One-Loop Effective Potential

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Quark-antiquark potential in AdS at one loop

Quark-antiquark potential in AdS at one loop

AdS/CFT system [12, 13], is in general a hard mathematical problem. The task is simplified considering scaling limits of some “semiclassical parameters”, as in the case of fluctuations over the open string solution dual to the cusp Wilson loop [14, 15, 16], or the closed string solutions of [17, 18, 19, 20]. In these limits the solutions become linear in the world-sheet coordinates (τ, σ), thus making constant the coefficients in the fluctuation Lagrangian. In the case of the Wilson loop of a pair of anti-parallel lines, which has no other parameters than the distance between the lines, the complicated σ-dependence of the lagrangean coefficients makes non-trivial the evaluation of the operator spectra. The same is true for the straight line and circular Wilson loops [8, 9, 21], for which a first explicit computation of fluctuation determinants has been carried out in [22]. There, based on the effective one-dimensionality of the spectral problem, it was possible to trade the explicit evaluation of the eigenvalue spectrum for the relevant operator with the resolution of the associated differential equation, an approach known as Gelfand-Yaglom method [23, 24]. In an analogous fashion the case of the anti-parallel lines has been studied in [10], where each functional determinant has been formally expressed in terms of the associated initial value problem with Dirichlet boundary conditions (the appropriate ones in this framework [25]). While the possibility of a completely analytical treatment of such initial value problem was not recognized in [10], the coefficient a 1 in (1.2) was worked out by the
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An effective thermodynamic potential from the instanton vacuum with the Polyakov loop

An effective thermodynamic potential from the instanton vacuum with the Polyakov loop

iv) Additional T dependence can be added to the instanton distribution function, according to the fermion overlap matrix, if one considers full QCD in computing the distribution function [43], being di ff erent from the present talk based on the variational method in pure-glue QCD (the Harrington- Shepard caloron) [31]. Moreover, the instanton clustering, which was suggested as a main contribution for the chiral phase transition [43, 44] and not taken into account here, may be responsible for lowering T c χ .

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Electromagnetic Structure and Reactions of Few-Nucleon Systems in χEFT

Electromagnetic Structure and Reactions of Few-Nucleon Systems in χEFT

Abstract. We summarize our recent work dealing with the construction of the nucleon-nucleon potential and associated electromagnetic currents up to one loop in chiral effective field theory (χEFT). The magnetic dipole operators derived from these currents are then used in hybrid calculations of static properties and low-energy ra- diative capture processes in few-body nuclei. A preliminary set of results are presented for the magnetic moments of the deuteron and trinucleons and thermal neutron captures on p, d, and 3 He.

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Two loop effective potential for langleA2μrangle in the Landau gauge in quantum chromodynamics

Two loop effective potential for langleA2μrangle in the Landau gauge in quantum chromodynamics

Quantum chromodynamics, (QCD), is widely accepted as the quantum field theory of the nucleon partons known as quarks and gluons. At high energy, perturbation theory provides an excellent description of the phenomenology of hadron physics from, say, the point of view of deep inelastic scattering. Although the physics of QCD at low energies is not as well understood, it is generally accepted that quarks are confined and the perturbative vacuum, which is used for higher energy QCD calculations, is unstable, [1, 2, 3, 4]. To probe the infrared r´egime from the field theoretic point of view several formalisms have been developed. One in particular makes use of the operator product expansion and sum rules where the effect of dimension four operators such as (G a µν ) 2 are incorporated, [5]. Such operators have non-zero vacuum expectation values and can
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Two-dimensional S-matrices from unitarity cuts

Two-dimensional S-matrices from unitarity cuts

Of course, this need not be the case for the original bubble integrals before cutting – due to factors of loop-momentum in the numerators. These divergences, along with those coming from tadpole graphs, which we did not consider, should be taken into account for the renormalization of the theory. In this paper we do not investigate this issue, however all the theories we consider in Section 3 and 4 are either UV-finite or renormalizable. Furthermore, whether the cut-constructible contribution (2.13)/(2.17) to the S-matrix gives the full result is a priori unclear as rational terms following from non-trivial cancellations in the regularization procedure may be missing.
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One-loop spectroscopy of semiclassically quantized strings: bosonic sector

