New D=4 gauged supergravities from N=4 orientifolds with fluxes
新视野大学英语读写教程4Unit1单词和例句
新视野大学英语读写教程4Unit 1 （Section A）1. chase vt. 追逐追赶My dog likes chasing rabbits.我的那条狗喜欢追逐兔子。
2. cruelty n. 残酷残忍The book tells readers the cruelty of the slave trade at that time.这本书告诉了读者在那个时候奴隶买卖的残忍。
3. pessimistic adj. 悲观的The tone of the meeting was very pessimistic.该会议的气氛非常悲观。
The doctors are pessimistic about his chances of recovery.医生们对他康复的可能性感到悲观。
4. conquest [U] 征服控制攻占The conquest of inflation has been the Government’s economic priority.控制通货膨胀一直是政府经济工作的重点。
He finally made the conquest of the disease come true.他最后战胜了那疾病。
The empire had expanded largely through military conquest.帝国的扩张主要是通过军事占领。
5. bankrupt adj. 破产的The company was declared bankrupt.这家公司被宣布破产。
Five years ago she was a successful actress, but now she is bankrupt.五年前她是一个成功的演员，可是现在她一贫如洗了。
6. motive n. 动机Why would she have killed him? She has no motive.她为什么会杀他呢？她没有任何动机。
Continued fraction solution to the Raman interaction of a trapped ultracold ion with two tr
a rXiv:q uant-ph/01285v117D ec2Continued fraction solution to the Raman interaction of a trapped ultracold ion with two traveling wave lasers Mang Feng 1Max-Planck Institute for the Physics of Complex Systems,N ¨o thnitzer Street 38,01187Dresden,Germany 2Laboratory of Magnetic Resonance and Atomic and Molecular Physics,Wuhan Institute of Physics and Mathematics,Academia Sinica,Wuhan 430071People’s Republic of China (February 1,2008)Abstract Raman interaction of a trapped ultracold ion with two traveling wave lasers has been used extensively in the ion trap experiments.We solve this interaction in the absence of the rotating wave approximation by a continued fraction,without considering the restriction of the Lamb-Dicke limit and the weak excitation regime.Some interesting characteristics of the ion-trap sys-tem,particularly for the ion outside the weak excitation regime are found.Finally,a comparison of our results with the solution under the rotating waveapproximation is made.PACS numbers:42.50.DV,32.60.+iTypeset using REVT E XQuantum effects in the motion of trapped ultracold ions have been drawn much attention in recent years since the success that a single ultracold ion was confined in the ground state of a Paul trap[1].Considerable progress has been made so far,such as the preparation and measurement of various nonclassical states[2],and two qubits logic gate operation[3],which are of great current interest in ion trap experiment.It has been proven that a trapped ultracold ion experiencing laser waves can be described by the Jaynes-Cummings model(JCM)[4]under the rotating wave approximation(RWA). The JCM,describing a two-level system coupled to a harmonic oscillator under RWA in the case of near resonance and weak coupling,has successfully dealt with the cavity QED problems,in which a two-level atom interacts with a monochromatic cavity mode with the form of harmonic oscillator.In the trapped ion configuration,the ion is simplified to be two levels and supposed to move within the region of the space much smaller than the effective wavelength of the laser wave(Lamb-Dicke limit),the vibrational level of the trap is quantized as the harmonic oscillator,and the laser radiating the ion is generally supposed as the classical form of a standing or traveling wave.Different from the situation of cavity QED,the strength of the coupling between the ion and the oscillator can be conveniently adjusted simply by changing the intensity of the laser.For example,in the strong excitation regime[5,6,8],the coupling constant,denoted by Rabi frequency,is larger than the trapping frequency,which makes RWA no longer valid.Under RWA,along with the assumption that the ion is confined within the Lamb-Dicke limit(LDL)and weak excitation regime(i.e.,the Rabi frequency being smaller than the trapping frequency),one may easily obtain three simple cases[4,6],that is,carrier excitation, red detuning and blue detuning.If excluding the supposition with respect to the LDL and weak excitation regime,Vogel and his coworkers gave a standard approach to such a nonlinear JC model[7].However,in case the RWA is excluded,the ion trap problem turns to be non-integrable,whose solutions have to be obtained completely by the numerical calculation[6,8]. Recently,we analytically treated[9]the interaction in the absence of RWA between a standing wave laser and a trapped ultracold ion in coherent state representation[10,11].Althoughthose analytical results are only some particular solutions to the problem,some important information neglected in former works due to use of RWA were presented.However,our investigation in that work was only under both the weak excitation regime and the LDL. Moreover,the solutions in that work strongly depended on the truncation of the series, and thereby the deduction and the forms of the analytical expressions went tedious with the increase of the number of terms in the series,which makes it hard to obtain the eigenenergies and eigenfunctions rapidly at our disposal.Furthermore,it is Raman configurations that are usually applied in actual ion trap experiments for the interaction between lasers and ions,instead of the simple case described in Ref.[9].Therefore,in this contribution,we choose RamanΛ-type configuration(shown in Fig.1)for a study,which corresponds to the actual process in the NIST experiments[1].To present a more general description for such a model,we will exclude the assumption related to both the weak excitation regime and LDL by means of some unitary transformations.Moreover,to overcome the difficulty of complicated analytical deduction,our solution will resort to a continued fraction,from which the eigenenergies of the system and the coefficients of the series of the eigenfunctions can be rapidly obtained by numerical calculation.Fig.1describes the interaction of a trapped ultracold ion with two off-resonant counter-propagating traveling wave lasers with frequenciesω1andω2respectively.Both laser beams are assumed to propagate along the x axis,and the problem is thereby one-dimensional. For a sufficiently large detuningδ,the third level|r>may be adiabatically eliminated,and we face an effective two-level system,in which the lasers drive the electric-dipole forbidden transition|g>↔|e>.In the frame rotating with the effective laser frequencyωL(=ω1−ω2), the dimensionless Hamiltonian of this system is[1,2,12]H=∆2(σ+e iηˆx+σ−e−iηˆx)(1)where∆=(ω0−ωL)/νwithω0being the resonant frequency of the two levels of the ion,andνbeing the trap frequency.Ωis the dimensionless Rabi frequency andηthe Lamb-Dicke parameter.σi(i=±,z)are Pauli operators,ˆx=a++a is the dimensionlessposition operator of the ion with a+and a being operators of creation and annihilation of the phononfield,respectively.The notations’+’and’-’in front of iηˆx indicate that the laser wave propagates towards x and-x directions,respectively.νis generally supposed to be much greater than the atomic decay rate(strong confinement limit)for neglecting the effect of the atomic decay.Wefirst perform some unitary transformations on Eq.(1)[12],and obtainH I=UHU+=Ω√dα,and rewrite Eq.(2)in coherent state representation,that is,H=Ωdα+g(α+d2πiexp(−|α|2)|α∗><α∗|=1.The eigenfunctionof the Schr¨o dinger equation of Eq.(3)can be supposed to beΨ(α)= Ψ1(α)Ψ2(α) ,and the eigenenergy is E.Thus we have(α+g)d2Φ2,(4)(α−g)d2Φ1(5)where we have made a transformationΦ1=Ψ1(α)+Ψ2(α)andΦ2=Ψ1(α)−Ψ2(α).To solve Eqs.(4)and(5),we orderξ=α+g,andΦ1=exp(−gξ)φ(ξ).Combining Eq.(4)with Eq.(5)will yield a second-order differential equationξ(ξ−2g)d2dξφ+[E2−ǫ2−Ω2By supposingφto be a series formφ= ∞n=0C nξn,Eq.(6)becomes a recurrence relation about the coefficient C nαn C n+1+βn C n+γn C n−1=0(7) whereαn=2g(n+1)(E−ǫ−1−n),βn=[n2+2n(2g2−E)+E2−ǫ2−Ω2βn−1−γn−1αn−2β1−γ1α0/β0=αnγn+1βn+2−αn+2γn+32σz+αdΩ2detunings.In view of physics,the only reasonable explanation for this case is that the in-teraction between the laser and the ion plays main role in the system.With the increase of the detuning,this interaction goes weaker and weaker.Therefore,although the energy of the ion itself is enhanced with the increase ofη,the energy of the total system remains nearly constant;(iii)Fig.4presents the relation betweenΩand∆for certain values of E andη.From the forms of the curves,we may guess that the relation among E,∆,ηandΩis of the form of Ω=f(E)[1−h(η)∆2]with f(E)and h(η)being positive definition functions of E andη, respectively.Moreover,from the specific calculation,we found that,for a certainΩ,with the increase ofη,the convergence of C n would get worse and worse,particularly for the large detuning case.But the larger the value ofΩ,the larger the value ofηfor satisfying the convergence of C n.The problem with respect to the convergence will be discussed physically later.Returning Eqs.(4)and(5),we canfind thatΦ1=exp(gξ)φis another solution for ξ=α+g.Repeating above deduction,we will obtain Eq.(8),whereas in this case,αn= 2g(n+1)(E−1−ǫ−n),βn=(n2−2nE−4ng2+E2−ǫ2−Ω2Ω ∞n=0(n−E+ǫ)C n(α+g)n e±g(α+g).Therefore,the eigenfunction of the system isΨ(α)= Ψ1(α)Ψ2(α) =1Ω(n−E+ǫ)](α+g)n∞n=0C n[1+2|n>= dαdα∗√2σz+αd2 AB∞n=0C nαn(11)where A=1±2Ω2Ω,B=1∓2Ω2Ω.Then the eigenfunction in theoriginal representation isΨSO(α)=12e iπa+a/2 11−11 1√Ω±2Ω2presented the solutions in the weak excitation regime for the case of near-resonance.In our treatment,however,the numerical solution is made based on the continued fraction,which is obtained in the coherent state representation.So our solution is still valid even for the large detuning and strong excitation regime.Before ending our discussion,it is interesting to make a comparison between our solution with those under RWA.In general,we may solve Eq.(1)by means of nonlinear JC model as proposed in[7]for the ion governed outside the weak excitation regime.However,to make the comparison easily and obviously,we start our comparison procedure from Eq.(2).By)t]on Eq.(2),we can obtain E±n= performing a unitary transformation exp[−i(Ω22n+1η2±14η2(n+1)+1(n=0,1,2,···)in the Fock state representation forΩ=2 4under RWA(see Figs.8).From Figs.3,6and8,we see that,for small values ofη,the case of n=2under RWA is similar to those ofΩ=2in Figs.3and6,where E+n and E−n are similar respectively to the very large and zero detuning cases without RWA.Although both the solutions with RWA and without RWA include multi-curve,the difference is obvious:as it is merely a particular solution,the solution without RWA approaches to the solution of a certain excited state under RWA.On the other hand,as RWA merely retains some resonance terms in Hamiltonian,the solution under RWA is irrelative to the variation of∆and just related to a specific value ofΩ.Moreover,as they are obtained from the solution of Eq.(8), the results without RWA are restricted by the convergence of the coefficients of the series.In contrast,there is no restriction mathematically for the expressions of the solution under RWA even in the case ofη→∞.However,in physics,ηis impossible to approach to infinity for a ultracold ion system,and it must be cut offat a certain value.Therefore,in this sense,the convergence condition in our solution of the continued fraction provides a physical restriction on thefinal results,which plays the same role as the restricted condition for the solutions in)t]and Ref.[9].Furthermore,further deduction with the transformations exp[−i(Ω4exp[−i(Ω)t]performed on Eq.(2)respectively can tell us that,with the increase of 6Ωandη,the difference between the solutions with RWA and without RWA will be larger and larger.In summary,we have presented a continued fraction solution to a trapped and laser-radiated ultracold ion experiencing two traveling wave lasers in a Raman process in the absence of RWA.Instead of the complicated and tedious analytical forms in Ref.[9],we can solve the problem rapidly from the continued fraction and present more complete information of the system,such as the relation among E,Ω,∆andη.As limitation of weak excitation regime and LDL as well as RWA is excluded in our treatment,our solution is not only exact, but more general.It can be used to investigate quantum properties of the ion-trap system in a wider range of parameters,and serve as a comparison with other approximate works, as we did in Ref.[16].However,as Eq.