389 research outputs found
Free Energies and Probe Actions for Near-horizon D-branes and D1 + D5 System
By working with the free energy for the type II supergravity near-horizon
solution of N coincident non-extremal Dp-branes we study the transitions among
the non-conformal Dp-brane system, the perturbative super Yang-Mills theory and
a certain system associated with M theory. We derive a relation between this
free energy and the action of a Dp-brane probe in the N Dp-brane background.
Constructing the free energy for the five dimensional black hole labeled by the
D1-brane and D5-brane charges we find the similar relation between it and the
action of a D1 or D5 brane probe in the D1 + D5 brane background. These
relations are explained by the massive open strings stretched between the
relevant D-branesComment: 14 pages, LaTeX2e, no figure
IMPACT OF HEALTH INFORMATION ON DEMAND FOR FATS AND OILS IN JAPAN: COINTEGRATION AND A COMPLETE DEMAND SYSTEM APPROACH
This paper deals with the structural change for fats and oils in Japan focusing on the possible influence of health information. The newly developed fat and cholesterol information index appears to reflect the changing health information on fat and cholesterol much better than the ad-hoc cumulative index.Food Consumption/Nutrition/Food Safety,
Can urban agriculture contribute to well-being? An analytical perspective
Can agriculture improve the lives of urban citizens and the urban environment? This research explores this question by examining the impacts of urban agriculture on the lives of citizens and their environments through the notions of well-being and alienation. A Eudaimonic perspective of well-being is based on the idea that people feel happy if they experience purpose, growth and challenges in their lives. From a eudaimonic perspective, psychological well-being can be understood as encompassing six dimensions: self-acceptance, personal growth, environmental mastery, positive relationships with others, purpose of life and autonomy. Discourse on alienation begins with four dimensions as proposed by Marx: alienation from products, product activities, species beings and other fellows. De-alienation is discussed in relation to the tradition of alienation theory, which is grounded in both an American socialist and a neo-Marxist interpretation. By analysing the impacts of urban agriculture through the perspectives of eudaimonic well-being and alienation, the study suggests a theoretical bridge between the two, whereby their associations with urban agriculture shape a type of farming for the purposes of achieving de-alienation. The importance of this study is not just to examine urban agriculture, but also to emphasize its importance, especially with regard to the well-being of the community wherein it is practiced. Urban agriculture is not a comprehensive solution to the issues facing the future of cities in developing countries; however, it is an essential part of any program seeking to make these cities more liveable and to improve the lives of city dwellers. This thesis finally explores an exemplary form of urban agriculture for psychological well-being and de-alienation from the following perspectives: -Large-scale farming through communal farming and planning -Ecologically friendly farming -Long-term projects associated with public health -Agricultural programs that enhance participants’ mastery of agriculture by ensuring autonomy and environmental mastery
Three Spin Spiky Strings in beta-deformed Background
We study rigidly rotating strings in -deformed
background with one spin along AdS and two angular momenta along . We
find the spiky string solutions and present the dispersion relation among
various charges in this background. We further generalize the result to the
case of four angular momenta along .Comment: 12 pages, minor corrections, added references, to appear in JHE
Baryon Masses and Wilson Loops for Fractional D3-Branes on the Resolved Conifold
We study the IR dynamics of the type IIB supergravity solution describing N
D3-branes and M fractional D3-branes on the resolved conifold. The baryon mass
and the tension of domain wall in the dual gauge theory are evaluated and
compared with those for the deformed conifold. The IR behavior of the solution
for the general conifold is also discussed. We show that the area law behavior
of the Wilson loop is attributed to the existence of the locus in the IR where
the D3-brane charge vanishes.Comment: 13 pages, LaTeX2e, no figure
Infinite spin limit of semiclassical string states
Motivated by recent works of Hofman and Maldacena and Dorey we consider a
special infinite spin limit of semiclassical spinning string states in AdS5 x
S5. We discuss examples of known folded and circular 2-spin string solutions
and demonstrate explicitly that the 1-loop superstring correction to the
classical expression for the energy vanishes in the limit when one of the spins
is much larger that the other. We also give a general discussion of this limit
at the level of integral equations describing finite gap solutions of the
string sigma model and argue that the corresponding asymptotic form of the
string and gauge Bethe equations is the same.Comment: 38 pages, 3 figures; v2: comments on derivation of bound states of
magnons from discrete Bethe equations added in section 4 and appendix C,
references added, Imperial-TP-AT-6-4, HUTP-06/A002
Spiky strings and single trace operators in gauge theories
We consider single trace operators of the form O_{m_1 ... m_n} = tr D_+^{m_1}
F ... D_+^{m_n} F which are common to all gauge theories. We argue that, when
all m_i are equal and large, they have a dual description as strings with
cusps, or spikes, one for each field F. In the case of N=4 SYM, we compute the
energy as a function of angular momentum by finding the corresponding solutions
in AdS_5 and compare with a 1-loop calculation of the anomalous dimension. As
in the case of two spikes (twist two operators), there is agreement in the
functional form but not in the coupling constant dependence. After that, we
analyze the system in more detail and find an effective classical mechanics
describing the motion of the spikes. In the appropriate limit, it is the same
(up to the coupling constant dependence) as the coherent state description of
linear combinations of the operators O_{m_1 ... m_n} such that all m_i are
equal on average. This agreement provides a map between the operators in the
boundary and the position of the spikes in the bulk. We further suggest that
moving the spikes in other directions should describe operators with
derivatives other than D_+ indicating that these ideas are quite generic and
should help in unraveling the string description of the large-N limit of gauge
theories.Comment: 23 pages, 5 figures. v2: References and comments adde
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