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1.
本文对三个不动中心问题的平面解作进一步发展,通过对三个不动中心在四维空间中的定义得到三个不动中心问题的三维解. 相似文献
2.
光引力限制性三体问题的平动点 总被引:2,自引:1,他引:1
本文研究两个主星体的质量缩减因子q_,q_2∈(-∞,1]的光引力限制性三体问题。文中给出一种平动点的个数估计和位置计算的分析方法。结果表明对于不同的q_1和q_2可有1~7个平动点。作为应用,文末还讨论了太阳系类似彗尾尘埃物质的运动。 相似文献
3.
ATHREE-DIMENSIONALSOLUTIONOFTHEPROBLEMOFTHREEFIXEDCENTRES¥QinYiping(覃一平)NieZhaoming(聂昭明)(YunnanObservatory,AcademiaSinica,Kun... 相似文献
4.
THELIBRATIONPOINTSINPHOTOGRAVITATIONALRESTRICTEDTHREE-BODYPROBLEMZhengXue-tang(郑学塘)YuLi-zhong(郁丽忠)(Dept.ofAppliedPhysics,Nanj... 相似文献
5.
Supplement to the previous application of the first junction condition to a highly symmetric spacetime
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Application of the first junction condition to a highly symmetric
spacetime was investigated recently in {\it Chin. Phys. Lett.} B {\bf
546} 189 2006, where a partial differential equation arising from the
connection of the Robertson--Walker and the Schwarzschild--de Sitter
metrics was presented, but no solutions of the equation were
provided. Here we provide a proof to the statement that there exist
solutions of the equation. In addition, an example of the solution
and some analyses associated with this issue are presented. We find
that in connecting the two metrics, there are three conditions which
should be satisfied. Of these conditions, one condition constrains
the place where the two metrics can take the same value for a local
system whose mass is provided which marks the boundary of the system,
and the other two constrain the transformation form. In realizing the
connection of the two metrics, the latter two conditions are required
to be satisfied only at the boundary defined by the former condition. 相似文献
6.
According to recent investigations of states of quantum fields, we
postulate that there exist negative energy photons in the universe.
With this assumption, we find a solution of Einstein's equation
without introducing the cosmological constant. A new and sizable
type Ia supernovae sample is employed to perform a fit with our
model and the conventional model. Both models can well account for
the current type Ia supernovae observation and they are not
distinguishable. With the new model, the cause of the accelerated
expansion of the universe and the mechanism of the negative pressure
existing in outer space can be explained in ordinary physical terms. 相似文献
7.
Applications of the Junction Conditions Connecting the Robertson-Walker Metric and the Metric of a Local System on Our Universe
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We investigate how the local and global metrics are connected in an ideal model of spacetime where the local system is assumed to be highly symmetric and the cosmological matter is kept away from the local system and does not disturbed by the local system. A boundary condition arising from the junction conditions is obtained and its implication in our universe is studied. We know that the total mass of a sufficiently large system must be that of the cosmological matter within the region of that size. This requirement is satisfied since it is just a consequence of the boundary condition. The analysis shows that at the very late epoch of the universe, there exists a particular time when the largest symmetric local systems stop growing and the observation of this time can be used to check the cosmological parameters. Adopting the popular values (ΩM, Ωa) = (0.28, 0.72), we find that particular time would be associated with z = 0.726, the effect of dark matter on the clustering of objects would be insignificant, and the Virgo cluster would be gravitationally bound even if dark matter is ignored. 相似文献
8.
Development of the spectrum of gamma-ray burst pulses influenced by the intrinsic spectral evolution and the curvature effect
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The spectral evolution of gamma-ray burst pulses assumed to arise from
the emission of fireballs is explored. It is found that due to the
curvature effect, the integrated flux is well related to peak energy
by a power law in the decaying phase of pulses, where the index is
about 3, which does not depend on intrinsic emission and the Lorentz
factor. The spectra of pulses in the decaying phase are slightly
different from each other when different intrinsic spectral
evolution patterns are considered, indicating that it is dominated
by the curvature effect. In the rising phase, the integrated flux
keeps increasing whilst the peak energy remains unchanged when the
intrinsic emission bears an unchanged spectrum. Within this phase,
the flux decreases with the increase of the peak energy for a
hard-to-soft intrinsic spectrum, and for a soft-to-hard-to-soft
intrinsic spectrum, the flux generally increases with the increase
of the peak energy. An intrinsic soft-to-hard-to-soft spectral
evolution within a co-moving pulse would give rise to a pulse-like
evolutionary curve for the peak energy. 相似文献
9.
Origination of gamma-ray burst pulses associated with the Doppler effect of spherical fireballs or uniform jet
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Ryde and Petrosian have pointed out that the rise phases of
gamma-ray burst (GRB) pulses originate from the widths of the
intrinsic pulses and their decay phases are determined by the
curvature effect of the expanding fireball surface based on their
simplified formula. In this paper we investigate in detail the issue
based on the formula in Ref.[20], which is derived based on a model
of highly symmetric expanding fireballs, where the Doppler effect is
the key factor to be concerned about, and no terms are omitted in
their derivation. Our analyses show that the decay phases of the
observed pulses originate from the contributions from both the
curvature effect of the expanding fireball and the two timescales of
the local pulses, and the rise phases of the observed pulses only
come from the two timescales of the local pulses. Associated with a
local pulse with both rise and decay portions, the light curve of
GRBs in the rise portion is expected to undergo a concave phase and
then a convex one, whereas that in the decay portion is expected to
evolve by an opposite process. And the ratio of the concave timescale
to the convex one in the rise phase of the observed pulse linearly
increases with the ratio of the rising timescale to the decay one of
the local pulse ($r_{\rm rd}$), whereas the ratio of the convex
timescale to the concave timescale in its decay phase linearly
decreases with $r_{\rm rd}$. The two correlations are independent of
the local pulse forms and the rest-frame radiation forms. But the
different forms of local pulses and the different values of $r_{\rm
rd}$ gives rise to the diversity of the light curve pulse shapes. We
test a sample of 86 GRB pulses detected by the BATSE instrument on
board the Compton Gamma Ray Observatory and find that the
characteristics do exist in the light curve of GRBs. 相似文献
10.
Method of determining cosmological parameter ranges with samples of candles with an intrinsic distribution
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In this paper, the effect of the intrinsic distribution of cosmological candles is
investigated. We find that in the case of a narrow distribution the deviation of the
observed modulus of sources from the expected central value can be estimated within
a ceratin range. We thus introduce lower and upper limits of X2, X
min2 and Xmax2 to estimate cosmological parameters by
applying the conventional minimizing X2 method. We apply this method to a
gamma-ray burst (GRB) sample as well as to a combined sample including this GRB
sample and an SN Ia sample. Our analysis shows that: a) in the case of assuming an
intrinsic distribution of candles of the GRB sample, the effect of the distribution
is obvious and should not be neglected; b) taking into account this effect would
lead to a poorer constraint of the cosmological parameter ranges. The analysis
suggests that in the attempt of constraining the cosmological model with current GRB
samples, the results tend to be worse than was previously anticipated if the
mentioned intrinsic distribution does exist. 相似文献