4,323 research outputs found
Proton Decay Constraints on Low Scale AdS/CFT Unification
Dark matter candidates and proton decay in a class of models based on the
AdS/CFT correspondence are discussed. We show that the present bound on the
proton decay lifetime is inconsistent with SUSY, and strongly
constrains non-SUSY, low scale trinification type unification of
orbifolded AdS models.Comment: 10 page
Collisional Processes in Extrasolar Planetsimal Disks - Dust Clumps in Fomalhaut's Debris Disk
This paper presents a model for the outcome of collisions between
planetesimals in a debris disk and assesses the impact of collisional processes
on the structure and size distribution of the disk. The model is presented by
its application to Fomalhaut's collisionally replenished dust disk; a recent
450 micron image of this disk shows a clump embedded within it with a flux ~5
per cent of the total. The following conclusions are drawn: (i) SED modelling
is consistent with Fomalhaut's disk having a collisional cascade size
distribution extending from bodies 0.2 m in diameter down to 7 micron-sized
dust. (ii) Collisional lifetime arguments imply that the cascade starts with
planetesimals 1.5-4 km in diameter. Any larger bodies must be predominantly
primordial. (iii) Constraints on the timescale for the ignition of the cascade
are consistent with these primordial planetesimals having a distribution that
extends up to 1000km, resulting in a disk mass of 5-10 times the minimum mass
solar nebula. (iv) The debris disk is expected to be intrinsically clumpy,
since planetesimal collisions result in dust clumps. The intrinsic clumpiness
of Fomalhaut's disk is below current detection limits, but could be detectable
by future observatories such as the ALMA, and could provide the only way of
determining the primordial planetesimal population. (v) The observed clump
could have originated in a collision between two runaway planetesimals, both
larger than 1400 km diameter. It is unlikely that we should witness such an
event unless both the formation of these runaways and the ignition of the
collisional cascade occurred within the last ~10 Myr. (vi) Another explanation
for Fomalhaut's clump is that ~5 per cent of the planetesimals in the ring are
trapped in 1:2 resonance with a planet orbiting at 80 AU.Comment: 21 pages, 13 figures, accepted by MNRA
Minimal Pati-Salam Model from String Theory Unification
We provide what we believe is the minimal three family SUSY
and conformal Pati-Salam Model from type IIB superstring theory. This
orbifolded AdS model has long lived protons and has potential
phenomenological consequences for LHC.Comment: 8 page
The Revolution in Corporate Governance, The Monitoring Board, and The Director\u27s Duty of Care
The theory of corporate governance underwent a revolution in the 1970\u27s. Theorists finally abandoned the myth that a public corporation\u27 is managed by its board of directors, and constructed a new model under which the corporation is managed by its executive officers, and the board, dominated by outside directors, monitors management\u27s performance. This new monitoring model has gained wide acceptance among commentators, and several of its elements have been adopted by many public corporations. Even those commentators who do not enthusiastically embrace the entire monitoring model tend to agree that monitoring management is a significant board function.
But expositions of the monitoring model to date have been rudimentary. Its proponents have not suggested what forces will prompt corporations to adopt the model and thereby move it from theory to widely accepted reality. Nor have they described in detail what the board\u27s duties would be under the model, much less how these duties would be discharged. Until these problems are satisfactorily resolved, the potential of the monitoring model for improving corporate governance must be considered an open question.
