What is Conditions: Definition and 1000 Discussions

In mathematical optimization, the Karush–Kuhn–Tucker (KKT) conditions, also known as the Kuhn–Tucker conditions, are first derivative tests (sometimes called first-order necessary conditions) for a solution in nonlinear programming to be optimal, provided that some regularity conditions are satisfied.
Allowing inequality constraints, the KKT approach to nonlinear programming generalizes the method of Lagrange multipliers, which allows only equality constraints. Similar to the Lagrange approach, the constrained maximization (minimization) problem is rewritten as a Lagrange function whose optimal point is a saddle point, i.e. a global maximum (minimum) over the domain of the choice variables and a global minimum (maximum) over the multipliers, which is why the Karush–Kuhn–Tucker theorem is sometimes referred to as the saddle-point theorem.The KKT conditions were originally named after Harold W. Kuhn and Albert W. Tucker, who first published the conditions in 1951. Later scholars discovered that the necessary conditions for this problem had been stated by William Karush in his master's thesis in 1939.

View More On Wikipedia.org
  1. A

    Boundary conditions and time domain electromagnetic waves

    Boundary conditions & time domain electromagnetic waves: does classical model fit? Consider two propagating media: a lossy dielectric medium and a lossless dielectric medium. Thus, the interface that separates them has two tangential components of electric field, one for each medium. One of...
  2. I

    Boundary conditions for Laplace's equation

    I don't seem to grasp the meaning of boundary conditions for Laplace's equation. Consider the Lagendre expansion of the potential at x due to a unit charge 1/|x-x'|, where x' is the position of the unit point charge. To do the expansion, we need to consider a volume in space where the...
  3. L

    How does formic acid (under basic conditions) convert to CO2?

    What is the mechanism that results in formic acid quickly converting to CO2. I know this happens under basic conditions so I'm assuming the first step is forming the formate ion.
  4. H

    Solving Schrodinger's Eqn for Quantum Ring: Boundary Conditions?

    When solving Schrodinger's eqn for a quantum ring, what would be the boundary conditions? The solution (polar) should be Ψ(Φ) = A exp(ikΦ) + B exp(-ikΦ) And I believe the boundary conditions are Ψ(0) = Ψ(2pi) Ψ(0) = A + B Ψ(2pi) = A exp(ik*2π) + B exp(ik*2π) and I suppose I can...
  5. R

    Numerical Boundary Conditions for Fokker Planck and Kramers equations

    Hi Everyone, Apologies if this is posted in the wrong place. I am trying to produce numerical solutions for the following initial value partial differential equations, namely the overdamped Schmoluchowski equation \frac{\partial p(x,t)}{\partial t}=-\frac{\partial}{\partial...
  6. Z

    Solving PDEs without Boundary Conditions: A Conundrum?

    If a PDE has no boundary conditions specified, how does one go about providing a solution--even if this is a general solution? I'm stuck looking at the separation of variables and other methods which all seem to heavily rely on those boundary conditions and initial conditions. If anyone...
  7. L

    How do the energy conditions in GR relate to timelike and null vectors?

    Hi, Sean Carroll talks about energy conditions in ch4 of his GR book. From what I understand we want to impose co-ordinate invariant restrictions so we need to form a scalar from the energy momentum tensor, which is done by just arbitrarily contracting with timelike/null vectors (why not...
  8. R

    Conservation laws, Noether's theorem and initial conditions

    Hello, everybody! During the whole of my undergraduate study of physics, this one thing always bothered me. It concerns the interplay of conserved quantities, symmetries, Noether's theorem and initial conditions. For a system of N degrees of freedom, governed by the usual Newton's laws...
  9. E

    Initial conditions for rlc series natural response

    Homework Statement Find v(t) across a cap. in a series rlc circuit with no driving force (initial v across cap: 24V) Homework Equations from the values of the components, \alpha > \omega_0, the circuit is overdamped, and the following equation can be used: v(t) =A_1 e^{s_1 t} + A_2...
  10. H

    All conditions are true for a certain range

    How do you specify, in mathematical notation, that a condition is true for all cases? For example, I want to say that t=5 for every value of n. Basically like \lim_{n\to\infty}{t=5}, but instead for every value of n, not just as n approaches infinity. Also, how to specify the range of n...
  11. wolram

    What weather conditions are needed to produce fine snow

    What weather conditions are needed to produce fine snow rather than the big flaky wet snow. .
  12. Y

    Special relativity Only Valid Under Handpicked Conditions?

