Gravitational domain walls and p-brane distributions

龙源期刊网
美国科学家的新理论：地心有个天然核反应堆
作者：半山
来源：《发明与创新(学生版)》2005年第12期
美国能源部橡树岭实验室科学家在美国地球物理联盟会议上提出，地心有个直径8公里、由铀和钚组成的天然核反应堆，这个巨大的反应堆是地球所有生命生存能源的来源。

提出这项理论的研究员汉顿说：“强有力的证据表明，在地心有个由铀和钚组成的快中子反应堆，这种反应堆可自行产生新的燃料。

”
这项理论完全推翻了现有地心组成的理论，引发极大的争议。

现有理论认为，地心是一团熔化的铁和镍等金属，其外面罩着熔化的地幔。

橡树岭实验室科学家则说，地心是一个天然核反应堆，这个核反应堆能产生磁力罩，保护地球不受太阳所发出各种粒子的轰击，火山爆发和大陆板块的移动都依赖其所提供的能量。

该项新的理论还认为，地球将于20亿年后因地心核反应堆燃料耗尽，磁力罩消失，而使地球上的生命结束，远比以前估计的40亿年要早。

橡树岭研究所的科学家是根据火山爆发所产生的辐射物质提出这个理论的，并为地心核反应堆的形成编出一个先进的计算机程序。

据称，这项理论主要的证据之一，是夏威夷和冰岛附近的海底所喷出的岩浆含有相当高的氦－3同位素，而这种同位素只可能在核裂变反应中产生。

汉顿及其同事认为，他们的理论可以解释其他科学家所不能解释的一些神秘现象，包括地球磁场如何产生等，一些理论认为地球磁场是由地心附近熔化的铁熔液所产生。

橡树岭实验所的科学家说，其他星球的核心也可能有这种核反应堆，这就可以解释为什么木星辐射出的能量比从太阳得到的能量多。

关于太空宇宙的英语作文三句或四句I. IntroductionThe universe, an immense expanse teeming with celestial wonders, has long captivated human imagination and driven our insatiable quest for knowledge. From the twinkling stars that adorn our night skies to the enigmatic black holes lurking in the darkness, the cosmos is a realm of unfathomable beauty and mystery. This vast, ever-expanding entity, comprised of billions of galaxies, each housing countless stars and their planetary systems, represents the ultimate frontier for scientific inquiry.II. The Observable Universe: A Glimpse into Infinity Our observable universe, extending approximately 93 billion light-years in diameter, is but a tiny fraction of what may lie beyond. It contains a staggering array of celestial bodies, ranging from blazing stars in various stages of life to the ethereal, ghostly remnants of exploded stars known as supernovae. Furthermore, it is threaded by invisible forces, such as gravity and dark matter, which shape the cosmic web and govern the dance of galaxies. The cosmic microwave background radiation, theresidual heat left over from the Big Bang, whispers tales of our universe's fiery birth and subsequent expansion.III. The Search for Extraterrestrial LifeAs we peer deeper into this celestial tapestry, one question looms large: Are we alone in the universe? The discovery of thousands of exoplanets orbiting distant stars has fueled optimism that Earth might not be the sole cradle of life. These alien worlds, some found within the "habitable zones" where liquid water can exist, beckon us to ponder the possibility of extraterrestrial organisms thriving under different conditions. Ongoing missions, such as NASA's James Webb Space Telescope and the search for biosignatures, aim to unveil whether these seemingly habitable planets indeed harbor life, thus rewriting our understanding of our place in the cosmos.IV. Challenges and Future ProspectsExploring the universe is an audacious endeavor fraught with challenges, including the vast distances involved, harsh space environments, and the limitations of current technology. However, advancements in fields like astrophysics, aerospace engineering, and artificial intelligence hold promise for surmounting these obstacles.Space telescopes with unprecedented resolution will enable us to observe the universe in greater detail, while interstellar travel concepts like nuclear fusion propulsion and light sails could potentially revolutionize our ability to traverse the cosmos. Moreover, the pursuit of establishing permanent human settlements on other planets, such as Mars, signifies our aspirations to become a multi-planetary species and secure humanity's future among the stars.In conclusion, the universe, a boundless expanse of celestial marvels and profound mysteries, continues to entice and challenge us. As we delve deeper into its secrets, we not only broaden our understanding of the cosmos but also gain invaluable insights into our own existence. The quest to explore and comprehend this magnificent realm reflects our innate curiosity and unyielding spirit of exploration, promising a future filled with groundbreaking discoveries and paradigm-shifting revelations about the universe we call home.。

第39卷第4期2022年12月World Nuclear Geoscience世界核地质科学Vol.39No.4Dec .2022不整合面型铀矿床经验勘查模型郭春影1，2，裴柳宁3，刘梦魁1，2，韩军1，2（1．核工业北京地质研究院，北京100029；2．中核集团铀资源勘查与评价技术重点实验室，北京100029；3.核工业二〇三研究所，陕西西安712000）［摘要］不整合面型铀矿床是世界铀资源的主要矿床类型之一，具有重要的经济价值。

我国对不整合面型铀矿床的探索一直没有重要突破。

在概述不整合面型铀矿床勘查发现历史、分类的基础上，重点介绍了国际原子能机构最新的经验勘查模型分类及以雪茄湖（Cigar Lake ）、麦克阿瑟河（McArthur River ）、鹰角（Eagle Point ）和千年（Millennium ）矿床为代表的分类端元矿床地质特征。

最后概略分析了我国华北陆块若干地区不整合面型铀矿成矿条件和找矿前景，提出进一步探索不整合面型铀矿床的工作建议。

［关键词］不整合面型铀矿床;经验勘查模型;成矿前景;华北［文章编号］1672-0636（2022）04-0646-14［中图分类号］P611［文献标志码］AEmpirical Classification and End Members of Unconformity-related Uranium DepositsGUO Chunying 1,2，PEI Liuning 3，LIU Mengkui 1,2，HAN Jun 1,2（NC Beijing Research Institute of Uranium Geology,Beijing 100029,China ；NC Key Laboratory of Uranium Resource Exploration and Evaluation Technology,Beijing,100029,China ；3.Research Institute No.203,CNNC,Xi an,Shaanxi 712000,China ）Abstract:Unconformity -related uranium deposits are one of the most important types of uranium resources in the world and have a great economic value.The exploration for unconformity -related uranium deposits has achieved no important findings for several decades.In this paper,we summarized briefly the world s exploration history and classifications of unconformity -related uranium deposits,andreported in detail the new empirical classification of unconformity -related uranium deposits and its four end members represented by Cigar Lake,McArthur River,Eagle Point and Millennium deposits all inthe Athabasca basin.The conditions and prospecting potential for unconformity -related uranium deposits in North China are analyzed to provide some suggestion on further prospecting for unconformity -related uranium deposits.Keywords:unconformity -related uranium deposit;empirical model;uranium prospecting;NorthChina不整合面型铀矿床是全球重要的天然铀资源，以品位高、储量大、经济效益好著称，是国际上铀矿勘查的主要目标类型之一。

