arXiv subjects

Alireza Sepehri

Publications and source records attributed to Alireza Sepehri.

At least 19 recordsLinked to original sources

arXiv2025

Constructing the Padmanabhan Holographic Model in a BIonic System

Recently, Padmanabhan has argued that a difference between the number of degrees of freedom on the surface and the number in a bulk causes the expansion of the universe. We can reconsider this idea in a BIon system. A Bion is formed from two branes that are connected by a wormhole. Our universe may live on one of these branes. Each brane could be formed by joining lower-dimensional branes, such as $D_1$ ones. By joining $D_1$ branes, a $D_n$ brane is formed, and some amounts of energy are released. Then, perhaps some dimensions are compacted, and a certain amount of energy is released. These energies cause a significant difference between the number of degrees of freedom on the surface and in the bulk of branes. This causes the evolution of the universe and many changes in thermodynamic parameters, such as entropy, as well as cosmic parameters, including the Hubble constant. We obtain the standard form of the Hubble parameter and its dependency on redshift in a Bion system.

hep-th↗

arXiv2019

Tachyonic $δ$-Tsallis entropy of a thermal tachyonic BIon

When a brane and an anti-brane come close to each other, the tachyonic potential between them increases and a tachyon wormhole is formed. This configuration, which consists of two branes and a tachyonic wormhole, is called a thermal tachyonic BIon. By considering the thermodynamic behaviour of this system, one finds that its entropy has the same form as that of the Tsallis one. By decreasing the separation between the branes, the tachyonic potential increases, and the entropy grows.

hep-ph↗

arXiv2019

Expansion and contraction of accretion disks of a rotating thermal BIon in a Rindler space-time

In this paper, we consider the evolution of accretion disks of a rotating BIon in a Rindler space-time. This space-time emerges because of the acceleration of the disks in a BIon. A BIon is constructed from a pair of accretion disks that are connected by a wormhole. We will show that in a rotating BIon, by increasing the rotation velocity, the area of one accretion disk grows, while the area of the other shrinks. Also, we consider four types of accreion disks which are produced in a Rindler space-time.

gr-qc↗

arXiv2019

Emergence and expansion of cosmic space in an accelerating BIon

We generalize the Padmanabhan [arXiv:hep-th/1206.4916] mechanism to an accelerating BIon and show that the difference between the number of degrees of freedom on the boundary surface and the number of degrees of freedom in a bulk region causes the accelerated expansion of a BIon. We also consider the evolution of a universe which emerges on this BIon, and obtain its Hubble parameter and energy density.

gr-qc↗

arXiv2018

Tsallis $δ$-entropy in an accelerating BIon

In this research, we consider thermodynamically the behaviour of an accelerating BIon and show that the entropy of this system has the form of Tsallis entropy. A BIon is a system that consists of a brane, an anti-brane and a wormhole which connects them together. By increasing the acceleration of branes, the area of BIon increases and its Tsallis entropy grows.

hep-th↗

arXiv2018

A mathematical model for DNA

Recently, some authors have shown that a DNA molecule produces electromagnetic signals and communicates with other DNA molecules or other molecules. In fact, a DNA acts like a receiver or transmitter of radio waves. In this paper, we suggest a mathematical model for the DNA molecule and use of its communication to cure some diseases like cancer. In this model, first, by using concepts from string theory and M-theory, we calculate the energy of a DNA in terms of interactions between free electrons and bound electrons. We show that when a DNA is damaged, its energy changes and an extra current is produced. This extra current causes the electromagnetic signals of a damaged DNA molecule to be different when compared to the electromagnetic signals of a normal DNA molecule. The electromagnetic signals of a damaged DNA molecule induces an extra current in a normal DNA molecule and leads to its destruction. By sending crafted electromagnetic signals to normal DNA molecules and inducing an opposite current with respect to this extra current, we can prevent the destruction of normal DNA. Finally, we argue that the type of packing of DNA in chromosomes of men and women are different. This causes radiated waves from DNAs of men and women to have opposite signs and cancel the effect of each other in a pair. Using this property, we suggest another mechanism to cancel the effect of extra waves, which are produced by DNAs in cancer cells of a male or a female, by extra waves which are produced by DNAs in similar cells of a female or a male and prevent the progression of the disease.