(2)represents a kind of typical non-integrable system, our solutions are still only some particular ones.While in comparison with former solutions under RWA,we still found some interesting results,particularly for the case outside the weak excitation regime and LDL.We should emphasize that,it is hard to carry out the trapped ion-laser interaction experimentally outside the weak excitation regime at present due to the requirement of very high intensity of the laser,and the laser cooling to the ground state of the trapping potential has not been reported yet in this regime.Therefore,we hope the solution in our work would be helpful for the future exploration of the quantum properties of the ion-trap system in this respect.The work is partly supported by National Natural Science Foundation of China under Grant No.19904013.Note added:after accomplishing this paper,the author becomes aware of that a work[17] related to the fast quantum gate for cold trapped ions has been carried out based on Ref.[12] and the treatment similar to our RWA treatment.REFERENCES[1]Diedrich F,Bergquist J C,Itano W M,and Wineland D J,Phys.Rev.Lett.62(1989)403;Monroe C,King B E,Jefferts S R,Itano W M,Wineland D J,Goulkd P,Phys.Rev.Lett.75(1995)4011.[2]Meekhof D M,Monroe C,King B E,Itano W M,Wineland D J,Phys.Rev.Lett.76(1996)1796;Monroe C,Meekhof D M,King B E and Wineland D J,Science, 272(1996)1131.[3]Monroe C,Meekhof D M,King B E,Itano W M,Wineland D J,Phys.Rev.Lett.75(1995)4714.[4]Jaynes E T and Cummings F W,Proc.IEEE,51(1963)89;Blockley C A,Walls D F,Risken H,Europhys.Lett.17(1992)509;Cirac J I,Parkins A S,Blatt R,and Zoller P, Phys.Rev.Lett.70(1993)556;mun.97(1993)353;Cirac J I,Blatt R,Parkins A S,and Zoller P,Phys.Rev.Lett.70(1993)762.[5]Poyatos J F,Cirac J I,Blatt R and Zoller P,Phys.Rev.A54(1996)1532.[6]Cirac J I,Parkins A S,Blatt R,and Zoller P,Adv.Atom.Mole.Opti.Phys.V37(1996)237.[7]Vogel W and Filho R L de M,Phys.Rev.A52(1995)4214;Filho R L de M and VogelW,Phys.Rev.Lett.,76(1996)608.[8]Zeng H,Lin F,Wang Y and Segawa Y,Phys.Rev.A59(1999)4589.[9]Feng M,Zhu X,Fang X,Yan M and Shi L,J.Phys.B32(1999)701.[10]Negele J W and Orland H,Quantum Many-Particle Systems(Addison-Wesley,Reading,1987)20.[11]Ku`s M and Lewenstein M,J.Phys.A19(1986)305.[12]Moya-Cessa H,Vidiella-Barranco A,Roversi J A,Freitas D S and Dutra S M,Phys.Rev.A59(1999)2518[13]Feng M,Fang X,Duan Y,Zhu X,and Shi L,Phys.Lett.A244(1998)18.[14]Plata J and Llorente J M G,Phys.Rev.A48(1993)782.[15]Feng M,Fang X,Shi L,Zhu X and Yan M,Commun.Theor.Phys.31(1999)175.[16]Qin G,Wang K,Li T,Han R and Feng M,Phys.Lett.A239(1998)272.[17]Jonathan D,Plenio M B and Knight P L,Phys.Rev.A62,(2000)042307Captions of thefiguresFig.1Level scheme of the internal structure of the trapped ultracold ion,where|g>↔|e>is dipole forbidden.Fig.2Variation of E with respect to∆in the case ofΦ1=exp(−gξ)φ,where the dotted,dashed,solid and dash-dotted curves representη=0.2,0.4,0.6and0.8,respectively. For clarity of thefigure,we only plot the cases forΩ=2,4and6.Fig.3Variation of E with respect toηin the case ofΦ1=exp(−gξ)φ,where the solid, dotted,dash-dotted and dashed curves represent∆=0.2,1.6,2.0and3.0,respectively.For clarity of thefigure,we only plot the cases forΩ=2,4and6.Fig.4Variation ofΩwith respect to∆in the case ofΦ1=exp(−gξ)φ,where the solid, dashed and dotted curves representη=0.02,0.4and0.6,respectively.We only plot the cases for E=3and5.Fig.5Variation of E with respect to∆in the case ofΦ1=exp(gξ)φ.The rest are the same as that in Fig.2.Fig.6Variation of E with respect toηin the case ofΦ1=exp(gξ)φ.The rest are the same as that in Fig.3.Fig.7Variation ofΩwith respect to∆in the case ofΦ1=exp(gξ)φ.The rest are the same as that in Fig.4.Fig.8Variation of E±n with respect toηforΩ=2for the solution under RWA.See text.11|r>δ2ω1ωω∆Fig.1|e>|g>。
新视野大学英语4 第三版读写教程 第二单元答案(B4U2)
1. How do you understand the sentence "No amount of rehearsal will help you come up with the right answer" (Para. 2)?Reference:The sentence means that it is very difficult, or even impossible, for a man to give a right answer when a woman asks him how she looks, no matter how hard he thinks about it and how many different answers he tries.2. According to the text, in what way do men and women evaluate their appearance differently?Reference:Men are satisfied with being average-looking, paying little attention to their looks. In contrast, women pay great attention to their body and image, considering their appearance as not good enough even if they are in fact attractive.3. What causes women to be always dissatisfied with their looks?Reference:The interaction of many psychological and societal factors, for example, their childhood experiences with toys, and the influence of the media.4. In what way do the toys girls play with differ from those boys play with?Reference:Girls' toys are proportioned to have extreme measures of the body (e.g. in terms of height, weight and waist size), whereas boys' toys can look weird rather than handsome.5. What does the sentence "You could not imagine him saying to the others, ‘Is this accessory the right shade of violet for this outfit?'" (Para. 6) imply?Reference:It implies that men pay little attention to the details of their appearance.6. Why is the supermodel Cindy Crawford mentioned in Paragraph 7?Reference:Cindy Crawford is mentioned as an example to show that the beauty industry and the media have great influence on women's devotion to physical beauty and the use of beauty products.7. What is the author's attitude toward the claim that women care much about their appearance due to pressure from men?Reference:The author thinks that the claim is not right since men in fact pay little attention to the details of women's appearance.8. Why do women think that men are not qualified to judge whether a woman looks good or not?Reference:Women think so because men do not even care about their own appearance. For instance, a man often does not bother to clean the cream in his hair or ears after shaving.1. What are the factors that make women pay much greater attention to their appearance than do men?Reference:I think there are three main factors accounting for women's greater attention to appearance. The first are cultural traditions. It is common in many cultures that people put high value on beauty when they look at women. The second is the requirement of certain jobs. For example, in China airline companies set certain criteria for appearance (e.g. in terms of height and weight) when they recruit stewards and stewardesses. Finally, the influence of the media is another strong factor which shapes women's pursuit of physical beauty. There are a lot of advertisements of cosmetics and skincare products in various media such as TV, magazines and newspapers. They often havecelebrities as the spokesperson for the advertised products, which makes women have an illusion that they could look as good as those famous stars if they use the products. In short, these three factors exert immense influence on how women value appearance.2. Are there any occasions in life where it is necessary for a person, either a woman or a man, to look good? Why or why not?Reference:• Yes. On certain formal occasions, a person, either female or male, has to pay attention to his attire. Sample cases are job interviews, business meetings, weddings, and banquets. This is because to dress properly is an important element of successful completion of these events.• No. People do not have to care what others think of them as long as they feel comfortable and satisfied with their looks themselves. After all, this is the most important source of happiness to people.3. What do you consider as the most important traits that make a person beautiful?Reference:In my opinion, the important traits of human beauty include two types, one for appearance and one for inner qualities. Features that characterize a beautiful appearance are a good-looking body, proper clothes and accessories, as well as use of makeup that matches the occasion or event one is attending. Inner qualities that make a person beautiful mainly include good manners and positive personality traits such as honesty, bravery or friendliness.4. What do you think of the relationship between wearing makeup and female beauty? In other words, do women have to apply cosmetics in order to look beautiful? Why or why not?Reference:• Yes. Women should pay great attention to their appearance and hence need to wear makeup. This is because beauty is, believe it or not, usually an important quality for women to succeed, for example, when they want to look for a job or an ideal husband.• No. What really makes a person beautiful is inner beauty rather than physical appearance. A beautiful look can't last long, but inner beauty, for example, intelligence and honesty, may make a person successful and happy throughout his life.5. If you were the head of a cosmetics company, how would you market or promote a new product?Reference:I would market a new product by three means. First, I can ask a celebrity, for example a famous movie star or a supermodel, to be the brand spokesperson on TV. This is a common practice in the advertising industry, and I think it is very effective. Second, I will hire people to distribute flyers and give away free samples of the product on the streets, so the product can reach potential customers directly. In addition, I may post advertisements on public transportation vehicles such as buses and subways. In this way, the commercials can be seen by a large number of people.Fill in the blanks with the words given below. Change the form where necessary. Each word can be used only once.Done with this activity. Time submitted: 2017-03-07 21:43 (Tuesday)Your score: 0%1.We need to improve the quality of education so that our children willnot leave school (deficient)in literary and reasoning skills.2.In a society governed by the rule of law, every citizen is subjectto possible (prosecution)if he violates the law.3.The pay gap between average workers and top corporate officers hasled to pubic (outrage)as executives receive large packages despite falling share prices.4.The delicious meal (appeased)our hunger and made us feel warmagain after having walked in the snow all day.5.The military insists on (conformity)in many areas, forexample, dress and haircut, with the primary objective of promoting group unity.6.My daughter used to play with the dog by taking a(n)(strand)of its hair and then spending a long time rubbing, combing and twisting it.7.When she left for the party, she took great care to make her necklaceand shoes (complement)her dress.8.It was necessary to provide living places for(transient)immigrants passing through the area on their way to more permanent dwellings.9.They had just moved in, so they needed to buy a number of kitchen(appliances), including a microwave oven, a toaster, and a coffee maker.10.She wanted a beautiful and elegant (outfit)to attend thewedding of a friend, but couldn't find anything satisfactory in the nearby shops.Add-ion,-er,or-ist to or remove them from the following words to form new words.For each blank you can only fill in one word.Correct answerdominationorientationconfrontationcomposerbinderscannermanufacturereraseimperialistleftistterroristhumanistFill in the blanks with the newly formed words. Change the form where necessary. Each word can be used only once.1. The Internet challenges the (domination) of traditional media such asnewspapers and television as the main sources of news in modern society.2. Some scientists warn that the X-ray (scanners) now being used toscreen passengers at many airports may be harmful to the human body.3. Many people think that a(n) (humanist) should have very strongmorals, in addition to beliefs in a philosophy that focuses on human values and concerns.4. The police interviewed all six witnesses, but none of them could describeclearly how the (confrontation) began and who opened fire first.5. In politics, (leftists) are people who generally support social changesto create a more equal society and show concern for those who sufferdisadvantages.6. A study of mid-level administrators' career (orientation) showed thatmany of these managers view their current position as a temporary step on an upward path.7. The idea that the United States is a melting pot implies that racialdifferences are to be (erased)and that immigrants should give up their own cultural traditions.8. Effective measures should be taken to prevent (terrorists) fromattacking civilians, people who have no power to defend themselves from bombs and guns.9. Toyota is one of the world's largest (manufacturers) of cars, withmore than 50 plants across the globe outside Japan.10. He