Matrix product approximations to multipoint functions in two-dimensional conformal field theory

Matrix product states (MPS) illustrate the suitability of tensor networks for the description of interacting many-body systems: ground states of gapped $1$-D systems are approximable by MPS as shown by Hastings [J. Stat. Mech. Theor. Exp., P08024 (2007)]. In contrast, whether MPS and more general tensor networks can accurately reproduce correlations in critical quantum systems, respectively quantum field theories, has not been established rigorously. Ample evidence exists: entropic considerations provide restrictions on the form of suitable Ansatz states, and numerical studies show that certain tensor networks can indeed approximate the associated correlation functions. Here we provide a complete positive answer to this question in the case of MPS and $2D$ conformal field theory: we give quantitative estimates for the approximation error when approximating correlation functions by MPS. Our work is constructive and yields an explicit MPS, thus providing both suitable initial values as well as a rigorous justification of variational methods.Comment: 5 pages, 1 figure. See long companion paper arXiv:1509.07414 for full technical detail

Determining Default Probabilities for FSA Direct Loans

A binomial logit model was used to analyze relationships between financial characteristics and loan performance for FSA direct borrowers receiving direct FO or OL loans in fiscal 2005. Not surprisingly, the results indicate a strong and direct relationship between many key financial variables and probability of default. Production specialization, however, was indicated to have just as important an impact on probability of default as many financial variables. Other strong indicators included farm size, membership in a targeted group, and the ability to obtain credit from commercial lenders.FSA credit programs, loan defaults, credit risk models, risk rating, Agricultural Finance, Financial Economics,

Explaining Regional Demand for Federal Farm Credit Programs: An Ordinal Probit Approach

Demand for federally subsidized farm credit varies regionally, with farm borrowers in some regions very dependent on USDA credit programs. Counties are grouped based on their level of demand for Farm Service Agency (FSA) direct farm ownership (FO) and farm operating loans (OL). Ordinal probit techniques are applied to analyze factors influencing county-level variation in the use of the loan programs. Results suggest that counties with the highest level of demand are more likely to have a Farm Credit System branch office, are more likely to be dependent on farming, have a greater share of farms owing debt, and have fewer guaranteed FSA borrowers and racial and ethnic minorities.Agricultural Finance, Demand and Price Analysis,

The Competitiveness of Farm Credit Markets in a Deregulated Environment

Despite the proliferation of banking offices occurring since banking deregulation, about one-third of all counties in the US were still considered to have little competition with respect to agricultural credit. Counties considered less competitive were located in regions where farming is less prevalent; Northeast, Mid-Atlantic, Appalachia, and Southeast. There was no evidence that farm interest rates charged by commercial banks were higher regions with less competition. Higher FCS interest rates in counties with less competitive suggested that full-time commercial-size farms may be disadvantaged by a lack of credit market competition.Agricultural Finance,

Pharmaceutical Care for an Aging America

No abstract available

Genome Conference Offers Insights about the Future of Medicine

No abstract available

High performance forward swept wing aircraft

A high performance aircraft capable of subsonic, transonic and supersonic speeds employs a forward swept wing planform and at least one first and second solution ejector located on the inboard section of the wing. A high degree of flow control on the inboard sections of the wing is achieved along with improved maneuverability and control of pitch, roll and yaw. Lift loss is delayed to higher angles of attack than in conventional aircraft. In one embodiment the ejectors may be advantageously positioned spanwise on the wing while the ductwork is kept to a minimum

Investigations of primary and secondary impact structures on the moon and laboratory experiments to study the ejecta of secondary particles

Young lunar impact structures were investigated by using lunar orbiter, Apollo Metric and panorama photographs. Measurements on particularly homogeneous areas low in secondary craters made possible an expansion of primary crater distribution to small diameters. This is now sure for a range between 20m or = D or = 20km and this indicates that the size and velocity distribution of the impacting bodies in the last 3 billion years has been constant. A numerical approximation in the form of a 7th degree polynomial was obtained for the distribution

ANALYSIS OF BORROWER AND LENDER USE OF INTEREST ASSISTANCE ON FSA GUARANTEED FARM LOANS

The Farm Security and Rural Investment Act of 2002 made permanent the interest assistance program for the Farm Service Agency's guaranteed loans, authorized a significant increase in funding for the program, and targeted funding for beginning farmers and ranchers. The research presented here provides a basic descriptive analysis of past use. In particular, borrower data for Federal fiscal years 1985 through 2002 are examined in several dimensions. These dimensions include geographic, borrower type, lender type, interest rate differentials, percent guarantee, and the status of the loan as to whether a loss claim was paid or the loan remained active. Even though the program has been in existence for more than 15 years, little is known about its impact and utilization. This research is an initial step in documenting usage of the program.Agricultural and Food Policy, Agricultural Finance,

Femtosecond pulses and dynamics of molecular photoexcitation: RbCs example

We investigate the dynamics of molecular photoexcitation by unchirped femtosecond laser pulses using RbCs as a model system. This study is motivated by a goal of optimizing a two-color scheme of transferring vibrationally-excited ultracold molecules to their absolute ground state. In this scheme the molecules are initially produced by photoassociation or magnetoassociation in bound vibrational levels close to the first dissociation threshold. We analyze here the first step of the two-color path as a function of pulse intensity from the low-field to the high-field regime. We use two different approaches, a global one, the 'Wavepacket' method, and a restricted one, the 'Level by Level' method where the number of vibrational levels is limited to a small subset. The comparison between the results of the two approaches allows one to gain qualitative insights into the complex dynamics of the high-field regime. In particular, we emphasize the non-trivial and important role of far-from-resonance levels which are adiabatically excited through 'vertical' transitions with a large Franck-Condon factor. We also point out spectacular excitation blockade due to the presence of a quasi-degenerate level in the lower electronic state. We conclude that selective transfer with femtosecond pulses is possible in the low-field regime only. Finally, we extend our single-pulse analysis and examine population transfer induced by coherent trains of low-intensity femtosecond pulses.Comment: 25 pages, 12 figure