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Branes, Brane Actions and Applications to Field Theory

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We also present an application of branes to compute the spectrum of a conformal field theory in conjunction with the Ads-CFT correspondence. The effect for the latter is proportional to the invariant length of the particle world line.

Supersymmetric p-branes

4Strictly speaking, the !J appearing in Sz is a retreat to the world volume of the superspace form, but we make no notational distinction between superspace quantities and their world volume returns. In the next section, we will see that (2.15) is exactly the condition for supersymmetry of the world volume.

Local Kappa Symmetry

Supersymmetric D-brane Actions

The first term is the supersymmetric generalization of the Dirac-Born-Infeld action (1.32): where for convenience we have set the voltage to one. The supersymmetrization of the field strength in the above is given by. where b is a two-form written only in terms of fermions, whose supersymmetric variation is exact, allowing one to define the supersymmetry variation of A such that F is invariant7. The notation of the previous section shows that for p even, corresponding to type IIA, we can introduce the following formal sums of differential forms:

Super M-branes

  • The Super-membrane
  • The Self-Dual Antisymmetric Tensor in Six Dimensions
  • Fivebrane Action Without Manifest Covariance
  • Fivebrane Action in the PST Formulation

We will write its action explicitly in the following subsection and show that the two-dimensional reduction leads [15] to the type IIA superstring, while the world volume duality [36, 371 connects it to the D2-brane. The rest of this section is devoted to the construction of the bosonic world volume action for the pentabrane, which in itself is a non-trivial task. Since we want to study the two-dimensional reduction of the membrane in the fundamental type IIA string, it is useful to establish a notation that distinguishes eleven-dimensional indices from their ten-dimensional counterparts.

One way to implement duality is to add a Lagrange multiplier term g to the action. To organize the calculations, it is useful to identify the quantities relevant to the operation of the double D2-brane. Now it is easy to guess the content of the world volume field of the five branes: in addition to the scalars parametrizing the transverse motion, there must exist a two-index antisymmetric tensor B corresponding to the gauge field A on the D4-brane .

In the next section, we will see that the self-interacting theory that lives on the five-brane has an action of this type. As discussed in [32], this equation has many solutions, but the one relevant to This transformation is as complicated as the non-manifest general coordinate transformation in the non-covariant formalism.

Chapter 3

  • Brane Actions in Flat Spacetime
    • Gauge-Invariant D-Brane Actions
    • Super D-Branes in Static Gauge
    • Dimensional Reduction

The next step is to use the following fundamental identity1, which holds for any three Majorana-Weyl spinors X I, X2, X3 of the same chirality. In the case of type IIB (p odd), the substitution rll + r3 must be made. I must not be anticommuted past another matrix r before I make this substitution!) The normalization of the b-form in the previous section was chosen so that the formula for S F obtained in this way would combine nicely with the formula for SG in eq. We are now ready to establish the kappa symmetry of action using the procedure of Section 2.2 and prove the results given in Section 2.3.

A natural choice of the kappa metric that leads to surprisingly simple and tractable formulas is to set one of the two Majorana-Weyl spinors that make up 6 equal to zero. After the gauge is fixed, X becomes a world-volume spinor, even though the 4 were originally world-volume scalars, as a consequence of the identification of X P with . For these choices it is the total supersymmetry transformations of the fields that remain in the fixed gauge theory.

Since there is no fundamental difference between them, however, we simply switch these labels in case IIB, so that the formulas then look identical to those in case IIA. In Appendix D we show in detail that the variation of the integrand of S(P) is a total derivative, as required. The transformation with the parameter 1€ describes Volkov-Akulov type supersymmetries, which are broken by the presence of the D-brane.

Appendix A: The Proof of Equation (3.16)

However, this is a little more work to prove, because one needs to know a formula for the dimensional reduction of ((PI. This implies that the supersymmetry transformation formulas in (3.25) retain their form after dimensional reduction for the identities $') = zP-') and. The point is that both sides of the equation we're trying to prove are Lorentz invariant, and a Lorentz transformation of dimension (p+ 1) can bring .F to the special.

Since p is even, there is necessarily a row and a column of zeros, which we have chosen to associate with the time direction, thus making F purely magnetic. One difference is that 3 has an even number of rows and columns, so the canonical form has no rows or columns of zeros.

Appendix B: The Proof of Equation (3.18)

The key to the proof is the ratio3. where i, denotes the inner product operator induced by e, = G. a This is a consequence of the definition of ix ,. for an n-form w and a vector field X. 5 2 ) is a set of equations related to differential forms of order p + 1, the dimension of the world volume. The proof for IIB is similar, except that TS anticommutes with SB(+) which introduces an extra minus sign in the second term.

Appendix C: The Proof of Equation (2.39)

Chapter 4

  • theory Fivebrane Action
    • Supersymmetrization of the Non-Covariant Action
    • General Coordinate Invariance
    • Proof of Kappa Symmetry
    • Supersymmetric Theory in the PST Formula- tion
    • Double Dimensional Reduction

With these choices for Gbc and ?l, we can now write the expansions L1 and L3, which clearly have 1 l d super-Poincar4 symmetry: . where zl and zz are now formed from ?l instead of H. The next step is to construct a supersymmetric expansion of L 2. The rest of the calculation is identical to that for the bosonic theory given in ref. This means that i(1 - y) is a projection operator and half of the components of 8 can be measured.