sent his parents some of his recent news articles in a(n) (binder) ,arranged according to their publication dates.11. This island became a colony after European (imperialists) decided touse it as their trading port in the 19th century.12. The concert to be held next month promotes music by(composers) from Africa and South America.Drag 10 words from the list to their proper places to complete the passage. Each word can be used only once.Double click on a particular blank to reset it if necessary.I was once in a relationship with a woman who was the most brilliant, creative and driven person I'd ever known. I told her these things often because she didn't see herself this way, despite (1)(achieving) great success and acclaim (称赞) in her professional field. She was also (2)(gorgeous) and sexy, though she seemed not to realize this either, so I told her these things too. But while I thought it was more important to praise her brilliance, it seemed to mean more to her that she was (3)(considered) attractive.My experience with this girlfriend exemplifies a common phenomenon in life —when it comes to complimenting a woman, men often walk a very difficult line. Of course, (4)(context)matters. In a professional setting, talking about appearance is often inappropriate, but at a singles club, it may be important. She will be very pleased if a man thinks her clothes and (5)(accessories) are pretty, or her hair looks wonderful. However, things inbetween these two cases are unclear. Women have every right to be recognized and (6)(appreciated) for their intelligence and creativity. But at the same time, they want to be admired for their looks as well, for example, their perfect skin (7)(complexion) and elegant outfits.Unfortunately, most guys don't understand this. If we receive compliments from women, they're usually about our achievements, not our looks. Most of us don't expect a woman to tell us how (8)(handsome) or sexy we are, and some of us would find it hard to regard such a(n) (9)(comment) as sincere. I'm not saying it's very hard to be a guy these days. It is important for every man to understand how to treat women with both respect and (10) (admiration). But as far as the right balance of these two is concerned, we really have no frame of reference, especially when it comes to looks.Fill in the blanks with the expressions given below. Change the form where necessary. Each expression can be used only once.1. Every month, the Community Services Center offers several lectures onhealth and fitness (in hopes of) introducing people to healthierlifestyles.2. Do you know who (came up with) the idea of having cheesecake fordessert yesterday? It was delicious and made everyone happy.3. The pain medication left Claudia feeling rather dull and sleepy, and soonafter dinner she apologized for being such poor company and(excused herself) to bed.4. When I was young, I (was obsessed with) maps, and I sometimesspent the whole day charting land routes from one point to another.5. To make immigrants comfortable (reaching out to) police for help,more than 70 cities now bar police from asking them to prove their legal status.6. Mary was often accused of "having a strong personality" because she wasnot afraid to (voice an opinion on) subjects about which she wasknowledgeable.7. At the end of his term in office, the governor was criticized for failure to(live up to) his campaign promise.8. Results of a survey revealed that of the top 10 automobile makers (interms of) customer satisfaction, six were Japanese and two wereGerman.Write a contrast essay of no less than 200 words on the topic "How do women and men groom themselves?". You can follow the outline given below.Done with this activity. Time submitted: 2017-03-07 21:53 (Tuesday) Outline:How do women and men groom themselves?Women and men take care of their appearance in very different ways, which are mainly shown in three areas.• The variety of beauty tools and products they use• The amount of clothes they have• The amount of time they spend on grooming themselvesWomen and men behave differently in how they attend to their routinegrooming chores.My writing:When you get yourself ready to go to school or work in the morning, or attend a party in the evening, you may have to do various preparations. What youconsider as essential to prepare largely depends on whether you are a female or a male. Women and men take care of their appearance in different ways, which are mainly shown in three areas.One difference lies in the variety of beauty products that women and men use. Women have a great variety of tools and skincare products; for example, combs and clips for hair, brushes for powder foundation, and eyeliners for eyebrows, creams for face, to name just a few. Men, however, do not use so many things. They may comb their hair, but they seldom use cosmetics. Another difference involves the amount of clothes women and men have. Females usually have many more clothes than men do. You may well be familiar with movie scenes in which a woman tries on the outfits in her wardrobe one after another and still hesitates about which one to wear. Unlike females, males do not buy themselves piles of clothes as long as they still have something at home.The third difference is that women spend much more time grooming themselves than men do. It can easily take a woman half an hour or even several hours to get a perfect hair style or apply makeup to her face. In contrast, it may just take a man several minutes to tidy himself. All he needs to do is to comb his hair and put on whatever clothes he finds in the drawer.To conclude, women and men behave differently in how they attend to their routine grooming chores. Such distinctions help create the typical images of females and males in human society.Translate the following paragraph into Chinese.Done with this activity. Time submitted: 2017-03-07 21:53 (Tuesday) The originalWilliam Shakespeare is widely regarded as the greatest writer in the English language and the world's pre-eminent (杰出的) dramatist. His plays have been translated into a vast number of languages and are performed more often than those of any other playwright. Shakespeare's early works were mostly comedies and histories, which have the reputation of being among the finestmasterpieces produced in these genres (体裁) even today. Later on, Shakespeare wrote mainly tragedies, some of which, like Hamlet and King Lear, earned him fame in the entire Western literature. The most striking features of Shakespeare are his brilliant use of language and his universal themes. He contributed thousands of words to English, many of which have become embedded in the language. His themes are so universal that they transcend generations to stir the imaginations of readers and audiences worldwide. Shakespeare has influenced and inspired many writers over the centuries. His writings remain highly popular today, and they are constantly studied, performed, and reinterpreted in diverse cultures throughout the world. Shakespeare will continue to have an enormous impact on future playwrights, novelists, poets, actors, and scholars.My translation人们普遍认为，威廉•莎士比亚是最伟大的英语作家和世界杰出的戏剧家。
新探索研究生英语(提高级)unit4
新探索研究生英语(提高级)unit4Title: New Explorations in Research on Graduate English (Advanced Level) Unit 4In Unit 4 of the New Explorations in Research on Graduate English (Advanced Level), students delve deep into the topic of academic writing. This unit focuses on honing the skills necessary for producing high-quality research papers, essays, and other academic texts. It also covers important concepts such as thesis statements, organization, coherence, and citation.One of the key objectives of Unit 4 is to help students understand the structure of academic writing. This includes learning how to create a strong thesis statement that clearly outlines the main argument of the paper. Students also explore different organizational techniques that can help them present their ideas in a logical and coherent manner.Another important aspect of Unit 4 is citation and referencing. Students are taught the importance of giving credit to other scholars and researchers by properly citing their work. They learn how to use different citation styles, such as APA, MLA, and Chicago, and practice incorporating sources into their own writing effectively.Moreover, Unit 4 encourages students to engage critically with the literature on their chosen topic. They learn how to evaluate sources for credibility, relevance, and bias, and how to synthesize information from multiple sources to develop their own arguments.Overall, Unit 4 of the New Explorations in Research on Graduate English (Advanced Level) provides students with the tools and strategies needed to excel in academic writing. By mastering the skills covered in this unit, students will bewell-equipped to produce high-quality research papers and essays that contribute meaningfully to their field of study.。
人教_高一英语必修四_Unit4_单元主题素养阅读
Unit4 单元主题素养阅读时事阅读阅读提示：根据美国之音报道,谷歌公司给予创造了Apgar测试的医生极大|的荣誉。
这位医生是谁? Apgar测试的意义何在?This is What's Trending Today.The search engine Google is honoring the life of an American doctor who developed a system for measuring a newborn baby's health.Virginia Apgar is the subject of the Google home page's latest Doodle. Thursday would have been Apgar’s 109th birthday.As Google explains，Apgar，s presence can still be felt in delivery rooms across the globe.As a medical student，Apgar noted that a number of babies that had seemed healthy at birth were dying soon after leaving the hospital. This was because there was no commonly used method for measuring newborn health.In 1952，she created a life-saving test. This five-step test has doctors examine the appearance, pulse, grimace (怪相)，activity, and breath of newborns. The test is easy to remember. The first letter of each step spells Apgar ：A-P-G-A-R.Doctors score each part score of zero to two，with the highest total score being 10. They examine the newborns one minute after birth and then again five minutes after birth. The scores help doctors identify whether a baby has health issues requiring extra care.The APGAR test soon spread in America and around the world. It is still widely used today.Apgar9s life included many other successes. In 1949，she became the first woman to be named a full professor at the medical school she attended, Columbia University、College of Physicians and Surgeons, in New York City.Later，she led the birth defects department at the organization known today as the March of Dimes.Thursday’s Google Doodle appeared for internet users in the United States, as well as Japan，India, Israel, Chile, Argentina, Australia and several European nations.Apgar was born on June 7，1909. She died in 1974 at the age of 65.In 1995, she was admitted into the National Women’s Hall of Fame.And that’s What’s Trending Today.I’m Caty Weaver.1.Why is Virginia Apgar being honored by the search engine Google?A.Because she was admitted into the. National Women’s Hall of Fame.B.Because she was named a full professor at the medical school.C.Because she developed a system for measuring a newborn baby’s health.D.Because she examined the newborns one minute after birth.2.What happened to many newborn babys after they left the hospital?A.They were dying soon.B.They got APGAR test.C.They seemed healthy.D.They required extra care.答案1. C2. A经典阅读阅读提示：《杀死一只知更鸟》是由美国女作家哈珀·李所创作的长篇小说。
新版新视野大学英语读写教程第四册unit4答案
work at home rather than go to the office.
3. Some people sayபைடு நூலகம்that the pupils' achievements this term will be measured by a formal test rather
than their teacher's assessment.
4. They argued that their products should be developed on the basis of need rather than profit.
5. During weekends the businessmen may spend time establishing friendship and mutual trust rather
VIII.
1. auto-timer 2. auto-focus 3. autograph 4. auto-reverse
5. autobiography 6. automakers 7. autoloading 8. autocriticism
sentence structure
IX
1. Concentrate on indoor delights rather than outdoor fights and you'll be much better appreciated.
the two. Under the new welfare system, the law encourages welfare clients to work on their own for a
人教版高中英语选择性必修第四册unit1复习课件
2. They bought ten computers last term．
Ten computers were bought (by them) last term. 一般过去时：S+was/were +过去分词
五、何时使用被动语态呢？
一、行为主体不明确，不必说出或者无 法说出动作的执行者时。例如：
Football is played all over the world．
二、不易找到或根本就不可能找到动作 的执行者时。例如：
My bike was stolen．我的自行车被盗了。
三、汉语中含有“据说”、“据悉”、“有 人说”、“大家说”等时。例如：
Some country music was played for us.