This Article grapples with these problems. In exploring the possible mechanisms for enforcing adoption of and performance under the monitoring model, the Article concludes that market forces alone will not suffice and that legislative solutions face insuperable political and theoretical obstacles.6 Accordingly, special attention is given to the duty of care of directors and officers as a possible enforcement mechanism. The duty of care has been a problem child of corporate law. Its command that directors and officers perform their duties with reasonable prudence appears on its face to provide a significant constraint on directors and officers, especially in an age when control has become divorced from ownership in public corporations.7 In practice, however, the duty of care has proved almost totally ineffectual.8 A key question concerning the monitoring model, then, is what will be the content of the duty of care given the new role of the director that the model envisions and, more particularly, whether the duty of care can be revived and used as a tool for enforcing the monitoring model
Unprofitable Mergers: Toward a Market-Based Legal Response
The reams of commentary on corporate mergers, acquisitions, and tender offers have focused largely on protection of shareholders of acquired (or target) companies from both the depredations of acquiring (or raider) companies and the cupidity of their own managements in either negotiating the terms or obstructing the accomplishment of transactions. Virtually no attention has been paid to the plight of shareholders of acquiring companies devastated by unwise acquisitions. This oversight is surprising: some acquisitions have been spectacular disasters, destroying hundreds of millions of dollars in the value of the acquiring company\u27s stock.1 Nor are these isolated cases: on average, acquisitions produce little or no gain for acquiring companies.2 A few commentators have recommended eradicating unprofitable acquisitions by requiring approval of the acquirer\u27s shareholders, altering the accounting treatment of mergers, or enjoining conglomerate mergers. Close analysis shows that these proposals would not solve the problem. This Article proposes instead a response based on the most reliable index of the profitability of an acquisition-the reaction of the acquirer\u27s stock price
The George A. Leet Business Law Symposium: The Role of Lawyers in Strategic Alliances - Introduction
Introducation to The George A. Leet Business Law Symposium: The Role of Lawyers in Strategic Alliances, Cleveland, Ohio
Proxy Regulation in Search of a Purpose
Changing conditions often force us to rethink the role of a law. Professor Ryan\u27s scholarly article, Rule 14a-8, Institutional Shareholder Proposals, and Corporate Democracy,underscores this need. His article is useful for both its successes and its failures. Its principal failure is its inability to identify a general justification for the rule. This is helpful; the failure of an intelligent and deter- mined advocate to find a persuasive defense of the rule confirms that no defense is possible. The article succeeds principally in showing how institutional investors have recently used the rule in ways that put the rule in a new light. The new developments demand a response from the rule\u27s critics. This reply argues that Professor Ryan is right in concluding that the new developments justify a role for the rule, but that this role must be more narrowly defined than it has been by Professor Ryan
Dual Class Capitalization: A Reply to Professor Seligman
Professor Joel Seligman\u27s article, Equal Protection in Share- holder Voting Rights: The One Common Share, One Vote Contro- versy,\u27 is an impressive accomplishment in many respects. It confirms his status as premier historian of our securities laws and markets.2 It also provides a powerful analysis of, and the first se- rious argument against, dual class capitalization, and proposes a thoughtful solution to the problems it raises. Despite these formi- dable assets, some of Professor Seligman\u27s conclusions are debata- ble. First, Professor Seligman argues that the Securities and Exchange Commission (SEC) can impose on the National Associa- tion of Securities Dealers (NASD) and the stock exchanges (col- lectively, the securities markets ) rules forbidding dual class common stock among companies listed for trading.3 Further, Pro- fessor Seligman argues that such rules would be wise.4
This Reply argues that both his positions are ill-founded. Part I analyzes the SEC\u27s power to forbid dual class capitalization. Part II discusses the concept of efficiency in corporate law and proce- dural safeguards to limit dual class capitalization to situations in which it is efficient. It further provides a theoretical discussion of the efficiency of dual class capitalization. Part III advances a counterproposal to Professor Seligman\u27s position, as well as that of Professor Daniel Fischel. Although Professor Seligman is right that dual class capitalization creates dangers, new legislation can allow such capitalization, yet protect against these dangers. Un- like his proposed prohibition, this new legislation should permit dual class stock if it will not injure public shareholders
Limited Liability in Environmental Law
The social importance and immense costs of pollution make environmental law an ideal arena for reconsidering theories of limited liability for tort. This article examines the question in the context of the Comprehensive Environmental Response, Compensation, and Liability Act (CER-CLA).1 Part I reviews the text and legislative history of the Act. Part II analyzes the CERCLA case law on the liability of controlling persons, especially those involving parent corporations. Part III discusses the general theory of limited liability and its exceptions. Part IV applies this general theory to CERCLA and finds that its special features call for distinctive approaches. Part V advocates an approach to controlling person liability that furthers the purposes of the Act without impairing other important policies
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