One-loop spectroscopy of semiclassically quantized strings: bosonic sector

It seems advantageous to consider α ∈ C as the independent parameter and therefore Ω as a doubly periodic function of α as in (4.3). There should exist four values of α, which correspond to one value of Ω. To be more precise, for the physical spectrum we are looking for all values of α, which correspond to a real Ω 2 . The analysis of Appendix B.1 is devoted to this study, and is nicely summarized in Fig. 1 where in the complex α plane the lines where Ω 2 (α) is real are plotted. The “physical” four linear independent solutions of the fourth order differential operator (2.15) live on these lines, and in the fundamental domain represented in Fig. 2 they correspond to the different colours. In the following let 0 < k < 1/ √ 2. The case 1/ √ 2 < k < 1 can be obtained by applying the duality transformation of Appendix B.2 on the following results.
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Density functional embedding for periodic and non-periodic diffusion Monte Carlo calculations

Density functional embedding for periodic and non-periodic diffusion Monte Carlo calculations

making the connection with different high-level approaches comparatively easy. It should be kept in mind, however, that DFET calculations are not self-consistent in the sense that the embedding potential V emb does not react to the improved cluster density ρ cluster X [except for a first-order correction, see Eq. (10)]. Instead, the embedding potential is only determined once, at a pure DFT level. This is in contrast to iterative wave-function/DFT schemes, which have been proposed as an extension to freeze and thaw FDE algorithms [57]. In these wave-function/DFT schemes, the embedding potential is constructed self-consistently for a cluster described by a wave-function method and an environment described by DFT. Extending these wave-function/DFT schemes to DMC/DFT might, however, be nontrivial since the system density, which enters the iteratively improved embedding potential in these schemes, is only sampled stochastically in DMC. Although smooth representations of the density can be obtained by projecting onto basis functions [58] or by sampling in discrete Fourier space, it remains questionable and a matter of future in- vestigation whether these representations can be made accurate enough. Previous “DMC”/DFT applications were therefore based on embedding potentials that were self-consistently created at a mixed CASPT2/DFT level [26] making the extension to periodic systems challenging. Similar concerns also hold true for potential functional embedding theory [25], which would also allow for a self-consistent embedding at a wave-function/DFT level. At present, and in spite of its restrictions, we therefore view DFET to be the most suitable embedding scheme if a connection to DMC is sought for solid-state systems.
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On one loop correction to energy of spinning strings in S(5)

On one loop correction to energy of spinning strings in S(5)

In the ! 1 limit the one-loop energy correction must go to zero because this strict limit is essentially like a BPS limit — the bosonic and fermionic contributions should then cancel against each other due to supersymmetry. 2 This implies that only negative powers of can appear in the large -expansion of E 1 . Indeed, examining the functions a x with a > 1 one can show that the one- loop correction does have the large expansion as given in (5).

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Electroweak chiral Lagrangians and the Higgs properties at the one-loop level

Electroweak chiral Lagrangians and the Higgs properties at the one-loop level

In the first case, the two WSRs imply M V < M A and determine F V and F A in terms of the resonance masses [8, 9, 14, 21]. In the second case, it is not possible to extract a definite prediction with just the 1st WSR but one can still derive the inequality above if one assumes a similar mass hierarchy M V < M A . On the other hand, this inequality flips direction if M A < M V or turns into an equality in

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<p>Mitochondrial DNA D-loop sequencing reveals obesity variants in an Arab population</p>

<p>Mitochondrial DNA D-loop sequencing reveals obesity variants in an Arab population</p>

