What is Lorenz: Definition and 57 Discussions

Konrad Zacharias Lorenz (German pronunciation: [ˈkɔnʁaːt ˈloːʁɛnts] (listen); 7 November 1903 – 27 February 1989) was an Austrian zoologist, ethologist, and ornithologist. He shared the 1973 Nobel Prize in Physiology or Medicine with Nikolaas Tinbergen and Karl von Frisch. He is often regarded as one of the founders of modern ethology, the study of animal behavior. He developed an approach that began with an earlier generation, including his teacher Oskar Heinroth.Lorenz studied instinctive behavior in animals, especially in greylag geese and jackdaws. Working with geese, he investigated the principle of imprinting, the process by which some nidifugous birds (i.e. birds that leave their nest early) bond instinctively with the first moving object that they see within the first hours of hatching. Although Lorenz did not discover the topic, he became widely known for his descriptions of imprinting as an instinctive bond. In 1936 he met Tinbergen, and the two collaborated in developing ethology as a separate sub-discipline of biology. A Review of General Psychology survey, published in 2002, ranked Lorenz the 65th most cited scholar of the 20th century in the technical psychology journals, introductory psychology textbooks, and survey responses.Lorenz's work was interrupted by the onset of World War II and in 1941 he was recruited into the German Army as a medic. In 1944, he was sent to the Eastern Front where he was captured by the Soviet Red Army and spent four years as a German prisoner of war in Soviet Armenia. After the war, he regretted his membership of the Nazi Party.Lorenz wrote numerous books, some of which, such as King Solomon's Ring, On Aggression, and Man Meets Dog, became popular reading. His last work "Here I Am – Where Are You?" is a summary of his life's work and focuses on his famous studies of greylag geese.

View More On Wikipedia.org
  1. patric44

    I What is the origin of Lorenz force?

    hi guys one of my friends asked me about the origin of the electromagnetic induction, I know somehow that its related to the Lorenz force as the electrons in the conduction band of say the coil interact with the magnetic field ,which results in separation of electrons and positive ions which...
  2. D

    B Lorenz COP of a heat pump and the temperatures of the hot/cold reservoirs

    @Dale : “The COP of a heat pump and the efficiency of a heat engine both depend strongly on the temperatures of the hot and cold reservoirs. For this calculation you need to go back and check the sources for the temperatures corresponding to each of these numbers. You will find that the Stirling...
  3. O

    I The Trapping Region of the Lorenz equations

    I was dealing with nonlinear systems of differential equations like the Lorenz equations (https://en.wikipedia.org/wiki/Lorenz_system). Now there is a trapping region of this system defined by the ellipsoid ρx^2+σy^2+σ(z-2ρ)^2<R. I wondered how this region is found and I found out that a...
  4. T

    A Magnitude 4-Vector Lorenz Gauge: Klein-Gordon Eq.

    The Klein-Gordon equation is based on the relation (E-eΦ)2-(pc-eA)2=m2^2c2, which is the magnitude of the difference between the momentum four-vector and the four-potential. Since the magnitude of the momentum four-vector is given by E2-p2c2=m2c4, does it follow that the magnitude of the...
  5. L

    I Lorenz gauge, derivative of field tensor

    Fμν = ∂μAν- ∂νAμ ∂μFμν = ∂2μAν - ∂ν(∂μAμ) = ∂2μAνWhy ∂ν(∂μAμ) and not ∂μ∂νAμ ? And why does ∂ν(∂μAμ) drop out? thank you
  6. J

    A Question about Lorenz invariance and cluster decomposition

    From Weinberg, The Quantum Theory of Fields, Vol. 1, there is the statement that "the only way" to merge Lorentz invariance with the cluster decomposition property (a.k.a. locality) is through a field theory. He uses this argument basically to justify that any quantum theory at low energies...
  7. K

    Can the equations for two retarded potentials satisfy the Lorenz condition?

