scholarly journals Multi-critical point principle as the origin of classical conformality and its generalizations

2021 ◽  
Author(s):  
Hikaru Kawai ◽  
Kiyoharu Kawana
Keyword(s):  
Critical Point ◽  
Critical Points ◽  
Effective Potential ◽  
Vacuum Expectation ◽  
High Energy ◽  
Low Energy ◽  
Coupling Constants ◽  
The Other ◽  
Fine Tuning ◽  
General Scalar

Abstract Multi-critical point principle (MPP) is one of the interesting theoretical possibilities that can explain the fine-tuning problems of the Universe. It simply claims that “the coupling constants of a theory are tuned to one of the multi-critical points, where some of the extrema of the effective potential are degenerate.” One of the simplest examples is the vanishing of the second derivative of the effective potential around a minimum. This corresponds to the so-called classical conformality, because it implies that the renormalized mass m2 vanishes. More generally, the form of the effective potential of a model depends on several coupling constants, and we should sweep them to find all the multi-critical points. In this paper, we study the multi-critical points of a general scalar field φ at one-loop level under the circumstance that the vacuum expectation values of the other fields are all zero. For simplicity, we also assume that the other fields are either massless or so heavy that they do not contribute to the low energy effective potential of φ. This assumption makes our discussion very simple because the resultant one-loop effective potential is parametrized by only four effective couplings. Although our analysis is not completely general because of the assumption, it still can be widely applicable to many models of the Coleman-Weinberg mechanism and its generalizations. After classifying the multi-critical points at low-energy scales, we will briefly mention the possibility of criticalities at high-energy scales and their implications for cosmology.

Instability Study of Repetitive Nanosecond Pulsed Discharge Plasma in a Plasma Assisted Burner

2020 ◽  
Author(s):  
Saeid Zare ◽  
Omid Askari
Keyword(s):  
High Velocity ◽  
Discharge Plasma ◽  
Diffusion Flames ◽  
High Energy ◽  
Discharge Voltage ◽  
Low Energy ◽  
Peak Discharge ◽  
The Other ◽  
Other Hand ◽  
Point To Point

Abstract High velocity flows, as in aerospace applications require special techniques to stabilize and ignite diffusion flames. Some techniques focus on changing parameters like geometry, conditions of the flow, or fuel composition, but these techniques are usually too expensive or impossible due to major changes in the system. On the other hand, some techniques focus on generating a region of charged/excited species and active radicals upstream of the flame. That can substantially enhance the flame stability even under high strain rate or at lean-limit-flammability conditions. Repetitive nanosecond pulsed (RNP) discharge plasma is a nonthermal plasma technique with some remarkable potential to improve stability and ignitability of high velocity diffusion flames. This technique was used in previous papers in a plasma assisted coaxial inverse diffusion burner and showed some promising results by reducing the lift-off height and delaying detachment and blowout conditions. This burner is prepared to employ the discharges at the burner nozzle and simulate a single element of a multi-element methane burner. However, effectiveness of high-voltage high-frequency RNP plasma was limited by the mode of the discharge. During the tests, three different modes were observed at different combinations of plasma and flow conditions. These three modes are low energy corona, uniformly distributed plasma, and high-energy point-to-point discharge. Among these three, only well-distributed plasma significantly improved the flame. In other cases, plasma deployment was either ineffective or in some cases adversely affected the flame by producing undesirable turbulence advancing blow out. As a result, a comprehensive study of these modes is required. In this work, the transition between these three modes in a jet flame was discussed. It has been expressed as a function of plasma conditions, i.e. peak discharge voltage and discharge frequency. It was shown that increasing flow speed delays increases the voltage and frequency at which transition occurs from low-energy corona discharge to well distributed plasma discharge. Subsequently, the effective plasma conditions are thinned. On the other hand, by increasing the frequency of nanosecond discharges, the chance of unstable point-to-point discharges is decreased. In contrast, the discharge peak voltage causes two different consequences. If it is too low, the pulse intensity is too week that the system will experience no visible plasma discharges or the discharges will not pass the low-energy corona, no matter how high the frequency is. If too high, it will enhance the chance of point-to-point discharges and limits the stabilization outcome of the system. Therefore, an optimal region is found for peak discharge voltage.