31
七、 被动语态的几个问ቤተ መጻሕፍቲ ባይዱ： 3. 带复合宾语的动词的被动结构
例：His father called him Jack. He was called Jack by his father.
带复合宾语的动词变被动语态时, 一般将主动结 构中的宾语变为被动结构中的主语, 而将宾语补 足语保留不动(这时的宾语补足语为主语补足语)。
七、 被动语态的几个问题：
有些不及物动词主动形式可表被动意义
例：It can’t move. The door won’t shut.
7. 某些与 can’t, won’t 等连用的不及物动词， 如move, lock, shut, open等。
七、 被动语态的几个问题：
人教版选择性必修四Unit1ScienceFiction知识清单
[练透]—单句语法填空
12.We declare________garbage-sorting in new efforts to better protect the environment. (用适当的词填空)
【答案】for
【解析】
【详解】考查固定搭配。句意：为了更好地保护环境，我们支持进行垃圾分类。根据句意和空格前的动词declare可知，此处是考查declare和介词for的搭配declare for“表明赞成（拥护）”。故填for。
【解析】
【详解】考查名词。句意：一旦你预约了，你就应该遵守，而不是违背。结合句意及空前 made an可知，应填名词形式appointment，做宾语，短语make an appointment意为“预约；约会；预约时间；约定”，固定搭配。故填appointment。
9.I was appointed________(take) charge of arranging all the activities on that day. (所给词的适当形式填空)
6.explode vi.& vt.爆炸；爆破→________n.爆炸；爆破（声）→________adj.易爆炸的；猛增的
7.mud n.泥；泥浆→________adj.泥泞的
【答案】1. ①.appointment②.appointed
2.guilty3.weekly
4.declaratiຫໍສະໝຸດ n11．gripvt.&vi.紧握;抓紧
12．hazyadj.模糊的;朦胧的;困惑的
13．joltn．震动;摇晃;颠簸vt.&vi.(使)震动;摇晃
14．flipvt.&vi.(使)快速翻转;(用手指)轻抛
Remodeling the Pentagon After the Events of 22306
a r X i v :h e p -p h /0606313v 1 29 J u n 2006Preprint typeset in JHEP style.-PAPER VERSIONT.Banks Department of Physics University of California,Santa Cruz,CA 95064E-mail:banks@ and NHETC,Rutgers University Piscataway,NJ 08540Abstract:The meta-stable SUSY breaking mechanism of Intriligator Seiberg and Shih can be used to simplify the Pentagon model of TeV scale physics.The simplified model has only a single scalar field and no troublesome low energy axion.One signif-icant signature is l +l −X plus missing energy,where X might be the two photons of gauge mediated models,but is likely to be different.There is a new strongly interacting sector with a scale around 1.5TeV.The penta-hadrons of this sector have masses of order 6TeV or more.Dark matter is probably the pseudo-goldstone boson of sponta-neously broken penta-baryon number.This can be a viable dark matter candidate if an appropriate asymmetry in penta-baryon number is generated in the early universe.The pseudo-Goldstone particle has a mass of ∼1eV and is produced predominantly in flavor changing charged current decays of ordinary particles.The model solves the flavor problems of SUSY,but has two low energy CP violating phases,whose value is strongly constrained by experiment.Keywords:Cosmological SUSY Breaking.1.IntroductionIn a recent paper[1],I proposed an explicit model,which implemented the idea of Cos-mological SUSY Breaking(CSB).Apart from thefields of the supersymmetric standard model(SSM),the model consisted of the Pentagon-a new strongly interacting SU(5) super-QCD with5flavors of penta-quark,and three singletfields,S,G,T with a variety of Yukawa couplings to the Pentagon and the SSM.The intricate pattern of singlets was required to motivate the possibility of a meta-stable SUSY breaking vacuum state of theflat space quantumfield theory.It also caused a potential phenomenological problem-a low scale QCD axion.One could invoke higher dimension operators,which raised the axion mass and made it barely compatible with observation.This of course1removed the model’s solution of the strong CP problem.It also introduced afine tun-ing of the electroweak scale,of order1%.This was required to raise the axion decay constant above the laboratory bounds.The Pentagon Paper was written before the world changed on02/23/06.The Neo-conservative1revolution in SUSY breaking,heralded by the paper of Intriligator, Seiberg,and Shih(ISS)[3]now provides us with a plethora of calculable SUSY breaking models,where SUSY is broken in a meta-stable state-exactly what is needed to solve the problems at the Pentagon.ISS prove that when a mass term m ISS tr P˜P is added to SUSY QCD with N C+1≤N F≤3N C4m P1This term is motivated by the fact,pointed out to the author by N.Seiberg,that meta-stable SUSY breaking was advocated in unpublished work by M.Dine,which was done in the run-up to the Affleck Dine Seiberg[2]discovery of models of dynamical SUSY breaking.2rapid deployment to solve all2of the problems of the supersymmetric standard model. It involves a single scalarfield S with discrete R charge2.The only marginal/relevant couplings of S are encoded in a superpotential:W S=g S SP A i P j A Y i j+gµSH u H d+g T S3.Y is the unique traceless SU(1,2,3)invariant matrix in the fundamental representation of SU(5).Note that the SU(1,2,3)standard model gauge group is embedded in the obvious fashion into the vector SU(5)flavor group of the Pentagon.In fact,we could consider a more general version of the model in which we require only that the linear combination of penta-quark bilinears to which S couples,is linearly independent of the combination to which m ISS couples.The form we have written may have a group theoretic justification at the unification scale,which we will discuss below.2.Known knownsThe full low energy Lagrangian of our model isL=d4θ[P∗e V P+Q∗e V Q+L∗e V L+(¯U)∗e V¯U+(¯D)∗e V¯D+(¯E)∗e V¯E]+[ d2θ(( τi W iα)2+P A i˜P j A(m ISSδi j+g S SY i j)+gµSH u H d+g T S31+H u Q m(λu)m n¯U n+H d Q m(λd)m n¯D n+H d L m(λL)m n¯E n+2As is conventional in communications from the Pentagon,we are here indulging in a bit of hyper-bole.3The parameter m ISS is assumed to be induced by Cosmological SUSY Breaking ,CSB,as in[4].The c.c.,λis a tunable parameter3,and m ISS scales likeλ1/4as λ→0.In this limit,the low energy Lagrangian has an U(1)R symmetry,which has no SU P(5)anomaly.P and˜P have R charge zero.A discrete Z4subgroup of this U(1) is assumed to be an exact symmetry of the S-matrix whenλ=0.S has R charge2. The R transformation properties of the SSM chiral multiplets can be chosen so that the only perturbative baryon or lepton number violating interaction of dimension≤5 is the neutrino see-saw term,d2θ(H u L m)(H u L n)S mn3Actually it is discretely tunable.π(RM P)2is the logarithm of an integer number of states.R is the dS radius.In a more ambitious model based on holographic cosmology,one gets a distribution of asymptotically dS universes with differentλ,andλcan be anthropically selected.However,this model has no other testable consequences once the value ofλis chosen,so there is no point in discussing it here.4were not under analytic control.That state had a non-vanishing expectation value for the penta-baryon number violating operators<ǫA1...A N C P i1A1...P i N CA NC>=ΛN C NCǫi1...i N C,<ǫA1...A N C ˜P A1i1...˜P A N Ci NC>=ΛN C NCǫi1...i N C.By contrast,the meson operators P A i˜P j A have vanishing expectation value in this state.This model is merged with the hypothesis of CSB by making two assumptions. First the parameter m is determined so that the gravitino mass at the meta-stable SUSY violating vacuum is given by the CSB formulam3/2=γλ1/4(M p/m P),where M P=√Λ5.Note that this is a term in the Lagrangian at a scale≫Λ5where the Pentagon interac-tions are weak.From the point of view of standard effectivefield theory,it is extremely peculiar to have the IR scaleΛ5appear in the denominator of this parameter.However, the diagrams contributing to the argument for the CSB formula that I presented in[4], combine infrared propagation in a single horizon volume,with UV dynamics in the vicinity of the horizon.It is plausible that they contain such inverse IR scales.The second input from CSB is that we add a constant W0to the superpotential to tune the c.c.at the meta-stable minimum toλ.Again,there is no reason to do this in effectivefield theory,though in this case it would be the strategy of any effectivefield theorist who wanted the meta-stable vacuum to be of phenomenological relevance.The logic for adding W0in CSB is different.λis viewed as a high energy input parameter determined by the number of quantum states in the asymptotic de Sitter space to which the system is converging.It cannot be renormalized,and the constants in effectivefield theory must be tuned to reproduce its input value.It should be emphasized that from the point of view of low energy effectivefield theory,the model is defined without reference to CSB.Thus,the effectivefield theorist can simply take the mass term m ISS to be a parameter of unknown provenance,or imagine that it arises as a consequence of the dynamics of another gauge group,not included in the Pentagon model.Our insistence on the origin of m ISS in CSB is a strong constraint,because it bounds the scale of SUSY breaking in the model.We will see that this makes it more difficult tofind a working version of the model.5One other place where CSB plays a role in our considerations is our decision to tune the c.c.(almost)to zero near a particular SUSY violating minimum of the effective potential of theflat spacefield theory.It would not be consistent with the hypothesis of CSB to perform this tuning at the SUSic minimum.We will in fact have to choose between two SUSY violating minima of the potential on phenomenological grounds.It is important to note that once we have done this tuning,the supersymmetric states no longer have anything to do with the theory.Our meta-stable SUSY violating world can tunnel to the negative c.c.region of the potential,but the resulting bubble is a low entropy,highly non-supersymmetric,Big Crunch geometry.These tunneling amplitudes are too small to be of any interest.Before sailing for murkier waters,in which we will have to swim in order to get interesting phenomenological consequences of this model,I will list the approximate symmetries of the low energy Lagrangian.The pure N F=N C=5model has a U(5)×U(5)symmetry.The axial U(1)is an R symmetry under which P and˜P have R charge0.This is also a symmetry of the Yukawa couplings of the Sfield,if S has R charge2and the up and down Higgsfields have opposite R charge.On the other hand the mass term m ISS breaks U(1)R and is required to be fairly large for phenomenological reasons.This term also breaks SU(5)×SU(5)to its diagonal subgroup.The Yukawa coupling g S and the standard model gauge couplings break the diagonal SU(5)down to SU(1,2,3)of the standard model.The meta-stable ISS vacuum spontaneously breaks the remaining U(1)Penta-baryon symmetry.The Goldstone boson is thefield defined by<B>=Λ5e ib/Λ5=<˜B>∗,in the ISS vacuum.We call this the pentonfield,though a catchier name might be found,if one were willing to put in the effort to think about it.In addition to these continuous low energy symmetries,the Pentagon has an anomaly free Z5subgroup of the axial symmetry which gives P and˜P charge one. The mass