    I wonder these equations can satisfy the Lorenz condition?? I mean.. how above equations can satisfy the divergence A + 1/c^2 dϕ/dt =0.
  8. m4r35n357

    Lorenz ODE solver in 35 lines of pure Python

    Features: No external dependencies. Arbitrary order simulation (accuracy limited by float precision). No finite difference errors. Can be extended to arbitrary precision with gmpy2 and two more lines. Enjoy! Parameters: order step size number of steps initial conditions (x, y, z) parameters...
  9. A

    I Lorenz Transformation of Time: Explained

    For example, Lorenz transformation of time means That measurement of time changes from one observer to another. I have read that this means moving clocks run slower. But this can't be true because Lorenz transformation of time depends on both of the seed of the observer and the object he...
  10. G

    Derivation: Maxwell's equation only from the Lorenz gauge

    Hi. Here, somebody apparently derives Maxwell's equations using only symmetry of second derivatives and the Lorenz gauge condition. Unfortunately it's in German, but I think the basic ideas are clear from the maths only. In this derivation, the magnetic field turns out to be divergence-free...
  11. S

    I Understanding Lorenz Gauge Derivation

    Can someone explain to me (or point me towards a source) how is the Lorenz Gauge derived? I am reading the Griffiths book and from what I understand we can do the transformation ##A' = A + \nabla \lambda## and at the same time ##V' = V - \frac{\partial \lambda}{\partial t}## and B and E remain...
  12. Euler2718

    I Can Nonlinear Equations be Linearized Using Free Parameters?

    I am given the equations of Lorenz with respect to deterministic non-periodic flow: \frac{dX}{dt} = Pr(Y-X), X(0)=X_{0} \frac{dY}{dt} = -XZ + rX - Y, Y(0) = Y_{0} \frac{dZ}{dt} = XY-bZ, Z(0) = Z_{0} where Pr is the Prandtl number, r = Ra/Rac is the ratio of the Rayleigh number to its...
  13. DavideGenoa

    Proving Lorenz Gauge Choice: A Getty's Physics Exploration

    Hello, friends! My textbook, Gettys's Physics, says that the Lorenz gauge choice uses the magnetic vector potential $$\mathbf{A}(\mathbf{x},t):=\frac{\mu_0}{4\pi}\int \frac{\mathbf{J}(\mathbf{y},t-c^{-1}\|\mathbf{x}-\mathbf{y}\|)}{\|\mathbf{x}-\mathbf{y}\|}d^3y $$and the electric potential...
  14. T

    I Lorenz Curves and Distributions....

    Is it correct to say that the Lorenz curve is the normalized integral of the quantile function with respect to the x-axis?
  15. F

    Lorenz system directions of fastest growth

    Homework Statement A Lorenz system is given by x' = sy - sx y' = 3sx - y - xz z' = xy - bz In the vicinity of point x = y = 2s, z=4s , for s>>b, show motion is aligned with the y,z plane (sub these values in and x' is 0). By considering the evolution of vectors [2,0,1+sqrt(5)] , [0,1,0]...
  16. carllacan

    I Lyapunov coefficient of Lorenz System

    Hi. I'm trying to get the Lyapunov coeficient for a Lorenz System (namely, a laser, using the Lorenz-Haken model) but I'm not getting the plots that would be expected. This is how two trajectories with near identical initial conditions behave (only one of the variables): And here's the...
  17. I

    Do Wind Turbines Significantly Alter Weather Patterns?

    As more wind turbines are installed worldwide, I was wondering how much of an impact on weather they could/would have. (Full disclosure: I am not trained, merely an interested non-scientist) Collectively, wind turbines are collecting considerably more energy than Lorenz's butterfly, so could...
  18. A

    B Solving Special Relativity Problems: Interval vs Lorenz Equations

    Why is it that in SR we always seem to jump to the Lorenz equations when there is a simpler way. This is the concept of an interval. The interval is defined as the square root of ( T squared minus X squared) . In Special relativity the time and distance are different for different...
  19. N

    Refrigeration: Coefficient of Performance (Carnot & Lorenz)

    Homework Statement Cooling of a food from 293K (20 ⁰C), freezing it at 272K (-1⁰C), and further cooling to 253K (-20 ⁰C); using cooling water rising in temperature from 293K (20 ⁰C) to 303K (30 ⁰C) to accept heat. The specific heat of the unfrozen food is taken as 3.2 kJ/kg K, that of the...
  20. CharlesJQuarra

    Verifying Simple Quadrupole Field Not in Lorenz Gauge?

    I'm having trouble reproducing some of the results regarding gravitational waves in the Wald's General Relativity In section 4.4 of gravitational radiation, eq.4.4.49 shows the far-field generated by a variable mass quadrupole: $$ \gamma_{i j}(t,r)=\frac{2}{3R} \frac{d^2 q_{i j}}{dt^2}...
  21. D

    MHB Lorenz Attractor: Questions & Answers

    I have 2 questions about the Lorenz attractor: 1)Is the Lorenz attractor considered to be a fractal set? 2)If it is so, then what is its topological dimension? Thanks.:)
  22. F

    Chaos and the Lorenz Equations

    Take the Lorenz equations x'=σ(y-x) y'=rx-y-xz z'=xy-bz with σ=10, b=8/3 and r=28 as a typical example of chaos (I am using primes to indicate total time derivatives in this post). A basic property of a chaotic system (where the flow in phase space is a strange attractor) is that if you pick...
  23. valentin mano

    Can objects contract faster than the speed of light?