About 1,200 bp of mtDNA D-loop region was sequenced using primers listed in Table 1. Genomic DNA (25 ng) was subjected to PCR ampli fi cation in a fi nal volume of 25 μ L using GoTaq® Green Master Mix, 2X (Promega, USA) and 5 pmol of each primer in the corresponding ampli fi ca- tion reactions. The reaction was performed using Veriti® Thermal Cyclers (Applied Biosystems, USA) with the following conditions: 5 mins at 95°C initial denaturation for 1 cycle, 35 cycles of 45 sec at 95°C, 45 sec at 58°C and 72°C for 1 min, followed by a fi nal cycle for complete extension for 7 mins at 72°C. Reactions were allowed to stay at 4°C hold step prior to either agarose gel analysis for product QC assessment or for the proceeding
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The ξ/ξ2nd ratio as a test for Effective Polyakov Loop Actions

The ξ/ξ2nd ratio as a test for Effective Polyakov Loop Actions

The first requirement is that Polyakov loop correlators extracted from EPL models should display the so-called “Lüscher term” [23], i.e. a 1/R correction in the static quark-antiquark potential. Such term is present in the confining phase of the original theory, and has been detected and precisely measured on the lattice in SU(N) gauge theories, both using Wilson loops [24] and Polyakov loop correlators [25–28]; thus, EPL actions should reproduce the same behaviour. This is indeed a very non-trivial requirement, since such a term is typical of extended gauge invariant observables and, in general, spin models with short-distance interactions do not possess such a behaviour.
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A single base permutation in any loop of a folded intramolecular quadruplex influences its structure and stability

A single base permutation in any loop of a folded intramolecular quadruplex influences its structure and stability

into an unusual conformation possessing three G-tetrads linked by TTA loops. The first loop is a propeller loop while the second and third loops are transverse loops. Using Circular Dichroism (CD) spectroscopy, we have investigated the effect of sequence context on the structures and stabilities of intramolecular G-quadruplexes re- lated to the human telomere sequence by con- sidering all permutations of T and A within the loops. The results indicate that changing only one base in any one loop can have a dramatic effect on the conformation of the quadruplex as well as its melting temperature, T m . Thus, each
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Cache partitioning + loop tiling: A methodology for effective shared cache management

Cache partitioning + loop tiling: A methodology for effective shared cache management

Moreover, an evaluation over gcc 4.8.4 compiler has been performed, in terms of main memory data accesses, perfor- mance and energy consumption (Table II). We have used four cores and eight loop kernels. Six different thread com- binations have been used with three different input sizes (Table II). The thread combination numbers correspond to (1,2,3,4,5,6,7,8)=(mmm, mvm, symm, fir, gesumv, seidel, doit- gen, gauss). The first and the fourth kernel combinations en- gender a higher cache pressure and they produce the smallest ddr access gain values and consequently the smallest speedup and energy gain values. This is because in the first and fourth cases, the three most data dominant kernels (doitgen, symm, mmm) run on a different core and thus they compete to each other for cache space. On the other hand, on the other combinations two of the three above kernels use the same core and thus only the two kernels compete to each other for cache space.
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Confinement, Monopoles and Gauge Invariance

Confinement, Monopoles and Gauge Invariance

As for strategy 2) what one needs is a reliable way to detect monopoles in lattice config- urations in order to determine numerically from them the effective potential. The way this is done is by measuring the magnetic flux of the abelian field in the colour direction of the ef- fective Higgs field: excess of magnetic flux through a plaquette is interpreted as Dirac string of a monopole[15]. If one repeats this game in different abelian projections and compares, the result is rather disturbing: the number and the location of monopoles strongly depend on the abelian projection. The existence of a monopole seems to be a gauge dependent concept. In this paper we discuss these issues and in particular we show that the existence or the creation of a monopole is a gauge invariant, AP independent concept [Sect. 2]. This legitimates the construction of µ used to implement strategy 1) and the idea that all choices for effective Higgs field are equivalent [5].
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Bistable systems with stochastic noise: virtues and limits of effective one-dimensional Langevin equations

Bistable systems with stochastic noise: virtues and limits of effective one-dimensional Langevin equations