term m ISS breaks this symmetry as well as the U(1)R but preserves a diago-nal Z R5subgroup.This is inconsistent with the tenets of CSB,according to which the c.c.breaks all R symmetries.It would also prevent us from generating gaugino masses. The couplings g S and g T violate this Z R5if they are both non-zero.These couplings must therefore be large at low energy.The usual chiral Lagrangian predictions for a Goldstone boson relate the emission amplitude for a single Goldstone boson in a transition between twofinal states to the change in the spontaneously broken quantum number in the transition.This would predict zero coupling to ordinary quarks and leptons since they do not carry penta-6baryon number.However,there are dimension5operatorsc BΛ5∂µbJµL,which are allowed by the symmetries of the low energy Lagrangian.These are in fact generated by the diagrams of Figure1,involving standard model couplings at the scale Λ5.The nominal estimates for the coefficients arec B∼α23(Λ5),c L∼α22(Λ5),where these are running gauge couplings,at the indicatedscale.Figure1:Diagrams leading to penton interaction with standard model currents.Gauge bosons are any charge and color neutral pair in SU(1,2,3).The RHS loop could contain leptons.These terms in the action are total derivatives if we neglect the violation of baryon and lepton number by electroweak instantons,but they will be important in the early universe if there are temperatures as high as the electroweak sphaleron mass.Under laboratory conditions,the dominant dimension5coupling of the penton to normal matter comes from similar dimensionfive couplings to non-conserved neutral hadronic currents like beauty,charm,and strangeness.They are suppressed by two powers ofα3(Λ5)and are proportional to quark mass differences in units of the QCD scale(for light quarks).They are of the formα23m FΛ5JµF,where JµF is aflavor current.Note that analogous couplings to axial currents are suppressed by further powers of electroweak gauge couplings,because the SU(5)×SU(3)gauge theory is invariant under parity.Thus pentons will be predominantly emitted in charged current weak decays,since the amplitudes are proportional to the divergence of the correspondingflavor current.As we will see in the section on dark7matter,pentons are very light,.1−1eV,and will escape from the detector as missing energy.Models with very low energy SUSY breaking cannot contain the usual SUSic can-didates for dark matter.Even if R parity is conserved,the LSP is the gravitino,which is relativistic at the usual scale of matter domination.It is also relatively strongly coupled and so the NLSP is not cosmologically meta-stable.In previous attempts to construct a phenomenology based on CSB,I suggested that baryons of the new strong interactions(penta-baryons in the Pentagon model)would be the dark matter.This is not possible if penta-baryon number is spontaneously broken.Instead I will suggest that the dark matter is a condensate of pentons.I will show that this is reasonable if the early universe produces a sufficiently large penta-baryon asymmetry.3.Known unknownsWe will accept the hypothesis of ISS that the Pentagon model has a meta-stable SUSY violating state withflat space vacuum energy of order m2ISSΛ25.ISS characterize this as a state which has vanishing expectation value for penta-meson operators.However,in the presence of m ISS and the couplings g S and g T there is no symmetry which prevents the combinations P A i˜P j A(δi j,Y i j)from getting non-zero VEVs.Thus,we expect these bilinears to have VEVs of order KΛ25at the SUSY violating minimum,where K involves powers of g S,T if these are small.We will tune the parameter W0in the SUGRA formula for the effective potential,so that the c.c.at this SUSY violating minimum is of order the observed c.c.,λ.Actually we must resolve one further ambiguity in choosing the SUSY violating vacuum.When m ISS=0there are two solutions of the F and D term constraints for the Higgsfields and the singlet S:h u,d=0,g S p A i˜p j A Y i j=−3g T s2,ands=0,g S p A i˜p j A Y i j=−gµh u h d,where lower case letter represent the scalar components of chiral superfields.The Higgs VEVs in the second equation are oriented so that electromagnetism is unbroken and tanβ,the ratio of Higgs VEVs is one.In the presence of the SUSY breaking parameter m ISS there will be a similar ambiguity in the choice of VEVS at the SUSY violating vacuum.However,s=0is no longer a stationary point of the effective action since there are no unbroken symmetries which preserve it.On the other hand,thefirst minimum will still have h u,d=0.We8will choose to tune the c.c.toλat the stationary point where SU(2)×U(1)is broken .The other SUSY violating stationary point of theflat space potential may then have either positive or negative c.c.,while the erstwhile SUSic states will have negative c.c. .None of the other stationary points of the potential represent long lived states of the universe once gravity is taken into account.The Pentagon model thus has a stationary point of its effective potential with spontaneously broken SUSY(F∼m ISSΛ5),and SU(2)×U(1)→U(1)EM with |h u|∼|h d|∼Λ5,which we will take to represent the real world.SUSY breaking is communicated to the standard model by two distinct mecha-nisms.Since s,h u,h d are all non-zero,the Higgs superfields have F terms which will contribute tree level masses to squarks and sleptons.In addition there are more or less conventional gauge mediated contributions.The latter are the dominant contributions for gaugino masses as well as the masses of squarks and sleptons,apart from the top squark.Gaugino masses are estimated from one loop standard model diagrams with pentaquark superfields in the loop,and arbitrary numbers of penta-gauge bosons.If we compare to conventional gauge mediated scenarios,these diagrams are enhanced by a factor of5 Y2∼16.7(where the sum is over the weak hypercharges in the5 representation of SU(5)GUT).As we will see,this means that the gaugino to squark or slepton mass ratios are larger by a factor∼4than they are in conventional gauge mediated models.The corresponding two loop contribution to e.g.the right handed charged slepton squared mass is enhanced by the same factor.Thusm˜eR∼4α1Λ5.In the standard modelα1250so we need F/Λ5>6.25TeV in order to satisfy the experimental bounds on this mass.The CSB prediction for F is of order10TeV2so this impliesΛ5∼1.6TeV.The ISS mass parameter then satisfiesm ISS4A proof of this fact has not yet been found.9The phenomenologically preferred value for m ISS/Λ5is not in the perturbative regime.For example,a corresponding ratio in QCD would correspond to quark masses of order600MeV.Thus,it is not implausible that the meta-stable state exists in the phenomenologically required region.Note also that the additional hypercharged states in the Pentagon model might make the couplingα1,which appears in the es-timate for the slepton mass,slightly larger,and consequently loosen the bound on F/Λ5.Nonetheless,these considerations suggest that the lightest charged sleptons in the Pentagon model of SUSY breaking cannot be significantly heavier than the current experimental lower limits.Thus,we expect to see these sleptons produced at LHC. Since the LSP is the light gravitino,with couplings of order1/F,slepton pair produc-tion will result in spectacularfinal states with two hard leptons,other hard particles, and missing energy,a classic signal for low energy SUSY breaking[5].It is however likely that the NLSP in this model is not a gaugino,because of the extra factor of4 in gaugino masses.The other hard particles in thefinal state depend on the nature of the NLSP,which we cannot determine at this time.It is worth pointing out that these estimates of the scale of SUSY breaking give a gravitino mass of order5×10−3eV.Such gravitinos are perfectly consistent with Big Bang Nucleosynthesis,in sharp contrast to conventional gauge mediated models.They are light enough,and their longitudinal components strongly coupled enough,that one might imaginefinding them in experiments probing for short distance modifications of gravity.It has also been suggested that they might be found at the LHC[6].Another difference between the Pentagon model and conventional gauge mediated models is that the SU(2)×U(1)violating top squark mass generated by the F term of H u is comparable to or larger than the gauge mediated mass.This is because our model effectively generates a sizable effectiveµterm,from the VEV of S.Unfortunately,the strong coupling physics at the scaleΛ5prevents us from making very precise statements about the spectrum of superpartner masses.In particular,there are three potentially worrisome tuning problems that I have not had the calculational skill to address.First,our estimates of gaugino and right handed slepton masses depended on the assumption that the couplings g S and g T were strong enough that there is no further loop suppression of gaugino masses(recall that these couplings broke the discrete R symmetry left over by m ISS).In particular one may worry that g T is not asymptotically free(it would appear to be renormalized only by wave function renormalization of the gauge invariant Sfield)so that a large value at low energy may lead to a Landau pole well below the unification scale.The second potential tuning is the ratio of the electroweak scale,250GeV toΛ5. For g S of order1,this is of order1/6.It scales like g S for small g S,since the VEV of the bilinear P Y˜P is of order g S,but small g S would alter our estimates for gaugino10and charged slepton masses in an unpleasant fashion.Finally,one may worry aboutthe“little hierarchy problem”.Precision electroweak measurements seem to prefer aHiggs mass below200GeV,and this may also be a little tuned in the current model.It is hard to tell whether one should take factors of6−10seriously in a model whereit is so hard to make precise calculations.One thing that appears safe is direct interference of the Pentagon degrees of freedomwith precision electroweak measurements.These would primarily affect the Peskin-Takeuchi S-parameter,but with our estimates ofΛ5and m ISS the effects seem to besmall5.These same estimates suggest that the expected rich“penta-hadron”spectrummay be beyond the discovery reach of the LHC.Scaling up from QCD we might expectpenta-mesons in the6−10TeV range.Penta-baryons will probably be unstable todecays into penta-mesons and pentons,with life-times of orderΛ−15.The penton itselfis the only light remnant