A New Contact Paradox

The Painleve paradox in contact mechanics

The 120-year old so-called Painlevé paradox involves the loss of determinism in models of planar rigid bodies in point contact with a rigid surface, subject to Coulomb-like dry friction. The phenomenon occurs due to coupling between normal and rotational degrees-of-freedom such that the effective normal force becomes attractive rather than repulsive. Despite a rich literature, the forward evolu...

A New Version of Edgeworth’s Taxation Paradox

Edgeworth’s taxation paradox states that an excise tax can decrease the market price of a good. This paper presents a new version of the paradox in which a tax reduces price because it attracts entry of additional …rms into the market. The paper also presents two new applications: (i) an emissions tax that leads to an increase in industry emissions (due to entry), and (ii) an interest rate cut ...

Bargaining in Legislatures: A New Donation Paradox

It is well known that proposers have an advantage in the canonical model of bargaining in legislatures: proposers are sure of being part of the coalition that forms, and, conditional on being in a coalition, a player receives more as a proposer than as a coalition partner. In this paper I show that, if parties di¤er in voting weight, it is possible for a party to donate part of its proposing pr...

Explaining mutualism variation: a new evolutionary paradox?

The paradox of mutualism is typically framed as the persistence of interspecific cooperation, despite the potential advantages of cheating. Thus, mutualism research has tended to focus on stabilizing mechanisms that prevent the invasion of low-quality partners. These mechanisms alone cannot explain the persistence of variation for partner quality observed in nature, leaving a large gap in our u...

A New Paradox in Type Theory