6,735 research outputs found
On the Predictiveness of Single-Field Inflationary Models
We re-examine the predictiveness of single-field inflationary models and
discuss how an unknown UV completion can complicate determining inflationary
model parameters from observations, even from precision measurements. Besides
the usual naturalness issues associated with having a shallow inflationary
potential, we describe another issue for inflation, namely, unknown UV physics
modifies the running of Standard Model (SM) parameters and thereby introduces
uncertainty into the potential inflationary predictions. We illustrate this
point using the minimal Higgs Inflationary scenario, which is arguably the most
predictive single-field model on the market, because its predictions for ,
and are made using only one new free parameter beyond those measured
in particle physics experiments, and run up to the inflationary regime. We find
that this issue can already have observable effects. At the same time, this
UV-parameter dependence in the Renormalization Group allows Higgs Inflation to
occur (in principle) for a slightly larger range of Higgs masses. We comment on
the origin of the various UV scales that arise at large field values for the SM
Higgs, clarifying cut off scale arguments by further developing the formalism
of a non-linear realization of in curved space. We
discuss the interesting fact that, outside of Higgs Inflation, the effect of a
non-minimal coupling to gravity, even in the SM, results in a non-linear EFT
for the Higgs sector. Finally, we briefly comment on post BICEP2 attempts to
modify the Higgs Inflation scenario.Comment: 31 pp, 4 figures v4: Minor correction to section 3.1. Main arguments
and conclusions unchange
Inflating in a Trough: Single-Field Effective Theory from Multiple-Field Curved Valleys
We examine the motion of light fields near the bottom of a potential valley
in a multi-dimensional field space. In the case of two fields we identify three
general scales, all of which must be large in order to justify an effective
low-energy approximation involving only the light field, . (Typically
only one of these -- the mass of the heavy field transverse to the trough -- is
used in the literature when justifying the truncation of heavy fields.) We
explicitly compute the resulting effective field theory, which has the form of
a model, with , as a function of these
scales. This gives the leading ways each scale contributes to any low-energy
dynamics, including (but not restricted to) those relevant for cosmology. We
check our results with the special case of a homogeneous roll near the valley
floor, placing into a broader context recent cosmological calculations that
show how the truncation approximation can fail. By casting our results
covariantly in field space, we provide a geometrical criterion for
model-builders to decide whether or not the single-field and/or the truncation
approximation is justified, identify its leading deviations, and to efficiently
extract cosmological predictions.Comment: 28 pages + 3 appendices, references added and typos corrected,
matches published versio
Damping of gravitational waves by matter
We develop a unified description, via the Boltzmann equation, of damping of
gravitational waves by matter, incorporating collisions. We identify two
physically distinct damping mechanisms -- collisional and Landau damping. We
first consider damping in flat spacetime, and then generalize the results to
allow for cosmological expansion. In the first regime, maximal collisional
damping of a gravitational wave, independent of the details of the collisions
in the matter is, as we show, significant only when its wavelength is
comparable to the size of the horizon. Thus damping by intergalactic or
interstellar matter for all but primordial gravitational radiation can be
neglected. Although collisions in matter lead to a shear viscosity, they also
act to erase anisotropic stresses, thus suppressing the damping of
gravitational waves. Damping of primordial gravitational waves remains
possible. We generalize Weinberg's calculation of gravitational wave damping,
now including collisions and particles of finite mass, and interpret the
collisionless limit in terms of Landau damping. While Landau damping of
gravitational waves cannot occur in flat spacetime, the expansion of the
universe allows such damping by spreading the frequency of a gravitational wave
of given wavevector.Comment: 9 pages (10 pages in journal), published versio
Response of Two Sunflower (Helianthus Annuus L.) Genotypes to Va-mycorrhizal Inoculation and Phosphorus Levels