of the penta-hadron spectrum.As discussed above,it shouldbe produced in association with ordinary charge changing weak decays and can besearched for in low energy experiments,rather than the LHC.4.Baryon number,lepton number,andflavor4.1B and L violating operators of dimension4and5A central element in CSB is the discrete R symmetry which guarantees Poincare in-variance in the the limiting model.This can be put to other uses.In[7]I showed thatit can eliminate all unwanted dimension4and5baryon and lepton number violatingoperators in the supersymmetric standard model.This is sufficient to account for ex-perimental bounds on baryon and lepton number violating processes.The interaction d2θH2u L2,should not be forbidden by R.I will adopt the philosophy of a previous paper and insist that the texture of quark and lepton Yukawa couplings,as well asneutrino masses,are determined by physics at the unification scale.We will choose the R charge of SSMfields to be independent of quark and leptonflavor,and denote it by the name of the correspondingfield.All R charges are tobe understood modulo N,where Z N is the R symmetry group.In the remodeledPentagon model,we must choose N=4in order to accommodate the g T S3term inthe superpotential.We will also impose anomaly freedom for the discrete R symmetry.That is,the’t Hooft interactions generated by all instantons should be invariant.Thisleads to the three constraints(all equations in this section are equalities mod4):5(P+˜P)=0(4.1)6Q+3¯U+3¯D+5(P+˜P)=0(4.2)H u+H d+9Q+3L+5(P+˜P)=0(4.3) In writing these equations,we have taken into account the gaugino charges,and dropped terms that are explicitly zero ing thefirst anomaly equation and dropping more terms which vanish mod4,the second two equations can be simplified to:6Q+3(¯U+¯D)=0,(4.4)3Q+L=0.(4.5) The condition that the standard Yukawa couplings are allowed by R symmetry isL+H d+¯E=Q+H d+¯D=Q+H u+¯U=2.(4.6) The coupling SH u H d requiresH u+H d=0.(4.7) Note that these conditions forbid the standardµterm d2θH u H d,.We will also impose2L+2H u=2to allow the dimension5F term which can generate neutrino masses.The renormalizable dynamics of the Pentagon gauge theory preserves allflavor symmetries of the standard model.This forbids the generation of the neutrino seesaw term with coefficient1We can solve for all of the R charges in terms of L and H d:Q=−3L¯E=2−L−Hd¯D=2+3L−Hd¯U=2+3L+H.dIn addition we have the relation2L=2H d+2.The inequalities which forbid dangerous operators are all satisfied if and only if L is odd and H d is even.Any choice satisfies the last constraint,so we have four solutions L=±1,H d=0,2.4.2Flavor and CPThe Pentagon shares with generic gauge mediated models the property that the only terms in the low energy Lagrangian that are not invariant under the SU(3)Q×SU(3)¯U×SU(3)¯Dflavor group of the standard model,are the quark and lepton Yukawa couplings, and the neutrino seesaw term.As a consequence it has a GIM mechanism,andflavor changing neutral currents are suppressed below experimental upper bounds.Similarly, leptonflavor changing processes likeµ→e+γare within experimental limits.Quark and leptonflavor changing processes,in addition to those induced by the neutrino seesaw term,will come from dimension6operators.We can assume that they are scaled by the same operator M U∼1015GeV as the neutrino seesaw.Note that the restriction to dimension6operators is non-trivial and depends on the fact that dimension5superpotential terms like Q2¯U¯D(with variousflavor combinations)are forbidden by the Z4R symmetry,although they conserve baryon and lepton number. Flavor violation comes predominantly through SSM loop graphs.The remodeled Pentagon thus solves most of the problems of generic SUSic models. However,it does have CP violating phases in addition to the usual CKM parameter. To see this,perform the following sequence of transformations.•A U A(1)transformation on quarks,to eliminate the QCDθangle,θ3.•A similar U A P(5)transformation on penta-quarks to eliminateθ5.•An anomaly free U R(1)transformation,to eliminate arg m ISS.13•A common phase rotation on H u,d to eliminate argdetλuλd.•A phase rotation of S to eliminate arg gµ.We are left with the phases of g S,T(as well as phases in the neutrino see-sawterm and CKM matrix)as physical CP violating parameters.When we integrate outscales≫ΛQCD,these phases will infect the determinant of the renormalized quarkmass matrix and are likely to give rise to an electric dipole moment for the neutronwhich is incompatible with experimental bounds.The upside of this result is that thepotentially troublesome axion,which roamed the halls of the old Pentagon,no longerexists.Counting one of these two phases as a stand in forθ3we see that the Pentagonmodel has six new physical parameters,the absolute values of m ISS,Λ5,g S,T,µand onecombination of the phases of g S,T in addition to the parameters in the standard modelLagrangian.Of these,|m ISS|is roughly determined by the rules of CSB.The three Yukawa couplings of the Sfield are required to be reasonably large.We will discussthe consequences of this assumption in the section on unification of couplings.5.Dark matterCSB,like any model with a maximum SUSY breaking scale of order<100TeV,doesnot have a cosmologically stable massive LSP.Even if R-parity is preserved,the LSP isthe gravitino,and its longitudinal components are so strongly coupled that the NLSPwill decay to it rapidly,probably in typical particle detectors,and certainly with non-cosmological lifetimes.In previous discussions of CSB,I have suggested baryons of thenew strong gauge group as dark matter candidates and in[8]we showed that this wasa viable option if a sufficiently large penta-baryon asymmetry is generated in the earlyuniverse.The meta-stable ISS SUSY breaking state also breaks penta-baryon numberspontaneously,so penta-baryons are no longer cosmologically stable.Instead,I want to show that with a sufficiently large penta-baryon number asym-metry,the penton can be the dark matter.Assume a penta-baryon asymmetry toentropy ratioǫis generated in the early universe at or after inflationary reheating,andthat there is no significant entropy production thereafter.The universe is radiationdominated and the penta-baryon density at temperature T will ben P B=ǫGT3,where G counts the effective number of massless degrees of freedom in the plasma.Once T drops belowΛ5the penta-baryon density can be written in terms of the penton14field bn P B=Λ5˙b,so we get the equation of motion˙b=ǫG T3M2U d2θ(aP5+b˜P5).We will take the mass scale in these interactions to be the same order of magnitude,∼1015GeV,as that which enters thedimension5operator that leads to neutrino masses and mixings.Below the scaleΛ5these interactions will give rise to a potential for b of orderΛ65M U∼2eV.The potential will begin to affect the cosmological evolution of the penton whenthe kinetic energy generated by the asymmetry is of order the potential.This happensat a temperature T∗given byǫ2G2(T∗)6=Λ85M U∼10−12,this temperature is belowΛ5and so our description of the effects of the explicit symmetry breaking is valid.We will see thatǫhas to be quite large if we want the penton to be dark matter.Indeed,below the scale T∗the penton density will grow relative to the radiationenergy density by a factor T∗ργ=ǫ2G(T∗T.Note that(T∗ǫGM U,so thatρpM UΛ5。
Long arithmetic progressions of primes
γk N 2 (1 + o(1)), (log N )k
is a certain product of “local densities” which is rapidly convergent and positive. We have
(k ) αp =
1 p
p p −1
1For
a tabulation of values of γk]. As k → ∞, log γk ∼ k log log k .
LONG ARITHMETIC PROGRESSIONS OF PRIMES
3
Theorem 1.3 (G.–Tao). For each k
k −1 p p −1 k −1
if p if p
k k.
1−
k −1 p
In particular we compute1
γ3 = 2
p 3
1− 1−
1 ≈ 1.32032 (p − 1)2 3p − 1 ≈ 2.85825. (p − 1)3
and γ4 =
9 2p
5
What we actually prove is a somewhat more precise version of Theorem 1.1, which gives a lower bound falling short of the Hardy-Littlewood conjecture by just a constant factor.
1
x, x + d, . . . , x + (k − 1)d
2
BEN GREEN
theorem tells us that P(Ej ) ≈ 1/ log N. If the events Ej were independent we should therefore have P(x, x + d, . . . , x + (k − 1)d are all prime) = P We might then conclude that #{x, d ∈ {1, . . . , N } : x, x + d, . . . , x + (k − 1)d are all prime } ≈ N2 . (log N )k
新视野大学英语第三版读写教程4
第一单元1 As the gender bariers crumbled ,the number of women working as lawyers,doctors, or bankers began to increase significantly from the mid-20th century随着性别歧视者的瓦解，从事律师、医生或银行家工作的女性人数从20世纪中叶开始显著增加。
2 With the data olleted each year, the owner of the shop can discern customer treiendsand how things like weather and economic indicators affect sales performance.根据每年收集的数据，商店的所有者可以辨别顾客的需求以及天气和经济指标等因素如何影响销售业绩。
3 His supervisor pushes and motivates him in such a positive manner that he is not onlyable to reach but to surpass . his personalgoals.他的主管以积极的方式推动和激励他，使他不仅能够达到，而且能够超越。
他的个人爱好。
4 He is a man with a(n) shrewd business sense. He has builthis initial investment into asubstantial and even excessively large fortune.他是一个有精明商业头脑的人。
他已经把最初的投资建立在一个绝对的甚至是巨额的财富上。
5 The conversion of nuclear radiation directly into electricity was an exciting possibilitythat was being vigorously explored in many .laboratories in the 1950s.直接将核辐射转化为电能是一种令人兴奋的可能性。
新视野大学英语第四册十五选十原文及翻译
