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1.
Recent observations on Type-Ia supernovae and low density (Ω
m
=0.3) measurement of matter including dark matter suggest that the present-day universe consists mainly of repulsive-gravity
type ‘exotic matter’ with negative-pressure often said ‘dark energy’ (Ω
x
=0.7). But the nature of dark energy is mysterious and its puzzling questions, such as why, how, where and when about the
dark energy, are intriguing. In the present paper the authors attempt to answer these questions while making an effort to
reveal the genesis of dark energy and suggest that ‘the cosmological nuclear binding energy liberated during primordial nucleo-synthesis
remains trapped for a long time and then is released free which manifests itself as dark energy in the universe’. It is also
explained why for dark energy the parameter
w=-\frac23w=-\frac{2}{3}
. Noting that w=1 for stiff matter and
w=\frac13w=\frac{1}{3}
for radiation;
w=-\frac23w=-\frac{2}{3}
is for dark energy because “−1” is due to ‘deficiency of stiff-nuclear-matter’ and that this binding energy is ultimately
released as ‘radiation’ contributing “
+\frac13+\frac{1}{3}
”, making
w=-1+\frac13=-\frac23w=-1+\frac{1}{3}=-\frac{2}{3}
. When dark energy is released free at Z=80,
w=-\frac23w=-\frac{2}{3}
. But as on present day at Z=0 when the radiation-strength-fraction (δ), has diminished to δ→0, the
w=-1+d\frac13=-1w=-1+\delta\frac{1}{3}=-1
. This, almost solves the dark-energy mystery of negative pressure and repulsive-gravity. The proposed theory makes several
estimates/predictions which agree reasonably well with the astrophysical constraints and observations. Though there are many
candidate-theories, the proposed model of this paper presents an entirely new approach (cosmological nuclear energy) as a
possible candidate for dark energy. 相似文献
2.
In this paper, we consider the global wellposedness of the 3-D incompressible anisotropic Navier-Stokes equations with initial
data in the critical Besov-Sobolev type spaces B{\mathcal{B}} and
B-\frac12,\frac124{\mathcal{B}^{-\frac12,\frac12}_4} (see Definitions 1.1 and 1.2 below). In particular, we proved that there exists a positive constant C such that (ANS
ν
) has a unique global solution with initial data u0 = (u0h, u03){u_0 = (u_0^h, u_0^3)} which satisfies
||u0h||B exp(\fracCn4 ||u03||B4) £ c0n{\|u_0^h\|_{\mathcal{B}} \exp\bigl(\frac{C}{\nu^4} \|u_0^3\|_{\mathcal{B}}^4\bigr) \leq c_0\nu} or
||u0h||B-\frac12,\frac124 exp(\fracCn4 ||u03||B-\frac12,\frac1244) £ c0n{\|u_0^h\|_{\mathcal{B}^{-\frac12,\frac12}_{4}} \exp \bigl(\frac{C}{\nu^4} \|u_0^3\|_{\mathcal{B}^{-\frac12,\frac12}_{4}}^4\bigr)\leq c_0\nu} for some c
0 sufficiently small. To overcome the difficulty that Gronwall’s inequality can not be applied in the framework of Chemin-Lerner
type spaces, [(Lpt)\tilde](B){\widetilde{L^p_t}(\mathcal{B})}, we introduced here sort of weighted Chemin-Lerner type spaces, [(L2t, f)\tilde](B){\widetilde{L^2_{t, f}}(\mathcal{B})} for some apropriate L
1 function f(t). 相似文献
3.
F. Rahaman Peter K. F. Kuhfittig K. Chakraborty M. Kalam D. Hossain 《International Journal of Theoretical Physics》2011,50(9):2655-2665
This paper discusses a new model for galactic dark matter by combining an anisotropic pressure field corresponding to normal
matter and a quintessence dark energy field having a characteristic parameter ω
q
such that
-1 < wq < -\frac13-1<\omega_{q}< -\frac{1}{3}. Stable stellar orbits together with an attractive gravity exist only if ω
q
is extremely close to
-\frac13-\frac{1}{3}, a result consistent with the special case studied by Guzman et al. (Rev. Mex. Fis. 49:303, 2003). Less exceptional forms of quintessence dark energy do not yield the desired stable orbits and are therefore unsuitable
for modeling dark matter. 相似文献
4.
This paper considers Hardy–Lieb–Thirring inequalities for higher order differential operators. A result for general fourth-order
operators on the half-line is developed, and the trace inequality
tr( (-D)2 - CHRd,2\frac1|x|4 - V(x) )-g £ Cgò\mathbbRd V(x)+g+ \fracd4 dx, g 3 1 - \frac d 4,\mathrm{tr}\left( (-\Delta)^2 - C^{\mathrm{HR}}_{d,2}\frac{1}{|x|^4} - V(x) \right)_-^{\gamma}\leq C_\gamma\int\limits_{\mathbb{R}^d} V(x)_+^{\gamma + \frac{d}{4}}\,\mathrm{d}x, \quad \gamma \geq 1 - \frac d 4, 相似文献
5.
In appropriate units, the Brown-Ravenhall Hamiltonian for a system of 1 electron relativistic molecules with K fixed nuclei having charge and position Zk, Rk, k=1,2, ?,Kk=1,2, \ldots,K, is of the form \bB1,K = L+ ( D0 + aVc) L+ \bB_{1,K}= \Lambda_+ \bigl( D_0 + \alpha V_c\bigr) \Lambda_+ , where v+ is the projection onto the positive spectral subspace of the free Dirac operator D0 and Vc = - ?k=1K \fracaZk\lmod \bx-Rk \rmod + ?k < l, k,l=1K \fracaZk Zl\lmod Rk-Rl \rmod V_c= - \sum_{k=1}^K \frac{\alpha Z_k}{\lmod \bx-R_k \rmod} + \sum_{k
6.
