scholarly journals Global monopole as a generator of a bulk-brane structure in Brans–Dicke bulk gravity

2020 ◽  
Vol 80 (11) ◽  
Author(s):  
Thiago R. P. Caramês ◽  
J. M. Hoff da Silva

AbstractWe investigate a braneworld model generated by a global monopole in the context of Brans–Dicke gravity. After solving the dynamical equations we found a model capable to alleviate the so-called hierarchy problem. The obtained framework is described by a hybrid compactification scheme endowed with a seven-dimensional spacetime, in which the brane has four non-compact dimensions and two curled extra dimensions. The relevant aspects of the resulting model are studied and the requirements to avoid the well known seesaw-like behavior are discussed. We show that under certain conditions it is possible to circumvent such a pathological behavior that characterizes most of the models that exhibit hybrid compactification. Lastly, we deepen our analysis by considering possible extensions of this model to a setup with multiple branes and orbifold-like extra dimension. For this, we compute the consistency conditions to be obeyed by this more general configuration as predicted by the braneworld sum rules formalism. This study indicates the possibility of exclusively positive brane tensions in the model.

2002 ◽  
Vol 17 (24) ◽  
pp. 1551-1558 ◽  
Author(s):  
YOSUKE UEHARA

We present a mini-review of the present constraints of the large extra dimension scenario. We show many experiments and considerations that can constrain the fundamental scale of the large extra dimension. We observe that constraints come from collider experiments are much weaker than those of astrophysical and cosmological considerations. When the number of extra dimension n is smaller than four, the constraint is so strong that the large extra dimension scenario cannot solve hierarchy problem. But when n ≥ 4 there is still possibility that it can solve the hierarchy problem.


2021 ◽  
Vol 2021 (4) ◽  
Author(s):  
A. de Giorgi ◽  
S. Vogl

Abstract The Kaluza-Klein (KK) decomposition of higher-dimensional gravity gives rise to a tower of KK-gravitons in the effective four-dimensional (4D) theory. Such massive spin-2 fields are known to be connected with unitarity issues and easily lead to a breakdown of the effective theory well below the naive scale of the interaction. However, the breakdown of the effective 4D theory is expected to be controlled by the parameters of the 5D theory. Working in a simplified Randall-Sundrum model we study the matrix elements for matter annihilations into massive gravitons. We find that truncating the KK-tower leads to an early breakdown of perturbative unitarity. However, by considering the full tower we obtain a set of sum rules for the couplings between the different KK-fields that restore unitarity up to the scale of the 5D theory. We prove analytically that these are fulfilled in the model under consideration and present numerical tests of their convergence. This work complements earlier studies that focused on graviton self-interactions and yields additional sum rules that are required if matter fields are incorporated into warped extra-dimensions.


2005 ◽  
Vol 20 (24) ◽  
pp. 1845-1857 ◽  
Author(s):  
E. O. ILTAN

We study [Formula: see text], i = e, μ, τ decays in the two-Higgs doublet model, with the inclusion of one and two spatial non-universal extra dimensions. We observe that the branching ratio is sensitive to two extra dimensions in contrary to a single extra dimension.


Open Physics ◽  
2019 ◽  
Vol 17 (1) ◽  
pp. 831-838
Author(s):  
Massimo Fioranelli ◽  
Alireza Sepehri ◽  
Maria Grazia Roccia ◽  
Mahdieh Ghasemi

