On Gauge Invariant Cosmological Perturbations in UV-modified Horava Gravity: A Brief Introduction

We revisit gauge invariant cosmological perturbations in UV-modified, z = 3 Horava gravity with one scalar matter field, which has been proposed as a renormalizable gravity theory without the ghost problem in four dimensions. We confirm that there is no extra graviton modes and general relativity is recovered in IR, which achieves the consistency of the model. From the UV-modification terms which break the detailed balance condition in UV, we obtain scale-invariant power spectrums for non-inflationary backgrounds, like the power-law expansions, without knowing the details of early expansion history of Universe. This could provide a new framework for the Big Bang cosmology.Comment: 5 pages, Prepared for Proceeding of International Joint Conference of ICGAC-XIII and IK15 (July 3-7, 2017, Seoul, Republic of Korea

A Note on Multi-Issue Bargaining with a Finite Set of Alternatives

We study two bilateral multi-issue bargaining procedures with complete information and endogenous agenda, where each issue is associated with a finite set of alternatives. In both procedures, when bargaining frictions are small, we find a large multiplicity of equilibrium agreements, including ones with arbitrarily long delays. Thus, this paper extends the previous results of van Damme et al. (1990) and Muthoo (1991) for the single-issue case to multi-issue cases. Furthermore, we show that in the first procedure (issue-by-issue bargaining), the stationary subgame perfect equilibria alone may support a large multiplicity of inefficient agreements. Confronting a recent study, this implies that it is not necessary to appeal to “strictly controversial” issues in a bargaining problem in order to find multiplicity and delay in agreements.multi-issue bargaining, finiteness of alternatives, multiple equilibria, inefficiency and delay

A Fictitious-Play Model of Bargaining To Implement the Nash Solution

We present a fictitious-play model of bargaining, where two bargainers play the Nash demand game repeatedly. The bargainers make a deliberate decision on their demands in the initial period and then follow a fictitious play process subsequently. If the bargainers are patient, the set of epsilon -equilibria of the initial-demand game is in a neighborhood of the division corresponding to the Nash bargaining solution. As the bargainers make a more accurate comparison of payoffs and become more patient accordingly, the set of epsilon-equilibria shrinks and the only equilibrium left is the division of the Nash bargaining solution.fictitious play, Nash demand game, epsilon-equilibrium, Nash bargaining solution, Nash program.