    Short version: How accurate is this paper: http://www.wbabin.net/ajay/sharma17.pdf Long version: Hello! Physics is not my field of study, but here's my situation: I was having a religious debate and we were discussing the origin of the universe. I decided to quote Lawrence Krauss (a physicist)...
  13. Spinnor

    Klein–Gordon equation with time dependent boundary conditions.

    Klein–Gordon equation with time dependent boundary conditions. Suppose we look for solutions to the Klein–Gordon equation with the following time dependent boundary conditions, psi(r,theta,phi,t) = 0 zero at infinity psi(on surface of small ball, B_1,t) = C*exp[i*omega*t] psi(on...
  14. Spinnor

    Time independent Klein–Gordon equation with boundary conditions.

    Say we consider the time independent Klein–Gordon equation, see: http://en.wikipedia.org/wiki/Klein%E2%80%93Gordon_equation Lets impose the following boundary conditions, the function is zero at infinity and on some small ball of radius R centered on some origin the function is some...
  15. C

    Solving Problem with Derivatives as Initial Conditions

    Homework Statement I've been given equations that have derivatives as initial conditions, rather than things like u(0,t)=u(L,t)=0 Things like this: http://img444.imageshack.us/img444/5082/mathu.th.jpg Uploaded with ImageShack.us Homework Equations The Attempt at a...
  16. J

    Stability conditions of discrete system

    Homework Statement Consider a discrete-time system, driven by: x[k+1] = Ax[k] for non-zero inital conditions x[0] a) write the closed-form solution of x[k]. If the system is asymptotically stable how should x(k) behave? b) what is condition for asymptotic stability? Homework Equations...
  17. H

    Alternative boundary conditions - Thomas-algorithm

    Alternative boundary conditions -- Thomas-algorithm Hello, I have to solve a diffusion equation: MatrixL * Csim(:,i+1) = MatrixR * Csim(:,i) + BoundaryConditions where Csim = concentration, j = location, i = time. Boundary conditions are of type Dirichlet (Csim = 5 at j = 1, Csim = 0...
  18. R

    Fourier transform for loaded string with periodic boundary conditions.

    Homework Statement So we have a string of N particles connected by springs like so: *...*...*...*...* A corresponding Hamiltonian that looks like: H= 1/2* \Sigma P_j^2 + (x_j - x_(j+1) )^2 Where x is transverse position of the particle as measured from the equilibrium position, and...
  19. N

    Steady State 2-D Heat Equation with Mixed Boundary Conditions

    Homework Statement I am trying to solve the Laplacian Equation with mixed boundary conditions on a rectangular square that is 1m x 1m. Homework Equations \nabla2T=0 .....T=500K ....________ ....|@@@@| T=500K...|@@@@|...T=500K ....|@@@@| ....|______.| ....Convection ....dT...
  20. E

    Calc Volume and Temp of gas with changing conditions

    Homework Statement If 18.75 mol of helium gas is at 10.0C and a gauge pressure of 0.035atm, calculate a) the volume of the helium gas under these conditions. b) calculate the temp if the gas is compressed to half the voume at a gauge pressure of 1.00atm. Homework Equations PV=nRT...
  21. Y

    What is the magnetic boundary conditions between air and copper?

    I understand \vec J_{free} only exist on boundary surface of perfect conductors. Copper is close enough and have surface current. Also copper is paramagnetic material which implies \mu_{cu} = \mu_0 or very very close. In order to find the exact angle of the of the magnetic field inside the...
  22. A

    Variable conditions of double slit interference

    Homework Statement Hi Can anyone help on this. The questions is as follows: In a double slits experiment using red light, a fringe pattern is observed on a screen at a fixed distance from the double slits. How would the finge pattern change if: a) The screen is moved closer to the...
  23. PeterDonis

    Conditions for spacetime to have flat spatial slices

    In another thread, https://www.physicsforums.com/showpost.php?p=2973770&postcount=45, some questions came up about what the conditions are for a spacetime to admit flat spatial slices, and for a spacetime to have a time-independent "scale factor" (see definition below). These questions...
  24. J

    Conditions at the Centre of the Earth

    If one could drill a hole to the centre of the earth, presumably the gravitational force on the body would decrease as one passed down this theoretical hole until one could float freely right at the centre where the gravitational force is equal and opposite in all directions with a net effect of...
  25. C

    State Function Conditions in Isothermal, adiabatic

    In an Isothermic and reversible condition why is DH=0? (D=delta) I can understand that DU=0 but DH? but why would DH not change? DH should also =0 if it was an adiabtic and irreversible condition? since DH=dq/T -> as long as there is no heat transfer DH=0? Since it's reversible would...
  26. R

    How Can You Integrate Cot^6(x) Without Using the Reduction Formula?