a r X i v :g r -q c /0607043v 2 2 O c t 2006DF/IST-4.2006Lorentz Symmetry Derived from Lorentz Violation in the BulkOrfeu Bertolami ∗and Carla Carvalho †Departamento de F´ısica,Instituto Superior T´e cnico Avenida Rovisco Pais 1,1049-001Lisboa,PortugalAbstractWe consider bulk fields coupled to the graviton in a Lorentz violating fashion.We expect that the overly tested Lorentz symmetry might set constraints on the induced Lorentz violation in the brane,and hence on the dynamics of the interaction of bulk fields on the brane.We also use the requirement for Lorentz symmetry to constrain the cosmological constant observed on the braneI.INTRODUCTIONLorentz invariance is one of the most well tested symmetries of physics.Nevertheless, the possibility of violation of this invariance has been widely discussed in the recent liter-ature(see e.g.[1]).Indeed,the spontaneous breaking of Lorentz symmetry may arise in the context of string/M-theory due to the existence of non-trivial solutions in stringfield theory[2],in loop quantum gravity[3],in noncommutativefield theories[4,5]or via the spacetime variation of fundamental couplings[6].This putative breaking has also implica-tions in ultra-high energy cosmic ray physics[7,8].Lorentz violation modifications of the dispersion relations viafive dimensional operators for fermions have also been considered and constrained[9].It has also been speculated that Lorentz symmetry is connected with the cosmological constant problem[10].However,the main conclusion of these studies is that Lorentz symmetry holds up to about2×10−25[1,8].Efforts to examine a putative breaking of Lorentz invariance have been concerned mainly with the phenomenological aspects of the spontaneous breaking of Lorentz symmetry in particle physics and only recently have the implications for gravity been more closely studied [11,12].The idea is to consider a vectorfield coupled to gravity that undergoes spontaneous Lorentz symmetry breaking by acquiring a vacuum expectation value in a potential.Moreover,recent developments in string theory suggest that we may live in a braneworld embedded in a higher dimensional universe.In the context of the Randall-Sundrum cosmo-logical models,the warped geometry of the bulk along the extra spacial dimension suggests an anisotropy which could be associated with the breaking of the bulk Lorentz symmetry.In this paper we study how spontaneous Lorentz violation in the bulk repercusses on the brane and how it can be constrained.We consider a vectorfield in the bulk which acquires a non-vanishing expectation value in the vacuum and introduces spacetime anisotropies in the gravitationalfield equations through the coupling with the graviton.For this purpose, we derive thefield equations and project them parallel and orthogonally to the brane. We then establish how to derive brane quantities from bulk quantities by adopting Fermi normal coordinates with respect to the directions on the brane and continuing into the bulk using the Gauss normal prescription.We parameterize the worldsheet in terms of coordinates x A=(t b,x b)intrinsic to the ing the chain rule,we may express the brane tangent and normal unit vectors interms of the bulk basis as follows:ˆe A=∂∂xµ=XµAˆeµ,ˆe N=∂∂xµ=Nµˆeµ,(1)withgµνNµNν=1,gµνNµXνA=0,(2) where g is the bulk metricg=gµνˆeµ⊗ˆeν=g ABˆe A⊗ˆe B+g ANˆe A⊗ˆe N+g NBˆe N⊗ˆe B+g NNˆe N⊗ˆe N(3)To obtain the metric induced on the brane we expand the bulk basis vectors in terms of the coordinates intrinsic to the brane and keep the doubly brane tangent components only. It follows thatg AB=XµA XνB gµν(4)is the(3+1)-dimensional metric induced on the brane by the(4+1)-dimensional bulk metric gµν.The induced metric with upper indices is defined by the relationg AB g BC=δA C.(5)It follows that we can write any bulk tensorfield as a linear combination of mutually orthogonal vectors on the brane,ˆe A,and a vector normal to the brane,ˆe N.We illustrate the example of a vector Bµand a tensor Tµνbulkfields as followsB=B Aˆe A+B Nˆe N,(6)T=T ABˆe A⊗ˆe B+T ANˆe A⊗ˆe N+T NBˆe N⊗ˆe B+T NNˆe N⊗ˆe N.(7) Derivative operators decompose similarly.We write the derivative operator∇as∇=(XµA+Nµ)∇µ=∇A+∇N.(8)Fixing a point on the boundary,we introduce coordinates for the neighborhood choosing them to be Fermi normal.All the Christoffel symbols of the metric on the boundary are thus set to zero,although the partial derivatives do not in general vanish.The non-vanishing connection coefficients are∇Aˆe B=−K ABˆe N,∇Aˆe N=+K ABˆe B,∇Nˆe A=+K ABˆe B,∇Nˆe N=0,(9)as determined by the Gaussian normal prescription for the continuation of the coordinates offthe boundary.For the derivative operator∇∇wefind that∇∇=gµν∇µ∇ν=g AB[(XµA∇µ)(XνB∇ν)−XµA(∇µXνB)∇ν]+g NN[(Nµ∇µ)(Nν∇ν)−Nµ(∇µNν)∇ν] =g AB[∇A∇B+K AB∇N]+∇N∇N.(10)We can now decompose the Riemann tensor,Rµνρσ,along the tangent and the normal directions to the surface of the brane as followsR ABCD=R(ind)ABCD+K AD K BD−K AC K BD,(11) R NBCD=K BC;D−K BD;C,(12)R NBND=K BC K DC−K BC,N,(13) from which wefind the decomposition of the Einstein tensor,Gµν,obtaining the Gauss-Codacci relationsG AB=G(ind)AB +2K AC K CB−K AB K−K AB,N−12 −R(ind)−K CD K DC+K2 .(16) II.BULK VECTOR FIELD COUPLED TO GRA VITYWe consider a bulk vectorfield B with a non-trivial coupling to the graviton in afive-dimensional anti-de Sitter space.The Lagrangian density consists of the Hilbert term, the cosmological constant term,the kinetic and potential terms for B and the B–graviton interaction term,as followsL=14BµνBµν−V(BµBµ±b2),(17)where Bµν=∇µBν−∇νBµis the tensorfield associated with Bµand V is the potencial which induces the breaking of Lorentz symmetry once the Bfield is driven to the minimumat BµBµ±b2=0,b2being a real positive constant.As discussed in the introduction,this model has been proposed in order to analyse the impact on the gravitational sector of the breaking of Lorentz symmetry[11,12].Furthermore,in the present modelκ2(5)=8πG N= M3P l,M P l is thefive-dimensional Planck mass andλis a dimensionless coupling constant that we have inserted to track the effect of the interaction.In the cosmological constant termΛ=Λ(5)+Λ(4)we have included both the bulk vacuum valueΛ(5)and that of the braneΛ(4),described by a brane tensionσlocalized on the locus of the brane,Λ(4)=σδ(N).By varying the action with respect to the metric,we obtain the Einstein equation1Tµν,(18)2where1Lµν=[∇µ∇ρ(BνBρ)+∇ν∇ρ(BµBρ)−∇2(BµBν)−gµν∇ρ∇σ(BρBσ)](20)2are the contributions from the interaction term andTµν=BµρBνρ+4V′BµBν+gµν −1+2λ[B C(K CD;D−K;C)+B N(K CD K CD−K;N)]=0,(24)parallelly and orthogonally to the brane respectively,which we include here for the purpose of illustration.Next we proceed to derive the induced equations of motion for both the metric and the vectorfield in terms of quantities measured on the brane.The induced equations on the brane are the(AB)projected components after the singular terms across the brane are subtracted out by the substitution of the matching conditions.Considering the brane as a Z2-symmetric shell of thickness2δin the limitδ→0,derivatives of quantities discontinuous across the brane generate singular distributions on the brane.Integration of these terms in the coordinate normal to the brane relates the induced geometry with the localization of the induced stress-energy in the form of matching conditions.First we consider the Einstein equations and then the equations of motion for B which,due to the coupling of B to gravity,will also be used as complementary conditions for the dynamics of the metric on the brane.Combining the Gauss-Codacci relations with the projections of the stress-energy tensor and the interaction source terms,we integrate the(AB)component of the Einstein equation in the coordinate normal to the brane to obtain the matching conditions for the extrinsic curvature across the brane,i.e.the Israel matching conditions.From the Z2symmetry it follows that B A(−δ)=+B A(+δ)but that B N(−δ)=−B N(+δ),and consequently that (∇N B A)(−δ)=−(∇N B A)(+δ)and(∇N B N)(−δ)=+(∇N B N)(+δ).Moreover,g AB(N=−δ)=+g AB(N=+δ)implies that K AB(N=−δ)=−K AB(N=+δ).Hence,wefind for the(AB)matching conditions that12 +δ−δdN −g ABΛ(4)λ+component,we note thatG AN =K AB ;B−K ;A=−∇B+δ−δdN G AB=−κ2(5)∇B T AB =0(26)which vanishes due to conservation of the induced stress-energy tensor T AB on the brane.From integration of the (NN )component in the normal direction to the brane,we find the following junction condition∇C (B C B N )+3KB N B N −K CD B C B D =σ,(27)which we substitute back in,obtaining12−R(ind )−K CD K CD +K2=14B CD B CD −V+1which becomes∇C B C +λKB N =0.(32)The junction conditions Eq.(30)and Eq.(32)offer the required (4+1)boundary conditions respectively for B A and B N on the brane.Substituting the junction condition for B A back in Eq.(23)and using the result from G AN =0,we find for the induced equation of motion for B A on the brane that∇C (∇C B A −∇A B C )+2K AC (∇C B N )−2V ′B A +2λB CR (ind )AC+2K AD K DC=0.(33)Similarly,substituting the junction condition for B N back in Eq.(24)we obtain∇C ∇C B N −2V ′B N +λ[K (∇N B N )+B N K CD K CD ]=0.(34)Thus,Eq.(30)provides the value at the boundary for ∇N B A and Eq.(34)provides that for ∇N B N .Using the results derived above in the Israel matching conditions we find that12(∇A B B )B N +(∇B B A )B N+B A B C K CB +K AC B C B B −K AB B N B N+g AB−∇C (B C B N )+12KB N B N +1κ2(5)G (ind )AB +2K AC K BC −K AB K +12−B AC B BC −4V ′B A B B +12g AB−2∇C ∇D (B C B D )−∇C ∇C (B N B N )+12B N ∇C ∇C B N −20V ′B N B N+4(K CD −g CD K )∇D (B C B N )+6K CD B D (∇C B N )+KB C (∇C B N )+B C B D R (ind )CD+9K CD K CD B N B N +14K CE K DE B C B D −Kσ+1+KB N(∇A B B+∇B B A)−2K AB B N(∇C B C) 8−∇C B C =0(38)−K CD B C B D =σ(39)1κ2(5)12−1κ2(5)G (ind )AB+2K AC K BC −12g ABR(ind )−K CD K CD −K2+g AB Λ(5)−1214B B ∇C (5∇C B A −9∇A B C )+∇A ∇C ( B B B C )+∇B ∇C ( B A B C )−2(∇C B A )(∇C B B )+52B B BC R (ind )AC −6K AC K BD B C B D +2K AB σ+1κ2(5)G (ind )AB+2K AC K BC −12g ABR (ind )−2K CD K CD −K 2+g AB Λ(5)=12 B A B C R (ind )CB +52g ABB C B D R (ind )CD+2Kσ.(44)Hence,in order to obtain a vanishing cosmological constant and ensure that Lorentz in-variance holds on the brane,we must impose respectively thatΛ(5)=Kσ(45)and that2K AC K BC−12g AB R(ind)−2K CD K CD−K2=κ2(5) 54 B B B C R(ind)AC+1the matching of the observed cosmological constant in four dimensions.This tuning does not follow from a dynamical mechanism but is imposed by phenomenological reasons only. From this point of view,both the value of the cosmological constant and the Lorentz symmetry seem to be a consequence of a complexfine-tuning.We aim to further study the implications of our mechanism by considering also the inclusion of a scalarfield in a forthcoming publication[14].AcknowledgmentsC.C.thanks Funda¸c˜a o para a Ciˆe ncia e a Tecnologia(Portuguese Agency)forfinancial support under the fellowship/BPD/18236/2004. C.C.thanks Martin Bucher,Georgios Kofinas and Rodrigo Olea for useful discussions,and the National and Kapodistrian Uni-versity of Athens for its hospitality.[1]CPT and Lorentz Symmetry III,Alan Kosteleck´y,ed.(World Scientific,Singapore,2005);O.Bertolami,Gen.Rel.Gravitation34(2002)707;O.Bertolami,Lect.Notes Phys.633 (2003)96,hep-ph/0301191;R.Lehnert,hep-ph/0312093.[2]V.A.Kosteleck´y and S.Samuel,Phys.Rev.D39(1989)683;Phys.Rev.Lett.63(1989)224;V.A.Kosteleck´y and R.Potting,Phys.Rev.D51(1995)3923;Phys.Lett.B381(1996)89.[3]R.Gambini and J.Pullin,Phys.Rev.D59(1999)124021;J.Alfaro,H.A.Morales-Tecotland L.F.Urrutia,Phys.Rev.Lett.84(2000)2318.[4]S.M.Carroll,J.A.Harvey,V.A.Kosteleck´y,ne and T.Okamoto,Phys.Rev.Lett.87(2001)141601.[5]O.Bertolami and L.Guisado,Phys.Rev.D67(2003)025001;JHEP0312(2003)013;O.Bertolami,Mod.Phys.Lett.A20(2005)1359.[6]V.A.Kosteleck´y,R.Lehnert and M.J.Perry,Phys.Rev.D68(2003)123511;O.Bertolami,R.Lehnert,R.Potting and A.Ribeiro,Phys.Rev.D69(2004)083513.[7]H.Sato,T.Tati,Prog.Theor.Phys.47(1972)1788;S.Coleman and S.L.Glashow,Phys.Lett.B405(1997)249;Phys.Rev.D59(1999)116008;L.Gonzales-Mestres, hep-ph/9905430.[8]O.Bertolami and C.Carvalho,Phys.Rev.D61(2000)103002.[9]O.Bertolami and J.G.Rosa,Phys.Rev.D71(2005)097901.[10]O.Bertolami,Class.Quantum Gravity14(1997)2785.[11]V.A.Kosteleck´y,Phys.Rev.D69(2004)105009;R.Bluhm and V.A.Kosteleck´y,Phys.Rev.D71(2005)065008.[12]O.Bertolami and J.P´a ramos,Phys.Rev.D72(2005)044001.[13]M.Bucher and C.Carvalho,Phys.Rev.D71(2005)083511.[14]O.Bertolami and C.Carvalho,in preparation.。

