We review recent work in which compactifications of string and M theory are constructed in which all scalar fields (moduli) are massive, and supersymmetry is broken with a small positive cosmological constant, features needed to reproduce real world physics. We explain how this work implies that there is a “landscape” of string/M theory vacua, perhaps containing many candidates for describing r...

These are notes for a graduate seminar on perverse sheaves.

This article discusses unexpected consequences of idealistic conceptions about the modernization of power grids. We will focus our analysis on demand-response policies based on automatic decisions by the so-called smart home appliances. Following the usual design approach, each individual appliance has access to a universal signal (e.g. grid frequency or electricity price) that is believed to i...

This paper enquires into the nature of the act of communication between two or more persons. It proposes that such acts are best conceived of as moral, as related to the performative consequences of the acts in question. Given this, the paper then asks what applicability phrases like ‘overload’ might have, and whether quantitative techniques have a role other than as a heuristic in understandin...

We estimate the effect of a price floor regulation implemented in the Canadian province of Quebec beginning in 1997 and find that it substantially reduced the entry and exit of stations in local Quebec markets. We show that as a result of the policy, competition was higher and prices were lower in Quebec compared with a control group of unregulated markets in the neighboring province of Ontario...

In this paper, using data from a set of exploratory interviews, we inductively develop an integrative framework identifying key enablers and inhibitors that influence the process of use and adoption of hybrid wireless devices by subjects who participated in threeweek long trial studies. A number of intended as well as unintended consequences of the use and adoption of the technology also emerge...

The Belgian railway network has a high traffic density with Brussels as its gravity center. The star-shape of the network implies heavily loaded bifurcations in which knock-on delays are likely to occur. Knock-on delays should be minimized to improve the total punctuality in the network. Based on experience, the most critical junctions in the traffic flow are known, but others might be hidden. ...

This paper discusses how the effects of taxes on economic behavior are important for revenue estimation, for calculating efficiency effects, and for understanding short-term macroeconomoic consequences. The primary focus is on taxes on labor income but some attention is given to taxes on income from saving. Specific calculations illustrate the importance of behavioral responses for accurate cal...

The relationship between a product and its design process is generally complex and not fully understood. When modifying a product, industry still rarely considers the implementation process and its consequences for other design activities in the company, which is hard to assess with conventional planning methods. Although change processes are highly constrained, product and process constraints ...

Biological invasions are an economic problem. Invasions are typically the intended or unintended consequence of economic activity. They impose real costs on society, and the risk of invasion depends on human behaviour. Effective control of invasions depends on using the right economic instruments and developing the right institutions. The problem has two special features. The first is that the ...