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11.
Helmholtz electrically induced extra mass inside a charged hollow sphere, recently evidenced by Mikhailov, is analogous to Machs inertial mass. Existence of a corresponding magnetically induced extra mass in an electron flying around an autistic magnet is derived. The overall electro-magnetic effect can be covariantly expressed.  相似文献   
12.
In the summer of 1916, Finnish physicist Gunnar Nordström (1881–1923) arrived in Leiden to carry out research with Paul Ehrenfest (1880–1933), Hendrik A. Lorentzs successor in the chair of theoretical physics. Nordström had recently published the first five-dimensional unified model of the universe, a theory that went virtually unnoticed by the physics community. Ehrenfests personal journals reveal that Nordströms visit coincided with a flowering of Ehrenfests own interest in dimensionality, which resulted in his well-known paper on the connection between the fundamental laws of physics and the three-dimensionality of space. I examine Nordströms and Ehrenfests collaboration and explore the relationship between their ideas and the Kaluza-Klein model of five-dimensional unification.Paul Halpern is Professor of Physics at the University of the Sciences in Philadelphia. He received a Guggenheim Fellowship in 2002 to study the history of dimensionality in science.  相似文献   
13.
Auguste Besson 《Pramana》2004,62(3):537-540
The RunII of the Dø experiment was started in March 2001. The first preliminary results on searches for new physics are presented, with a luminosity of ~ 10 pb?1 from the data collected in 2001-2002. We report results in mSUGRA (jets + missingEt channel), GMSB (diphotons), RPV (trileptons and like sign dileptons) and large extra dimensions (dielectrons and diphotons).  相似文献   
14.
In the minimal universal extra dimension model, single production of n = 2 gauge bosons provides a unique discriminating feature from supersymmetry. We discuss how the proposed international linear collider can act as a n = 2 factory, much in the same vein as LEP.   相似文献   
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为了获取长距离超细激光束,采用几何能量守恒法设计出一种衍射光学元件,推导出高斯光入射时衍射光学元件位相函数。根据建立的数学模型,设计超细激光束准直器,并模拟高斯光入射时出射激光束的光斑形状及光强分布,最后计算了能量利用率。  相似文献   
17.
The adulteration of extra virgin olive oil with low-quality and inexpensive seed oil is a serious problem in the industry. In recent years, the characterization of extra virgin olive oil adulteration with various techniques has been successfully implemented. In this work, a comparative study of Raman and visible spectroscopy is presented. These methods are rapid, noninvasive, and no sample pretreatment is required. We used both methods to study Cretan extra virgin olive oil adulterated with sunflower oil. Statistical analysis based on partial least square regression was used to determine the detection limits of the methods. Raman spectroscopy was superior in comparison to visible spectroscopy with adulteration detection limits of 3.5 and 5.5%, respectively, for the same samples. These results indicate that both techniques are suitable for olive oil quality control.  相似文献   
18.
The sensitivity of the ATLAS detector to the discovery of a heavy charged Higgs boson is presented. Assuming a heavy SUSY spectrum, the most promising channels above the top quark mass are H±tb and H± → τ±ντ which provide coverage in the low and high tanβ regions up to ∼ 600 GeV. The achievable precisions on the charged Higgs mass and tanβ determination are also discussed. The H±W± h0 channel, though restricted to a small MSSM parameter space, shows a viable signal in NMSSM where the parameter space is less constrained. The observation of the channel H → τL ντ + c.c. may constitute a distinctive evidence for models with singlet neutrinos in large extra dimensions.  相似文献   
19.
首先推出了铁磁晶体在弱外场作用下定态磁化参量,用斜率比较法分析了直接影响磁化取向的参量-平均场的取值情况,讨论了弱外场对定态磁化参量的影响机制,结果发现:①在弱外场较小时,系统与无外场时的情况类似,也有两个稳定取向和一个不稳定取向;如弱外场约大于自旋相互作用,则系统只有一个沿外场方向的稳定取向;②在外场比较弱的情况下,平均场可表示为外场的线性关系;③当平均场取下值点时,所有的N+和N-随弱外场变化的两条曲线相交于坐标轴的左边,磁化强度比的零点左移,外施磁场越大,交点越趋近于A点;当平均场取上值点时,所有的N+和N-随弱外场变化的两条曲线相交于坐标轴的右边,磁化强度比的零点右移,外施磁场越大,交点越趋近于A点.  相似文献   
20.
大型沉井结构是当今应用较广的基础工程,由于沉井结构的规模大,工区土层复杂,存在有许多不确定性因素。使得施工过程的力学模型比较难确定。迄今尚缺乏可供借鉴的理论研究。由于施工的关键是保证沉井的均匀下沉,控制终沉和防止突沉,为此,建立合适的施工力学模型以预测下沉量和开挖量之间的关系就十分必要,考虑到混凝土沉井在土体中下沉时,其本身的变形很小,可以忽略其影响,本文从多自由度刚体运动的角度,建立沉井下沉过程的动态力学模型。为验证所建模型的正确性,本文对一实际工程进行了数值仿真计算。并将计算结果与实测结果进行了对比。结果表明,所建立的力学模型能较好地反映沉井下沉的工程实际,因而可以应用该模型对沉井下沉进行预测分析。从而有助于指导沉井的实际施工。  相似文献   
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