Superstring amplitudes and contact interactions

نویسندگان
چکیده

برای دانلود رایگان متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Scattering Amplitudes and Contact Interactions in Witten’s Superstring Field Theory

The four-massless-particle scattering amplitudes are calculated for Witten’s covariant superstring field theory. The picture-changing effect of the Ramond sector propagator and of the three-boson vertex is displayed. The results agree with the first-quantized prescription of Friedan, Martinet and Shenker except for -the four-boson amplitude, where an extra divergent contact term appears. The ad...

متن کامل

Covariant Multiloop Superstring Amplitudes

Talk given at Strings 2004 In these proceedings, the multiloop amplitude prescription using the super-Poincaré invariant pure spinor formalism for the superstring is reviewed. Unlike the RNS prescription , there is no sum over spin structures and surface terms coming from the boundary of moduli space can be ignored. Massless N-point multiloop amplitudes vanish for N < 4, which implies (with two...

متن کامل

Motivic Multiple Zeta Values and Superstring Amplitudes

The structure of tree–level open and closed superstring amplitudes is analyzed. For the open superstring amplitude we find a striking and elegant form, which allows to disentangle its α–expansion into several contributions accounting for different classes of multiple zeta values. This form is bolstered by the decomposition of motivic multiple zeta values, i.e. the latter encapsulate the α–expan...

متن کامل

Modular Forms and Three Loop Superstring Amplitudes

We study a proposal of D’Hoker and Phong for the chiral superstring measure for genus three. A minor modification of the constraints they impose on certain Siegel modular forms leads to a unique solution. We reduce the problem of finding these modular forms, which depend on an even spin structure, to finding a modular form of weight 8 on a certain subgroup of the modular group. An explicit form...

متن کامل

Lorentz-covariant Green-schwarz Superstring Amplitudes

In a recent paper, the BRST formalism for the gauge-fixed N=2 twistor-string was used to calculate Green-Schwarz supersring scattering amplitudes with an arbitrary number of loops and external massless states. Although the gauge-fixing procedure preserved the worldsheet N=2 superconformal invariance of the twistor-string, it broke the target-space SO(9,1) super-Poincaré invariance down to an SU...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

ژورنال

عنوان ژورنال: Nuclear Physics B

سال: 1988

ISSN: 0550-3213

DOI: 10.1016/0550-3213(88)90622-0