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131.
We study the probability for a random line to intersect a given plane curve, over a finite field, in a given number of points over the same field. In particular, we focus on the limits of these probabilities under successive finite field extensions. Supposing absolute irreducibility for the curve, we show how a variant of the Chebotarev density theorem for function fields can be used to prove the existence of these limits, and to compute them under a mildly stronger condition, known as simple tangency. Partial results have already appeared in the literature, and we propose this work as an introduction to the use of the Chebotarev theorem in the context of incidence geometry. Finally, Veronese maps allow us to compute similar probabilities of intersection between a given curve and random curves of given degree. 相似文献
132.
Spherically symmetric static cosmological models filled with black-body radiation are considered. The models are isotropic
about a central observer but inhomogeneous. It is suggested that the energy density of the free gravitational field, which
is coupled to the isotropic radiation energy density, might play an important role in generating sufficient field (vacuum)
energy (when converted into thermal energy) and initiate processes like inflation. On the central world line the energy density
of the free gravitational field vanishes whereas the proper pressure and density of the isotropic black-body radiation are
constants. Further, it is shown that the cosmological constant is no more arbitrary but given in terms of the central pressure
and density. Also, at its maximum value the energy density of the free gravitational field is proved to be equal to one third
of the combined value of radiation pressure and density. 相似文献
133.
Summary In this paper we have estimated the sensitivity of a large-mass liquid-scintillation detector to search for supernova neutrinos
of different flavours. Events produced by νμ and ντ interactions can be identified by looking at the distorsion in the neutrino energy spectrum. We have shown here that, overlapped
to the main energy distribution produced by
interactions with protons a peak at 15.11 MeV (due to the de-excitation of12C* nuclei excited by neutral-current neutrino interactions) gives a possible signature of these neutrino flavours.
Due to the relevance of its scientific content, this paper has been given priority by the Journal Direction. 相似文献
134.
本文提出了一种测试激光拉曼分光计中超低杂散光的新方法.实验结果表明,本方法的杂散光测量限可达10~(-14)量级. 相似文献
135.
用1m法向入射光谱仪观察三电极真空火花发射的Ti五次离化光谱。在24~200nm波段内观察到157条TiVI的新谱线。根据新归属的TiVI谱线定出11个新能级,并对5个有疑问的能级值作了修正。 相似文献
136.
J. Sunklodas 《Lithuanian Mathematical Journal》2007,47(3):327-335
We estimate the difference
for bounded functions h: ℝ → ℝ satisfying the Lipschitz condition, where Z
v
= B
v
−1
∑
i=0
∞
v
i
X
i
and
with discount factor ν such that 0 < ν < 1. Here {X
n
, n ≥ 0} is a sequence of strongly mixing random variables with
, and N is a standard normal random variable. In a particular case, the obtained upper bounds are of order O((1 − ν)1/2).
Published in Lietuvos Matematikos Rinkinys, Vol. 47, No. 3, pp. 399–409, July–September, 2007.
The research was partially supported by the Lithuanian State Science and Studies Foundation, grant No. T-15/07. 相似文献
137.
Yu. A. Volkov 《Theoretical and Mathematical Physics》2007,151(1):556-565
We show that the method of “finite-size” particles is a discrete model of the Vlasov equation but in a different (effective)
interaction potential. We calculate the effective potential explicitly in the most interesting case of the Coulomb interaction.
We find the equations of motion of particles of “finite size” for the Gaussian form factor.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 151, No. 1, pp. 138–148, April, 2007. 相似文献
138.
139.
Steven Weinstein 《Foundations of Physics》2009,39(8):921-936
Bell’s theorem is purported to demonstrate the impossibility of a local “hidden variable” theory underpinning quantum mechanics.
It relies on the well-known assumption of ‘locality’, and also on a little-examined assumption called ‘statistical independence’
(SI). Violations of this assumption have variously been thought to suggest “backward causation”, a “conspiracy” on the part of
nature, or the denial of “free will”. It will be shown here that these are spurious worries, and that denial of SI simply implies nonlocal correlation between spacelike degrees of freedom. Lorentz-invariant theories in which SI does not hold are easily constructed: two are exhibited here. It is conjectured, on this basis, that quantum-mechanical phenomena
may be modeled by a local theory after all.
This paper is dedicated to the memory of John A. Wheeler. 相似文献
140.
Jun Ren 《International Journal of Theoretical Physics》2009,48(7):2088-2097
In this paper, we study the thermal properties of the inner horizon of a Kerr-Newman black hole. By adopting Damour-Ruffini
method and the thin film model which is developed on the base of brick wall model suggested by ’t Hooft, we calculate the
temperature and the entropy of the inner horizon of a Kerr-Newman black hole. We conclude that the temperature of inner horizon
is positive and the entropy of the inner horizon is proportional to the area of the inner horizon. The cut-off factor is same
as it in calculation of the entropy of the outer horizon, 90β. In addition, we write the integral and differential Bekenstein-Smarr formula as the parameters of the inner horizon. Then,
we discuss that if the contribution of the inner horizon is taken into account to the total entropy of the black hole, the
Nernst theorem can be satisfied. At last, We calculate the tunneling rate of the outer horizon Γ+ and the inner horizon Γ−. The total tunneling rate Γ should be the product of the rates of the outer and inner horizon, Γ=Γ+⋅Γ−. We find that the total tunneling rate is in agreement with the Parikh’s standard result, Γ→exp (ΔS
BH
), and there is no information loss. 相似文献