    Homework Statement Find the integral of cot^6(x) without using the reduction formula. Homework Equations Potentially any trig identities involving the cotangent The Attempt at a Solution I tried splitting up the cot^6 in various ways such as cot^4*cot^2 and cot^2*cot^2*cot*2 but...
  27. L

    Is the Intersection of Two Subspaces Always a Subspace?

    Homework Statement R = { (a+1, b 0) | a, b are real numbers} S = { (a+b, b, c) | a, b, c are real numbers) T = R intersect S I have shown that R and S are subspaces of R^3. Now I have to determine whether T is also a subspace of R^3. The answer provided is that yes, T is also a...
  28. M

    Under what conditions is a pendulum a Simple Harmonic Oscillator, why?

    For part of my lab write up on pendulum motion, my professor wanted us to find out why a pendulum was not a simple harmonic oscillator, and under what conditions it was. He also wanted to show this mathematically. So far what I have is that if there is no damping(friction?) and if the the...
  29. S

    Inflation and initial conditions

    Its been argued that inflation needs the initial conditions to be finely tuned: eg: http://en.wikipedia.org/wiki/Inflation_(cosmology)#Fine-tuning_problem does this paper resolve this problem...
  30. N

    What Conditions Must a Matrix Meet to Be a Density Matrix?

    What are the conditions for some matrix to be a density matrix ? I know of these conditions: 1.) \rho=\rho^{2} 2.) Tr(\rho)=1 (for pure state) Is this all ?
  31. B

    Solve Differential eq with initial conditions

    Homework Statement Solve: \frac{\partial H}{\partial t} = -4\kappa H^{2} With initial condition: H(0) = 1/L^{2} To find: H(t) = \frac{1}{4\kappa t + L^{2}} 2. The attempt at a solution I tried using Taylor series expansion such that: H(t)\approx H(0)+t\frac{\partial...
  32. T

    Thermal Equilibrium: Conditions and Application

    Can one say a body which has the conditions above mentioned be in thermal equilibrium? How does one apply the definition of temperature equilibrium to this situation? (Physically I think it's possible for a body to be in this situation if some part of it receives heat from the outside and...
  33. T

    Slip & Non-Slip conditions for a Cylinder

    Ey guys, this is a problem from my Mech Eng Dynamcis of Machine class I believe i have the solution already since I've spoken to the lecture'r/tutors who run the subject but would like further clarification just incase I've done something completely wrong. This is the problem The...
  34. T

    What Variables are Zero in Different Thermodynamic Conditions?

    Hello Everyone, Is there a list online somewhere of which variable values are 0 and why (conceptually), based on initial conditions? Like I know that for a system at constant volume, w=0. I am looking for a list for the other effects like isothermal, adiabatic, what does pressure= if there is...
  35. X

    Solving for constants given boundary conditions

    Homework Statement http://img843.imageshack.us/img843/3515/11193469.png Homework Equations The Attempt at a Solution [PLAIN][PLAIN]http://img801.imageshack.us/img801/4829/scan0001i.jpg An upload of my attempt to solve the problem. Not sure to interpret the results. A = B...
  36. D

    Solving Wave Equations with Boundary Conditions

    Homework Statement http://img685.imageshack.us/img685/5585/63862334.png Homework Equations -The Attempt at a Solution y_1(0,t)=y_2(0,t) \longrightarrow 1+\frac{B}{A}e^{2i \omega t} = \frac{C}{A} y_1_x(0,t)=y_2_x(0,t) \longrightarrow 1+\frac{B}{A}e^{2i \omega t} =\frac{k_2}{k_1}...
  37. N