自旋重取向穆斯堡尔谱
自旋重取向穆斯堡尔谱是研究核激发态的一种重要方法。

该方法
通过测量核激发态的寿命及其在晶格中的局域程度，从而得到关于物
质各种性质的信息。

自旋重取向穆斯堡尔谱主要应用于研究核磁偶极
相互作用、电场梯度和晶体场效应等。

在实验中，样品被置于恒磁场中，同时用高能γ射线对其进行
激发。

随着时间的推移，激发态的能量将通过发射γ射线而逐渐衰减。

该衰减过程可以通过测量γ射线的能量和衰减时间来观测到。

这种衰
减过程也称为自旋重取向。

通过对自旋重取向过程的测量，可以获得核的平均激发寿命、激
发态能级的分布、晶格的电场梯度和晶格势场参数等信息。

这些参数
可以在物理、化学、材料科学等领域中得到广泛的应用。

总的来说，自旋重取向穆斯堡尔谱是一种非常重要的研究核物理
性质的方法，其广泛应用于多个学科领域中。

The gravitational field energy density for symmetrical and asymmetrical systemsRoald SosnovskiyTechnical University, 194021, St. Petersburg, RussiaE-mail:rosov2@yandexAbstract. The relativistic theory of gravitation has the considerable difficulties by description of the gravitational field energy. Pseudotensor t 00 in the some cases cannot be interpreted as energy density of the gravitational field. In [1] the approach was proposed, which allow to express the energy density of such a field through the components of a metric tensor. This approach based on the consideration of the isothermal compression of the layer consisted of the incoherent matter. It was employ to the cylindrically and spherically symmetrical static gravitational field. In presented paper the approach is developed.1. Introduction. The problem of the gravitational field energy discussed a long time [2], [3]. However, pseudotensor differs from author to author reflecting the ambiguity in defining gravitational field energy density [3]. In [1] the approach has proposed allows one to express the energy density of such a field through the components of a metric tensor. This approach based on the consideration of the isothermal compression of a layer consisted of the incoherent matter in the field of the infinitesimal thin material shell by fulfillment of the requirements [4]: (a) the local energy conservation law should be fulfilled and (b) the correspondence principle should be fulfilled including the energy part.µνt In the presented paper proved, that this approach can be used for asymmetrical systems. Here proved, that the requirement of the invariance of the gravitational field energy density [4] fulfilled. For the cylindrically and spherically symmetrical systems is obtained field energy density formulas, contained only the metric tensor component and his derivative.2. The differential of the gravitational field energyIn [1] has obtained the formulas of the gravitational field energy for the special coordinates, connected with type of symmetry. Here it considered the formula of the field energy for the arbitrary static coordinates systems. The solution is analogous to one in[1].2.1. The isothermal compression. Here it considered the movement of the particles layers when acquired energy of particles has eradiated or dissipated. The movement considered as consisted of discrete infinitesimal steps, when the particles fall free, and in end of step energy of particles has dissipated. Concrete ways of dissipation no discussed. Sufficiently to suppose that such way can be on principle approximately realized. For example, free fall of particles in thin lay on the solid surface with following cooling of the solid.The particles considered as test-particles. However, the change of field, caused with accumulation of the matter on solid surface, calculated after every step. Assume αx is the initial coordinate system, admissible for the system configuration, with metric .0,0=µµνg g Let us consider the displacement of the particles layer from position 111x x = to position 1111x d x x +=. The free particles fall equations are[5] 0=∂∂−⎟⎠⎞⎜⎝⎛∂∂µµτxL x L d d & (1) where τ is the intrinsic time, ·τµµd x d x =& and()νµµνσσx x g x x L &&&21,=, ()321,,x x x g g µνµν= (2) For static system (1),(2) lead to 0000g C x =& (3) where C 0 is constant on all step. From (3) and from equationk i ik x x g xg c &&&+=02002 (4) we get, so far as i x&is small, 000g c C = (5) From formulas (1), (2) for i, k =1,2,3 result02,0021x g xg i k ik &&&= (6) and from (5),(6)002,0021g c g g x i ik kδτ=& (7) where τ is the intrinsic time of particles movement. Components k u of the maximum velocity of free particles fall near by point ),,(321x x x x r may written00,00g g g u iik k β= (8)where ß is infinitesimal coefficient.2.2. The static gravitational field energy. General formulas. The energy of the particles by free fall can obtained from the relation [6]0002g g u mc E ννδ=, τννcd x d u = (9) where δm is rest mass of the particles group. From (3) and so far as 0000g g ννδ= the change of particles energy on way i x d isi i x d g g mc dE ,000022δ−= (10) This energy has dissipated on way i x d . If the local energy conservation law fulfilled then the energy change of particles must result from change of field energy dE f on way i x d . Thereforei i f x d g mc dE ,000022δ= (11)From (8) follow, that the components of the of the particle coordinates mean change is00,00g g g x d kik i λ= (12)and scalar displacement is equalk i ik g g g g dl ,00,0000λ= (13) wherek i ik g g g dlg ,00,0000=λ (14)If substitute λ in (12) and then i x d in (11) then we get dl g g g g mc E d k i ik f ,00,000022δδ−= (15)Here δm and δl are scalars, 00g by 00=i g no depend on the space coordinates transformation. The quantity k i ik g g g ,00,00 is invariant by the space coordinates transformation k i k i x A x = (16)Therefore, d δE f is also invariant.3. Energy of the asymmetrical gravitational field.3.1. The object. Considered the static field of the asymmetric convex smooth infinitesimally thin material shell with surface mass density σc .The quantity σc is a single-valued function of the coordinates of shell point ()3211,x x x x c c =, ()32,x x c c σσ=. It considered the space between a shell and some convex smooth external surface ()3211,x x x x e e = with surface mass density ()32,x x e e σσ=. Assumed, that it known how the metric ik g of the space region between c x and e x to find. This is possible at least by miens of the computer methods [7].3.2. The calculations order. Is considered the motion of N j discrete test particles layers from the external surface to the shell. The motion is discrete; the number of steps is N q . For every layer position, the calculations made for N k · N n points. The every point position determined in coordinate system i x . For every point P(k,n,q) the volume element is built at the vectors ),,(321ii i i i x d x d x d z d z d r r =, i =1,2,3. Let this vectors create the coordinate system ()0000,,,,g g x d j q n k B dz k i k i == (17)One side (dz 2,dz 3) of this element is disposed at the layer position q and the opposite side at the layer position q+1. The vector l d r describe the fall of particle from point P(k,n,q) up to point F(k',n',q+1) at the layer position q+1. For every point P(k,n,q) and every layer j are calculated from (15) the field energy differential d δE f and masse density σ(k',n',q+1,j) for point P(k',n',q+1). Afterwards the layer j arrive the position q = N q metric components g ik calculated for all points P(k,n,q) . The method of such calculation no considered because that does not matter for the purpose of this paper.3.3. The gravitational field integral energy and energy density invariance. Let the volume element is built at the vectors dz i .The mass of the particles group, passed through this element, is equal()()()j q n k dS j q n k j q n k m ,,,,,,,,,⋅=δσδ (18)where δσ(k,n,q,j) is the matter density in the particles layer j and dS(k,n,q,j) – the area of the element (dz 2,dz 3). The mass δm of this element, which is considered as in the one point concentrated, fall from point P(k,n,q) in point F(k,n,q+1) with coordinates z i + dl i . Components dl i can be calculated in coordinates dz i from (12), (17). Component dl 1 = dz 1 andq q pkp k g g g g dl dl ,001,001=,k=2,3 (19)By means interpolation can be calculate the mass δm(n,q+1,j) and mass density δσ(n,q+1,j) for points P(k,n,q+1). Consider the successive pass of the layers through the element of area ()32,dz dz with point P(k,n,q). From (15),(17) after step j = N j the field energy change in volume element is equal ()j q n k s i isN j f g g g g dl dS c q n k dE j ,,,,00,0000222,,⎥⎦⎤⎢⎣⎡⋅⋅=∑δσ (20) where [] depend on (k,n,q,j). The quantities under the symbol Σ are the invariants, therefore dE f (k,n,q) is invariant. The sum of energy in all points of the field is also invariant.The energy density in point P(n,q) is given by()()),(,,,q n dV q n dE q n k w f =, 321dz dz dz g dV я= (21)where dV(n,q) is the volume of the volume element, built at the vectors ()321,,z d z d z d r r r for step j=N j ; z g is determinant of the metric components. The quantity dV is scalar, therefore w(n,q) is invariant.Thus, the approach based on the consideration of the isothermal compression of the layer consisted of the incoherent matter, can be used for asymmetrical systems.4. The transformation of the formulas for field energy density of the symmetrical systems.The formulas for these quantities in the paper [1] maintain, besides the metric tensor components, the field source mass M and the distance to symmetry centre R. As the metric tensor components are the functions of M and R, it is possible to except M and R from these formulas.4.1. The cylindrical symmetry. In [1] there are the formulas000a R R g ⎟⎟⎠⎞⎜⎜⎝⎛=, 204c GM a z = (22) where R – radius, R 0 – radius of the field source, M z – the linear mass density. From (23) followRc GM g g z 2001,004= (23) and energy density 002001,0040022322g g g G c g R GM w z ⎟⎟⎠⎞⎜⎜⎝⎛−=−=ππ (24)4.2. The spherical symmetry. From [1] in this caseRc GM g 20021−=; dx 1=dR; dx 2=Rd θ; dx 3=RSin θd φ (25) and energy density⎥⎦⎤⎢⎣⎡+⎟⎠⎞⎜⎝⎛−=R c GM R c GM GR g сw 2222221ln 1600π (26)or from (25) []G g c g g g GR g g сw ππ321ln 11621,004000020020021,004−≅−+−= (27)4.References1.R.Sosnovskiy.gr-qc 05070162.K.S.Virbhadra.A comment on the energy-momentum pseudotensor of Landau and Lifshitz. Phys. Lett.A 157(1991)1953.J.Katz. gr-qc 05100924. N.V.Mitzkevitsch. Physical fields in general relativity. Nauka, Moskow, 19695.J.L.Martin. General Relativity . N.Y.,19886.A.Logunov. Lectures in relativity and gravitation. A modern Look. Nauka, Moskow,19907. L.Lehner. gr-qc 0106072。

