Sunday, July 26, 2015

wang 世界确实只是“真空”的一个小的“线性起伏”。而对于“线性响应”来说, the laws of Newton, Schroedinger, Einstein and others we can observe that they are all second order degree differential equations, ordinary or partial

[PDF]Stokes' Theorem
math.harvard.edu/~ytzeng/worksheet/1121_sol.pdf
Harvard University
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To use Stokes' Theorem, we need to first find the boundary C of S and figure out how it .... The plane z = x + 4 and the cylinder x2 + y2 = 4 intersect in a curve C.


Pauls Online Notes : Calculus III - Stokes' Theorem

tutorial.math.lamar.edu/Classes/.../StokesTheorem.aspx
Lamar University
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In this section we are going to take a look at a theorem that is a higher dimensional version of Green's Theorem. In Green's Theorem we related a line integral to ...


[PDF]1 Statement of Stokes' theorem 2 Examples

www.math.uiuc.edu/.../Math241_168_Stokes...
Department of Mathematics
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Stokes' theorem claims that if we “cap off” the curve C by any surface S (with ..... Let S is the part of the cylinder of radius R around the z-axis, of height H,.


[PDF]The History of Stokes' Theorem

www.ingelec.uns.edu.ar/asnl/Materiales/Cap03Extras/Stokes-Katz.pdf
Gauss then denotes by d2 an element of the y -z plane and erects a cylinder .... The final theorem of our triad, Stokes' theorem, first appeared in print in 1854. ..... not again until Erich Kahler reintroduced it in his 1934 book Einfiihrung in die ...


[PDF]The History of Stokes' Theorem

www.math.ups.edu/~martinj/courses/spring2005/.../stokeshistory_katz.pd...
Apr 9, 2005 - Theorems of Green, Gauss and Stokes ... element of the y -z plane and erects a cylinder above it, this cylinder intersecting the surface in ..... not again until Erich Kahler reintroduced it in his 1934 book Einfiihrung in die Theorie ...


[PDF]Solved Problems - Applied Electromagnetics/6e by Ulaby ...

em.eecs.umich.edu/pdf/ulaby_solved_problems.pdf
by FT Ulaby - ‎Cited by 663 - ‎Related articles
Fawwaz T. Ulaby, Eric Michielssen, and Umberto Ravaioli, Fundamentals of Applied Electromagnetics ...... Verify Stokes's theorem for the vector field B = (r cosφ + ..... A cylinder-shaped carbon resistor is 8 cm in length and its circular cross ...


Use Stoke's theorem to evaluate the integral? | Yahoo Answers

https://answers.yahoo.com/question/index?qid...
Apr 30, 2011 - Use Stoke's theorem to evaluate ∫∫S curlFdS where F(x,y,z) = -2yz i + ... z = x^2+y^2 that lies inside the cylinder x^2+y^2=1, oriented upward.
 
 
 

Why are most of the fundamental laws in Physics second order degree differential equations?

If we look at the laws of Newton, Schroedinger, Einstein and others we can observe that they are all second order degree differential equations, ordinary or partial. Why such a coincidence? Is this an indicator that our projection of reality is just a linear projection or is it something deeper behind this universality of the 2nd degree?
    Be the first to comment!
    • Demetris Christopoulos
      @ Demetris Christopoulos Stokes applies to magnetic field, current loop, propellers in Hydro- and Aerodynamics and Alcubierre drive. Is the same math. Why?! Check this link: https://www.facebook.com/NewPhysicsPage/posts/728332147260113
      7 months ago
    • Demetris Christopoulos
      @Stuart Marongwe, Hawking reaches slowly the same conclusions in his last paper, Erik Verlinde treats the same topic in his "Entropic Gravity" theory papers, I've "discovered" independently (back in '92) the thermodynamic cause of gravity but the first was Fatio Deduillier more than 300 years ago who had first the idea which was promoted later by Georges-Louis Le Sage.
      http://en.wikipedia.org/wiki/Le_Sage%27s_theory_of_gravitation
      7 months ago
    • Demetris Christopoulos
      Entropic gravity might work near black holes, but does not work in the vicinity of elementary particles.
      7 months ago
    • Demetris Christopoulos
      If you investigate Dirac's equation in quaternionic format, then you see immediately the similarity with fluid dynamics equations.

