Non-Abelian Gauge Theory on q-Quantum Spaces

Gauge theories on q-deformed spaces are constructed using covariant derivatives. For this purpose a ``vielbein'' is introduced, which transforms under gauge transformations. The non-Abelian case is treated by establishing a connection to gauge theories on commutative spaces, i.e. by a Seiberg-Witten map. As an example we consider the Manin plane. Remarks are made concerning the relation between covariant coordinates and covariant derivatives.Comment: 17 pages, Late

Enveloping algebra valued gauge transformations for non-abelian gauge groups on non-commutative spaces

An enveloping algebra valued gauge field is constructed, its components are functions of the Lie algebra valued gauge field and can be constructed with the Seiberg-Witten map. This allows the formulation of a dynamics for a finite number of gauge field components on non-commutative spaces.Comment: 13 page

External Fields as Intrinsic Geometry

There is an interesting dichotomy between a space-time metric considered as external field in a flat background and the same considered as an intrinsic part of the geometry of space-time. We shall describe and compare two other external fields which can be absorbed into an appropriate redefinition of the geometry, this time a noncommutative one. We shall also recall some previous incidences of the same phenomena involving bosonic field theories. It is known that some such theories on the commutative geometry of space-time can be re-expressed as abelian-gauge theory in an appropriate noncommutative geometry. The noncommutative structure can be considered as containing extra modes all of whose dynamics are given by the one abelian action.Comment: 19 pages, Late

Loss of control vs. risk reduction: decision factors for hiring non-family CFOs in family firms

Objectives: We examine decision factors of family firm owners for hiring a non-family Chief Financial Officer (CFO). We explore the perceptions of family firm owners towards external managers by analyzing how their family-specific and company-specific goals relate to the employment of a non-family CFO. Furthermore, we analyze the consequences of hiring a non-family CFO on financial policies such as the use of strategic financial plans and initiatives to improve relationships with external capital providers. Prior work: Prior research has acknowledged that the attitude to external managers is a major concern for family firms because of potential problems due to a separation of ownership and management. However, it was shown that non-family CFOs positively influence the operational performance of privately-held family firms. Little knowledge exists to date to explicitly link the decision to hire an external CFO to the goals of family firm owners. Approach: Our study is based on a survey of 237 small- and medium-sized privately-held German family firms in 2007. We use logistic regression analysis to test our theory-driven hypotheses on the relationship between family-specific as well as company-specific goals of the family and the employment of a non-family CFO. Furthermore, we use OLS and logistic regression analysis to analyze hypotheses on how non-family CFOs influence financial policies. Results: The results suggest that family firm owners are reluctant to hire non-family CFOs because of agency type of problems. They decide against an external CFO when their goal of independence and control is high. Furthermore, they do not seem to trust external managers to act in accordance to their goal of enterprise value growth. However, they seem to realize that non-family CFOs are likely to decrease financial risk through the provision of additional capabilities. Non-family CFOs are shown to influence financial policies and, thereby, to bring in value creating resources. Implications: Family firm owners can use the results to understand the relevant factors they should consider when employing an external CFO. In particular, they should focus on establishing incentive structures for external managers to follow goals of the family. Candidates for non-family CFOs are able to better comprehend the underlying objectives of family firm owners in the hiring decision. Value: Our findings are relevant to further disentangle the relationship between external managers and family firm owners. By applying both the agency theory and the resource based view, we are able to offer explanations for and against the decision to hire non-family CFOs in family firms. --CFO,family firms,financial policy,entrepreneurial finance,corporate governance

Private equity minority investments in large family firms: what influences the attitude of family firm owners?

This paper extends research in the field of private equity investments in family firms. It contributes to the literature by fundamentally analyzing the decision criteria of family firm owners for using minority investments of private equity investors. This type of financing might be of great interest to family firms, as the family firm owner is able to secure majority ownership and control over the family business. Likewise, minority investments might be attractive for private equity investors, as they are mostly not leveraged and therefore independent from capital market turbulences. Using data from 21 case studies, we identify challenges induced by the family or the business that lead to the phenomenon of private equity minority investments in family firms. We find that perceived benefits and drawbacks of private equity investments are influenced by business and family characteristics. Based on pecking-order theory, resource-based view and the strategy paradigm, propositions as well as a conceptual framework are developed. --private equity,minority investments,family firms,financing,managerial resources

Quantitative valuation of platform technology based intangibles companies

In the course of raising external equity, e.g. from venture capitalists, a quantitative valuation is usually required for entrepreneurial ventures. This paper examines the challenges of quantitatively valuing platform technology based entrepreneurial ventures. The distinct characteristics of such companies pose specific requirements on the applicability of quantitative valuation methods. The entrepreneur can choose from a wide range of potential commercialization strategies to pursue in the course of company development which is difficult to take account of in a quantitative valuation. By developing and applying a systematic map of valuation requirements in this context, we analyze whether the cost, market or income approach is suitable for platform technology based entrepreneurial ventures. We argue that all three valuation methods have drawbacks. Yet, the income approach fulfills most of the requirements and, therefore, is considered to be more suitable for the entrepreneur as well as external equity providers than other quantitative valuation methods. --entrepreneurial venture,platform technology,young venture valuation,quantitative company valuation,intangible assets,intellectual property,commercialization strategies,value extraction

Realization of the Three-dimensional Quantum Euclidean Space by Differential Operators

The three-dimensional quantum Euclidean space is an example of a non-commutative space that is obtained from Euclidean space by $q$-deformation. Simultaneously, angular momentum is deformed to $so_q(3)$, it acts on the $q$-Euclidean space that becomes a $so_q(3)$-module algebra this way. In this paper it is shown, that this algebra can be realized by differential operators acting on $C^{\infty}$ functions on $\mathbb{R}^3$. On a factorspace of $C^{\infty}(\mathbb{R}^3)$ a scalar product can be defined that leads to a Hilbert space, such that the action of the differential operators is defined on a dense set in this Hilbert space and algebraically self-adjoint becomes self-adjoint for the linear operator in the Hilbert space. The self-adjoint coordinates have discrete eigenvalues, the spectrum can be considered as a $q$-lattice.Comment: 13 pages, late

Longevity & Healthspan / From cellular senescence to age-associated diseases: the miRNA connection

Cellular senescence has evolved from an in-vitro model system to study aging in vitro to a multifaceted phenomenon of in-vivo importance as senescent cells in vivo have been identified and their removal delays the onset of age-associated diseases in a mouse model system. From the large emerging class of non-coding RNAs, miRNAs have only recently been functionally implied in the regulatory networks that are modified during the aging process. Here we summarize examples of similarities between the differential expression of miRNAs during senescence and age-associated diseases and suggest that these similarities might emphasize the importance of senescence for the pathogenesis of age-associated diseases. Understanding such a connection on the level of miRNAs might offer valuable opportunities for designing novel diagnostic and therapeutic strategies