scholarly journals THE MIRAGE OF THE FERMI SCALE

2013 ◽  
Vol 28 (32) ◽  
pp. 1350140 ◽  
Author(s):  
OLEG ANTIPIN ◽  
FRANCESCO SANNINO ◽  
KIMMO TUOMINEN
Keyword(s):  
Model Building ◽  
Hadron Collider ◽  
High Energy ◽  
Low Energy ◽  
The Other ◽  
Electroweak Symmetry ◽  
Light Higgs Boson ◽  
Very High Energy ◽  
Very High ◽  
Natural Way

The discovery of a light Higgs boson at Large Hadron Collider may be suggesting that we need to revise our model building paradigms to understand the origin of the weak scale. We explore the possibility that the Fermi scale is not fundamental but rather a derived one, i.e. a low energy mirage. We show that this scenario emerges in a very natural way in models previously used to break the electroweak symmetry dynamically and suggest a simple dynamical framework for this idea. In our model the electroweak scale results from the interplay between two very high energy scales, one typically of the order of Λ UV ~ 1010 GeV and the other around MU ~ 1016 GeV , although other values are also possible.

The efficiency of food utilization for egg production by pullets

1958 ◽  
Vol 50 (1) ◽  
pp. 97-101 ◽  
Author(s):  
W. Bolton
Keyword(s):  
Egg Production ◽  
High Energy ◽  
Metabolizable Energy ◽  
Low Energy ◽  
The Other ◽  
Food Utilization ◽  
Digestible Energy ◽  
Digestible Protein ◽  
The Cost ◽  
Low Energy Diet

1. The efficiency of food utilization for egg production by pullets has been determined for two diets, one high in energy and the other low.2. Both groups laid at the same rate (245 eggs/bird) throughout the year.3. Birds fed the low-energy diet ate more food, but the intakes of digestible protein, non-protein digestible energy and metabolizable energy were the same for both groups.4. The cost of food perton was higher for the high-energy diet; per bird per year it was the same for both groups.

A sputter source for electron microscopic preparation

1978 ◽  
Vol 36 (1) ◽  
pp. 150-151 ◽  
Author(s):  
E. Jakopić ◽  
A. Brunegger ◽  
R. Essl ◽  
G. Windisch
Keyword(s):  
Discharge Chamber ◽  
High Energy ◽  
Low Energy ◽  
The Other ◽  
Ion Current ◽  
Electron Microscopic ◽  
Neutral Particles ◽  
Fine Grained ◽  
Sputtering Yields

Coating electron microscopic specimens by sputtering yields particulary fine grained coatings of strong adherence. Two methods have been applied up to now. Their difference lies in the arrangement of target and specimen. If, in one case both, target and specimen are arranged inside the discharge chamber,damage by the discharge of sensitive specimens is possible (Fig.la). If, in the other case both, target and specimen are arranged outside the discharge chamber, focussing of the ions is necessary, above all for shadowing (Fig.lb).Simple ion guns of low energy (some keV) however, yield a relatively low ion current, so that coatings with materials which are difficult to sputter, such as tungsten, can hardly be produced. With ions of higher energy the gain of sputtering particles would certainly increase. However, the danger arises that ions scattered at the target and neutral particles of high energy could damage the specimen.The basic idea of the new sputter source consists of arranging the target inside the discharge chamber but the specimen outside of it (Fig.2).

scholarly journals PROBING THE EFFECTIVE NUCLEON-NUCLEON INTERACTION AT BAND TERMINATION

2007 ◽  
Vol 16 (02) ◽  
pp. 360-376 ◽  
Author(s):  
W. SATUŁA
Keyword(s):  
Density Functional ◽  
Nucleon Nucleon ◽  
High Energy ◽  
Low Energy ◽  
Fine Tuning ◽  
Local Theory ◽  
Energy Density Functional ◽  
Practical Applications ◽  
Nucleon Nucleon Interaction ◽  
Nuclear Shell