进入平行时空英语作文Title: Exploring Parallel Universes。

In the vast expanse of the cosmos, beyond the realms of our known universe, lies the intriguing concept of parallel universes. The notion that there exist alternate realities, diverging from our own, sparks the imagination and fuels endless speculation among scientists, philosophers, and curious minds alike.One cannot help but wonder: what if there were other versions of ourselves, inhabiting parallel dimensions, living out different lives with alternate choices and outcomes? This hypothetical scenario opens up a realm of possibilities, where the laws of physics may vary, and the course of history could have taken a multitude of divergent paths.In contemplating the existence of parallel universes, one is inevitably drawn to the question of communicationand interaction between these separate realms. If such universes exist, is it possible to traverse the boundaries that divide them? Could there be a means of communication or even travel between parallel dimensions?Theoretical physics offers several intriguing hypotheses regarding the nature of parallel universes. The concept of the multiverse, for instance, suggests that our universe is just one of many existing in parallel, each with its own unique set of physical constants and fundamental laws. According to this theory, there could be an infinite number of universes, each branching off from the others like the branches of a tree, resulting in an incomprehensibly vast cosmic landscape.Another theory proposes the existence of "brane worlds," where our universe is akin to a membrane floating within a higher-dimensional space. In this model, parallel universes may exist on separate membranes, occasionally intersecting or colliding with one another in ways that could potentially be detected through cosmic phenomena or gravitational waves.While these theories remain speculative and largely beyond the realm of empirical observation, advances in theoretical physics and cosmology continue to push the boundaries of our understanding. Experiments conducted at particle accelerators and observatories around the world seek to uncover clues that may lend credence to the existence of parallel universes or offer insights into the fundamental nature of reality.From a philosophical perspective, the concept of parallel universes raises profound questions about the nature of existence and the role of choice in shaping our lives. If every decision we make results in the creation of alternate realities, what does it mean to have free will? Are our lives predetermined, or do we truly have the power to alter the course of our destinies?Exploring the implications of parallel universes also invites speculation about the nature of consciousness and identity. If there are infinite versions of ourselves scattered across parallel dimensions, each making differentchoices and experiencing different outcomes, what defines the essence of who we are? Is there a singular "self" that transcends the boundaries of space and time, or are we merely transient manifestations of probability in an ever-expanding multiverse?In the realm of science fiction, parallel universes have long been a fertile ground for storytelling, providing a canvas for exploring themes of identity, destiny, and the nature of reality itself. Countless novels, films, and television series have delved into the concept, presenting imaginative scenarios ranging from alternate histories to parallel dimensions inhabited by fantastical beings.In conclusion, the concept of parallel universes represents a fascinating intersection of science, philosophy, and imagination. While the existence of such universes remains speculative, the exploration of this idea sparks thought-provoking questions about the nature of reality, the fabric of the cosmos, and the fundamental mysteries that lie beyond the limits of our current understanding. Whether these alternate realities exist onlyin the realm of theory or await discovery beyond the horizon of our knowledge, the exploration of parallel universes continues to captivate the human imagination and inspire wonder about the boundless possibilities of the cosmos.。

SPE 159919裂缝型页岩气藏中多尺度流动的扩展有限元建模M. Sheng1, SPE, G. Li, SPE,中国石油大学(北京), S.N. Shah, SPE, and X. Jin, SPE, 俄克拉何马大学版权所有2012，石油工程师学会这篇是准备在美国德克萨斯州圣安东尼奥2012年10月8-10日举行的SPE年度技术会议和展览上进行发表的文章。

