767 research outputs found
SÄáčkhya-Yoga Philosophy and the Mind-Body Problem
The relationship between the physical body and the conscious human mind has been a deeply problematic topic for centuries. Physicalism is the 'orthodox' metaphysical stance in contemporary Western thought, according to which reality is exclusively physical/material in nature. However, in the West, theoretical dissatisfaction with this type of approach has historically lead to Cartesian-style dualism, wherein mind and body are thought to belong to distinct metaphysical realms. In the current discussion I compare and contrast this standard Western approach with an alternative form of dualism developed in the SÄáčkhya-Yoga philosophical tradition, where matter and pure consciousness are held to belong to distinct and independent realms, but where the mind is placed on the material side of the ontological divide. I argue that this model possesses a number of theoretical advantages over Cartesian-style dualism, and constitutes a compelling theoretical framework for re-conceptualizing the mind-body problem
Advaita and the philosophy of consciousness without an object
The paper explores Ćaáč
kara's position on autonomous consciousness, or cit, as the fundamental reality. As such, cit transcends subject/object duality, and Ćaáč
kara holds that consciousness is ultimately nirviáčŁayaka or non-intentional. I compare and contrast the Advaita view with the contemporary Phenomenological account, wherein consciousness is held to be essentially intentional, so that consciousness is always of or about some object or content, and where consciousness without an object is deemed conceptually impossible
Globular Cluster Populations in Four Early-Type Poststarburst Galaxies
We present a study of the globular cluster systems of four early-type
poststarburst galaxies using deep g and I-band images from the ACS camera
aboard the Hubble Space Telescope (HST). All the galaxies feature shells
distributed around their main bodies and are thus likely merger remnants. The
color distribution of the globular clusters in all four galaxies shows a broad
peak centered on g-I ~ 1.4, while PGC 6240 and PGC 42871 show a significant
number of globular clusters with g-I ~ 1.0. The latter globular clusters are
interpreted as being of age ~ 500 Myr and likely having been formed in the
merger. The color of the redder peak is consistent with that expected for an
old metal-poor population that is very commonly found around normal galaxies.
However, all galaxies except PGC 10922 contain several globular clusters that
are significantly brighter than the maximum luminosity expected of a single old
metal-poor population. To test for multiple-age populations of overlapping g-I
color, we model the luminosity functions of the globular clusters as composites
of an old metal-poor subpopulation with a range of plausible specific
frequencies and an intermediate-age subpopulation of solar metallicity. We find
that three of the four sample galaxies show evidence for the presence of an
intermediate-age (~ 1 Gyr) globular cluster population, in addition to the old
metal-poor GC population seen in normal early-type galaxies. None of the
galaxies show a significant population of clusters consistent with an old,
metal-rich red cluster population that is typically seen in early-type
galaxies.Comment: 41 pages, 13 figures, accepted for publication in AJ. Some figues
have been downgraded to reduce their size
The fluorine-NHC gauche effect: a structural and computational study
Herein, we report the synthesis and X-ray structural analysis of a collection of fluorinated metal
N-heterocyclic carbenes (Ag, Au, Pd, Rh, Ir) and their precursor salts. The common structural
feature of these species is a flanking fluoroethyl group which is either freely rotating or
embedded within a bicyclic framework. Solid state analysis confirmed a gauche conformational
preference in all cases with the fluorine adopting a syn clinal arrangement (Ï[NCCF] ~ 60°) with
respect to the triazolium nitrogen at the vicinal position of the NHC. A density functional theory
analysis was employed to quantify these effects and evaluate the influence of electronic
modulation of the carbenic carbon [(C=N+); neutral carbene (C:); metal-bound carbene (C=M)],
on the relative gauche / anti preference, thus highlighting the potential of this conformational
phenomenon as a useful molecular design strategy for controlling the topology of organometallic
complexes
Deep Luminosity Functions of Old and Intermediate-Age Globular Clusters in NGC 1316: Evidence for Dynamical Evolution of Second-Generation Globular Clusters
The Advanced Camera for Surveys on board the Hubble Space Telescope has been
used to obtain deep high-resolution images of the giant early-type galaxy NGC
1316 which is an obvious merger remnant. These observations supersede previous,
shallower observations which revealed the presence of a population of
metal-rich globular clusters of intermediate age (~ 3 Gyr). We detect a total
of 1496 cluster candidates, almost 4 times as many as from the previous WFPC2
images. We confirm the bimodality of the color distribution of clusters, even
in V-I, with peak colors 0.93 and 1.06. The large number of detected clusters
allows us to evaluate the globular cluster luminosity functions as a function
of galactocentric radius. We find that the luminosity function of the inner 50%
of the intermediate-age, metal-rich (`red') population of clusters differs
markedly from that of the outer 50%. In particular, the luminosity function of
the inner 50% of the red clusters shows a clear flattening consistent with a
turnover that is about 1.0 mag fainter than the turnover of the blue clusters.
This constitutes the first direct evidence that metal-rich cluster populations
formed during major mergers of gas-rich galaxies can evolve dynamically
(through disruption processes) into the red, metal-rich cluster populations
that are ubiquitous in `normal' giant ellipticals.Comment: Accepted for publication in ApJ Letters; 4 pages in emulateapj style.
3 figure
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