Low-energy nuclear structure is not sensitive enough to resolve the fine details of the nucleon-nucleon (NN) interaction. The insensitivity of the low-energy (infrared) physics to the details of the short-range strong interaction allows for a consistent, free of high-energy (ultraviolet) divergences, formulation of a local theory at the level of the local energy density functional (LEDF) including on the same footing, particle-hole and particle-particle channels. A major difficulty is related to the parameterization of the nuclear LEDF and its density dependence. It is argued that the structural simplicity of terminating or isomeric states offers an invaluable source of information that can be used for fine-tuning of the NN interaction in general and the nuclear LEDF parameters in particular. Practical applications of terminating states at the level of LEDF and nuclear shell-model are discussed.

scholarly journals The effective potential in nonconformal gauge theories

2017 ◽  
Vol 32 (02n03) ◽  
pp. 1750003 ◽  
Author(s):  
F. T. Brandt ◽  
F. A. Chishtie ◽  
D. G. C. McKeon
Keyword(s):  
Effective Potential ◽  
Vacuum Expectation ◽  
Vacuum Expectation Value ◽  
Mass Term ◽  
Coupling Constants ◽  
Tree Level ◽  
Massless Scalar ◽  
Classical Action ◽  
Expectation Value ◽  
Logarithmic Corrections

By using the renormalization group (RG) equation it has proved possible to sum logarithmic corrections to quantities that arise due to quantum effects in field theories. In particular, the effective potential [Formula: see text] in the Standard Model in the limit that there are no massive parameters in the classical action (the “conformal limit”) has been subject to this analysis, as has the effective potential in a scalar theory with a quartic self-coupling and in massless scalar electrodynamics. Having multiple coupling constants and/or mass parameters in the initial action complicates this analysis, as then several mass scales arise. We show how to address this problem by considering the effective potential in a Yukawa model when the scalar field has a tree-level mass term. In addition to summing logarithmic corrections by using the RG equation, we also consider the consequences of the condition [Formula: see text] where [Formula: see text] is the vacuum expectation value of the scalar. If [Formula: see text] is expanded in powers of logarithms that arise, then it proves possible to show that either [Formula: see text] is zero or that [Formula: see text] is independent of the scalar. (That is, either there is no spontaneous symmetry breaking or the vacuum expectation value is not determined by minimizing [Formula: see text] as [Formula: see text] is “flat”.)

scholarly journals On periodic solutions associated with the nonlinear feedback loop in the non-dissipative Lorenz model

2016 ◽  
Author(s):  
B.-W. Shen
Keyword(s):  
Critical Point ◽  
Critical Points ◽  
Homoclinic Orbit ◽  
Feedback Loop ◽  
The Other ◽  
Nonlinear Feedback ◽  
Restoring Force ◽  
Oscillatory Solutions ◽  
Energy Cycle ◽  
Large Cycle

Abstract. In this study, we discuss the role of the linear heating term and nonlinear terms associated with a nonlinear feedback loop in the energy cycle of the three-dimensional (X–Y–Z) non-dissipative Lorenz model (3D-NLM), where (X, Y, Z) represent the solutions in the phase space. Using trigonometric functions, we first present the closed-form solution of the nonlinear equation d2X/dτ2 + (X2/2)X = 0 without the heating term (i.e., rX), (where τ is a non-dimensional time and r is the normalized Rayleigh number), a solution that has not been previously documented. Since the solution of the simplified 3D-NLM is oscillatory (wave-like) and since the nonlinear term (X3) is associated with the nonlinear feedback loop, here, we suggest that the nonlinear feedback loop may act as a restoring force. When the heating term is considered, the system yields three critical points. A linear analysis suggests that the origin (i.e., the trivial critical point) is a saddle point and that the other two non-trivial critical points are stable. Here, we provide an analysis for three types of solutions that are associated with these critical points. Two of the solutions represent closed curves that travel around one non-trivial critical point or all three critical points. The third type of solution, appearing to connect the stable and unstable manifolds of the saddle point, is called the homoclinic orbit. Using the solution that contains one non-trivial critical point, here, we show that the competing impact of the nonlinear restoring force and the linear (heating) force determines the partitions of the averaged available potential energy from the Y and Z modes. Based on the energy analysis, an energy cycle with four different regimes is identified. The cycle is only half of a "large" cycle, displaying the wing pattern of a glasswinged butterfly. The other half cycle is antisymmetric with respect to the origin. The two types of oscillatory solutions with either a small cycle or a large cycle are orbitally stable. As compared to the oscillatory solutions, the homoclinic orbit is not periodic because it "takes forever" to reach the origin. Two trajectories with starting points near the homoclinic orbit may be diverged because one moves with a small cycle and the other moves with a large cycle. Therefore, the homoclinic orbit is not orbitally stable. In a future study, dissipation and/or additional nonlinear terms will be included in order to determine how their interactions with the original nonlinear feedback loop and the heating term may change the periodic orbits (as well as homoclinic orbits) to become quasi-periodic orbits and chaotic solutions.