本文是SPE程序委员会选定审查的，当中未确认作者所提交的摘要信息。

本文的内容没有被石油工程师学会审查的，也未进行作者更正。

材料不一定反映石油工程师在社会的任何位置，管理人员或成员。

在没有石油工程师的社会的书面同意的情况下禁止电子复制、分发、或储存该文章的任何部分。

印刷复制许可限制在300字以内的摘要；插图不可以被复制。

摘要必须明显包含和承认SPE所有的版权。

摘要一个页岩气的经济生产方案需要更好地了解其气体流动方式和建立合适的油气藏模型。

在复杂的裂缝中和多尺度流动通道中气体流动行为的复杂程度加强。

这篇文章结合改进页岩气运输模型和扩展有限元建模(XFEM)来描述页岩气的主要流动机制和其离散裂隙网络。

页岩气的被视为具有离散裂缝的双重渗透介质。

离散裂缝不需要划分网格，它可以将给定的位置、长度和取向放在任何地方。

岩石变形与瓦斯流动的隐式耦合反映页岩气的应力敏感性。

此外，在破碎断裂中的置换和基质孔隙水压力被视为不连续的近似函数集合。

用计算机编码的开发一个模型，此模型以双渗介质固结问题为验证代码。

结果表明与常规压力场的连续裂缝模型的比较，页岩气的压力场明显被离散裂缝干扰。

因此，将页岩气所处裂隙认为是多孔介质离散裂缝是很重要的。

为提高上述模型的应用，页岩气储层提出了一个案例研究。

模拟在裂缝性储层中以双模式网络为基础。

因为前者使孔隙水压力场耗尽对称，显而易见正交裂隙网络是一个与斜裂缝相反的理想模式。

此外，敏感区域是控制压力衰减的主要因素。

结果表明，所提出的模型和代码是能够模拟页岩气藏所处的离散裂隙网络的。

gravitational potential公式下载温馨提示：该文档是我店铺精心编制而成，希望大家下载以后，能够帮助大家解决实际的问题。

文档下载后可定制随意修改，请根据实际需要进行相应的调整和使用，谢谢!并且，本店铺为大家提供各种各样类型的实用资料，如教育随笔、日记赏析、句子摘抄、古诗大全、经典美文、话题作文、工作总结、词语解析、文案摘录、其他资料等等，如想了解不同资料格式和写法，敬请关注!Download tips: This document is carefully compiled by the editor. I hope that after you download them, they can help you solve practical problems. The document can be customized and modified after downloading, please adjust and use it according to actual needs, thank you!In addition, our shop provides you with various types of practical materials, suchas educational essays, diary appreciation, sentence excerpts, ancient poems, classic articles, topic composition, work summary, word parsing, copy excerpts, other materials and so on, want to know different data formats and writing methods, please pay attention!重返重力潜能：揭秘引力潜能公式引言引力是宇宙中最基本、最神秘的力量之一。

在断裂力学领域有很多杰出的学者，以下是其中的一位：锁志刚教授在力学与材料科学的诸多领域进行了开创性研究，包括界面断裂、电迁移、铁电致材料失效、纳米尺度的相分离自组装、电子封装力学、薄膜力学等。

他曾获得过美国总统奖、全美青年工程师金质大奖、德国红堡基金会红堡高级大奖、ALCOA 基金会研究奖、普林斯顿大学工程委员会教学优秀奖、计算机工程及科学国际会议Eric Reissner奖、全美机械工程学会应用力学奖等多个奖项，在界面断裂力学领域有着深厚的造诣和卓越的贡献。

如果你想了解更多关于界面断裂力学的信息，可以继续向我提问。

平板边界层中湍流的发生与混沌动力学之间的联系
平板边界层中湍流的发生与混沌动力学之间的联系
通过对平板边界层流动中的测量数据的仔细分析,证实了在平板边界层的湍流发生的过程中存在着奇怪吸引子.将这一结论与先前的转捩动力学分析结果相比较,证明了湍流的发生本身具有着混沌动力学本质,从而在平板边界层中的湍流发生与混沌之间建立了联系.
作者：李睿劬李存标作者单位：李睿劬(清华大学工程力学系,北京,100084)
李存标(北京大学湍流与复杂系统研究国家重点实验室,北京,100871)
刊名：物理学报ISTIC SCI PKU英文刊名：ACTA PHYSICA SINICA 年，卷(期)：2002 51(8) 分类号：O4 关键词：边界层转捩湍流的发生混沌奇怪吸引子。