1Have you ever known anyone famous If so; you may have found that they are remarkably similar to the rest of us. You may have even heard them to people saying there is anything different about them. "I'm really just a normal guy;" an actor who has recently rocketed into the spotlight. There is; of course; usually a brief period while they are popular when they actually start to believe they are as great as their fans suggest. They start to wear clothes and talk as if everyone should hear what they have to say. This period; however; does not often last long. They fall back to reality as fast as they had risen above it all. What will it feel like to soar to such and look down like an eagle from up high on everyone else And what will it feel like to have flown so high only to from your dream and realize you are only human Some only see the in losing something they had gained. They often make attempts to regain what they lost. Often these efforts result in even greater pain. Some become financially and emotionally. The only real winners are those who are happy to be back on the ground with the rest of us. 你有没有见过名人吗如果是这样的话;你可能会发现;他们对我们非常相似..你可能听说过他们的人说的有什么不同呢..”我真的只是一个普通人;”一位演员;最近飙升到了聚光灯下..有;当然;通常是一个短暂的时期;他们是受欢迎的;他们真的开始相信他们是球迷们为伟大的建议..他们开始穿上衣服;说每个人都应该听听他们要说些什么..然而;这一时期;常常不长久..他们回到现实;他们克服了所有的速度..你会觉得翔这样往下看像每个人从高处一只老鹰吗什么将它感觉像飞得如此之高的只是从你的梦和意识到你是人吗一些只能看到失去他们拥有的东西..他们经常试图恢复他们失去了什么..这些努力导致更大的痛苦..一些成为财政和感情..唯一的真正的赢家是那些高兴回来对我们其余的地面..2Have you ever heard of Jon Stewart He is currently one of the most popular comics on television. His pessimistic view of the politics and government laughter; thought and even anger. He has a clever wit that often runs into with some government policies. His whole show is to making fun of the nonsense that occurs in politics. But; what makes his show so is his ability to tell his jokes with intelligence."It's not just comedy;" said one media expert. "His comments have a lot of over a very large audience in America. He has a lot of political power."Recently Stewart was a guest on a news show about politics. The host journalist a heated debate when he about Stewart's responsibility to the American public. Stewart argued that while the content of the script for his show may be political in nature; his primary is to entertain. The host journalist; however; emphasized the political influence of hisperformance. The argument ended up anger from both parties. The incident how sensitive some people can be to what others find funny. It also showed how important comedians have become to politics.你听说过乔恩斯图尔特他目前是电视上最受欢迎的漫画..他的悲观看法的政治和政府的笑声;思想甚至愤怒..他有一个聪明机智;常常遇到一些政府的政策..他是整个节目要取笑;发生在政治废话..但是;是什么让他这么是他用智慧告诉他的笑话的能力..“这不仅仅是喜剧;”一个媒体专家说..”他的评论在美国一个非常大的观众有很多..他有一个很大的政治权力..”最近斯图尔特在一个关于政治新闻节目的嘉宾..主持人问激烈的辩论时;他对斯图尔特的责任;美国公众..斯图尔特认为;他的表演剧本的内容可能是政治性质的;他的主要是娱乐..主机的记者;但他的表现;强调政治的影响..争论的双方最终愤怒..这一事件如何敏感的一些人可以对别人觉得好笑..它也显示了重要的喜剧演员已经成为政治..3What happens in America when someone becomes disabled and cannot do the kind of work they did in the past If someone has been injured on the job; they are supposed to the medical worker; who would certify that there was a problem. Then; they may receive from the company. If the company provides an ; the person may receive money monthly to make up for lost wages. The person who has been disabled may also take the company to court if safety was at the workplace. This usually resultsin of a payment to settle the dispute. In addition; all workplaces are required to pay money to the government for a program to take care of people disabled on the job. One in this program requires workplaces where more injuries to pay more money. For this reason companies that require heavy physical labor take safety very seriously. Most people disability insurance. They think it is that a person should get paid without working. In fact; this benefit is usually not enough to cover the rent and other bills of those who receive it. Most of the disabled still want to work; but from the injury and training for other types of employment takes time.在美国;当有人成为残疾;不能做这样的工作他们在过去发生了什么如果有人在工作中受伤;他们应该对医务工作者;谁能证明有问题..然后;他们可能会收到来自公司..如果公司提供了一个N的人可能会收到钱;每月以弥补损失的工资..他已被禁用的人也可能是在工作场所安全公司采取法院..这通常会导致在解决争端付款..此外;所有的工作场所都必须付钱给政府一个程序来照顾残疾人工作的人..在这一程序需要工作场所更伤付出更多的钱..为此;公司需要繁重的体力劳动中采取安全非常重视..大多数人伤残保险..他们认为这是一个人不用工作就获得报酬..事实上;这样做的好处是通常不足以覆盖那些谁收到的租金及其他费用..大多数残疾人仍要工作;但从损伤和其他类型的就业培训需要时间..4Mr. Li runs a small trade company in Sichuan province. He used to be worried about the sales of his goods; but now he simply logs on to the Internet and the information about his company to almost anywhere. He now has so many resources at his than before. He has even started to in foreign countries and make money almost anywhere.The revolution has certainly changed the way we look at the world. And; most importantly; it allows people to get equal to the information. People in less developed areas of the world are taking of the benefits as well. One person says; "I used to have a small farm; but now I am doing international business." This is just one of the many benefits of the information . There are; however; some challenges we will have to face. For example; there is a great deal of concern over in the Information Age. Mr. Li this point. Hopefully; we can solve this problem in the near future.李先生经营一家小贸易公司在四川省..他是担心他的货物的销售;但现在他只是登录到互联网和他的公司信息几乎任何地方..他现在有这么多的资源在他比以前..他甚至已经开始在国外;几乎任何地方赚钱..革命已经改变了我们看待世界的方式..而且;最重要的是;它让人们获得平等的信息..人在不发达的地区是以有益..一个人说;“我有一个小农场;但现在我做国际业务..”这是一个信息的许多好处..有;然而;一些挑战;我们将要面对的..例如;有担心在信息时代大量..李先生这一点..我希望;我们可以解决这一问题在不久的将来..5How do you spend your time when you're alone Do you turn up your music as loud as you can and listen to your own entertainment Do you buy yourself the biggest steak you could find and sit down to a good meal It has been my observation that these activities can be the best type of for a troubled mind. It is crucial for humans to find some in life. They must find some time to let the universe go spinning on without others' . The portion of this world that to one person is increasingly becoming smaller. And whatever we do have we must with others. Therefore; our ability to maintain a healthy balance between social and personal pursuits is being challenged. Inspiration in solitude is a major not only for poets and philosophers but for ordinary people as well. A healthy adult needs "alone-time"; time to on what is truly important to them. When you are alone; you can out your soul until it fills up the whole room; and use your freedom; moving at your own pace. However; it's important to stay . Don't forget that in order to be a healthy part of others' lives; you must yourself be healthy.你怎样度过你的时间当你孤单吗你把音乐的声音可以听你自己的娱乐你给自己买你能找到和坐下来吃一顿最大的牛排据我观察发现;这些活动可以是最好的一个困扰的心灵..人类的生活中找到一些至关重要的是..他们必须找到一些时间让宇宙去纺纱在没有别人..这个世界的一部分;一个人是越来越小..无论我们做我们必须与其他人..因此;我们维持社会和个人追求健康的平衡受到挑战的能力..独处的灵感是诗人和哲学家的主要不但是对于普通人一样..一个健康的成年人需要“独处的时间”；时间对什么是真正重要的是他们..当你孤单的时候;你可以从你的灵魂;让它充满整个房间;用你的自由;你可以按自己的节奏行动..然而;重要的是要保持..别忘了;为了别人的生命健康的一部分;你必须自己是健康的..6In the past several years; many news stories about corporate greed have come to surface. The illegal practices of some executives have impacted our economy. What makes this worse is that these executives seem to have the of some political leaders. Some of the executives even lawmakers. Recently a member of Congress from California was caught demanding gifts from interest groups in for supporting new laws. A few top leaders in the government are under for illegal activities. This doesn't even the surface of the problem. A few years back a company made many purposeful errors to fool investors. Many believe that one reason the problem became so big was that our nation's top leaders the company. By the time the truth was ; many innocent people had lost their entire savings. There seems to be more and more companies that the public's trust for their own interests. This calls for laws and strictregulations to put the illegal practice to an end.在过去的几年中;许多企业的贪婪的新闻故事来表..一些高管的非法行为已经影响了我们的经济..让事情变得更糟的是;这些高管们似乎都有一些政治领导人..一些高管甚至议员..最近;一个来自加利福尼亚州的国会议员被要求从利益集团支持的新法律的礼物..在政府的一些高级领导人在进行非法活动..这不是问题的表面..几年前;一个公司取得了许多有欺骗投资者的错误..许多人认为;一个理性的问题变得如此之大;我们的国家的最高领导人;公司..通过事实的时候;许多无辜的人失去了他们所有的积蓄..似乎有越来越多的公司;公众的信任;为自己的利益..这就要求法律严格规定将非法行医的结束..。
选择性必修第四册 Unit 4 Everyday economics(教师版)
Ⅰ.阅读单词——会意1．forehead n．额，前额2．chairwoman n．女主席；女会长3．sunrise n．日出(时分)；黎明；拂晓4．bug n．突然的兴趣，迷恋5．input n．投入(物)6．phase n．阶段，时期7．manufacturer n．制造商；制造公司，制造厂8．cosmetics n．化妆品，美容品9．bonus n．奖金；红利10．entrepreneurial adj.创业的，具有创业精神的11．equator n．赤道12．estate n．庄园13．calorie n．卡(路里)14．freshman n．(高中或大学的)一年级学生15．afloat adj.经济上周转得开的；不欠债的16．rational adj.(想法、决定等)合理的，基于理性的17．toddler n．学步的儿童，刚学走路的小孩18．designer clothes名牌服装19．thereby ad v.因此，由此20．supervision n．监督；管理21．theft n．偷窃，偷盗22．purse n．(女式)钱包Ⅱ.重点单词——记形1．blank adj.无表情的，木然的2．potential n．(事物的)潜力，可能性3．obstacle n．障碍，阻碍，妨碍4．purchase v．购买5．superior adj.质量上乘的，优质的6．mild adj.不浓烈的，淡的7．subjective adj.主观的8．interfere v．介入；干涉9．exceed v．超过，超出10．hire v．(短期的)租用，租借11．expense n．费用，花费12．abuse n．滥用Ⅲ.拓展单词——悉变1．dizzy adj.头晕目眩的→dizzily ad v.眩晕地→dizziness n．头昏眼花2．enterprising adj.有创业精神的；有事业心的；有进取心的→enterprise n．企业；事业；进取心3．distribution n．(商品的)分销，经销→distribute v t.分销；分发→distributor n．经销商；分销商4．guidance n．指导，引导→guide v．指导；带领n．向导；导游5．consultant n．顾问→consult v．咨询；商量；查阅6．conventional adj.传统的，常规的→convention n．习俗；常规；惯例7．discriminate v．不公正地区别对待，歧视→discrimination n．歧视8．financial adj.财政的，金融的；财务的→finance n．财政；金融9．accumulate v．积累，积聚→accumulation n．积累10．automatically ad v.自动地→automatic adj.自动的→automate v．使自动化11．sorrow n．令人悲伤的事，不幸→sorrowful adj.使人伤心的；悲伤的12．frustration n．懊丧，懊恼，沮丧→frustrate v t.使沮丧→frustrated adj.沮丧的→frustrating adj.令人沮丧的1．snatch /snætʃ/v t.强夺；攫取；偷窃2．ample /'æmpl/adj.充足的；丰裕的3．robbery /'rɒbəri/n．抢劫；掠夺4．queue /kjuː/n．(人、汽车等的)队、行列v i.排队(等候)5．scheme /skiːm/n．方案；体系；阴谋v i.& v t.密谋；图谋6．weird /w Iəd/adj.古怪的；不寻常的；怪诞的7．debut (also début) /'de I bjuː/n．& v i.(演员、运动员的)首次亮相；初次登台make one’s debut首次亮相8．refine /r I'fa I n/v t.完善；改进；提炼9．adhere /əd'h Iə(r)/v i.黏附；附着adhere to遵循；信守10．trivial /'tr I viəl/adj.琐碎的；微不足道的Ⅳ.背核心短语1．make ends meet使收支仅能相抵2．interfere with妨碍，阻止3．go into debt陷入债务之中，负债4．rent out出租(房屋、房间、土地等)5．at the expense of以损害……为代价6．as to至于，关于7．a world away from与……相差甚远；完全不同8．row upon row鳞次栉比9．be bitten by the...bug爱上……；对……迷恋10．response to对……的反应11．at rock-bottom prices以最低价12．do a further favour再帮个忙Ⅴ.悟经典句式1．Though she welcomes the new entrepreneurial spirit，she advises that people be realistic and seek guidance from expert consultants before rushing into things.[advise that sb (should) do]尽管她希望看到新的创业精神的涌现，但她也建议人们要现实一些，在仓促行事之前先寻求专业顾问的指导。
A spectral order method for inverting sectorial Laplace transforms
1
its Laplace transform. We will always assume that U (z ) admits a holomorphic extension to the complement W of some acute sector Σδ = {z ∈ C : | arg(−z )| ≤ δ }, 0<δ< π , 2 (1.1)
an that there exist constants M > 0 and µ ∈ R such that U (z ) ≤ M , |z |µ z∈ / Σδ . (1.2)
The last requirement, with µ ≥ 1, means that u admits a bounded and holomorphic extension to any sector of the form | arg(z )| ≤ δ ′ , with 0 < δ ′ < π/2 − δ . If µ < 1, we select an integer number m ≥ 1, with m + µ ≥ 1, and set V (z ) = U (z )/z m. Then, by the previous remark, V (z ) is the Laplace transform of a mapping v : (0, +∞) → X , which admits a bounded and holomorphic extension to sectors with semi-angle δ ′ as before, and now u is understood to be the derivative of order m of v . Notice that in case U (z ) satisfies a similar inequality U (z ) ≤ M , |z − ω |µ z∈ / ω + Σδ ,
选必B4U4-Starting out and vocabulary (1)
Lead in
Q1：What is money and what is currency ?
Definition:
Money is a medium that can be exchanged or traded for goods and services. Money can be used to measure the value of those goods and services at the current market
1. What is the video about?
The video is about a brief history of currency, or the development of currency.
