9,265 research outputs found
Regularity of Eigenstates in Regular Mourre Theory
The present paper gives an abstract method to prove that possibly embedded
eigenstates of a self-adjoint operator lie in the domain of the
power of a conjugate operator . Conjugate means here that and have a
positive commutator locally near the relevant eigenvalue in the sense of
Mourre. The only requirement is regularity of . Regarding
integer , our result is optimal. Under a natural boundedness assumption of
the multiple commutators we prove that the eigenstate 'dilated' by
is analytic in a strip around the real axis. In particular,
the eigenstate is an analytic vector with respect to . Natural applications
are 'dilation analytic' systems satisfying a Mourre estimate, where our result
can be viewed as an abstract version of a theorem due to Balslev and Combes. As
a new application we consider the massive Spin-Boson Model.Comment: 27 page
Network Models
Networks can be combined in various ways, such as overlaying one on top of
another or setting two side by side. We introduce "network models" to encode
these ways of combining networks. Different network models describe different
kinds of networks. We show that each network model gives rise to an operad,
whose operations are ways of assembling a network of the given kind from
smaller parts. Such operads, and their algebras, can serve as tools for
designing networks. Technically, a network model is a lax symmetric monoidal
functor from the free symmetric monoidal category on some set to
, and the construction of the corresponding operad proceeds via a
symmetric monoidal version of the Grothendieck construction.Comment: 46 page
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You can make the jump, but can you stick the landing? Private equity goes international
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M&A Attractiveness Index 2017: Russia: Count the Roubles Not the Politics
An invasion of the Crimea, interference in the Ukraine, a large list of companies blacklisted overseas, concerns over the openness of the next election and accusations of interference in the US presidential election. Not a good time to invest in Russia then. But Russia is a country of vast natural resources, is the world’s largest nation by geographic site, has a large population (144 million) and has one of the cheapest stock markets in the world (trading on just 7x historic earnings). So, do the latter attractions outweigh the opening issues?
This report investigates the relationship between changes in political risk levels and the long-term success of cross-border acquisitions in Russia
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'Hedge Funds: Stock Pickers or Managers?
For decades, corporate managers have criticised analysts, fund managers, hedge fund managers and private equity professionals for telling them how to run their business, wihout having had the necessary experience. Now hedge fund activists are regularly suggesting operational decisions, and in some cases even in areas traditionally reserved for management. ‘Activism has gone from being frowned upon, something that marks you out as a rogue or maverick, to almost socially responsible.’1 These hedge funds may have become an accepted part of the governance universe but are they actually adding value?
Recent studies have answered this question in the affirmative, but what if those companies picked out by hedge funds for their attention were already on their way to outperformance? The observed outperformance may not be due to a hedge fund’s ability to contribute to value creation but a mere reflection of their stock picking abilities. The difficulty is in identifying those companies that would have made typical hedge fund targets but which were not actually targeted, i.e. build an appropriate group of comparable companies. We have developed a statistical model to identify just these companies
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Deal closure is the starting point not the end point
Mergers and Acquisitions (M&A) as a growth strategy has been intensely debated, but recent studies suggest that companies that are ‘inactive’ in terms of M&A are underperforming their more active peers, meaning executives need to consider these opportunities.
As executives turn to M&A to deliver the expected growth, companies need to develop their own repeatable methodologies for dealing with the different phases of a transaction to reduce business risk and costs and maintain consistency with how M&A projects are executed. In addition a company well regarded in M&A execution will be rewarded by the market with a greater capacity to finance further M&A.
This report by Mergers and Acquisitions Research Centre (MARC) at Cass Business School with the collaboration of Willis Towers Watson seeks to uncover how a group of serial acquirers has overcome challenges posed by multiple acquisitions and what challenges they still face
Genetic Aspects of Female Longevity
Longevity of the breeding female has both economic and animal welfare implications for the swine industry. High culling levels lead to increased replacement rates and reduce lifetime productivity for individual breeding females and the breeding herd. Greater replacement rates increase production costs related to purchase (or development), isolation, and acclimation of replacement females. PigCHAMP [1-5] summaries (Table 1) from 1998 through 2003, report annualized replacement rates of \u3e 50% and average herd parity of only 2.5 litters. Breeding herd productivity and economic sustainability are compromised when females are culled early in life and prior to achieving a positive return on investment. Breeding program design and genetic selection decisions clearly influence sow longevity and establish the base for a profitable, sustainable breeding herd
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