      Φ, ψ and φ are differentiable quaternionic functions (DQF's).
      ALL continuous quaternionic functions that can be differentiated obey this coupling equation:
      Φ = ∇ψ = m φ
      ∇={∂/∂τ, ∂/∂x, ∂/∂y, ∂/∂z}
      ∇ is the quaternionic nabla. m is the coupling factor.

      ||ψ||² =∫|ψ|² dV= 1
      ||φ||² =∫|φ|²dV= 1
      ||Φ||² =∫|Φ|² dV= ∫|∇ψ|² dV= m²

      In quaternionic format the Dirac equation for the free electron runs ∇ψ = m ψ*
      The Dirac equation for the free positron runs ∇*ψ* = m ψ

      Φ = ∇ψ represents a differential continuity equation
      7 months ago
    • Demetris Christopoulos
      Dear Costel, the fact that Divergence Theorem is a special case of Stokes theorem is sufficient for the classification. (Your mentioned link is too 'Einsteinian' for my tastes...:))
      7 months ago
    • Demetris Christopoulos
      Here are two versions of wave equations. They both describe how wave fronts proceed. Huygens principle is based on the Maxwell version.

      Maxwell-Minkowski based approach versus Hamilton-Euclidean based approach
      The difference between the Maxwell-Minkowski based approach and the Hamilton-Euclidean based approach will become clear when the difference between the coordinate time t and the proper time τ is investigated. This becomes difficult when space is curved, but for infinitesimal steps space can be considered flat. In that situation holds:
      Coordinate time step vector = proper time step vector + spatial step vector
      Or in Pythagoras format:
      (∆t)² = (∆τ)² + (∆x)² + (∆y)² + (∆z)²
      This influence is easily recognizable in the corresponding wave equations:
      In Maxell-Minkowski format the wave equation uses coordinate time t. It runs as:
      ∂²ψ/∂t²−∂²ψ/∂x²−∂²ψ/∂y²−∂²ψ/∂z²=0
      Papers on Huygens principle work with this formula or it uses the version with polar coordinates.
      For 3D the general solution runs:
      ψ =f(r−ct)/r, where c=±1; f is real
      For 1D the general solution runs:
      ψ =f(x−ct), where c=±1; f is real

      For the Hamilton-Euclidean version, which uses proper time τ, we use the quaternionic nabla ∇:
      ∇={∂/∂τ, ∂/∂x, ∂/∂y, ∂/∂z}=∇₀+▽; ∇*=∇₀−▽
      ∇ψ = ∇₀ ψ₀ – (▽,Ψ) + ∇₀ Ψ + ▽ ψ₀ ± ▽ × Ψ
      The ± sign reflects the choice between right handed and left handed quaternions.
      In this way the Hamilton-Euclidean format of the wave equation runs:
      ∇*∇ψ = ∇₀∇₀ψ +(▽,▽)ψ =0
      ∂²ψ/∂τ²+∂²ψ/∂x²+∂²ψ/∂y²+∂²ψ/∂z²=0
      Where ψ= ψ₀+Ψ
      For the general solution holds: f= f₀+F
      For the real part ψ₀ of ψ:
      ψ₀ =f₀ (î r−c τ)/r, where c=±1 and î is an imaginary base vector in radial direction
      For the imaginary part Ψ of ψ:
      Ψ = F(î z−c τ), where c=±1 and î= î(z) is an imaginary base vector in the x,y plane
      The orientation θ(z) of î(z) in the x,y plane determines the polarization of the 1D wave front.


      Quaternionic coordinate data, which are based on proper time τ, fit as eigenvalues in Hilbert spaces. This is not the case for the spacetime coordinates that are based on coordinate time t. Hilbert spaces require that their eigenvalues are members of a division ring. Only three suitable division rings exist: real numbers, complex numbers and quaternions.

      The formula:
      (∆t)² = (∆τ)² + (∆x)² + (∆y)² + (∆z)²
      indicates that the coordinate time step corresponds to the step of a full quaternion, which is a superposition of a proper time step and a spatial step.

      An infinitesimal spacetime step ∆s is usually presented as an infinitesimal proper time step ∆τ.

