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Tuominen, K

Publications and source records attributed to Tuominen, K.

Mass spectrum and thermodynamics of quasiconformal gauge theories from gauge/gravity duality

We use gauge/gravity duality to study simultaneously the mass spectrum and the thermodynamics of a generic quasiconformal gauge theory, specified by its beta function. The beta function of a quasiconformal theory almost vanishes, and the coupling is almost constant between two widely separated energy scales. Depending on whether the gravity dual has a black hole or not, the mass spectrum is either a spectrum of quasinormal oscillations or a normal T=0 mass spectrum. The mass spectrum is quantitatively correlated with the thermal properties of the system. As the theory approaches conformality, the masses have to vanish. We show that in this limit, the masses calculated via gauge/gravity duality satisfy expected scaling properties.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗

Resizing the conformal window: A {beta}-function ansatz

We propose an ansatz for the nonperturbative beta-function of a generic nonsupersymmetric Yang-Mills theory with or without fermions in an arbitrary representation of the gauge group. While our construction is similar to the recently proposed Ryttov-Sannino all-order beta-function, the essential difference is that it allows for the existence of an unstable ultraviolet fixed point in addition to the predicted Banks-Zaks-like infrared stable fixed point. Our beta-function preserves all of the tested features with respect to the nonsupersymmetric Yang-Mills theories. We predict the conformal window identifying the lower end of it as a merger of the infrared and ultraviolet fixed points.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