宇宙演化膨胀坍缩理论张少勇【摘要】宇宙大爆炸理论仍有许多核心问题没有解决.建立了宇宙从大爆炸,经过膨胀、坍缩,最终回到起点的宇宙演化膨胀坍缩理论.阐述了大爆炸的形成,引起爆炸原因,论述了宇宙加速膨胀、暗能量、引力波等宇宙学关键问题.%In the big bang theory , many key puzzles have not been solved .This paper presents an expansion collapse theory of cosmological evolution that the universe originated from the big bang , expanding at beginning , then contracting , and finally collapsing to the origin of the big bang .Some answers are given to the formation of the big bang, the triggering mechanism of the big bang , the accelerating expansion of universe , dark energy and gravitational waves .【期刊名称】《哈尔滨理工大学学报》【年(卷),期】2017(022)006【总页数】6页(P116-121)【关键词】大爆炸;暗能量;加速膨胀;引力波;超光速【作者】张少勇【作者单位】哈尔滨理工大学理学院,黑龙江哈尔滨150080【正文语种】中文【中图分类】P159.3With the aid of large-scale str ucture theories of the universe in Einstein′s general relativity, many theories about cosmic evolution are proposed[1-6], such as string theories, brane theories and bang theories. In 1927, Lematre presented modern bang theory[7-8]. In 1929 Edwin Hubble found that the entire universe was expanding uniformly. After the universe was discovered in accelerating expansion, the big bang theory has become the main theory of cosmic evolution. However, the big bang theory has not explained many kernel questions, such as how the singularity of the big bang was shaped, what triggered the big bang, why our universe is in accelerating expansion, what dark energy[9-11] is and why gravitational waves are too hard to detect. This paper represents an expansion collapse theory of cosmological evolution, which reveals the forming process of the singularity of the big bang and the mechanism that triggered the big bang, answers the reason for accelerating expansion, discusses the essence of dark energy and gravitational waves. The cosmological evolution process stars from the big bang, and then expands and finally collapses to the original singularity.The light ball is a space ball in the universe, at the center of the big bang, with the radius that light can reach from the time of the big bang to date. The light ball is growing at the speed of light with the passage of time. All objects that we can observe are within the light ball. Outside the light ball, it is a world of super-velocity of light.According to Newton Law, any body moving at the speed lower than light still keeps inertial motion after the force acted on it is cancelled. Anothertype of matter moves with wave mode at the speed of light, such as electromagnetic waves, light, etc.For convenience of discussion, all matter moving at the speed lower than light is defined as inertial matter. The rest, which moves with wave mode at speed equal to or faster than light, is defined as wave matter.Inertial matter travels at a speed lower than light, moves in a straight line, occupies a certain amount of space, but does not fill all the space. Wave matter travels at a speed equal to or faster than light, propagates with wave mode, does not occupy any space, but fills all space which it can reach. Any limited space can be filled with unlimited amount of electromagnetic waves. The faster wave matter moves, the more energy it has. Light is the point of division of inertial matter and wave matter. Light has part of properties of inertial matter and wave matter. This exactly explains the phenomenon of wave-particle duality of light.Before the big bang, matter in the universe was attracted by gravity, converged together and formed a huge black hole. By the accumulation of more matter, the temperature and pressure, and then speeds and energy in the black hole rose gradually to higher degree. In such huge black hole with high temperature and great pressure, matter in the kernel could not exist or move in form of articles. It could only exist by way of wave with high speed. When such waves got enough energy to escape tight bound to the black hole, the big bang happened. All matter escaped outward at the initial speed endowed by the big bang.Light cannot escape from black holes, hence the speed and energy ofwaves propagating out from the big bang must be faster and higher than light. On the other hand, only such waves with faster speed and higher energy than light can create the big bang. Right after the big bang, most matter propagates with faster speed than light. At early stage， the propagating speed is actually reduced by the gravity. After a long periodof time, the matter outside the light ball is coming to constitute a majority of the cosmic matter. When gravitational force outside the light ball is greater than that inside the light ball, matter inside the light ball starts to propagate and this propagating is accelerated.All matter within or out of the light ball is attracted by gravity. Hence propagating speed of superluminal matter outside the light ball is reduced. However the propagating speed within the light ball is accelerated outward. When the propagating speed of superluminal matter outside the light ball is coming to stop, the matter outside the light ball begins to contract inward. Then the whole universe come to contract and at last collapses to a point again. A next big bang will happen!The big bang theory has some unsolved problems. Various theories give many explanations, but they are not as credible as expected. No one theory has solved the questions completely. This expansion collapse theory of cosmological evolution may explain some problems about the big bang theory.What the singularity of the big bang is, how it is formed, how it could contain so much matter of the universe in it, what the physical form before the big bang is like, what triggers the big bang? So many questions likethose have not been explained properly.The center of this black hole is just the singularity as described as in the big bang theory. In such black hole, matter gathered was so much, gravity was so great, temperature was so high, which matter could not exist in form of particles but could only exist in form of waves. Just for the reason described above that wave matter does not occupy any space, the black hole could hold so much matter of the universe in it, accumulated by gravitation,The big bang happened after the energy of waves exceeded the gravitation of the black hole. After this moment, all matter in the black hole began to propagate outward from the center of the singularity of the black hole, with the initial speed endowed by the big bang. The velocity of most propagating waves were faster than the speed of light, for the reason that light, with the speed of light, cannot escape from a black hole. The energy of light could not trigger the big bang.In the big bang theory, dark energy is assumed to explain the phenomenon of the propagation of our universe. What is dark energy? Many articles have been presented to date, but they discuss the cosmic propagation basically on the assumption of repelling force or negative gravitation of dark energy. Paper[1] gave a theoretical model for dark energy. Papers[2-3] analyzed dark energy by adjusting Einstein′s equation or parameters of negative energy model. However, the essence of dark energy is not explained properly. No scientific experiments today can examine what it is. The concept of dark energy is perhaps created to try toexplain what 70% of universe is. At the same time, repelling force is endowed in order to describe the propagation of our universe.If dark energy, as described as in other theories, can fulfill the universe where we have probed to date. This dark energy should or basically should be uniformly distributed in the universe. Repelling force should be pointing in all directions. But this could lead to that the joint forces should be zero or insignificant. Thus, stars could not be affected by any repelling force and could not move significantly. On the other hand, even if the repelling forces are not uniformly distributed somewhere, or the joint forces are big enough to influence some stars, the moving directions of those stars are not certain in line with that of the cosmic propagation. In other words, those influenced stars may move in all possible directions and some stars may come near and nearer. They do not dilate outward together! If our universe is congested with dark energy or repelling forces in it, all stars would, on the whole, move out of order, not in the direction of cosmic propagation. This contradicts what we have observed that all stars are accelerated to propagate outward.According to the hypothesis of dark energy of present theories, the repelling forces of dark energy have existed right after the big bang and have been ubiquitous. The repelling forces of dark energy (70% of cosmic matter) are stronger than the universal gravitation. In such environment of powerful repelling forces, the diffuse cosmic matter could not gather and form stars and galaxies by the gravitation. Our universe would be like a bowl of more and more thin gruel, which would be in chaos for ever.In one word, the forces that help cosmic matter to accelerate propagation outward cannot exist within our visible universe. They can only exist outside the light ball.After long years′ observatio n, we have found the universe is not in condensing by gravitation, but in accelerating expansion. What results in the accelerating expansion if it is not dark energy?The essential reason for cosmic expansion is that the gravitation outside the light ball is stronger than that within the light ball. The joint force accelerates the matter in the light ball or our visible universe to expand outward, or the gravitation outside the light ball tows the matter within the light ball to expand outward. It is just like the phenomenon that air balloon will expand outward in negative pressure. The gravitation outside the light ball is originated in the superluminal matter which is produced in the big bang. The total quantity of such matter is much more than that of matter within the light ball. This is just the reason for the repelling forces of the 70% dark energy.Right after the big bang, all matter propagated at the initial velocities endowed by the big bang. After some period of time, the universe began to accelerate the propagation. What triggered the accelerating expansion process? No answer is given in present theories. A concept of repelling forces is supposed to explain the accelerating expansion. Why have the repelling forces not worked at the early stage after the big bang?After the big bang, most part of matter propagated with