Hidden Spin-3/2 Field in the Standard Model

Here we show that a massive spin-3/2 field can hide in the SM spectrum in a way revealing itself only virtually. We study collider signatures and loop effects of this field, and determine its role in Higgs inflation and its potential as Dark Matter. We show that this spin-3/2 field has a rich linear collider phenomenology and motivates consideration of a neutrino-Higgs collider. We also show that study of Higgs inflation, dark matter and dark energy can reveal more about the neutrino and dark sector.Comment: 8 pages, 8 figures, accepted for publication in Eur. Phys. J.

Fine-Tuned Spin-3/2 and the Hierarchy Problem

In the past, Kundu et al. and Chakraborty et al. used extra scalar fields to cancel the quadratic divergences in the Higgs mass squared and they determined the mass of the required scalar field. In this work, a spin-3/2 particle has been used in the same manner to nullify the power-law divergences, and it is determined that the mass of the spin-3/2 particle resides in the ball park of the GUT scale

Polimer kuantizasyonunda tünelleme ve kauntum zeno etkisi

Thesis (Master)--Izmir Institute of Technology, Physics, Izmir, 2014Includes bibliographical references (leaves 47-51)Text in English; Abstract: Turkish and Englishviii, 57 leavesPolymer quantization is a non-standard and exotic representation of the canonical commutation relations which is introduced in the context of loop quantum gravity to investigate the low energy limit of this non-perturbative quantization of gravity. It is one of the representations of the Weyl-Heisenberg algebra which is inequivalent to the standard Schr¨odinger representation. Since this representation is inequivalent to Schr¨odinger mechanics, by Stone-von Neuman uniqueness theorem there should not be a one to one correspondence between the operators of the two representations. It turns out that, one can not define the position and momentum operators simultaneously in this construction. In this work, we use the standard position operator and a second operator which is the analog of ^p. To define an operator similar to the momentum operator ^p, one needs to use a regularization length scale which can not be removed and stays as a free parameter in the theory. This free parameter is interpreted to descend from the fundamental discreteness of space in loop quantum gravity. As another application of the polymer quantization scheme, in this work we investigate the one dimensional quantum mechanical tunneling phenomenon from the perspective of polymer representation of a non-relativistic point particle, derive the transmission and reflection coefficients and show that they add up to one which is the requirement of probability conservation. Since any tunneling phenomenon inevitably evokes a tunneling time we attempt an analytical calculation of tunneling times by defining an operator well suited in discrete spatial geometry. We expand our time expression in a Maclaurin series around zero polymer length scale and arrive at results which hint at appearance of the Quantum Zeno Effect in polymer framework. Quantum Zeno effect is the inhibition of a quantum system from making a transition from an initial state to a final state. And in summary, as a result of our work we can say that discretization of space leads to the Quantum Zeno effect

Type-3/2 Seesaw Mechanism

Type-I seesaw provides a natural explanation for the tiny neutrino masses. The right-handed neutrino masses it requires are, however, too large to keep the Higgs boson mass at its measured value. Here we show that vector-spinors, singlet leptons like the right-handed neutrinos, generate the tiny neutrino masses naturally by the exchange of its spin-1/2 and spin-3/2 components. This one-step seesaw mechanism, which we call Type-3/2 seesaw, keeps the Higgs boson mass unchanged at one loop, and gives cause therefore to no fine-tuning problem. If the on-shell vector-spinor is a pure spin-3/2 particle then it becomes a potential candidate for hidden dark matter diluting due only to the expansion of the Universe. The Type-3/2 seesaw provides a natural framework for the neutrino, Higgs boson and dark matter sectors, with overall agreement with current experiments and observations.Comment: v3: 5 pages, 4 figs, 1 table; emphasized vector-spinor, no change in the results and conclusio

Violation of the holographic principle in the loop quantum gravity

In this paper, we analyze the holographic principle using loop quantum gravity (LQG). This will be done by using polymeric quantization for analysing Yurtsever's holographic bound on the entropy, which is obtained from local quantum field theories. As the polymeric quantization is the characteristic feature of loop quantum gravity, we will argue that this calculation will indicate the effect of loop quantum gravity on the holographic principle. Thus, we will be able to explicitly demonstrate the violation of the holographic principle in the loop quantum gravity