    A highly accelerated object near the speed of light,should be seen contracting faster,than the speed of light.Maybe the contraction could not be observed?
  24. SpiderET

    Lorenz covariance vs proofs of relativity theory

    I have been studying history of relativity theory and now it seems to me, that it is wrong to automatically assume that proofs of Lorentz covariance are proofs of Special relativity theory. It seems to me, that there is broader group of theories, that are compatible with Lorentz covariance but...
  25. D

    Does change in Lorenz contraction w/ respect to time = Lorenz Velocity

    Length contraction velocity question. Suppose there are two sets of binary neutron stars in mirrored synchronous orbits one light year apart with zero differential velocity between the orbits center of mass. Both sets of binary stars are orbiting very fast causing velocities with respect...
  26. Y

    Question on Coulomb and Lorenz Gauge

    This is Problem 10.6 in page 422 of "Introduction to Electrodynamics" Edition 2 by David Griffiths. The question is: Which of the potentials in the following is in the Coulomb gauge? Which is in Lorenz Gauge?( Notice that these gauges are not mutually exclusive.) This is what the solution...
  27. R

    What are the physical applications of Lorenz and Coulomb gauge?

    i am searching the physical significance of lorenz and coloumb gauge but can't find anything besides that coloumb gauge is used for finding time independent potentials while lorenz is for finding time dependent potentials. and i'll be really grateful if u give me applications of then in any field.
  28. M

    Can an Ellipsoidal Region Contain All Trajectories of the Lorenz Equations?

    Homework Statement Show that there is a certain ellipsoidal region E of the form rx2 + σy2 + σ(z-2r)2 ≤ C such that all trajectories of the Lorenz equations eventually enter E and stay in there forever. Homework Equations Lorenz Equations: \dot{x} = \sigma (y - x) \dot{y} = rx -...
  29. C

    Vacuum expectation value and lorenz (trans) invariance

    Hi! I've seen it stated that because of Lorenz and translational invariance \langle 0| \phi(x) |0 \rangle has to be a constant and I wondered how to formally verify this?
  30. 0

    Action = reaction and lorenz force

    Newtons third law states that there is a counter force to every force. Unfortunately this doesn't seem to work for moving point charges. The Coulomb force cancels out but the B-Field of a moving point charge is: \mathbf{B}=\frac{\mu_0}{4\pi}q...
  31. A

    Lorenz Curve: CI=0.99 - Describe Graph, Comment on Income

    Lorenz Curve question. HELP HELP! Urgent? If a country has a coefficient of inequality (CI) of 0.99, describe the graph of the Lorenz function in relation to the line y=x. Hence comment on the income distribution.
  32. J

    Maxwell equations in Lorenz gauge

    In the Lorenz gauge, the Maxwell equations reduce to four inhomogenous wave equations, with the charge density acting as the source for V, and the current density for A. For now, just take a static charge distribution -- say, a point charge at the origin. It is well known that a static...
  33. P

    Understanding Lorenz Equations & Stability: A Homework Guide

    Homework Statement http://imageshack.us/photo/my-images/535/newpicture3.jpg/ Homework Equations Honestly i used the equation in Strogatz 10.3.3 so I am not sure how to do it for others. The Attempt at a Solution http://imageshack.us/photo/my-images/406/worke.png/...
  34. T

    Lorenz transformations for two parallel inertial systems

    Thanks for reading! Homework Statement I have been given a proof for the lorentz transformations (which I only partly understand) that relied on the two relativity postulates (equivalence of inertial systems and the speed of light being constant) for the case of two standard inertial...
  35. I

    Is This Simulation a Real-Time Visualization of the Lorenz Attractor?