physics.bio-ph↗

arXiv2018

MOG without anomaly

We obtain the action of Moffat's Modified Gravity, (MOG), a scalar-tensor-vector theory of gravitation, by generalizing the Horava-Witten mechanism to fourteen dimensions. We show that the resulting theory is anomaly-free. We propose an extended version of MOG that includes fermionic fields.

hep-th↗

arXiv2017

The BIonic diode in a system of trigonal manifolds

A BIonic diode is constructed of two polygonal manifolds connected by a Chern-Simons manifold. The shape and the angle between atoms of molecules on the boundary of two polygonal manifolds are completely different. For this reason, electrons on the Chern-Simons manifold are repelled by molecules at the boundary of one manifold and absorbed by molecules on the boundary of another manifold. The attractive and repulsive forces between electrons are carried by masive photons. For example, when two non-similar trigonal manifolds join to each other, one non-symmetrical hexagonal manifold is emerged and the exchanged photons form Chern-Simons fields which live on a Chern-Simons manifold in a BIon. While, for a hexagonal manifold, with similar trigonal manifolds, the photons exchanged between two trigonal manifolds cancel the effect of each other and BIonic energy becomes zero. Also, exchanging photons between heptagonal and pentagonal manifolds lead to the motion of electrons on the Chern-Simons manifold and formation of BIonic diode. The mass of photons depend on the shape of molecules on the boundary of manifolds and the length of BIon in a gap between two manifolds.

physics.gen-ph↗

arXiv2017

Quarkonium in a thermal BIon

In the present article, the authors intend to propose a new theory which potentially allows the propagation of the formation and the evolution of quarkonium in a thermal BIon. When quarks are close to each other, quarkonium behaves like a scalar and by their getting away, it transits to a fermionic system. In order to analyze this particular behaviour, a new outlook approach needs to be adopted as the concurrent view is found deficient to analyse the aforesaid behaviour. Therefore, the authors' post deliberation accept the fermions and fermionic being cognate. We need to accept a theory that the origin of fermions and bosons be the same. However, in $M$-theory, these particles are independent and for this reason, \textbf{we use a new broader theory based on Lie-$N$-Algebra and we call it BLNA (Broad Lie-$N$-Algebra)} theory. Thus, the BLNA in a way the $M$-theory with $11$ dimensions. In this model, two types of energies with opposite signs emerge from nothing such as the sum over them becomes zero. They produce two types of branes with opposite quantum numbers and bosonic fields, which interact with each other and get compact. By compacting branes, the quarks and anti-quarks are produced on branes and exchange the graviton and the gravitino. These particles produce two types of wormholes which act opposite to each other. They preclude from closing or getting away of branes from each other and also occurrence of confinement. This confined potential which emerges from these wormholes depends on the separation distance between quarks and anti-quarks and also on temperature of system and is reduced to predicted potential in experiments and QCD. Also, total entropy of this system grows with increasing temperature and produces a repulsive force which leads to the separation of quarks and anti-quarks and also to the emergence of deconfinement.

hep-th↗

arXiv2017

On the origin of generalized uncertainty principle from compactified M5-brane

In this paper, we demonstrate that compactification in M-theory can lead to a deformation of field theory consistent with the generalized uncertainty principle (GUP).We observe that the matter fields in the M3-brane action contain higher derivative terms. We demonstrate that such terms can also be constructed from a reformulation of the field theory by the GUP. In fact, we will construct the Heisenberg algebra consistent with this deformation, and explicitly demonstrate it to be the Heisenberg algebra obtained from the GUP. Thus, we use compactification in M-theory to motivate for the existence of the GUP.

gr-qc↗

arXiv2017

Birth of the GUP and its effect on the entropy of the Universe in Lie-$N$-algebra

In this paper, the origin of the generalized uncertainty principle (GUP) in an $M$-dimensional theory with Lie-$N$-algebra is considered. This theory which we name GLNA(Generalized Lie-$N$-Algebra)-theory can be reduced to $M$-theory with $M=11$ and $N=3$. In this theory, at the beginning, two energies with positive and negative signs are created from nothing and produce two types of branes with opposite quantum numbers and different numbers of timing dimensions. Coincidence with the birth of these branes, various derivatives of bosonic fields emerge in the action of the system which produce the $r$ GUP for bosons. These branes interact with each other, compact and various derivatives of spinor fields appear in the action of the system which leads to the creation of the GUP for fermions. The previous predicted entropy of branes in the GUP is corrected as due to the emergence of higher orders of derivatives and different number of timing dimensions.