By introducing the mixing of scalar mesons in the chiral SU(3) quark model, we dynamically investigate the baryon-baryon interaction. The hyperon-nucleon and nucleon-nucleon interactions
are studied by solving the resonating group method (RGM) equation in a coupled-channel calculation. In our present work, the
experimental lightest pseudoscalar p \pi, K,h \eta,h¢ \eta^{{\prime}}_{} mesons correspond exactly to the chiral nonet pseudoscalar fields p \pi, K,h \eta,h¢ \eta^{{\prime}}_{} in the chiral SU(3) quark model. The h \eta,h¢ \eta^{{\prime}}_{} mesons are considered as the mixing of singlet and octet mesons, and the mixing angle qps \theta_{{ps}}^{} is taken to be -23° . For scalar nonet mesons, we suppose that there exists a correspondence between the experimental lightest scalar f
0(600) , k \kappa , a
0(980) , f
0(980) mesons and the theoretical scalar nonet s \sigma , k \kappa , s¢ \sigma^{{\prime}}_{} , e \epsilon fields in the chiral SU(3) quark model. For scalar mesons, we consider two different mixing cases: one is the ideal mixing and another is the qs \theta_{s}^{} = 19° mixing. The masses of the s¢ \sigma^{{\prime}}_{} and e \epsilon mesons are taken to be 980MeV, which are just the masses of the experimental a
0(980) , f
0(980) mesons. The mass of the s \sigma meson is an adjustable parameter and is decided by fitting the binding energy of the deuteron, the masses of 560MeV and 644MeV
are obtained for the ideal mixing and the qs \theta_{s}^{} = 19° mixing, respectively. We find that, in order to reasonably describe the YN interactions, the mass of the k \kappa meson is near 780MeV for the ideal mixing. However, we must enhance the mass of the k \kappa meson for the qs \theta_{s}^{} = 19° mixing, the 1050MeV is favorably used in the present work. The experimental s \sigma and k \kappa scalar mesons are very strange, both have larger widths. Hence, no matter what kind of mixing is considered, all the masses
of scalar mesons we used in the present work seem to be consistent with the present PDG information. 相似文献
7.
C. S. Fischer T. Goecke R. Williams 《The European Physical Journal A - Hadrons and Nuclei》2011,47(2):28
Using the Dyson-Schwinger and Bethe-Salpeter equations, we calculate the hadronic light-by-light scattering contribution to
the anomalous magnetic moment of the muon am\ensuremath a_\mu , using a phenomenological model for the gluon and quark-gluon interaction. We find am=(84 ±13)×10-11\ensuremath a_\mu=(84 \pm 13)\times 10^{-11} for meson exchange, and am = (107 ±2 ±46)×10-11\ensuremath a_\mu = (107 \pm 2 \pm 46)\times 10^{-11} for the quark loop. The former is commensurate with past calculations; the latter much larger due to dressing effects. This
leads to a revised estimate of am=116 591 865.0(96.6)×10-11\ensuremath a_\mu=116 591 865.0(96.6)\times 10^{-11} , reducing the difference between theory and experiment to ≃ 1.9s \sigma . 相似文献
8.
G. S. Khadekar Rupali Wanjari Cenap Ozel 《International Journal of Theoretical Physics》2009,48(9):2550-2557
In this study we have analyzed the Kaluza-Klein type Robertson Walker (RW) cosmological model by considering variable cosmological
constant term Λ of the form:
,
and Λ∼ρ in the presence of strange quark matter with domain wall. The various physical aspects of the model are also discussed. 相似文献
9.
Gustav Holzegel 《Communications in Mathematical Physics》2010,294(1):169-197
The massive wave equation ${\square_{g}\psi - \alpha \frac{\Lambda}{3}\psi = 0}
10.
Alejandro Cabo Montes de Oca 《The European Physical Journal C - Particles and Fields》2011,71(4):1620
A previous study of the dynamical generation of masses in massless QCD is considered from another viewpoint. The quark mass
is assumed to have a dynamical origin and is substituted for by a scalar field without self-interaction. The potential for
the new field background is evaluated up to two loops. Expressing the running coupling in terms of the scale parameter μ, the potential minimum is chosen to fix m
top=175 GeV when μ
0=498 MeV. The second derivative of the potential predicts a scalar field mass of 126.76 GeV. This number is close to the value
114 GeV, which preliminary data taken at CERN suggested to be associated with the Higgs particle. However, the simplifying
assumptions limit the validity of the calculations done, as indicated by the large value of
a = \frac g24p=1.077 \alpha=\frac {g^{2}}{4\pi}=1.077 obtained. However, supporting statements about the possibility of improving the scheme come from the necessary inclusion
of weak and scalar field couplings and mass counterterms in the renormalization procedure, in common with the seemingly needed
consideration of the massive W and Z fields, if the real conditions of the SM model are intended to be approached. 相似文献
11.
The capture cross section of a trapping or recombination center for a charge carrier has been defined as the quotient of the
capture coefficient and the average thermal velocity of the carrier distribution. For a Maxwellian distribution in a semiconductor
band with an ellipsoidal effective mass tensor, this average velocity can be expressed as
|