    I have created a physics simulation for the famous Lorenz Waterwheel that also graphs its velocity, acceleration, and water distribution in real time. Thus, the Lorenz attractor emerges. https://www.youtube.com/watch?v=http://www.youtube.com/watch?v=9VwQhF7tjoQ I posted this here...
  36. P

    Lorenz velocity transformation

    Homework Statement the particles in a high energy accelerator experiment are approaching each other head on, each with speed of 0.9520c as measured in laboratory. what is the magnitude of the velocity of one particle relative to the other? Homework Equations vx = vx' + u / 1 + (uvx' /...
  37. Z

    Lorenz attractor&calabi-yau space

    The string theory is believed to take the form of a Calabi–Yau manifold. But the exact shape is not yet known. Is there any possibility that Lorenz attractor equations can define its shape?
  38. L

    Lorenz guage and equation of continuity

    π²³ ∞ ° → ~ µ ρ σ τ ω ∑ … √ ∫ ≤ ≥ ± ∃ · θ φ ψ Ω α β γ δ ∂ ∆ ∇ ε λ Λ Γ ô Homework Statement Show that Lorentz' gauge equation ∇.A = -µ(jωε+σe)φ is the equation of continuity ∇ .Ji = (jωε+σe)/ε P(R) Homework Equations The Attempt at a Solution I tried taking curl, div of...
  39. N

    Lorenz Equations: Explaining Apparent Unpredictability

    It's not clear to me why the Lorenz model shows us that the apparent unpredictability of turbulent fluid dynamics is deterministic. Can anyone explain?
  40. M

    What Are the Degrees of Freedom in Lorenz and Columb Gauges?

    My teacher told me that in columb gauge we have div A = 0 along with d/dt(Ao) = 0 where A is the vector potential and Ao is its time component , and time & space are not on equal footing , so these are two degrees of freedom and in lorenz gauge we have 4 dimensional divA = 0 where space & time...
  41. D

    Is the bulldog's nose a survival trait or a product of human engineering?

    I started to read a bit of Konrads Lorent work, since he was pointed to me in this thread by Andre: https://www.physicsforums.com/showthread.php?p=2437331#post2437331 Ive come across on this...
  42. H

    Solve Lorentz Transformation Homework: Find t When t'=10s

    Homework Statement A clock is moving past us at speed v=\frac{c}{2} reads t^{'}=0 when our clock read t=0. Using the Lorentz tranformation, find out what our clock will read when the moving clock reads 10s. Homework Equations t=\gamma(x^{'}+\frac{Vt^{'}}{c^{2}}) The Attempt at a...
  43. A

    General Lorenz transformation is not group

    Is corretct, that a general lorenz transformation don't satisfaction axioms of group structure? Let, GL(A,B) is general Lorenz transformacion from a frame A to frame B, which B is moveing a velocity V with respect to A. And GL(B,C) is likewise G. L. from B to C. A frame C has a valocity U...
  44. E

    Lorenz Attractors and Trajectories

    Homework Statement I'm using the textbook "Nonlinear Dynamics and Chaos" by Strogratz. So far, it's been terrific. However, I got to the section on the Lorenz attractor and got stuck. The author has a picture and an explanation that eludes me. The picture in question can be seen on this...
  45. A

    Why Can We Freely Choose the Divergence of A in Electromagnetic Theory?

    I understand the concept of a gauge transform, and I understand why it is that the magnetic field would be unchanged with the addition of the gradient of an arbitrary scalar potential onto the magnetic vector potential A, and I understand why the electric field E would be invariant under the...
  46. H

    Homopolar motor teaches about the Lorenz Force

    I have made a new version of Faraday's homopolar motor. This was the first device to demonstrate the connection between electricity, magnetism and motion. Faraday's motor included a beaker of mercury as the outer conductor. This has been demonstrated in classes. My motor comprises gold-plated...
  47. G

    Lorenz (stability with Liapunov function)

    Homework Statement Using the Liapunov function V=1/2(x^2+\sigma y^2 + \sigma z^2), obtain conditions on sigma, rho, beta sufficient for global asymptotic stability of the origin in the Lorenz equation. Homework Equations The Lorenz equation \dot{x}=\sigma (y-x); \dot{y}=\rho...
  48. D

    Does Lorentz Contraction Affect Perceived Distances at Near-Light Speeds?

    If I am watching spherical mass A that is traveling away from me at close to light speeds it lorenz contracts like I am looking down at a plate. Does the distance mass A is from me contract also or does it stay the same distance away ?
  49. turbo

    News Edward Lorenz RIP: Father of Chaos Theory Dies at 90

    I didn't know where to put this notice, but the father of chaos theory died yesterday at his home in Cambridge at the age of 90.
  50. A

    How can I solve for A in the Lorenz Gauge with a static source?

    I've gotten out most of this question, it's really just the last part that's getting to me at this stage. I'd never seen the http://mathworld.wolfram.com/DeltaFunction.html" before so it might be because of that. I've an idea how to do it but I just end up in a mess of partial derivatives. I'd...