview of the challenges in quantifying and monetising these impacts

The 8th Annual School of Music Collage Concert

Kennesaw State University School of Music presents The 8th Annual School of Music Collage Concert.https://digitalcommons.kennesaw.edu/musicprograms/1370/thumbnail.jp

Determination of selenium in serum in the presence of gadolinium with ICP-QQQ-MS

Gadolinium (Gd)-based magnetic resonance imaging (MRI) contrasting agents interfere with the determination of selenium (Se) when analysed by single quadrupole inductively coupled plasma-mass spectrometry (ICP-MS). This paper demonstrates that an ICP-triple quadrupole-MS (ICP-QQQ-MS) with oxygen mass shift overcomes Gd++ interference on Se+ and mitigates typically encountered matrix and spectral based interferences. Normal human serum was diluted in a solution containing isopropanol, EDTA, NH4OH and Triton X-100. Samples were unspiked (control) serum; serum spiked with 0.127 μmol L−1 Se or 127 μmol L−1 Gd; and serum spiked with both 0.127 μmol L−1 Se and 127 μmol L−1 Gd. Consideration of collision/reaction gases and conditions for interference mitigation included helium (He); a ‘low’ and ‘high’ hydrogen (H2) flow, and oxygen (O2). The instrument tune for O2 was optimised for effective elimination of interferences via a mass shift reaction of Se+ to SeO+. The ICP-QQQ-MS was capable of detecting trace (>9.34 nmol L−1) levels of Se in serum in the presence of Gd in our simulated post-MRI serum sample. The multi-tune capabilities of the ICP-QQQ-MS may be adapted to eliminate other specific isobaric interferences that cause false positive results in other analyses where the analyte is confounded by doubly charged and/or polyatomic species