WIGNER THEORY OF THE NAMBU STRING: (II) THE CLOSED STRING

A set of relative variables for the closed string with P2>0 is found, which has Wigner covariance properties. They allow one to obtain global Lorentz-invariant abelianizations of the constraints, like for the open string, and then global Lorentz-invariant canonically conjugated gauge variables are found. But now there are two extra zero modes in the constraints and in the gauge variables, related to the gauge arbitrariness of the origin σ0 of the circle σ∈(−n, π) embedded in Minkowski space, σ↦xμ(σ). By means of the multitemporal approach a noncanonical redundant set of Dirac observables for the left and right modes is defined; they transform as spin-1 Wigner vectors and satisfy constraints of the same kind as in σ models. The quantization is not made, because a canonical basis of observables is still lacking, but the program to be followed to find them is just the same as the one delineated for the case of the open string.

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Geometry of orientifold vacua and supersymmetry breaking

Journal of High Energy Physics ◽

10.1007/jhep07(2021)104 ◽

2021 ◽

Vol 2021 (7) ◽

Author(s):

Thibaut Coudarchet ◽

Emilian Dudas ◽

Hervé Partouche

Keyword(s):

Field Theory ◽

Supersymmetry Breaking ◽

Effective Field Theory ◽

Scalar Potential ◽

Open String ◽

Closed String ◽

Effective Field ◽

Internal Space ◽

Gravitino Mass ◽

The One

Abstract Starting from a peculiar orientifold projection proposed long ago by Angelantonj and Cardella, we elaborate on a novel perturbative scenario that involves only D-branes, together with the two types of orientifold planes O± and anti-orientifold planes $$ {\overline{\mathrm{O}}}_{\pm } $$ O ¯ ± . We elucidate the microscopic ingredients of such models, connecting them to a novel realization of brane supersymmetry breaking. Depending on the position of the D-branes in the internal space, supersymmetry can be broken at the string scale on branes, or alternatively only at the massive level. The main novelty of this construction is that it features no NS-NS disk tadpoles, while avoiding open-string instabilities. The one-loop potential, which depends on the positions of the D-branes, is minimized for maximally broken, non-linearly realized supersymmetry. The orientifold projection and the effective field theory description reveal a soft breaking of supersymmetry in the closed-string sector. In such models it is possible to decouple the gravitino mass from the value of the scalar potential, while avoiding brane instabilities.

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GAUGE FIELDS ON TORUS AND PARTITION FUNCTION OF STRINGS

International Journal of Modern Physics A ◽

10.1142/s0217751x89000170 ◽

1989 ◽

Vol 04 (02) ◽

pp. 389-400 ◽

Cited By ~ 2

Author(s):

A. NAKAMURA ◽

K. SHIRAISHI

Keyword(s):

Partition Function ◽

Wilson Loop ◽

Open String ◽

Closed String ◽

Point Of View ◽

Gauge Fields ◽

Partition Functions ◽

Zero Modes ◽

Background Fields ◽

String Theories

In this paper we consider the interrelation between compactified string theories on torus and gauge fields on it. We start from open string theories with background gauge fields and derive partition functions by path integral. Since the effects of background fields and compactification correlate only through string zero modes, we investigate these zero modes. From this point of view, we discuss the Wilson loop mechanism at finite temperature. For the closed string, only a few comments are mentioned.

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FINITENESS AND DECOUPLING IN OPEN STRING THEORIES

International Journal of Modern Physics A ◽

10.1142/s0217751x89001837 ◽

1989 ◽

Vol 04 (17) ◽

pp. 4353-4389 ◽

Cited By ~ 2

Author(s):

JAN GOVAERTS

Keyword(s):

Gauge Group ◽

Open String ◽

Closed String ◽

Bosonic String ◽

Loop Level ◽

The One ◽

String Theories

Quantum consistency of open string theories is considered at the one-loop level, using a unified and consistent regularization of all divergences. Finiteness of all amplitudes with open string states is shown to be possible for any SO (n) or USp (n) gauge group. Two consequences of the nonunitarity of tachyonic theories are discussed; the presence of unphysical cuts in amplitudes and the nondecoupling of null states. If not for contributions of the open string tachyon, decoupling of all null open bosonic string states would be obtained for SO (2D/2) independently of the regularization, corresponding to vanishing tadpoles of unphysical closed string states.