super-velocity of light. At this early stage, main part of matter remained within the light balland the propagation is not accelerated. On the contrary, the propagating velocities are reduced by the cosmic gravitation on the whole. After a long time of propagation，superluminal matter outside the light ball constitutes main part of the universe. When the gravitation outside the light ball was greater than that within the light ball, the matter within the light ball began to accelerate to expand. This is why the universe began to accelerate the propagation after some period of time later. The so-called dark energy or repelling force, what we do not have found, also helps to prove the phenomenon that the matter or the gravitation outside the light ball is much greater than that within the light ball.The repelling force of Casimir-Lifshitz is supposed to be a part of the repelling forces. However, this kind of force is inversely proportional to the four square of the distance. It is too small in the large scale of universe. On the other hand, it should be scattered randomly everywhere in universe and the vector sum of such Casimir-Lifshitz′s repelling forces, just like that of dark energy, should be close to zero.The superluminal matter is in a state of waves, which pervades in the universe where it can arrive. Waves with super velocity of light can not exist in particles, nor can they gather to evolve in any kind of stars. Outside the light ball, it is only a world of superluminal waves.No clear future results are given in the big bang theories and the universe is considered to expand slowly and continuously in the dark.Any matter in the universe is influenced by the gravitation. The superluminal matter has energy and therefore has mass. The matteroutside the light ball is also attracted by the gravitation of all matter in the universe, in the direction to the center of the big bang. The propagating velocity of superluminal matter outside the light ball is reduced. The universe will be condensing after the propagating speed of matter outside the light ball stops. Finally, our universe will condense to a point again. A new huge black hole will appear and prepare a next big bang. Perhaps, our present universe is one of many cycles of expansion collapse! Gravitational waves are detected 100 years later after Einstein′s prediction. Why does it take as so many years? What really are they and where do they hide in the universe?Gravitational waves originated from gravitation. They exist in the whole universe all the time. Gravitation and then gravitational waves appear as long as matter exists. Gravitational waves are continuous waves and emitted by matter. Whenever encountering something, gravitational waves will drag it to the matter by which gravitational waves are emitted. This is the universal gravitation.Gravitational waves would be considered as innumerable wave line originating from one point in space coordinates system. They fill any space where they arrive, just as electromagnetic waves are emitted by a magnet. The gravitation of each line of gravitational waves is too weak, but the integral force of enough gravitational waves is obvious and equal to the gravitation of the matter, obeying the law of universal gravitation.Now that gravitational waves exist everywhere, why is it hard to detect? First, the energy of each line of gravitational waves is too weak. Second,gravitational waves are continuous and changes of their energy are too small in local range (even in quite a large range). Normally there is no energy mutation. Third, it is the most important that we are living in an ocean of gravitational waves. Every thing, including detecting equipments, is effected equally by gravitational waves. We could not feel or detect temperature if we lived in a constant temperature world all the time. Energy mutation of gravitational waves can only be created by changes of matter mass, not by gravitational waves themselves. Compared with speeds of gravitational waves, mass mutation in explosion of stars is slow and continuous and cannot be detected in local space-time. It may be easier in large scale or long duration. At present level of science and technology, it is hard to detect gravitational waves.In the big bang, the sudden change of huge mass of the black hole is big enough to disturb the gravitational field existing before the big bang. The superluminal waves from the big bang, especially with lower speed close to light, have efficiently superposed disturbance on gravitational waves. The gravitational waves scientists have detected this year could be the remains of disturbance by the superluminal waves from the big bang. With the development of technology and the detection means, we can detect more evidence of gravitational waves in the future.According to the principle of Einstein′s invariance of light speed, the experiment of limit speed of light by W.Bertozzi[4] and other experiments (such as Michelson-Morlay，Phys.Lett.，T.Alvager at al. & J.Bradley), the light velocity is the maximum speed of particles. This maximum velocity iswidely accepted. Although this absolute maximum velocity is somehow not easy to understand, Einstein′s[5] theories and other accepted theories can not prove the existence of the super-velocity of light. The large hadron collider (LHC) has verified the existence of the Higgs boson. The supper-velocity of light is created in extreme conditions, such as in the big bang, so it is hard now to prove the existence of the supper velocity of light only by our present scientific methods.Einstein′s theories of relativity do not negate the correctness of Newton′s laws for particles in low speed. The super-velocity of light also does not negate the correctness of Einstein′s theories of relativity in speed not more than light. The topic of the super-velocity of light runs counter to modern physics. However, hypothesis of the super velocity of light can explain many unsolved puzzles of the big bang. Now we infer the existence of the supper velocity of light in the following several aspects.Summing up all the methods testing the inexistence of the supper velocity of light, we find that all experiments are taken in the system of light. We use the methods and knowledge in the system of light to verify some nature outside the system of light. It is hard or even impossible in the world of light to prove the existence of the super-velocity of light by the methods and knowledge in the system of light.According to the mass energy formula of relativity,speed of any particles cannot reach the velocity of light. When the speed of a particle is close to the velocity of light, its mass will be close to infinity and the energy that the particle needs to accelerate will be also close toinfinity. In a ll accelerating experiments, including γ ray, no matter how much energy we apply, Speeds of particles can not reach the velocity of light, not to exceed it. However, light can travel at the velocity of light easily. It is just the reason that light travels at wave. A particle moving at the speed close to light, just like γ ray, shows some properties of light, with which it can travel fast and far. In testing and deducing the theories of the maximum light velocity, the objects we take to study are inertial particles. The theories of the maximum light velocity are correct to all kinds of inertial particles.Wave mater is out of restrictions of the theories of the maximum light velocity. On the contrary, the minimum velocity limit of wave matter is the velocity of light. The wave matter, we discuss here, is pure wave, excluding the properties of inertial particles, nor the corpuscular property of wave-particle dualism.In our visible universe with the maximum light velocity, the value in the factor of the Lorenz transform cannot be negative, which is the base of the theories of the maximum light velocity. However, light can travel at the maximum light velocity. Light is exceptive and is not suitable for this formula. The reason is that the Lorenz transform is built on the presupposition of principle of constancy of light velocity and the maximum light velocity, to study the theories of inertial particles. Hence, the supper velocity of light is not suitable for this formula. In another way, when the speed is greater than that of light, the factor is an imaginary number. This perhaps depicts some properties of the supper velocity of light.A new cosmic complete evolution model from the big bang, expansion, collapse and finall to another starting point is established in this expansion collapse theory of cosmological evolution, which solves some puzzles in cosmic evolution, such as the formation of the singularity and the triggering mechanism of the big bang, the reason of accelerating expansion, the essence of dark energy and gravitational waves. The process of cosmic evolution is a difficult topic. Due to the limitation of technical means, some theories may be vindicated many years later. This expansion collapse theory of universe evolution is presented as a new cosmic evolution theory for all to discuss.Reference:[1] RIES A G, FILIPPENKO A V, CHALLIS P, et al. Observational Evidence from Supernovae for an Accelerating Universe and a Cosmological Constant [J]. Astron. J,1998(116):1009-1038.[2] PERLMUTTER S, ALDERING G, GOLDHABER G, et al. Measurements of Ω and Λ from 42 High-Redshift Supernovae [J]. Astrophys. J,1999(517):565-586.[3] ARK-HAMED N, DIMOPOULOS S, DVALI G. The Hierarchy Problem and New Dimensions at a Millimeter [J]. Phys. Lett. B, 1998(429):263-272. [4] ANTONIADIS I, ARK-HAMED N, DIMOPOULOS S, et al. New Dimensions at a Millimeter to a Fermi and Superstrings at a TeV [J]. Phys. Lett. B, 1998(436):257-263.[5] RANDALL L, SUNDRUM R. An Alternative to Compactification [J]. Phys. Rev. Lett. B, 1999(83):4690-4693.[6] HAWKING S G. Ellis The Large Scale Structure of Space-Time [M]. Cambridge: Cambridge University Press, 1973.[7] CHRISTIANSON G. This Wild Abyss [M]. New York: Macmillan Publishing Co., Inc., 1978.[8] MICHIO Kaku. Parallel worlds [M]. New York: Knopf Doubleday Publishing Group,2004.[9] CHEN Yun. The Theoretical Models of Dark Energy [J]. Astronomy, 2009,29(2)：129-151.[10] TAO Charling. Dark energy observations: Present status and future development [J]. Sci Sin-Phys Mech Astron, 2011, 41(12): 1428-1433 . [11] CHEN Xuelei. Radio Detection of Dark Energy-the Tianlai Project [J]. Sci Sin-Phys Mech Astron, 2011, 41(12): 1358-1366.。

