41,628 research outputs found
Horizon Mass Theorem
A new theorem for black holes is found. It is called the horizon mass
theorem. The horizon mass is the mass which cannot escape from the horizon of a
black hole. For all black holes: neutral, charged or rotating, the horizon mass
is always twice the irreducible mass observed at infinity. Previous theorems on
black holes are: 1. the singularity theorem, 2. the area theorem, 3. the
uniqueness theorem, 4. the positive energy theorem. The horizon mass theorem is
possibly the last general theorem for classical black holes. It is crucial for
understanding Hawking radiation and for investigating processes occurring near
the horizon.Comment: A new theorem for black holes is establishe
Hybrid bounds for twisted L-functions
The aim of this paper is to derive bounds on the critical line Rs 1/2 for L- functions attached to twists f circle times chi of a primitive cusp form f of level N and a primitive character modulo q that break convexity simultaneously in the s and q aspects. If f has trivial nebentypus, it is shown that
L(f circle times chi, s) << (N vertical bar s vertical bar q)(epsilon) N-4/5(vertical bar s vertical bar q)(1/2-1/40),
where the implied constant depends only on epsilon > 0 and the archimedean parameter of f. To this end, two independent methods are employed to show
L(f circle times chi, s) << (N vertical bar s vertical bar q)(epsilon) N-1/2 vertical bar S vertical bar(1/2)q(3/8) and
L(g,s) << D-2/3 vertical bar S vertical bar(5/12)
for any primitive cusp form g of level D and arbitrary nebentypus (not necessarily a twist f circle times chi of level D vertical bar Nq(2))
Interference Effects Due to Commensurate Electron Trajectories and Topological Crossovers in (TMTSF)2ClO4
We report angle-dependent magnetoresistance measurements on (TMTSF)2ClO4 that
provide strong support for a new macroscopic quantum phenomenon, the
interference commensurate (IC) effect, in quasi-one dimensional metals. In
addition to observing rich magnetoresistance oscillations, and fitting them
with one-electron calculations, we observe a clear demarcation of
field-dependent behavior at local resistance minima and maxima (versus field
angle). Anticipated by a theoretical treatment of the IC effect in terms of
Bragg reflections in the extended Brillouin zone, this behavior results from
1D-2D topological crossovers of electron wave functions as a function of field
orientation.Comment: 14 page
Understanding/unravelling carotenoid excited singlet states.
Carotenoids are essential light-harvesting pigments in natural photosynthesis. They absorb in the blue–green region of the solar spectrum and transfer the absorbed energy to (bacterio-)chlorophylls, and thus expand the wavelength range of light that is able to drive photosynthesis. This process is an example of singlet–singlet excitation energy transfer, and carotenoids serve to enhance the overall efficiency of photosynthetic light reactions. The photochemistry and photophysics of carotenoids have often been interpreted by referring to those of simple polyene molecules that do not possess any functional groups. However, this may not always be wise because carotenoids usually have a number of functional groups that induce the variety of photochemical behaviours in them. These differences can also make the interpretation of the singlet excited states of carotenoids very complicated. In this article, we review the properties of the singlet excited states of carotenoids with the aim of producing as coherent a picture as possible of what is currently known and what needs to be learned
Multivariate adaptive regression splines models for vehicular emission prediction