It works in a way analogous to that of the world volume meter field for D-branes. The point is that L' reduces to L3 and a portion of the non-covariant Wess-Zumino term L2. The p # 5 term is responsible for L3 of the gauge fixed theory, while the p = 5 term represents the X 2 piece of L2 and a portion of the % piece.

So we express everything in terms of the five-dimensional metric G 5 and then use generalized coordinate invariance to set it on the flat metric q. Unlike the case of the membrane, the calculations are too complicated to be done in a clearly Lorentz-invariant way. We have therefore explicitly shown that the two-dimensional reduction of the M-theory five-brane is the type IIA D4-brane.

Chapter 5

The Ads-CFT Correspondence and the Spectrum of Nonlagrangian CFT's

  • Introduction to the Ads-CFT Correspondence
  • The Five-brane System
  • Oscillator Construction of OSp (6,212) Short Multiplets
  • Kaluza-Klein Reduction
  • Kaluza-Klein Reduction of Es-charged Modes

The highest spatiotemporal spin in the multiplet (5.14) is the vector, indicating a short representation of the superalgebra. Now that we have established part of the multiplet structure of OSp(6.212), we can perform our analysis of the bulk S4 Kaluza-Klein modes that survive the Z2 projection. For convenience, we will describe the KK spectrum in terms of the double CFT operators and apply the Z2 projection to the CFT spectrum.

To see the operators dual in KK S4/Z2 modes, we use a simple extension of the above methods. These site carriers transform into antisymmetric (AS) USp(N) ( N must be even) and loosely correspond to oscillations within the 9-brane end of the world. The other operators in (5.25) are superconformal primaries for long multiplets OSp (6.212).

This corresponds to our understanding of the p = 1 operators as dual to the "pure measure" (i.e., no physical degrees of freedom) Ad fields in the doubleton representation of OSp (6.212). They correspond to the center of mass of the M5 branes parallel to the 9 branes and decoupled. These fields connect to the R-symmetry current, the supercurrent and the stress-energy tensor of the boundary CFT, respectively.

Appendix A: Anti-de Sitter Spaces

Columns in this series fit easily into chiral multiplets with primary superconformal scalars in (k+2,k). As in [56], the scalars arising from the vector harmonics (k+2,k) and (k,k+2) have different energies Ads due to a refinement involving the eigenvalues ​​of the covariant derivative E8 in S3. Note that the first multiple in the series contains the dimensionless vector, which carries the E8 gauge symmetry and is coupled to the current dual E8 algebra in the Ads7 CFT limit.

In the last two sections, we got two infinite lists of Kaluza-Klein modes that fit short (or medium) multiplets and therefore correspond to chiral primary operators of the (1, O) theory. We also determined the superconformal dimension of these operators using the group theory of OSp(6,212). Furthermore, one could use the Ads-CFT correspondence to calculate correlation functions of these operators15.

There are several useful representations of especially the one emerging from regions near the horizon of branes described by the coordinates xp, R (as in. For a much more complete treatment of Anti-de Sitter spaces, we refer the reader to Sect. 2.2 of [46].

Appendix B: Superconformal Symmetry

For a much more complete treatment of Anti-de Sitter spaces, we refer the reader to Section 2.2 of [46]. thus avoiding the Coleman-Mandula theorem). We also did not include some coefficients because they depend on the number of dimensions and the number of supersymmetries. In fact, Nahm classified superconformal theories in [66] and showed that they only exist in six or fewer space-time dimensions.

A conformal primary is an operator of minimal dimension in a given Lorentzian representation (scalar, spinor, vector). Since unity imposes lower bounds on the scaling dimension (see [62]), we conclude that there must exist a conformal prime that is annihilated by K. If it is also annihilated by a combination of Q's, it is called a "chiral prime" operator.

Acting with Q on a superconformal primary yields the conformal primaries of the multiplet , so the superconformal multiplet will be shorter (containing fewer conformal multiplets) if we start from a chiral primary. 18 The names encode the fact that the supercharges have the same six-dimensional chirality and the total number of supercharges is 8n, where eight is the dimension of the generic six-dimensional spinor. For a primary chiral operator there exists a combination of Q's such that the anticommutator applied to the operator vanishes.

Conclusions

Bibliography

Tseytlin, "Self-duality of Born-Infeld Action and Dirichlet Three-brane of Type IIB Superstring Theory," Nucl. Warner, “General construction of the unitary representations of anti-de-sitter superalgebras and the spectrum of S4 Compactification of 1 1-Dimensional Supergravity,” Nucl.

Gambar

Table  2.1:  The  "brane-scan,"  composed of  four  sequences usually  labelled  R,C,H,O,  by  analogy with the real, complex, quaternionic and octonionic fields

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