Dynamical Cobordism and the Beginning of Time: Supercritical Strings and Tachyon Condensation

Abstract

We describe timelike linear dilaton backgrounds of supercritical string theories as time-dependent Dynamical Cobordisms in string theory, with their spacelike singularity as a boundary defining the beginning of time. We propose and provide compelling evidence that its microscopic interpretation corresponds to a region of (a strong coupling version of) closed tachyon condensation. We argue that this beginning of time is closely related to (and shares the same scaling behaviour as) the bubbles of nothing obtained in a weakly coupled background with lightlike tachyon condensation. As an intermediate result, we also provide the description of the latter as lightlike Dynamical Cobordism.

23 pages + appendices

References in corpus (13)

• On the Geometry of the String Landscape and the Swampland
• Cosmological solutions of supercritical string theory
• 8d Supergravity, Reconstruction of Internal Geometry and the Swampland
• Dimension-changing exact solutions of string theory
• Big Bang Models in String Theory
• On the Swampland Cobordism Conjecture and Non-Abelian Duality Groups
• Charting the landscape of supercritical string theory
• Dynamical Tadpoles, Stringy Cobordism, and the SM from Spontaneous Compactification
• New Dimensions for Wound Strings: The Modular Transformation of Geometry to Topology
• Cosmological unification of string theories
• Cosmology of the closed string tachyon
• Dimensional Duality
• Heterotic NS5-branes from closed string tachyon condensation

Cited by in corpus (11)

• Dynamical Cobordism Conjecture: Solutions for End-of-the-World Branes
• Emergence of Species Scale Black Hole Horizons
• IIB Explored: Reflection 7-Branes
• On the Origin of Species Thermodynamics and the Black Hole - Tower Correspondence
• Revisiting Dudas-Mourad compactifications
• Small Black Hole Explosions
• Dimensional Reduction of Cobordism and K-theory
• Hitchhiker's Guide to the Swampland: The Cosmologist's Handbook to the string-theoretical Swampland Programme
• Morse-Bott inequalities, Topology Change and Cobordisms to Nothing
• Gravitational Background of Alice-Vortices and R7-Branes
• Heterotic Ouroboros