On ground test of AL6016 structure influenced from space proton irradiated by MC-50 cyclotron

2018 ◽  
Vol 32 (19) ◽  
pp. 1840072
Author(s):  
Yong Hong Kim ◽  
Dae Weon Kim ◽  
Dong Chul Shin ◽  
Tae Gyu Kim ◽  
Yong Bae Kim
Keyword(s):  
Tensile Strength ◽  
Aluminum Alloy ◽  
Elastic Modulus ◽  
Kinetic Energy ◽  
High Energy ◽  
Low Energy ◽  
The Other ◽  
Thick Wall ◽  
Ground Test ◽  
Alloy 6061

Aluminum alloy 6061 is widely used for space development since the advent of space era irradiated with protons using cyclotron. In the condition of confined 5-mm thick wall, protons of 5 MeV, the case of low energy showed larger damage in the structure of aluminum alloy than those of 25.4 MeV, the case of high energy. Protons of 5 MeV stopped and transferred all kinetic energy into the 5-mm thick wall, on the other hand, protons of 25.4 MeV were penetrating and a few energy transferred. Elastic modulus reduced, but elongation was increased, finally tensile strength obviously showed that longer duration of exposure yielded weaker strength of material.

Low energy vs. high energy depositional settings and related sedimentary bodies in early Senenian rudist bearing carbonate shelves (central-southern Italy)

2001 ◽  
Vol 28 (1) ◽  
pp. 37-40 ◽  
Author(s):  
Gabriele Carannante ◽  
A. Laviano ◽  
D. Ruberti ◽  
Lucia Simone ◽  
G. Sirna ◽  
...  
Keyword(s):  
Southern Italy ◽  
High Energy ◽  
Low Energy ◽  
Depositional Settings

The Electron Effect of Aromatic Group: Control Conformation of 2-Aromatic Cyclododecanone Derivatives

2020 ◽  
Vol 24 (10) ◽  
pp. 1139-1147
Author(s):  
Yang Mingyan ◽  
Wang Daoquan ◽  
Wang Mingan
Keyword(s):  
1H Nmr ◽  
13C Nmr ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
The Other ◽  
Repulsive Interaction ◽  
X Ray Diffraction ◽  
X Ray ◽  
Electron Effect ◽  
Group Control

2-Phenylcyclododecanone and 2-cyclohexylcyclododecanone derivatives were synthesized and characterized by 1H NMR, 13C NMR, HR-ESI-MS and X-ray diffraction. Their preferred conformations were analyzed by the coupling constants in the 1H NMR spectra and X-ray diffraction, which showed the skeleton ring of these derivatives containing [3333]-2-one conformation, and the phenyl groups were located at the side-exo position of [3333]-2-one conformation due to the strong π-π repulsive interaction between the π- electron of benzene ring and π-electron of carbonyl group. The cyclohexyl groups were located at the corner-syn or the side-exo position of [3333]-2-one conformation depending on the hindrance of the other substituted groups. The π-π electron effect played a crucial role in efficiently controlling the preferred conformation of 2-aromatic cyclododecanone and the other 2-aromatic macrocyclic derivatives with the similar preferred square and rectangular conformations.

Sign in / Sign up

Export Citation Format

Share Document