排序方式: 共有27条查询结果,搜索用时 15 毫秒
1.
2.
当SO(10)GUT(大统一理论)模型,通过两类45维伴随表示和16维旋量表示的Higgs场破缺,计算C-W型单圈有效势,获得了SO(10)GUT的暴涨宇宙模型,得出若宇宙暴涨产生时温度为T~10~(13)GeV,就能满足密度涨落(?)~10~(-4)要求,宇宙常数为1.38×10~(52)cm~(-2),宇宙在暴涨期尺度增大~10~(800)倍。 相似文献
3.
4.
5.
宇宙中物质的压力对宇宙年龄的影响 总被引:1,自引:0,他引:1
在标准宇宙学模型中,非相对论性物质(以下简称为物质)被视为无压的尘埃粒子[1],然而其合理性并未定量地证实过.Peebles[2]也曾提到过考虑宇宙中物质压力的必要性.目前的研究表明,在冷暗物质宇宙学模型基础上,宇宙中大尺度结构形成的高精度计算机数值模拟和理论分析都预言,在星系和星系团的中心应该有一个致密的核;然而这与目前的观测如星系团的引力透镜观测等相矛盾.最近Spergel等[3]假定冷暗物质之间存在着相互作用力,即存在着热压力,并对其做了深入研究,但也并未涉及其对宇宙年龄的影响. 相似文献
6.
本文提出也多层模糊控制器的,概念,揭示了模糊集合对于论域的相对性,采用偏差e和偏差变化c为输入.控制量u为输出的简单间模糊控制器的主要缺点是不能同时兼承系统的动静态性能。这主要是因为对连续论域的等问隔量化(离散化)和有限的量化等级。多层模糊控制器能灵活地处理论域和量化问题。从而可以克服简单模糊控制器的缺点、仿真结果表明多层模糊控制器具有比简单模糊控制器优越的性能。 相似文献
7.
关于电子产品定价的模糊综合评判 总被引:3,自引:0,他引:3
本文利用模糊数学的理论对电子产品的价值进行了综合评判,因而对其电子产品的质量,影响产品价值的因素有一个量的认识。 相似文献
8.
9.
Maria Rosa Antognazza 《Studies in history and philosophy of science》2003,34(2):309-327
This paper employs the revised conception of Leibniz emerging from recent research to reassess critically the ‘radical spiritual revolution’ which, according to Alexandre Koyré’s landmark book, From the closed world to the infinite universe (1957) was precipitated in the seventeenth century by the revolutions in physics, astronomy, and cosmology. While conceding that the cosmological revolution necessitated a reassessment of the place of value-concepts within cosmology, it argues that this reassessment did not entail a spiritual revolution of the kind assumed by Koyré, in which ‘value-concepts, such as perfection, harmony, meaning and aim’ were shed from the conception of the structure of the universe altogether. On the contrary, thanks to his pioneering intuition of the distinction between physical and metaphysical levels of explanation, Leibniz saw with great clarity that a scientific explanation of the universe which rejected the ‘closed world’ typical of Aristotelian cosmology did not necessarily require the abandonment of key metaphysical doctrines underlying the Aristotelian conception of the universe. Indeed the canon of value-concepts mentioned by Koyré—meaning, aim, perfection and harmony—reads like a list of the most important concepts underlying the Leibnizian conception of the metaphysical structure of the universe. Moreover, Leibniz’s universe, far from being a universe without God—because, as Clarke insinuated, it does not need intervention from God—is a universe which in its deepest ontological fabric is interwoven with the presence of God. 相似文献
10.
在王锡阐(1628—1682年)有关天体运行的3篇文献《历说.五》、《日月左右旋问答》和《五星行度解》的基础上,分析了王锡阐改上三星本天之行为左旋的原因,揭示了《晓庵新法》中以地心为心的五星运动模型和《五星行度解》中的类第谷体系之间的关系,探讨了王锡阐对第谷模型进行修正的原因。 相似文献