    Sturm-Liouville Like Equation with Boundary Conditions on Second Derivative

    Hello, I am facing a diffusion equation.. \frac{du(x,t)}{dt} = D \frac{d^2u}{dx^2} .. with slightly exotic boundary conditions: u(0,t) = 0 \frac{d^2u(a,t)}{dx^2}+ \alpha \frac{du(a,t)}{dx} = 0 I expected the solution to be relatively easy to find, since separation of variables quickly...
  38. T

    Conditions of dot product

    Homework Statement Under what conditions are the following true? a) |\mathbf{a}\cdot \mathbf{b}| =|\mathbf{a}||\mathbf{b}| b) (\mathbf{a} + \mathbf{b}) \cdot (\mathbf{a} - \mathbf{b}) = |\mathbf{a}|^2 - |\mathbf{b}|^2 Homework Equations None. The Attempt at a Solution a) I...
  39. A

    Gravitational Conditions: Dust Cloud vs Black Hole

    I am sure to those of you who know GR this will be a simplistic question. I can only hope there will be a simplistic and definitive answer :-) Assume a dust cloud of radius=5 and a mass =mc ANother equivalent mass of condenced matter md=mc with a radius=1 What would be the...
  40. R

    Finding voltages across capacitors under DC conditions

    Homework Statement Find the voltage across the capacitors in the circuit given under DC conditions.Homework Equations V=IRThe Attempt at a Solution The solution is already given (the picture attached was obtained from the solution manual. I have a difficult time understanding how they arrived...
  41. B

    Linear Algebra determine the conditions

    Homework Statement determine the conditions on a b c and d such that the matrix a b c d will be row equivalent to the given matrix: 1 0 0 1 and 1 0 0 0 Homework Equations The Attempt at a Solution I have no idea what its asking, I mean on no. 1: a = 1 b = 0 c...
  42. O

    Differential Equation with Boundary Conditions II

    Homework Statement d^2T/dx^2 + S^2*T+B=0 Boundary Conditions: dT/dx=0 @ x=0 T=T_2 @ x=L Homework Equations The Attempt at a Solution I think you either have to make some type of substitution or find the roots and do it that way. P.S. This is assignment is a review of diff...
  43. O

    Differential equuation with boundary conditions

    Homework Statement d^2T/dx^2+S/K=0 Boundary Conditions T=Tsub1 @ x=0 and T=Tsub2 @ x=L Homework Equations The Attempt at a Solution d^2T/dx^2 = -(S/K) <--- intergrate to get dT=-(S/K)dx+ C1 <--- intergrate to get T=(-S/K)x+c1+c2 apply both boundary conditions to get...
  44. D

    How to deal with this Neumann boundary conditions?

    hi all, I am trying to solve this PDE by separation of variables, it goes like this: \frac{\partial u}{\partial t} = \alpha\frac{\partial ^2 u}{\partial z^2} for 0\leq z\leq infty the initial condition I have is: t=0; u = uo. the boundary condtions: z=0; \frac{\partial...
  45. W

    Magnetostatic field: solution to Poisson's equation and Boundary Conditions

    How to derive boundary conditions for interfaces between ferromagnetic material and air? Please see the attached figure. Any hints will be greatly appreciated!
  46. H

    Is the topological insulators a result of boundary conditions with SO coupling ?

    Hi, these days I have been trying to understand the essentials of the so-called topological insulators (TBI), such as Bi2Te3, which seem very hot in current research. As i understand, these materials should possesses at the same time gapped bulk bands but gapless surface bands, and spin-orbit...
  47. E

    Rate of change of pressure with volume, adiabatic vs isothermal conditions

    Homework Statement For a particular sample of monatomic gas, the rate of change of pressure with volume under isothermal conditions is -2 x 10^7 Pa m^-3. Calculate the rate of change under adiabatic conditions. Homework Equations isothermal: dP/dV = -2 x 10^7 Q = nRTln(Vf/Vi)...
  48. T

    NDSolve Quirkiness - Updating the initial conditions after each step?

    I'm modeling a physical system described by a second-order ODE with LOTS of parameters. Using SciLab, I sucessfully implimented the model using a while loop with time. Because of the loop structure, every time I called the DE solver (ode), I updated the intial conditions for the current...
  49. C

    Maxwell equations with time-dependent boundary conditions

    Hi folks, I was wondering how to code a Maxwell solver for a problem with time-dependent boundary conditions. This is not my homework, but I love programming and would like to implement what I learned in my physics undergrad course to get a better understanding. More precisely, if I have an...
Back
Top