Clock Quantum Monte Carlo: an imaginary-time method for real-time quantum dynamics

In quantum information theory, there is an explicit mapping between general unitary dynamics and Hermitian ground state eigenvalue problems known as the Feynman-Kitaev Clock. A prominent family of methods for the study of quantum ground states are quantum Monte Carlo methods, and recently the full configuration interaction quantum Monte Carlo (FCIQMC) method has demonstrated great promise for practical systems. We combine the Feynman-Kitaev Clock with FCIQMC to formulate a new technique for the study of quantum dynamics problems. Numerical examples using quantum circuits are provided as well as a technique to further mitigate the sign problem through time-dependent basis rotations. Moreover, this method allows one to combine the parallelism of Monte Carlo techniques with the locality of time to yield an effective parallel-in-time simulation technique

Negotiating the Nation: Knowledge and Meaning at Vaucluse House in its First Curatorial Period

Inaugurated during World War I, Vaucluse House museum aimed to educate visitors of the work of nineteenth century parliamentarian William Charles Wentworth, in particular his role in the installation of responsible government in New South Wales, indeed his writing of the first Constitution, for this and other Wentworth projects were among those which underpinned twentieth century democracy. This article uses museum theory concerning the character of the modern disciplinary museum, and also the tendency of that institution to shape knowledge, to investigate the experience offered to audiences at Vaucluse House over the museum’s first curatorial period. It argues that, in the context of war and an official need to press empire nationalist identity, particular curatorial practices and museological assumptions shaped the themes available and assumed certain audience responses. In the absence of any contemporary methods for assessing museum work in detail, the decision to install a major thematic display of constitutional history intermingled with a house museum interpretation produced mixed messages. Unexpected new evidence and ingenuous curatorial expansion of the rooms available for inspection soon produced unintended consequences. In a changing historical and cultural context, the major theme and rationale of the museum began to be undermined and the house museum interpretation began to dominate. It was this focus which was finally and belatedly endorsed by the museum Trustees in the mid 1950s

Computer‐based teaching and evaluation of introductory statistics for health science students: Some lessons learned

In recent years, it has become possible to introduce health science students to statistical packages at an increasingly early stage in their undergraduate studies. This has enabled teaching to take place in a computer laboratory, using real data, and encouraging an exploratory and research‐oriented approach. This paper briefly describes a hypertext Computer Based Tutorial (CBT) concerned with descriptive statistics and introductory data analysis. The CBT has three primary objectives: the introduction of concepts, the facilitation of revision, and the acquisition of skills for project work. Objective testing is incorporated and used for both self‐assessment and formal examination. Evaluation was carried out with a large group of Health Science students, heterogeneous with regard to their IT skills and basic numeracy. The results of the evaluation contain valuable lessons

How Does Leadership Structure Affect the Bottom Line?

Key Findings Investment in High-commitment HR practices lead to key employee-based outcomes. When companies invest in employees with a system of high-commitment HR practices (see examples of these practices below) they are able to build a workforce with higher human capital and motivation to exert discretionary effort for the benefit of the organization. In particular, higher use of these high-commitment HR (HCHR) practices were significantly related to higher levels of employee education, company tenure/experience, collaboration, and helping behaviors. Higher employee human capital and motivation are resources that lead to competitive advantage. In return, these employee outcomes appear to be key organizational resources for driving competitive advantage. Specifically, higher levels of employee company tenure (i.e., firm-specific experience and knowledge), collaboration, and helping behaviors were all significantly related to higher company sales growth and perceived performance (performance relative to competitors as rated by the company CEO). Leaders make a diff in the extent to which these employee-based resources lead to competitive advantage. In general, these employee-based resources were related to higher performance, but CEOs with greater levels of human capital seemed to be able to leverage these resources for even greater performance. Compared to companies with CEOs with less experience, companies with CEOs with higher average industry and company experience and higher levels of employee human capital and motivation had significantly higher performance, suggesting that CEOs with higher experience seem to understand how to take advantage of the employee-based resources that have been built through the investment in HCHR practices