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On the quantization of folded strings in non-critical dimensions

Journal of High Energy Physics ◽

10.1007/jhep12(2020)120 ◽

2020 ◽

Vol 2020 (12) ◽

Author(s):

Jacob Sonnenschein ◽

Dorin Weissman

Keyword(s):

Scalar Curvature ◽

Space Dimension ◽

Massive Particle ◽

Open String ◽

Closed String ◽

Target Space ◽

Critical Dimensions ◽

Complete Set ◽

Rotating String ◽

Folding Point

Abstract Classical rotating closed string are folded strings. At the folding points the scalar curvature associated with the induced metric diverges. As a consequence one cannot properly quantize the fluctuations around the classical solution since there is no complete set of normalizable eigenmodes. Furthermore in the non-critical effective string action of Polchinski and Strominger, there is a divergence associated with the folds. We overcome this obstacle by putting a massive particle at each folding point which can be used as a regulator. Using this method we compute the spectrum of quantum fluctuations around the rotating string and the intercept of the leading Regge trajectory. The results we find are that the intercepts are a = 1 and a = 2 for the open and closed string respectively, independent of the target space dimension. We argue that in generic theories with an effective string description, one can expect corrections from finite masses associated with either the endpoints of an open string or the folding points on a closed string. We compute explicitly the corrections in the presence of these masses.

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KLT factorization of winding string amplitudes

Journal of High Energy Physics ◽

10.1007/jhep06(2021)057 ◽

2021 ◽

Vol 2021 (6) ◽

Author(s):

Jaume Gomis ◽

Ziqi Yan ◽

Matthew Yu

Keyword(s):

Scattering Amplitudes ◽

Open String ◽

Closed String ◽

Open Strings ◽

Toroidal Compactifications ◽

Quantum Numbers ◽

String Amplitudes

Abstract We uncover a Kawai-Lewellen-Tye (KLT)-type factorization of closed string amplitudes into open string amplitudes for closed string states carrying winding and momentum in toroidal compactifications. The winding and momentum closed string quantum numbers map respectively to the integer and fractional winding quantum numbers of open strings ending on a D-brane array localized in the compactified directions. The closed string amplitudes factorize into products of open string scattering amplitudes with the open strings ending on a D-brane configuration determined by closed string data.

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Minkowski box from Yangian bootstrap

Journal of High Energy Physics ◽

10.1007/jhep04(2021)160 ◽

2021 ◽

Vol 2021 (4) ◽

Author(s):

Luke Corcoran ◽

Florian Loebbert ◽

Julian Miczajka ◽

Matthias Staudacher

Keyword(s):

Minkowski Space ◽

Wigner Function ◽

Functional Form ◽

A Priori ◽

Alternative Methods ◽

Feynman Integrals ◽

The One

Abstract We extend the recently developed Yangian bootstrap for Feynman integrals to Minkowski space, focusing on the case of the one-loop box integral. The space of Yangian invariants is spanned by the Bloch-Wigner function and its discontinuities. Using only input from symmetries, we constrain the functional form of the box integral in all 64 kinematic regions up to twelve (out of a priori 256) undetermined constants. These need to be fixed by other means. We do this explicitly, employing two alternative methods. This results in a novel compact formula for the box integral valid in all kinematic regions of Minkowski space.

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Noncommutativity of closed string zero modes

Physical Review D ◽

10.1103/physrevd.96.066003 ◽

2017 ◽

Vol 96 (6) ◽

Cited By ~ 12

Author(s):

Laurent Freidel ◽

Robert G. Leigh ◽

Djordje Minic

Keyword(s):

Closed String ◽

Zero Modes

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Does the HM mechanism work in string theory?

Canadian Journal of Physics ◽

10.1139/cjp-2012-0163 ◽

2013 ◽

Vol 91 (1) ◽

pp. 75-80

Author(s):

Alireza Sepehri ◽

Somayyeh Shoorvazi ◽

Mohammad Ebrahim Zomorrodian

Keyword(s):

Hilbert Space ◽

Black Hole ◽

String Theory ◽

Correspondence Principle ◽

Black Hole Entropy ◽

Closed String ◽

Centre Of Mass ◽

Final State ◽

Information Transformation ◽

Left And Right

The correspondence principle offers a unique opportunity to test the Horowitz and Maldacena mechanism at the correspondence point “the centre of mass energies around (Ms/(gs)2)”. First by using the Horowitz and Maldacena proposal, the black hole final state for closed strings is studied and the entropy of these states is calculated. Then, to consider the closed string states, a copy of the original Hilbert space is constructed with a set of creation–annihilation operators that have the same commutation properties as the original ones. The total Hilbert space is the tensor product of the two spaces Hright ⊗ Hleft, where in this case Hleft/right denote the physical quantum state space of the closed string. It is shown that closed string states can be represented by a maximally entangled two-mode squeezed state of the left and right spaces of closed string. Also, the entropy for these string states is calculated. It is found that black hole entropy matches the closed string entropy at transition point. This means that our result is consistent with correspondence principle and thus HM mechanism in string theory works. Consequently the unitarity of the black hole in string theory can be reconciled. However Gottesman and Preskill point out that, in this scenario, departures from unitarity can arise due to interactions between the collapsing body and the infalling Hawking radiation inside the event horizon and information can be lost. By extending the Gottesman and Preskill method to string theory, the amount of information transformation from the matter to the state of outgoing Hagedorn radiation for closed strings is obtained. It is observed that information is lost for closed strings.

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