Inflation in symmergent metric-Palatini gravity

In this paper, we study the cosmological inflation phenomenon in symmergent gravity theory. Symmergent gravity is a novel framework which merges gravity and the standard model (SM) so that the gravity emerges from the matter loops and restores the broken gauge symmetries along the way. Symmergent gravity is capable of inducing the gravitational constant G and the quadratic curvature coefficient cO from the loop corrections of the matter sector in a flat space-time. In the event that all the matter fields, including the beyond the standard model (BSM) sector, are mass degenerate, the vacuum energy can be expressed in terms of G and cO . The parameter which measures the deviation from the mass degeneracy is dubbed α̂. The parameters, cO and α̂, of symmergent gravity convey the information about the fermion and boson balance in the matter (SM+BSM) sector in number and in mass, respectively. In our analysis, we have investigated the space of the symmergent parameters cO and α̂ wherein they produce results that comply with the inflationary observables ns , r, and dns /d ln k. We have shown that the vacuum energy together with the quadratic curvature term arising in the symmergent gravity prescription are capable of inflating the universe provided that the quadratic curvature coefficient cO is negative (which corresponds to fermion dominance in number in the matter sector) and the deviation from the mass degeneracy in the matter sector is minute for both boson mass dominance and fermion mass dominance cases

Dimensional regularization in quantum field theory with ultraviolet cutoff

In view of various field-theoretic reasons, in the present work, we study the question of if the usual dimensional regularization can be extended to quantum field theories with an ultraviolet cutoff (Poincare-breaking scale) in a way that preserves all the properties of the dimensional regularization. And we find that it can indeed be achieved. The resulting extension gives a framework in which the power-law and logarithmic divergences get detached to involve different scales. This new regularization scheme, the detached regularization as we call it, enables one to treat the power-law and logarithmic divergences differently and independently. We apply the detached regularization to the computation of the vacuum energy and to two well-known quantum field theories, namely the scalar and spinor electrodynamics. As a case study, we consider Fujikawa's subtractive renormalization in the framework of the detached regularization, and show its effectiveness up to two loops by specializing to scalar self energy. We discuss various application areas of the detached regularization

Clinical characteristics, disease activity, functional status, and quality of life results of patients with psoriatic arthritis using biological and conventional synthetic disease-modifying antirheumatic drugs

Objectives: This study aims to compare the clinical characteristics, disease activity, and quality of life (QoL) of patients with psoriatic arthritis (PsA) who use biological and conventional synthetic disease-modifying antirheumatic drugs (DMARDs) in a nationwide cohort throughout Turkey. Patients and methods: A total of 961 patients (346 males, 615 females; mean age: 46.9±12.2 years; range, 18 to 81 years) with PsA according to the classification criteria for PsA were included in the study. The patients’ demographic and clinical characteristics, physical examination results, Disease Activity Score 28, Disease Activity Index for Psoriatic Arthritis and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Psoriasis Area and Severity Index, Bath Ankylosing Spondylitis Functional Index, Bath Ankylosing Spondylitis Metrology Index, Hospital Anxiety and Depression Scale, Health Assessment Questionnaire, Psoriatic Arthritis Quality of Life (PsAQoL), and Short Form-36 scores were all recorded. Results: Of the patients, 23% underwent biological DMARD (bDMARD) monotherapy, 42% underwent conventional synthetic DMARD (csDMARD) monotherapy, 10% underwent a csDMARD combination therapy, and 10% underwent a combination bDMARD and csDMARD treatment. The Visual Analog Scale (VAS pain), patient global assessment, physician global assessment, and BASDAI scores were found to be lower among patients using combination treatment of csDMARD and bDMARD, while the swollen joint count was found to be lower among patients using bDMARD. The PsAQoL score was found to be the lowest among patients not using any medication and the highest among those using bDMARD. Conclusion: In our study, patients with PsA were successfully treated with both csDMARD and bDMARD monotherapy. When the biological treatments used for PsA were compared with csDMARD, it was found that biological treatments had a positive effect on both disease activity and the QoL. Combinations of csDMARDs and bDMARDs were preferred in cases in which the disease activity was still high or increased. Because of the highest efficacy of the combined treatment, we highly suggest increasing the number of patients on combined treatment

The impact of fatigue on patients with psoriatic arthritis: A multi-center study of the TLAR-network