Abstract Recently, a method for calculating the quantum spectrum of black holes has been proposed. We show that this method can be applied for radiations of 4 + n - dimensional water around a DNA. In this model, DNA acts like a black hole and produces a curved space-time in a water around it. In these conditions, molecules of water in four dimensional universe are entangled with some DNA-like structures in extra dimension. Consequently, the effects of structures of water in extra dimensions can be observed in four dimensions. The entangled structures emit some quantum spectrum which can be transmitted to pure waters. These waves produce a curved space-time in pure water and make an entanglement between structure of water on four and DNA-like structures in extra dimensions. As a result, some signatures of DNAs can be observed in pure water. This model helps us to understand the reason for the emergence of life on the earth. To explain the model better, we unify Darwin’s theory with string theory in a new Darwinian’s string theory. In this theory, a zero dimensional manifold decays into two types of closed strings. One type decays into open strings and then these strings join to each other and form cosmos. Another type decays into open strings which form biological matters like DNAs and molecules of water in universe and anti-DNAs and anti-water in anti-universe. Thus, DNAs and molecules water are connected to each other and anti-DNAs and molecules of anti-water in anti-universe through some closed strings. These strings helps to molecules of water to store their informations in extra dimension and have long time memory. Because, information that are transformed into extra dimensions through closed strings, could be returned into universe. Also, these closed strings could have the main role in DNA transduction. Because, they connect two tubes one including water and DNA and another pure water in universe to two tubes including anti-DNA and water in anti-universe and transform properties of DNA into pure water. As a result, Darwinian string theory can confirm both water memory and DNA transduction. Finally, this theory response to this question that why memory of water couldnt remain for a long time. In this model, open strings which connects atoms in universe with anti-atoms in anti-universe interact with open strings which connects molecules of water and anti-water and decrease their entanglement. This causes that exchanging information between water and anti-water decreases and memory is dis-appeared.


2005 ◽  
Vol 14 (12) ◽  
pp. 2347-2353 ◽  
Author(s):  
CHRIS CLARKSON ◽  
ROY MAARTENS

If string theory is correct, then our observable universe may be a three-dimensional "brane" embedded in a higher-dimensional spacetime. This theoretical scenario should be tested via the state-of-the-art in gravitational experiments — the current and upcoming gravity-wave detectors. Indeed, the existence of extra dimensions leads to oscillations that leave a spectroscopic signature in the gravity-wave signal from black holes. The detectors that have been designed to confirm Einstein's prediction of gravity waves, can in principle also provide tests and constraints on string theory.


2015 ◽  
Vol 12 (10) ◽  
pp. 1550102 ◽  
Author(s):  
Subhash Rajpoot ◽  
Sergiu I. Vacaru

We study an effective Einstein–Finsler theory on tangent Lorentz bundle constructed as a "minimal" extension of general relativity. Black ring and Kerr-like ellipsoid exact solutions and solitonic configurations are presented. In this endeavor the relevant metric depends not only on four-dimensional spacetime coordinates and also on velocity type variables that can be interpreted as additional coordinates in the space of "extra dimensions".


2007 ◽  
Vol 16 (03) ◽  
pp. 841-851 ◽  
Author(s):  
THOMAS J. HUMANIC ◽  
BENJAMIN KOCH ◽  
HORST STÖCKER

The concept of Large Extra Dimensions (LED) provides a way of solving the Hierarchy Problem which concerns the weakness of gravity compared with the strong and electro-weak forces. A consequence of LED is that miniature Black Holes (mini-BHs) may be produced at the Large Hadron Collider in p + p collisions. The present work uses the CHARYBDIS mini-BH generator code to simulate the hadronic signal which might be expected in a mid-rapidity particle tracking detector from the decay of these exotic objects if indeed they are produced. An estimate is also given for Pb + Pb collisions.


2011 ◽  
Vol 2011 (1) ◽  
Author(s):  
Daniel R. Gulotta ◽  
Christopher P. Herzog ◽  
Matthias Kaminski
Keyword(s):  

2015 ◽  
Vol 30 (15) ◽  
pp. 1540010 ◽  
Author(s):  
Elena Accomando

We review the present bounds on Kaluza–Klein (KK)-excitations of Standard Model gauge bosons, predicted by TeV size extra dimensions, which have been set by the ElectroWeak Precision Test (EWPT) and recently by the direct searches performed at the CERN Large Hadron Collider (LHC). Concerning the theoretical framework we present results for the Non-Universal Extra Dimension (NUED) model with matter localized at the boundaries and all gauge bosons propagating into the bulk and acquiring KK-excitations. We also discuss its simplified version, NUED(EW), where only the ElectroWeak SM gauge bosons are allowed to propagate in the extra dimension, and its next-to-minimal version ElectroWeak Universal Extra Dimension (UED)(EW) where SU(3) is localized on the brane while the SU(2)×U(1) particle content fully propagates into the bulk.


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