Higgs Inflation and the Refined dS Conjecture

The refined de Sitter derivative conjecture provides constraints to potentials that are low energy effective theories of quantum gravity. It can give direct bounds on inflationary scenarios and determine whether the theory is in the Landscape or the Swampland. We consider the `Higgs inflation' scenario taking the refined de Sitter derivative conjecture into account. Obtaining the critical lines for the potential, we find a conjecture parameter space in which the `Higgs inflation' is to be in the Landscape. Comparing with the model independent observational bounds from recent data we find that the observational bounds represent the Higgs inflation can be in the Landscape.Comment: 5 pages, 4 figures, Version to appear in PL

Doctor of Philosophy

dissertationParrondo games with spatial dependence have been studied by Ethier and Lee. More precisely, they studied Toral's Parrondo games with N players arranged in a circle. The players play either game A or game B. In game A, a randomly chosen player wins or loses one unit according to the toss of a fair coin. In game B, which depends on parameters p0; p1; p2; p3 2 [0; 1], a randomly chosen player wins or loses one unit according to the toss of a pm-coin, where m 2 f0; 1; 2; 3g depends on the winning or losing status of the player's two nearest neighbors. In this dissertation, we study a spatially dependent game A, which we call game A0, introduced by Xie and others and considered by Ethier and Lee. Noting that game A0 is fair, we say that the Parrondo e#11;ect occurs if game B is losing or fair and the random mixture C0 := A0 + (1 -y )B [respectively, the nonrandom periodic pattern C0 := (A0)rBs] is winning. With p1 = p2 and the parameter space being the unit cube, we investigate numerically the region in which the Parrondo e#11;ect appears. We give su#14;cient conditions for the ergodicity of an interacting particle system in f0; 1gZ corresponding to the random mixture C0 := A0+(1-y )B by applying a theorem of Liggett, and also by means of \annihilating duality". We also show that limN!1 #22;N ( ;1-y )0 and limN!1 #22;N [r;s]0 exist under certain conditions, where #22;N ( ;1-y )0 denotes the mean pro#12;t per turn at equilibrium to the N players playing the random mixture C0 := A0 + (1-y )B, and #22;N [r;s]0 denotes the mean pro#12;t per turn at equilibrium to the N players playing the nonrandom periodic pattern C0 := (A0)rBs

Programmable Matter Research based on 4D printing

Department of Materials Science EngineeringAs a concept suggested by Skylar Tibbits of MIT in 2013, 4D printing is a field with many new possibilities. 4D printing produces programmable matter that responds to exterior stimuli and changes its structure or properties into the shape designed in advance, through 3D printing. One of the advantages of 4D printing is that a motion can be realized in a simple constitution in order for a certain material to move even without a complicated driving mechanism like a motor. This paper first explains 3D printing and 4D printing and then deals with 4D printing using the properties of Poly-Lactic Acid (PLA), which is a shape memory polymer, and 4D printing using a bistable structure. In the case of 4D printing using PLA, we applied the properties that the shape is restored to the original form at a state higher than glass temperature to 3D printing and tested what structure of 4D printing would be possible in the future. In the case of the bistable structure, we made the basic elements of a mechanical bistable structure in order for 4D printing using Shape Memory Polymer (SMP) to produce more efficiently, and prepared the ground that can realize the diversified and complicated mechanical movements.ope