Fatigue is a substantial problem in patients with psoriatic arthritis (PsA) that needs to be considered in the core set of domains. This study aimed to evaluate fatigue and its relationship with disease parameters, functional disability, anxiety, depression, quality of life, and correlation with disease activity as determined by various scales. A total of 1028 patients (677 females, 351 males) with PsA who met the CASPAR criteria were included [Turkish League Against Rheumatism (TLAR) Network multicenter study]. The demographic features and clinical conditions of the patients were recorded. Correlations between fatigue score and clinical parameters were evaluated using the Disease Activity Score 28 (DAS28), Disease Activity in Psoriatic Arthritis (DAPSA), Clinical DAPSA (cDAPSA), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), the Fibromyalgia Rapid Screening Tool (FiRST), minimal disease activity (MDA), and very low disease activity (VLDA). Fatigue was assessed with the Functional Assessment of Chronic Illness Therapy (FACIT-F) and a 10-point VAS (VAS-F). The mean age of the patients was 47 (SD: 12.2) years, and the mean disease duration was 6.4 (SD: 7.3) years. The mean VAS-F score was 5.1 (SD: 2.7), with fatigue being absent or mild, moderate, and severe in 12.8%, 24.6%, and 62.5% of the patients, respectively. Fatigue scores were significantly better in patients with DAS28 remission, DAPSA remission, cDAPSA remission, MDA, and VLDA (p < 0.001). Fatigue scores significantly increased with increasing disease activity levels on the DAS28, DAPSA, and cDAPSA (p < 0.001). VAS-F scores showed correlations with the scores of the BASDAI, BASFI, PsAQoL, HAD-A, FiRST, pain VAS, and PtGA. FiRST scores showed fibromyalgia in 255 (24.8%) patients. FACIT-F and VAS-F scores were significantly higher in patients with fibromyalgia (p < 0.001). In regression analysis, VLDA, BASDAI score, FiRST score, high education level, HAD-Anxiety, and BMI showed independent associations with fatigue. Our findings showed that fatigue was a common symptom in PsA and disease activity was the most substantial predictor, with fatigue being less in patients in remission, MDA, and VLDA. Other correlates of fatigue were female gender, educational level, anxiety, quality of life, function, pain, and fibromyalgia

Enthesitis and its relationship with disease activity, functional status, and quality of life in psoriatic arthritis: A multi-center study

Psoriatic arthritis (PsA) is an inflammatory arthritis with distinct phenotypic subtypes. Enthesitis is assigned as a hallmark of the disease, given its significant relations to disease activity and quality of life. Our objective is to evaluate the prevalence of enthesitis and its association with some clinical parameters, particularly quality of life, using data from a national registry. Patients with PsA meeting ClASsification criteria for Psoriatic Arthritis (CASPAR) were enrolled by means of a multi-centre Turkish League Against Rheumatism (TLAR) Network Project. The following information was recorded in web-based case report forms: demographic, clinical and radiographic data; physical examination findings, including tender and swollen joint counts (TJC and SJC); nail and skin involvement; Disease Activity Score-28 for Rheumatoid Arthritis with Erythrocyte Sedimentation Rate (DAS 28-ESR); Bath Ankylosing Spondylitis Disease Activity Index (BASDAI); Maastricht Ankylosing Spondylitis Enthesitis Score (MASES); Psoriasis Area Severity Index (PASI); Bath Ankylosing Spondylitis Radiology Index for the spine (BASRI-s); Health Assessment Questionnaire (HAQ); Bath Ankylosing Spondylitis Functional Index (BASFI); Health Assessment Questionnaire for the spondyloarthropathies (HAQ-s); Psoriatic arthritis quality of Life scale (PsAQoL); Short Form 36 (SF-36); Hospital Anxiety Depression Scale (HADS); Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F); and Fibromyalgia Rapid Screening Tool (FiRST) scores. The patients were divided into two groups, namely with and without enthesitis, based on the triple Likert-type physician-reported statement of ‘active enthesitis’, ‘history of enthesitis’ or ‘none’ in the case report forms. Patients with active enthesitis were compared to others in terms of these clinical parameters. A total of 1130 patients were enrolled in this observational study. Of these patients, 251 (22.2%) had active enthesitis according to the clinical assessment. TJC, HAQ-s, BASDAI, FiRST and PsAQoL were significantly higher whereas the SF-36 scores were lower in patients with enthesitis (p < 0.05). Chronic back pain, dactylitis, and tenosynovitis were more frequent in the enthesopathy group (59.4%/39%, 13.1%/6.5% and 24.7%/3.4%, respectively). Significant positive correlations between the MASES score and the TJC, HAQ, DAS 28-ESR, BASDAI, FiRST and PsAQoL scores, and a negative correlation with the SF-36 score were found. When linear regression analysis was performed, the SF-36 MCS and PCS scores decreased by − 9.740 and − 11.795 units, and the FiRST scores increased by 1.223 units in patients with enthesitis. Enthesitis is an important involvement of PsA with significant relations to quality of life determined with PsAQoL and SF-36 scores. Our study found higher frequency of dactylitis and chronic back pain, and worse quality of life determined with SF-36 and PsAQoL scores in patients with enthesitis