Maintaining relevance: cultural diversity and the case for public service broadcasting

SBS has been the subject of some heated debates about funding models, commercial activity, perceived \u27populism\u27 and the continued relevance of publicly funded media. These debates and challenges are not unique to SBS or to Australia. Public Service Broadcasting (PSB) in many contexts is facing a \u27crisis of legitimacy\u27 as it struggles to retain audiences in the face of new technologies, rapidly globalising media, and the rejection of traditional patterns of media usage, particularly among younger generations. Debates around commercialism and the role of PSB in the market also continue in Europe, despite the plurality of models and funding arrangements. Public broadcasters have faced accusations of irrelevance. This is particularly the case in relation to cultural diversity, as old models of representation, universalism of access and nation-building are unable to keep pace with increasingly complex and diversifying societies. There is a tendency in debates around PSB to conflate traditional public broadcasting with the public sphere and all its assumed virtues of strong citizenship, public debate and informed commentary addressing a ?citizenry?, and to contrast this with bland commercial offerings and individualist consumerism (Barnett, 2003). The public service and market models are based, as least in terms of the funding and business models, on different views of the audience, but how different are the content, schedule and services provided under the two frameworks? Views of the role of public service broadcasting can be grouped into three main camps: ? Market failure ? characterised as ?liberalism with a human face?, allowing for a place for ?unpopular? services and the notion that not all niches are profitable; ? Quality and diversity of voices ? in which the perceived public interest is served by content of a range or calibre higher than that produced for profit; ? Public value and democratic principles ? the vision of a desired public culture, greater participation in public life and genuine cultural pluralism. Cultural diversity and increasingly complex relationships between citizens and national public life have the potential, along with other forms of fragmentation amongst contemporary audiences, to pose one of biggest challenges to public broadcasting in all these models. If not managed effectively and engaged with creatively, claims to ?public value?, legitimacy and relevance, as well as claims on public funds, are undermined

Increasing the representation accuracy of quantum simulations of chemistry without extra quantum resources

Proposals for near-term experiments in quantum chemistry on quantum computers leverage the ability to target a subset of degrees of freedom containing the essential quantum behavior, sometimes called the active space. This approximation allows one to treat more difficult problems using fewer qubits and lower gate depths than would otherwise be possible. However, while this approximation captures many important qualitative features, it may leave the results wanting in terms of absolute accuracy (basis error) of the representation. In traditional approaches, increasing this accuracy requires increasing the number of qubits and an appropriate increase in circuit depth as well. Here we introduce a technique requiring no additional qubits or circuit depth that is able to remove much of this approximation in favor of additional measurements. The technique is constructed and analyzed theoretically, and some numerical proof of concept calculations are shown. As an example, we show how to achieve the accuracy of a 20 qubit representation using only 4 qubits and a modest number of additional measurements for a simple hydrogen molecule. We close with an outlook on the impact this technique may have on both near-term and fault-tolerant quantum simulations

Boson Sampling for Molecular Vibronic Spectra

Quantum computers are expected to be more efficient in performing certain computations than any classical machine. Unfortunately, the technological challenges associated with building a full-scale quantum computer have not yet allowed the experimental verification of such an expectation. Recently, boson sampling has emerged as a problem that is suspected to be intractable on any classical computer, but efficiently implementable with a linear quantum optical setup. Therefore, boson sampling may offer an experimentally realizable challenge to the Extended Church-Turing thesis and this remarkable possibility motivated much of the interest around boson sampling, at least in relation to complexity-theoretic questions. In this work, we show that the successful development of a boson sampling apparatus would not only answer such inquiries, but also yield a practical tool for difficult molecular computations. Specifically, we show that a boson sampling device with a modified input state can be used to generate molecular vibronic spectra, including complicated effects such as Duschinsky rotations.Comment: 10 pages, 6 figure