physics.gen-ph↗

arXiv2017

Recovery of hadronic cross section inside the mini black holes at LHC

In curved space time inside the shell of TeV black holes, many gluons and quarks produce due to Unruh effect, interact with each other and create Higgs boson. Studying the Unruh effect, we show that the inside state of the black hole for gluons and quarks can be represented by a maximally entangled two mode squeezed state of inside and matter Hilbert spaces of black hole. Comparing the Higgs boson production outside and inside the shell, we observe that at lower mass, MBH<4 TeV, and at higher mass, MBH>9 TeV, the Higgs boson will not be produced outside the shell of black hole. However this particle can be produced inside the shell for 2.5 TeV 12.5 TeV the black hole can only emit massless gluons. However, inside the shell of black hole is able to produce a quark for 2.5 TeV<MBH<14 TeV. We also find that the micro black hole can be a source for Higgs production at LHC. Finally we calculate the effects of Higgs boson radiation due to inside the shell and outside the shell of mini black holes on hadronic cross section at LHC. We observe that as the order of perturbation theory increases, this effect becomes systematically more effective because at higher orders there exists more channels for Higgs production and their decay of Higgs into massive quark-anti quarks in our calculation. At smaller mass, MBH<2 TeV, the NNLO contribution is large while the cross sections at NLO and at LO are rising and respectively exhibit a turn-over at moderate values of black hole's mass.The peak moves from about 5 TeV to 2.5 TeV. It is concluded that the processes of hadronization inside the event horizon of mini black holes are affected the hadronic cross section outside the event horizon and can be observed at LHC.

hep-ph↗

arXiv2017

Current density and conductivity through modified gravity in the graphene with defects

We propose a model describing the evolution of the free electron current density in graphene. Based on the concept of Mp-branes, we perform the analysis using the difference between curvatures of parallel and antiparallel spins. In such a framework an effective graviton emerges in the form of gauge field exchange between electrons. In a plain graphene system, the curvatures produced by both kinds of spins neutralize each other. However, in the presence of defects, the inequality between curvatures leads to the emergence of current density, modified gravity and conductivity. Depending on the type of the defects, the resulting current density can be negative or positive.

gr-qc↗

arXiv2017

Holographic Cosmology from BIonic Solutions

In this paper, we will use a BIonic solution for analyzing the holographic cosmology. A BIonic solution is a configuration of a D3-brane and an anti-D3-brane connected by a wormhole, and holographic cosmology is a recent proposal to explain cosmic expansion by using the holographic principle. In our model, a BIonic configuration will be produced by the transition of fundamental black strings. The formation of a BIonic configuration will cause inflation. As the D3-brane moves away from the anti-D3-brane, The wormhole will get annihilated, and the inflation will end with the annihilation of this wormhole. However, it is possible for a D3-brane to collide with an anti-D3-brane. Such a collision will occur if the distance between the D3-brane and the anti-D3-brane reduces, and this will create tachyonic states. We will demonstrate that these tachyonic states will lead to the formation of a new wormhole, and this will cause acceleration of the universe before such a collision.

gr-qc↗

arXiv2017

The origin of Chern-Simons modified gravity from an 11 + 3-dimensional manifold

In this contribution, it is our aim to show that the Chern-Simons terms of modified gravity can be understood as generated by the addition of a 3-dimensional algebraic manifold to an initial 11-dimensional space-time manifold; this builds up an 11+3-dimensional space-time. In this system, firstly, some fields living in the bulk join the fields that live on the 11-dimensional manifold, so that the rank of the gauge fields exceeds the dimension of the algebra; consequently, there emerges an anomaly. To solve this problem, another 11-dimensional manifold is included in the 11 +3-dimensional space-time, and it interacts with the initial manifold by exchanging Chern-Simons fields. This mechanism is able to remove the anomaly. Chern-Simons terms actually produce an extra manifold between the pair of 11-dimensional manifolds of the 11+3-space-time. Summing up over the topology of both the 11-dimensional manifolds and the topology of the exchanged Chern-Simons manifold in the bulk , we conclude that the total topology shrinks to one, which is in agreement with the main idea of the Big Bang theory.

