1,241 research outputs found
Cooking with Roots: How Older Adults Strengthen Connection with Younger Generations Through Recipe Sharing
This research investigates how older adults experience sharing recipes with younger generations, and examines conditions that contribute to the expression of generativity within the context of intergenerational recipe sharing. In Study 1, semi-structured interviews centered on experiences with intergenerational recipe sharing will be conducted with 30 older adults (age 65+). Participants will complete a survey of generative concern before and after engaging in a basic recipe sharing task. In line with previous research on generative art activities, responses will highlight feelings of autonomy as well as desires to teach others and leave a legacy. It is also hypothesized that generative concern will increase as a consequence of the recipe sharing task. Following preliminary research, Study 2 will examine how recipe type (special occasion vs. everyday-style recipe), mode of sharing (oral vs. written), and identity of recipe recipient (relative vs. stranger) influence generative concern in 792 older adults. Participants will complete the same survey described in Study 1 before being randomly assigned to one of eight recipe sharing tasks. After three sharing sessions, participants will be re-tested for present and future-oriented generativity. While all groups will show an increase in generativity over time, participants who share recipes with a younger relative and those who share recipes orally will benefit more from the intervention than their counterparts. Results will suggest that generativity is dependent on factors of recipe type, mode of sharing, and recipe recipient when recipes are passed from one generation to another. Implications and further directions are discussed, including intergenerational learning, well-being, and ego integrity in late life
Intermediate inflation and the slow-roll approximation
It is shown that spatially homogeneous solutions of the Einstein equations
coupled to a nonlinear scalar field and other matter exhibit accelerated
expansion at late times for a wide variety of potentials . These potentials
are strictly positive but tend to zero at infinity. They satisfy restrictions
on and related to the slow-roll approximation. These results
generalize Wald's theorem for spacetimes with positive cosmological constant to
those with accelerated expansion driven by potentials belonging to a large
class.Comment: 19 pages, results unchanged, additional backgroun
Cosmology with positive and negative exponential potentials
We present a phase-plane analysis of cosmologies containing a scalar field
with an exponential potential
where and may be positive or negative. We show that
power-law kinetic-potential scaling solutions only exist for sufficiently flat
() negative
potentials. The latter correspond to a class of ever-expanding cosmologies with
negative potential. However we show that these expanding solutions with a
negative potential are to unstable in the presence of ordinary matter, spatial
curvature or anisotropic shear, and generic solutions always recollapse to a
singularity. Power-law kinetic-potential scaling solutions are the late-time
attractor in a collapsing universe for steep negative potentials (the ekpyrotic
scenario) and stable against matter, curvature or shear perturbations.
Otherwise kinetic-dominated solutions are the attractor during collapse (the
pre big bang scenario) and are only marginally stable with respect to
anisotropic shear.Comment: 8 pages, latex with revtex, 9 figure
Closed cosmologies with a perfect fluid and a scalar field
Closed, spatially homogeneous cosmological models with a perfect fluid and a
scalar field with exponential potential are investigated, using dynamical
systems methods. First, we consider the closed Friedmann-Robertson-Walker
models, discussing the global dynamics in detail. Next, we investigate
Kantowski-Sachs models, for which the future and past attractors are
determined. The global asymptotic behaviour of both the
Friedmann-Robertson-Walker and the Kantowski-Sachs models is that they either
expand from an initial singularity, reach a maximum expansion and thereafter
recollapse to a final singularity (for all values of the potential parameter
kappa), or else they expand forever towards a flat power-law inflationary
solution (when kappa^2<2). As an illustration of the intermediate dynamical
behaviour of the Kantowski-Sachs models, we examine the cases of no barotropic
fluid, and of a massless scalar field in detail. We also briefly discuss
Bianchi type IX models.Comment: 15 pages, 10 figure
Accelerated cosmological expansion due to a scalar field whose potential has a positive lower bound
In many cases a nonlinear scalar field with potential can lead to
accelerated expansion in cosmological models. This paper contains mathematical
results on this subject for homogeneous spacetimes. It is shown that, under the
assumption that has a strictly positive minimum, Wald's theorem on
spacetimes with positive cosmological constant can be generalized to a wide
class of potentials. In some cases detailed information on late-time
asymptotics is obtained. Results on the behaviour in the past time direction
are also presented.Comment: 16 page
Scaling Solutions in Robertson-Walker Spacetimes
We investigate the stability of cosmological scaling solutions describing a
barotropic fluid with and a non-interacting scalar field
with an exponential potential V(\phi)=V_0\e^{-\kappa\phi}. We study
homogeneous and isotropic spacetimes with non-zero spatial curvature and find
three possible asymptotic future attractors in an ever-expanding universe. One
is the zero-curvature power-law inflation solution where
(). Another is the
zero-curvature scaling solution, first identified by Wetterich, where the
energy density of the scalar field is proportional to that of matter with
(). We find that
this matter scaling solution is unstable to curvature perturbations for
. The third possible future asymptotic attractor is a solution with
negative spatial curvature where the scalar field energy density remains
proportional to the curvature with
(). We find that solutions with are
never late-time attractors.Comment: 8 pages, no figures, latex with revte
Anisotropic Power-law Inflation
We study an inflationary scenario in supergravity model with a gauge kinetic
function. We find exact anisotropic power-law inflationary solutions when both
the potential function for an inflaton and the gauge kinetic function are
exponential type. The dynamical system analysis tells us that the anisotropic
power-law inflation is an attractor for a large parameter region.Comment: 14 pages, 1 figure. References added, minor corrections include
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