We first impose stochastic forcing of the same intensity on the freshwater forcings to the two high-latitude boxes and observe that the resulting pdf of the thermohaline circulation strength is bimodal and symmetric. More importantly, for both models the dynamics of q can be accurately described with a Langevin equation with a drift term derived from a one-dimensional effective potential plus stochastic noise. An excellent approximation to the true dynamics (as well as to the hopping rates) can be obtained in an explicit form by im- posing that the sum of the densities of the two high-latitude boxes is a slow variable. The main difference between the two is that in the full model the nonlinear feedbacks acting on the variable we are neglecting alter in a nontrivial, non- linear way the effective surrogate noise acting on the q vari- able. In other terms, in the case of the full model a careful tuning of the noise allows for taking care very accurately – in a statistical sense – of the effect of all the variables we are neglecting. Our results are obtained for a specific value
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Cache Partitioning + Loop Tiling: A Methodology for Effective Shared Cache Management

Cache Partitioning + Loop Tiling: A Methodology for Effective Shared Cache Management

elements in main memory in order; new arrays are created which replace the default ones (an extra loop kernel is added), b) the number of the loops being tiled is increased (the number of the extra loops being inserted equals to the number of the loops being tiled), c) smaller tile sizes are selected (the number of loop iterations is increased). The constraint (a) gives by far more arithmetical instructions than (b) and (c). Thus, the schedules are classified according to the number of addressing instructions, that is, how many of the (a)-(c) constraints they meet. This way, we can find the schedule giving the smallest number of arithmetical instructions. By iteratively applying the above procedure for all the different mappings between threads-cores, we can find the best mapping (in terms of main memory accesses), i.e., what threads run on each core.
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Mast Cells Interact with Endothelial Cells to Accelerate In Vitro Angiogenesis

Mast Cells Interact with Endothelial Cells to Accelerate In Vitro Angiogenesis

endothelial cells with mast cells (Figure 2A) was more effective in inducing tube and loop formation.. 85.[r]

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Redenomination: Why is It Effective in One Country but Not in Another?

Redenomination: Why is It Effective in One Country but Not in Another?

The real impact of redenomination in a country is a topic that invites many dissenting arguments. Redenomination policy is a policy that is implemented by the government to change the denomination values of their currency by a certain ratio (Dogarawa, 2007). As an example, in 1983, Argentina implemented a redenomination policy that changed the denomination value of 1000 Peso into 1 Peso, without changing its real exchange rate (Mosley, 2005). In general, redenomination is considered to be symbolic, however based on previous cases, redenomination can become one of the factors that can improve a country’s economy. In contrast, redenomination is not effective in some countries, as persistence hyperinflation causes the currency to naturally get back to the old denomination values. In Section 2, we will discuss further regarding redenomination theories. Why does a country implement redenomination policy, and what was the impact of the policy? Furthermore, we will discuss arguments and results that support the implementation of the policy. Of course, we are going to talk about arguments and results that are against redenomination as well.
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One-particle reducibility in effective scattering theory

One-particle reducibility in effective scattering theory

that every interim propagator is really presented it the chain. This is not always the case in e ff ective theory just because some of them might be "killed" by the corresponding factors stemming from the adjacent vertices. This leads to a mishmash of orders in the perturbation theory based on the loop counting. Also, as shown above, this prevents one to obtain finite S-matrix elements with the help of finite number of RP’s.

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Quantizing three spin string solution in AdS(5) xS**5

Quantizing three spin string solution in AdS(5) xS**5

One can check that the 1-loop correction vanishes in the “point-particle” limit k = 0, in agreement with the non-renormalization of the energy of this BPS state dual to a gauge theory operator with protected conformal dimension [1]. In what follows we shall set k = 1. We would like to compute (4.2) as an expansion in 1 κ in the large κ limit. In the large κ limit there will be also exponentially small terms which we shall disregard. To estimate the value of the sums we shall approximate them by integrals as explained in Appendix C. As discussed in Appendices A and B, the bosonic and fermionic frequencies ω n,i B and ω F
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