      (∆s)² = (∆t)² - (∆x)² - (∆y)² - (∆z)², with signature + - - - .

      Above it is indicated that the coordinate time step ∆t corresponds to a quaternionic step. It mixes progression and 3D space. Proper time corresponds to pure progression.

      Thus, if spacetime expands (proper time expands) than progression expands.
      This does not say that space does not expand in the same way. (However, due to constant speed of information transfer c, it probably does expand in the same way)


      In this way it might become clear that the choice for starting with Maxwell equations puts contemporary physics models in the direction of spacetime with Minkowski signature {(∆s)² = (∆t)² - (∆x)² - (∆y)² - (∆z)²}, while a choice for the quaternionic approach puts the model developer in the direction of a Euclidean space-progression model. {(∆t)² = (∆τ)² + (∆x)² + (∆y)² + (∆z)²}
      7 months ago
    • Demetris Christopoulos
      Using quaternions we encode the "electric charge" into chiral flow (momentum and angular momentum). Wavefunction ψ better be considered as density of angular momentum. ψ -right handed (for e-) and ψ* left handed (for e+). For a while I am considering the possibility that electric charge too is only apparent as the result of a thermodynamic process as the gravity in "entropic gravity". There's no "free electron" per se but we can considering a chargeless Parson magneton - in fact a simple right handed ring vortex of chargeless matter as the fermion in the the fermionic field ψ (spin -1/2) and left handed ψ* as the anti fermion field spin 1/2) . Pairing fermion and antifermion into a boson field of spin 1 gives us the electromagnetic field (like the Peccei-Quinn "axion" or to be more original: simple buttons) and pairing 2 bosons with opposite spin orientation gives us the gravitational field of spin 0. I think this is the best representation of relationship between fermions, bosons and gravitational field. When it comes to high energy physics and QCD it must be a better way than 3 charges representation because I don't have 3 hands! :) . I suggest for weak force the comparison with separating two anti chiral ring vortices and for strong force the tearing apart of one such ring vortex. Again, when it comes to electron inside of an atom, do not consider it as pointlike separate electrons but rather as a continuous cloud of matter with a certain dynamic distribution of angular momentum density and orientation. Atomic spectra is done by the modes of vibration of a fluid dynamic system composed of just 2 opposite chirality ring vortices. An atom (and a boson) would look like a spiral galaxy. I think the hydrogen atom has a simple enough spectrum to try to recreate it with this classical model. But nobody likes Navier-Stokes! :)
      This simple toy model has the advantage that could be reproduced at any scale from infinite small to infinite big in steps - at the upper scales at which the atoms (or galaxies) of the lower scale become "axions" (for the considered "upper scale").
      7 months ago
    • Demetris Christopoulos
      To me, the "charge" is the apparent result of the dynamics of chargeless matter and the "elementary charge" is the result of confirmation bias and compulsive behavior. Thank you Mr. Millikan!
      "Antimatter" is just ordinary matter whose dynamics has opposite handedness. Dirac eq. shows the perfect symmetry but only we humans try to "spontaneously break it" :).
      7 months ago
    • Demetris Christopoulos
      A photon could be described as a collective partial polarization of the spins of "axions" that move with the mean speed c - Those moving "buttons" could very well describe the electromagnetic field and every electromagnetic phenomena. I have an interesting hydrodynamic model of "electromagnetic induction" - the last thing that gave me headaches and the solution was so simple! Headaches didn't end because I try to find the best way to put all above ideas into a single math framework. Navier-Stokes model flows, Schroedinger models vibrations but I need some advice on criticality - phase transitions. Creation and annihilation operators work for modeling transitions from one vibration mode to another and "I've got the feeling" that could be used as well for matter phase transitions.
      7 months ago
    • Demetris Christopoulos
      Data from LHC, if interpreted according to the model described above, could give the critical points on the scale of energy density.