The performance of two sunflower genotypes (Morden and MSFH-8) with and without VA-mycorrhizal fungi at three P levels (38, 56 and 75 kg P2O5 ha-1) in vertisol of Dharwad was studied to determine the effect of mycorrhizal inoculation on plant growth, yield and P uptake. The results showed that the VAM inoculation increased sunflower yield (14%), total biomass (16%), oil content (3.1%) and P uptake (30.5%) over uninoculated control. The percent root colonization and chlamydo-spore count decreased with increasing P levels. The total biomass production, seed yield and P uptake of mycorrhizal plants at 38 kg P2O5 ha-1 more than the non-mycorrhizal plants at 75 kg P2O5 ha-1. The biomass and seed yield of mycorrhizal plants at same P level were more than the non-mycorrhizal plants. Mycorrhizal plants of Morden at 38 kg P2O5 ha-1 and MSFH-8 at 56 kg P2O5 ha-1 produced higher seed yield, oil content and total biomass than non-mycorrhizal plants supplied with 75 kg P2O5 ha-1. The results indicated that, VA-mycorrhizal inoculation helps in saving 25 and 50 percent of recommended dose of phosphatic fertilizer (75 kg P2O5 ha-1) in MSFH-8 (single cross hybrid) and Morden (open pollinated variety), respectively
Solving Hard AI Problem using CaRP as Online Network Security
Today, there is cut throat competition in Network Security and is major issue in Computer world also several security parameters are based on hard mathematical problems are available to tackle this problem. So many researchers trying to solve this problem from last decades. Using hard AI problems for security is up-and-coming as an exciting new concept so we have to show keen interest in this domain. Hence, in this paper, we are introducing better security parameters based on hard AI problems, explicitly, a novel family of graphical password systems built on top of Captcha technology, which we are proposing Captcha and Graphical Passwords (CaRP). CaRP is both a Captcha and a graphical password system. CaRP sort some security problems, such as online guessing attacks, relay attacks and shoulder-surfing attacks. Especially, a CaRP password can be establish only probabilistically by automatic online guessing attacks even if the password is in the search position. CaRP also offers a novel approach to address the well-known image hotspot problem in popular graphical password systems, such as PassPoints that often leads to less password choices. CaRP is not a universal solution but it offers reasonable security and usability and it may use few practical applications for getting better online security such as banking, railway reservation etc.
DOI: 10.17762/ijritcc2321-8169.15033
Review of code blue system and audit
Background: Code Blue systems are communication systems that ensure the most rapid and effective resuscitation of a patient in respiratory or cardiac arrest. Code blue was established in Bharati Hospital and Research Centre in Sept 2011 in order to reduce morbidity and mortality in wards. The aim of the study was to evaluate the current code blue system and suggest possible interventions to strengthen the system.Methods: It was retrospective observational descriptive study. The study population included all consecutive patients above the age of 18 years for whom code blue had been activated. Data was collected using code blue audit forms. The data was analysed using SPSS (Statistical Package for social sciences) software.Results: A total of 260 calls were made using the blue code system between September 2011 to December 2012. The most common place for blue code activation was casualty. The wards were next, followed by dialysis unit and OPD. The indications for code blue team activation were cardio-respiratory arrest (CRA) (88 patients, 33.84%), change in mental status (52 patients, 20%), road traffic accidents RTA (21, 8.07%), convulsions (29 patients 11.15%), chest pain (19 patients, 8.46%), breathlessness (18 patients,6.92%) and worry of staff about the patient (17 patients, 6.53%), presyncope (10 patients, 3.84%), and others (6 patients, 2.30%). The average response time was 1.58±0.96 minutes in our study. Survival rate was more in medical emergency group 46.15% than in CRA group 31.61%. Initial success rate was 35.2% and a final success rate was 34.6%.Conclusions: Establishment of code blue team in the hospital enabled us to provide timely resuscitation for patients who had “out of ICU” CRA. Further study is needed to establish the overall effectiveness and the optimal implementation of code blue teams. The increasing use of an existing service to review patients meeting blue code criteria requires repeated education and a periodic assessment of site-specific obstacles to utilization
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