流过半无限竖直可渗透壁面时的磁流体动力学自由对流R.K.辛格;A.K.辛格【期刊名称】《应用数学和力学》【年(卷),期】2012(33)9【摘要】研究不可压缩粘性导电流体,流过半无限竖直可渗透平板时,将其偏微分形式的流动和传热的基本控制方程,应用适当的相似变换,简化为非线性的常微分方程组.对两种抽吸参数:大的和小的抽吸参数,采用摄动法得到变换后方程的近似解.数值结果表明,随着磁场参数和抽吸参数的增大,任意点的速度场在减小;磁场参数的影响,引起热边界层厚度的增大;速度和温度场随着热汇参数的增大而减小.【总页数】14页(P1129-1142)【关键词】磁流体;抽吸;自然对流;Prandtl数;源/汇;渗透;边界层【作者】R.K.辛格;A.K.辛格【作者单位】贝拿勒斯印度教大学数学系【正文语种】中文【中图分类】O357.3;O361.3【相关文献】1.微极流体薄膜层通过以滑移速度移动的可渗透无限平板时流体特性变化和热辐射对流动和热传导的影响[J], M·A·A·哈玛麦德;S·E·瓦希德2.化学反应对流过半无限垂直多孔板的粘性耗散非定常磁流体流动的影响 [J], J.A.饶;S.施崴阿赫3.化学反应对竖直平板边界磁流体动力学微极流体滑流的影响[J], R·C·乔德哈瑞;A·K·吉哈;黄锋(译);张禄坤(校)4.可渗透壁面上Falkner-Skan磁流体动力学流动的近似解 [J], 苏晓红;郑连存5.两种互不相溶流体在竖直的波状壁面和平行的平面壁面间作不稳定的混合对流传热[J], J·C·宇马法士;劉一中;M·舍卡因版权原因，仅展示原文概要，查看原文内容请购买。

美国伟罗里达高磁场实验室落成
爱民
【期刊名称】《高能物理参考资料》
【年(卷),期】1995(000)002
【总页数】4页(P11-14)
【作者】爱民
【作者单位】无
【正文语种】中文
【中图分类】O572.21
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3.梵·高的"鞋"——海德格尔、夏皮罗、德里达之争小议 [J], 贺雅洁
4.美国中佛罗里达大学齐远伟教授受聘为我校客座教授 [J],
5.佛罗里达海洋中心美国弗罗里达州代托纳比奇 [J], 凯文.戈登;Robert Bielamowicz;Brian Gassel
因版权原因，仅展示原文概要，查看原文内容请购买。

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