2. What stages are mentioned in the video? What are they like?
New words and phrases
designer clothes 名牌服装 rent out 出租（adv.因此,由此 supervision [ˌsjuːpəˈviʒən] n.监督,管理 expense [iksˈpens] n.消费；花费 at the expense of 以损害...为代价 abuse[əˈbjuːz] vt.滥用；虐待 theft[θeft]n.偷窃 purse[pəːs] n.钱包;皮包
New words and phrases
cosmetics[kɔzˈmetiks] n.(pl.)化妆品 purchase [ˈpəːtʃəs] vt.购买;获得 distribution [ˌdistriˈbjuːʃən] n.分发;分配;分布;销售 bonus [ˈbəunəs] n.奖金;额外酬金;红利; entrepreneurial[ˌ ɔntrəprə'nə:riəl]adj. 企业家的，
Finite-size Effects from Giant Magnons
†
Correspondent fellow at Steklov Mathematical Institute, Moscow
Contents
1 Introduction and summary 2 String theory in a uniform gauge 3 Giant magnon in uniform gauge 3.1 Soliton solution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3.2 Infinite J giant magnon . . . . . . . . . . . . . . . . . . . . . . . . . 3.3 Finite J giant magnon . . . . . . . . . . . . . . . . . . . . . . . . . . 4 Global symmetry algebra 5 Giant magnon in the conformal gauge 6 Two-spin giant magnon A Some explicit formulas B Finite J corrections to the dispersion relation C 2-spin giant magnon at finite J 2 8 14 14 18 19 21 23 28 30 32 37
1
1
Introduction and summary
Recent studies of string theory in AdS5 × S5 and the dual N = 4 super YangMills theory, motivated by the AdS/CFT duality conjecture [1], have led to new interesting insights into the problem of finding the spectrum of quantum strings in the AdS5 × S5 geometry. It seems that this complicated problem can be addressed in two stages. String states can be naturally characterized by the charges they carry under the global symmetry algebra of the AdS5 × S5 space-time. In the first stage one considers states for which one of the angular momenta on the five-sphere is infinite. In this case the problem of finding and classifying the corresponding string states simplifies considerably. In the second stage, it may then be possible to bootstrap this analysis to string states with finite charges. Perhaps the easiest way to appreciate the simplifying features of the infinitecharge limit is to consider the light-cone gauge-fixed string theory. In the light-cone gauge (for a precise definition see section 2) the gauge fixed world-sheet action depends explicitly on the light-cone momentum, which can be thought of as one of the global symmetry charges. By appropriately rescaling a world sheet-coordinate, the theory becomes defined on a cylinder of circumference proportional to the value of the light-cone momentum. At this stage, one can consider the decompactifying limit, i.e. the limit in which the radius of the cylinder goes to infinity while keeping the string tension fixed [2]-[9]. In this limit one is left with the theory on a plane which leads to significant simplifications. In particular, the notion of asymptotic states is well defined. Furthermore, since the light-cone gauge fixing manifestly breaks conformal invariance, the world-sheet theory has a massive spectrum. This theory is (believed to be) integrable at the quantum level, and hence a multi-body interaction factorises into a sequence of two-body interactions.1 Thus the problem of solving the theory basically reduces to the problem of finding the dispersion relation for elementary excitations and the two-body S-matrix. These two quantities have not as yet been determined from the first principles of field theory. However, the insights coming from gauge theory [11]-[14] from semi-classical string quantisation [11, 15][20] as well as from the analysis of classical strings [21]-[26] lead to a conjecture for the form of the dispersion relation and the corresponding S-matrix [27, 28]. From the perspective of relativistic field theory, both the dispersion relation and the Smatrix have an unusual form. The dispersion relation has been conjectured to be p λ sin2 . (1.1) 2 π 2 The appearance of the sin p/2 in the dispersion relation is a common feature of theories on a lattice, but its origin from the world-sheet perspective remains obscure, given that the string world-sheet is continuous. Secondly, the dispersion relation is ǫ(p) = 1+
新视野大学英语第三版第四册Unit 5单词讲解
(an accident / blame / be attached to) Don’t worry because it was an accident and no blame is attached to students.
作为副业；
作为兼职
短语逆译 on the side
短语应用
她的丈夫是个医生，业余时间做些雕塑。
office. • 他开始了第四届任期。
5. reciprocal
ADJ
• involving two people or groups who agree to help each other or behave in the same way to each other 互惠的；相应的
• • The two colleges have a reciprocal arrangement whereby (凭此，借以) students from one college can attend classes at the other.
denotes the distance covered. 在这个例子中，X表示所用的时间，Y表示所行的距离。 •The red triangle denotes danger. 红色三角形表示危险。 •Here ‘family’ denotes mother, father and children. 此处的family指母亲、父亲和孩子。
世间的；世俗的；现世的
•Although spiritual leader of millions of people, the Pope has no temporal power.
教皇虽然是亿万人的精神领袖，但没有丝毫的 世俗权力。
Words and expressions 单词课件 高中英语人教版(2019)选择性必修第四册
appoint sb. to do
委派某人做某事
1.Kate__w_a_s_a_p__p_o_in_t_e_d___as secretary last month. Now she is making an__a_p_p_o_i_n_t_m_e_n_t__with the marketing manager.(appoint) 2. If you are invited to dinner,you are supposed to arrive no later than the _a_p_p__o_in_t_e_d__(appoint) time. 3.A new engineer was appointed__t_o__d_e_a_l _(deal) with the products returned by customers.
2.dignity n.庄重；庄严；尊严→dignify vt.使显得尊贵；抬 高......的身价→dignified adj.有尊严的；庄重的；庄严的 3.appoint v.任命；委任；安排→appointment n.预约；约 会；委任→disappoint v. 使失望/破灭→disappointed adj. 失望的；沮丧的→disappointing adj.使人失望的 4.guilt n. 内疚；悔恨；有罪→guilty adj.内疚的；有罪的； 有过失的→innocence n.天真；单纯；无罪→innocent adj. 天真无邪的；无辜的
看图猜词
推特安全账户2021年1月8日晚发文称：“在 仔细审查特朗普账户最近发布的推文以及 这些推文的背景后, 我们已永久停封 (suspend)该帐户。”
bonus
suspend
labour
新视野大学英语第三版b4u4texta课文中英对照版
unit4TextAAchievingsustainableenvironmentalism实现可持续性开展的环保主义1Environmentalsensitivityisnowasrequiredanattitudeinpolitesocietyasis,say,beliefindemocracyordisapprovalofplasticsurgery.ButnowthateveryonefromTedTurnertoGeorgeH.W.BushhasclaimedloveforMotherEarth,howarewetochooseamongthedozensofconflictingproposals,regulationsandlawsadvancedbycongressmenandconstituentsalikeinthenameoftheenvironmentClearly,noteverythingwithanenvironmentalclaimisworthdoing.Howdowesegregatet hebestoptionsandconsolidateourvaryinginterestsintoasingle,soundpolicy在上流社会,对环境的敏感就如同信仰民主、反对整容一样,是一种不可或缺的态度。
然而,既然从泰德·特纳到乔治·.布什,每个人都声称自己热爱地球母亲,那么,在由议员、选民之类的人以环境名义而提出的众多的相互矛盾的提案、规章和法规中,我们又该如何做出选择呢显而易见 ,并不是每一项冠以环境保护名义的事情都值得去做。
我们怎样才能别离出最正确选择,并且把我们各自不同的兴趣统一在同一个合理的政策当中呢2Thereisasimpleway.First,differentiatebetweenenvironmentalluxuriesandenvironmental necessities.Luxuriesarethosethingsthatwouldbenicetohaveifcostless.Necessitiesarethosethi ngswemusthaveregardless.Callthisdistinctionthedefinitiveruleofsaneenvironmentalism,which stipulatesthatcombatingecologicalchangethatdirectlythreatensthehealthandsafetyofpeopleis anenvironmentalnecessity.Allelseisluxury.有一种简便的方法。
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For example, the latter is not present in the p = 3 case, i.e. the T6 /Zsequel, we describe all nilpotent algebras Np [41], corresponding to axion symmetries of the R–R and NS–NS scalars for all orientifold models. All Np ’s are nilpotent subalgebras of so(6, 6), are generically non–abelian and contain central charges. There are four of them in type IIB (p = 3, 5, 7, 9) with dimensions 15, 23, 23, 15 respectively, while there are only three of them in type IIA (p = 4, 6, 8) of dimensions 20, 24, 20, respectively. A common feature of these algebras is that they always contain fifteen R–R axionic symmetries, while the extra symmetries correspond to NS–NS B –field axions in the bi–fundamental of GL(9 − p, R) × GL(p − 3, R). A further R–R axion symmetry originates from the SU (1, 1), which acts as electric– magnetic duality on the gauge fields living on the brane world–volume. The corresponding axion field can be identified with the Cp−3 R–R field, as dictated by the coupling
∗
3
Spinoza Institute, Leuvenlaan 4 NL-3508, Utrecht, The Netherlands sergio.ferrara@cern.ch,
♭
e-mail:
⋆
carlo.angelantonj@cern.ch ,
M.Trigiante@phys.uu.nl
Abstract We consider classes of T6 –orientifolds, where the orientifold projection contains an inversion I9−p on 9 − p coordinates, transverse to a Dp–brane. In absence of fluxes, the massless sector of these models corresponds to diverse forms of N = 4 supergravity, with six bulk vector multiplets coupled to N = 4 Yang–Mills theory on the branes. They all differ in the choice of the duality symmetry corresponding to different embeddings of SU (1, 1) × SO(6, 6+ n) in Sp(24+ 2n, R), the latter being the full group of duality rotations. Hence, these Lagrangians are not related by local field redefinitions. When fluxes are turned on one can construct new gaugings of N = 4 supergravity, where the twelve bulk vectors gauge some nilpotent algebra which, in turn, depends on the choice of fluxes.
Carlo Angelantonj1,† , Sergio Ferrara1,2,‡ and Mario Trigiante3,♭
1
CERN, Theory Division, CH 1211 Geneva 23, Switzerland
2
INFN, Laboratori Nazionali di Frascati, Italy
1.
Introduction
New string or M–theory models are obtained turning on n–form fluxes, which allow, in general, the lifting of vacua, supersymmetry breaking and moduli stabilisation [1]–[24]. Examples of such new solutions are IIB and IIA orientifolds [25, 26, 27, 28, 29], where the orientifold projection (in absence of fluxes) preserves N = 4 or N = 2 supersymmetries. Recently, the T6 /Z2 orientifold with N = 4 supersymmetry [8, 9] and K3 × T2 /Z2 orientifold [24] with N = 2 supersymmetry have been the subject of an extensive study. In these cases, turning on NS–NS and R–R three–form fluxes allows to obtain new string vacua with vanishing vacuum energy, reduced supersymmetry and moduli stabilisation [7, 8, 9, 21, 24]. These features can all be understood in terms of an effective gauged supergravity, where certain axion symmetries are gauged [31, 30, 32]. These are generalised no–scale models [33, 34]. In the present investigation, we consider more general four–dimensional orientifolds with fluxes (both in type IIB and IIA) where the orientifold projection involves an inversion I9−p on 9 − p coordinates, transverse to the Dp–brane world–volume, thus generalising the T6 /Z2 orientifold (with p = 3) constructed by Frey–Polchinski [8] and Kachru–Shulz– Trivedi [9] (see also [10] for a derivation of the complete low–energy supergravity from T–dialysed Type I theory in ten dimensions). Interestingly, their low–energy descriptions are all given in terms of N = 4 supergravity with six vector supermultiplets from the closed–string sector, coupled to an N = 4 Yang–Mills theory living on the Dp–brane world–volume. However, despite the uniqueness of N = 4 supersymmetry, the low–energy actions crucially differ in the choice of the manifest “duality symmetries” of the Lagrangian, since different sets of fields survive the orientifold projection, and therefore different symmetries are manifestly preserved. Leaving the brane degrees of freedom aside, these duality symmetries are specified by their action on the (twelve) bulk vectors. Actually, N = 4 supergravity demands that such symmetries be contained in SU (1, 1) × SO (6, 6) [35, 36] and act on the vector field strengths and their duals as symplectic Sp(24, R) transformations [37]. On the other hand, the symmetries of the Lagrangian correspond to block–lower– triangular symplectic matrices, whose block–diagonal components have a definite action on the vector potentials [38, 39, 40]. For instance, in the orientifold models containing an I9−p inversion, the block–diagonal symmetries always include GL(9 − p, R) × GL(p − 3, R), as maximal symmetry of the GL(6, R) associated to the moduli space of the six–torus metrics. The lower–triangular block contains the axion symmetries of the R–R scalars and of the NS–NS ones originating from the B –field, whenever present1 .