    如果要改变真空中的光速,必须推翻电动力学的Maxwell方程组。这只有在“真空”成为“非线性介质”的时候才能做到。因为Maxwell方程组实际是“真空本底”上小的“起伏”(Fluctuation)之“线性描述”的最一般形式



    物理学之《2012》——物理学基本规律的非线性? 精选
    已有 4224 次阅读 2011-12-30 11:56 |个人分类:学海无涯|系统分类:科研笔记|关键词:物理学 中微子 超光速 非线性
    盘点2011年物理学界(乃至科学界)的大事,排在首位的应该是OPERA实验组的“超光速中微子”。
     
    如果这个实验结果站得住,那就是当代物理学理论基础的《2012》。
     
    下面是《公共物理学导论》的2.6节。原来没有打算贴的。昨天听马伯强教授关于中微子超光速问题的学术报告。觉得这里的一些想法也许有一点启发性。先贴出来供有兴趣的人参考。
     
    笔者一直有这样一个看法:
     
    1)现在的物理学基本理论都是线性的:
     
    我们熟悉的所有“基本”物理方程:Newton定律、Hamiltonian方程组、Maxwell方程组、Schrödinger方程、Dirac方程。。。,这些描述单个粒子或者“单一”场(指在经典理论中没有被Fourier分解,或者在量子理论中没有被“量子化”的)的方程都是线性的。
     
    非线性来自粒子之间、场分量(经典的语言就是不同的“模”、量子的语言就是不同的“场量子”)之间的相互作用,而不是物理学基本方程本身。(而且二体相互作用往往可以约化成单体运动,所以一定要有“第三者插足”!才能使得事情变得complicated! )
     
    2)“好”的理论不仅是线性的,而且是时空一阶导数的
     
    Newton方程在量子力学中就受到Heisenberg不确定性的限制——因为时间二阶导数项,所以被Schrödinger方程代替;而Schrödinger方程的Hamiltonian算子里有空间的二阶导数项,所以有Dirac方程。
     
    而Hamiltonian方程组尽管是在经典力学里得到的,却“放之四海而皆准”,就是因为这组方程是时空一阶导数的!
     
    这非常强烈地暗示着:我们的物理世界只是一个非常“大”的“本底”上的小小的“起伏”(fluctuation),而且这个起伏并不“剧烈”,所以连时空的高阶导数都可以忽略!
     
    这个“本底”,应该就是我们所说的“真空”!
     
    但是,如果这些时空高阶导数不能忽略(特别小的时空尺度,剧烈变化的物理过程),甚至非线性性质(即“本底”——“真空”本身的性质)显现出来了呢?——不是没有人想过,比如:P. A. M. Dirac,Nature 168 (1951) 906
     
    那就是现有的物理学方程性质的破坏——《2012》,和新的理论的建立——一场新的物理学革命?
     
      =========
     
    《公共物理学导论讲义》: 2.6 物理学规律的相对论不变性
     
          物理学规律的另一个重要的不变性是:物理学规律不因为坐标系选取的不同而改变——这就是物理学规律的相对论不变性。(用物理学的语言来说,就是物理学规律是关于相对论坐标变换“协变”。)这也是自然界和人类社会所有客观规律必须满足的不变性——规律不因为你人为选择的“视角”或者“立场”而改变。如果坐标系是惯性系,这就是“狭义相对性原理”,如果是任意坐标系,则是“广义相对性原理”。
     
          这个简单的道理,直接导致了Einstein的相对论理论。真空中的光速不随坐标系选取而改变,只是这个不变性的直接结果,而不是狭义相对论的另一个出发点(所谓“光速不变原理”)。如果要改变真空中的光速,必须推翻电动力学的Maxwell方程组。这只有在“真空”成为“非线性介质”的时候才能做到。因为Maxwell方程组实际是“真空本底”上小的“起伏”(Fluctuation)之“线性描述”的最一般形式。根据宇宙“大爆炸”模型,我们的物质世界是在宇宙大爆炸的初期从“真空”中“激发”出来的。根据最近的天文学观测结果,理论物理学家们推测:即使这个“激发”出来的、与“真空”相比是一点点“小量”的物质世界,也主要是“暗物质”与“暗能量”组成的——75%是“暗能量”、21%是“暗物质”、其余4%才是我们能够观测到的“普通物质”。所以,我们能够观测到的“普通”物质组成的世界确实只是“真空”的一个小的“线性起伏”。而对于“线性响应”来说,其“响应系数”只描述“本底”(这里是“真空”)的“零阶”性质,与“起伏”或者“扰动”无关。这就是所谓“线性响应理论”。关于线性响应的理论,我们会在下一章介绍。

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