© 2015, Oduro et al. Background: Rate models for predicting vehicular emissions of nitrogen oxides (NO X) are insensitive to the vehicle modes of operation, such as cruise, acceleration, deceleration and idle, because these models are usually based on the average trip speed. This study demonstrates the feasibility of using other variables such as vehicle speed, acceleration, load, power and ambient temperature to predict (NO X) emissions to ensure that the emission inventory is accurate and hence the air quality modelling and management plans are designed and implemented appropriately. Methods: We propose to use the non-parametric Boosting-Multivariate Adaptive Regression Splines (B-MARS) algorithm to improve the accuracy of the Multivariate Adaptive Regression Splines (MARS) modelling to effectively predict NO X emissions of vehicles in accordance with on-board measurements and the chassis dynamometer testing. The B-MARS methodology is then applied to the NO X emission estimation. Results: The model approach provides more reliable results of the estimation and offers better predictions of NO X emissions. Conclusion: The results therefore suggest that the B-MARS methodology is a useful and fairly accurate tool for predicting NO X emissions and it may be adopted by regulatory agencies
Casimir Dispersion Forces and Orientational Pairwise Additivity
A path integral formulation is used to study the fluctuation-induced
interactions between manifolds of arbitrary shape at large separations. It is
shown that the form of the interactions crucially depends on the choice of the
boundary condition. In particular, whether or not the Casimir interaction is
pairwise additive is shown to depend on whether the ``metallic'' boundary
condition corresponds to a ``grounded'' or an ``isolated'' manifold.Comment: 6 pages, RevTe
Dampak Pandemi Covid-19 Terhadap pendapatan Rumah Tangga Nelayan (Rtn) Di Pesisir Teluk Ambon
Pandemic Covid-19 yang melanda dunia mengakibatkan terkendalanya kegiatan ekonomi termasuk usaha dibidang perikanan tangkap. Kebijakan pemerintah terkait PSBB (Pembatasan Sosial Berskala Besar) dan protokol kesehatan yang mengharuskan menjaga jarak akibatpandemi Covid-19 mengakibatkan banyak usaha penangkapan ikan yang mengalami kerugian berupa turunnya ekspor komoditas perikanan dan terputusnya rantai pemasaran (Mardhia, 2020), serta terbatasnya operasi penangkapan ikan dan mobilitas distribusi hasiltangkapan ikan oleh nelayan. Hal yang sama juga terasa oleh rumah tangganelayan yang mendiami pesisir Teluk Ambon, baik dari segi persepsi terhadap pemberlakuan pembatasan operasi penangkapan ikan maupun dari segi pendapatan rumah tangga nelayan. Penelitian ini bertujuan untuk mengkaji dampak Pandemi Covid-19 terhadap pendapatan Rumah Tangga Nelayan dan persepsi nelayan di pesisir Teluk Ambon. Penelitian ini dilakukan selama 4bulan yakni pada bulan Februari- Mei 2021. Penelitian ini berlokasi di Pesisir Teluk Ambon, tepatnya di 3 (tiga) Desa pesisir yakniDesaRumah Tiga, DesaHativeBesar,dan Desa Laha. Metode pengumpulan data yangdigunakan dalam penelitian ini adalah metode observasi dan wawancara (Agung, 2012). Untuk mengetahui dampak pandemi Covid19 terhadap pendapatan rumahtangga nelayan dan persepsi nelayan dianalisis menggunakan metode deskriptif (Hidayat, 2012; Sugiyono, 2018). Hasil penelitian menunjukkan bahwa faktor- factor yang penyebab perubahan pendapatan rumah tangga nelayan pada saat pandemi Covid-19 di Kecamatan Teluk Ambon adalah adanya pengurangan frekuensi melaut, penurunan harga hasil tangkapan dan berubahnya distribusi hasil tangkapan dimana hasil perbandingan pendapatan rumah tangga nelayan sebelum dan pada saat pandemic covid-19 menunjukkan bahwa pendapatan rumah tangga nelayan mengalami penurunan pada saat pandemi covid-19 dibandingkan dengan pada saat sebelum pandemi covid19, masing-masing pada nelayan mini purse seine sebesar32%, pada nelayan pancing tonda sebesar 37%, pada delayan pancing ulur sebesar 23%, dan nelayan jaring insang sebesar 21%
Diffusion-limited loop formation of semiflexible polymers: Kramers theory and the intertwined time scales of chain relaxation and closing
We show that Kramers rate theory gives a straightforward, accurate estimate
of the closing time of a semiflexible polymer that is valid in cases
of physical interest. The calculation also reveals how the time scales of chain
relaxation and closing are intertwined, illuminating an apparent conflict
between two ways of calculating in the flexible limit.Comment: Europhys. Lett., 2003 (in press). 8 pages, 3 figures. See also,
physics/0101087 for physicist's approach to and the importance of
semiflexible polymer looping, in DNA replicatio
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