hep-th↗

arXiv2017

The birth of the universe in a new G-Theory approach

Recently, Padmanabhan has discussed that the expansion of the cosmic space is due to the difference between the number of degrees of freedom on the boundary surface and the number of degrees of freedom in a bulk region. Now, a natural question arises that how these degrees of freedom are emerged from nothing? We try to address this issue in a new theory which is more complete than M-theory and reduces to it with some limitations. In M-theory, there isn't any stable object like stable M3-branes that our universe is formed on it and for this reason can't help us to explain cosmological events. In this research, we propose a new theory, named G -theory which could be the mother of M-theory and superstring theory. In G-theory, at the beginning, two types of G0-branes, one with positive energy and one with negative energy are produced from nothing in fourteen dimensions. Then, these branes are compactified on three circles via two different ways (symmetrically and anti-symmetrically), and two bosonic and fermionic parts of action for M0-branes are produced. By joining M0-branes, supersymmetric Mp-branes are created which contain the equal number of degrees of freedom for fermions and bosons. Our universe is constructed on one of Mp-branes and other Mp-brane and extra energy play the role of bulk. By dissolving extra energy which is produced by compacting actions of Gp-branes, into our universe, the number of degrees of freedom on it and also it's scale factor increase and universe expands. We test G-theory with observations and find that the the magnitude of the slow-roll parameters and the tensor-to-scalar ratio in this model are very smaller than one which are in agreement with predictions of experimental data. Finally, we consider the origin of the extended theories of gravity in G-theory and show that these theories could be anomaly free.

physics.gen-ph↗

arXiv2016

Emergence of the world with Lie-N-algebra and M-dimensions from nothing

In this paper, we propose a new model in Lie-N-algebra that removes big bang singularity and produces the world with all it's objects and dimensions from nothing. We name this theory as G-theory. In this model, first, two types of energies with opposite signs are produced from nothing such as the sum over them be zero. They create two types of branes with opposite quantum numbers which interact with each other by exchanging bosonic tensor fields like graviton and compact. By compacting branes, fermionic tensor fields are emerged which some of them play the role of the gravitinos. Also, some dimensions take extra (i) factors, their properties become different and they behave like time dimensions. Gravitons and gravitinos create two types of wormholes which lead to the oscillation of branes between expansion and contracting branches. These wormholes produce a repulsive gravity in compacted branes and cause that their particles get away from each other and expansion branch begin. Also, they create an attractive gravity in opening branes and lead to closing their particles and starting the contraction epoch. Our universe is born on one of these branes and oscillates between contraction and expansion branch.

physics.gen-ph↗

arXiv2016

Role of higher -dimensional evolving wormholes in the formation of a big rip singularity

We study the evolutions of 4D universe on the M2-M5 BIon in the thermal background. The BIon consists of a D-brane and a parallel anti-D-brane which a wormhole connects them. When the branes and antibranes are far from each other and the brane's spike and the antibrane's spike are well separated, the wormhole cannot be built. However, when the branes and anti-branes are close to each other, a wormhole can be formed between them. Under this condition, there are many ways for flowing energy from transverse dimensions into our universe. This energy overcomes all other forms of energy, such as the gravitational repulsion and causes that our epoch is terminated at a Big-Rip singularity. We show that at this point, universe would be disappeared and one black M2-brane is formed. Finally, we examine our model against WMAP, Planck and BICEP2 experiments and get the ripping time. Comparing the model with experimental data, we obtain $N\simeq 50$ and $n_{s}\simeq 0.96$, where \emph{N} and $n_{s}$ are the number e-folds and the spectral index respectively. These results could be located in $0.01 < R_{Tensor-scalar} < 0.3$, where $R_{Tensor-scalar}$ is the tensor-scalar ratio. In this epoch, the Big Rip singularity happens in a finite time $t_{rip}=31(Gyr)$ for WMAP and Planck experimnts and $t_{rip}=28(Gyr)$ for BICEP2 experiment. By comparing this time with the time of the Big Rip in brane-antibrane, we observe that the wormhole in BIonic system causes that the destruction of the universe becomes faster.

gr-qc↗