What is Lorentz: Definition and 1000 Discussions

Lorentz is a name derived from the Roman surname, Laurentius, which means "from Laurentum". It is the German form of Laurence. Notable people with the name include:

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  1. L

    A Lorentz Transformations: Why We Need the Same $\gamma$

    If we have motion of system ##S'## relative to system ##S## in direction of ##x,x'## axes, Lorentz transformation suppose that observers in the two system measure different times ##t## and ##t'##. x'=\gamma(x-ut) x=\gamma(x'+ut') Why we need to use the same ##\gamma## in both relations? Why not...
  2. jk22

    I Does Bell's theorem imply other Lorentz transformations?

    Could it be that the transformations keeping the wave equation invariant have other solutions than the usual Lorentz ones ?
  3. jk22

    B Is Bell's inequality Lorentz invariant?

    I browsed the net and found : https://arxiv.org/abs/quant-ph/0408127 It is said the value of Bell's operator depends on the speed, so how can it be Lorentz invariant ?
  4. A

    B Question About Lorentz Contraction: Red vs Blue?

    I have a question which I've found very difficult to Google. The easiest way to frame it I can think of is this: Given a cylinder moving lengthwise by an observer at some significant fraction of C, with the forward half of the cylinder (relative to the direction of motion) painted red, and the...
  5. Y

    Deriving commutator of operators in Lorentz algebra

    Li=1/2*∈ijkJjk, Ki=J0i,where J satisfy the Lorentz commutation relation. [Li,Lj]=i/4*∈iab∈jcd(gbcJad-gacJbd-gbdJac+gadJbc) How can I obtain [Li,Lj]=i∈ijkLk from it?
  6. bos3yed651

    I Exploring Special Relativity: A Pickle in Lorentz Theory

    This is my first thread. I hope I do it right. I just started reading the book Special Relativity by W.Rindler. And as I was reading it, I stumbled upon a pickle. So in Lorentz theory, it says, supposedly we could measure the original to-and-fro time T2 directly with a clock, and suppose we...
  7. Q

    Checking the Lorentz transformation

    Homework Statement: This seemed at first glance very easy. But there appeared some confusion. A is moving to the right with velocity v with respect to B. The proper time for A is ##t_a=t_b\sqrt{1-v^2/c^2}##. And B is moving to the right with velocity u with respect to C. Proper time for B...
  8. T

    Invariance of the Lorentz transform

    of course y and z terms are invariant but for the x and t terms I am getting an additional factor of 1/1-v^2/c^2
  9. Athenian

    [Special Relativity] Lorentz Transformation and Boosts

    [BEGINNGING NOTICE] Before I begin showing my attempted solution, I would just like to quickly mention that this is a "repost" of the same question I had around a week ago. While I would usually use the "reply" function on the same thread, I believe that thread is getting pretty messy (sometimes...
  10. U

    Generalized Lorentz Transformation

    Summary: The problem is to generalize the Lorentz transformation to two dimensions. Relevant Equations Lorentz Transformation along the positive x-axis: $$ \begin{pmatrix} \bar{x^0} \\ \bar{x^1} \\ \bar{x^2} \\ \bar{x^3} \\ \end{pmatrix} = \begin{pmatrix} \gamma & -\gamma \beta & 0 & 0 \\...
  11. M

    Special Relativity question using Lorentz Transformation time dilation

    with distance between planets as 4x10^8m measured by you on the ship My attempt: t' = γ(t - ux/c^2) γ = 5/3 u = 0.8c t = 0.9s x = 4x10^8m answer is: -0.278 Therefore not possible My question is what if we traveled rightwards, from p2 to p1, would the answer change? Should my above information...
  12. Athenian

    [University Special Relativity] Lorentz Transformation and Boosts

    Unfortunately, I am not entirely confident of the above equations being able to do the trick and ultimately solve for the question. However, my guess is that using the equation written above for "boost", I could perhaps use ##v## and insert it into the ##x##-direction part of the matrix...
  13. R

    How Can the Lorentz Force Be Used to Solve the Magnetic Mirror Problem?

    a) I know the invariants are $\mu = \frac{0.5*m*v_{perp}^2{B} $ and $J = v_{parallel} x b) I used the invariance of $\mu$ to get the following equation: $$ v_{perp}^2 = v_{perp,0}^2(1+\alpha(t)^2 z^2) $$ I am thinking of using the Lorentz force to get $v_z$, but I'm not so clear on how to go...
  14. jk22

    A Lorentz Transformation: Wave Equation vs. Interval Invariance

    To find the Lorentz transformation, should it start with the invariance of the wave-equation ? If so, then it gives 5 equations, 2 of them being wave-equations again. If however the invariance of the space-time interval is demanded only 3 quadratic equations come out. Which way should be...
  15. A

    Lorentz transformation of 4-acceleration

    I have been getting back to studying physics after a long break and decided to go through the problems in Rindler. But there is something I don't quite understand in this problem. To first answer the second part, Exercise II(12), I wrote $$\frac{du_2}{dt} = \frac{du_2}{du_2^\prime}...
  16. ?

    I How specifically does an accelerated uniform rod Lorentz contract?

    I am trying to push the boundaries of special relativity with a self-imposed challenge problem. A common derivation of relativistic kinetic energy involves an object to which a constant force is applied. I want to consider a similar scenario, but instead of a point object we now have a uniform...
  17. Luke Tan

    B Landau's Derivation of Lorentz Transformations: Questions Answered

    In his book, Landau derives the Lorentz transformations using the invariance of the interval, and I have some questions about it that I would like to clarify 1. What is a parallel displacement of a coordinate system? Does it refer to moving along any axis? I don't see how any arbitrary...
  18. Demystifier

    I Special relativity vs Lorentz invariance

    The Lorentz covariance of Maxwell equations was known before Einstein formulated special relativity. So what exactly special relativity brought new with respect to mere Lorentz covariance? Is special relativity just an interpretation of Lorentz invariance, in a sense in which Copenhagen...
  19. chaksome

    I Lorentz transformation for 3 frames (2 dimensions)

    I want to know why an else solution can not get the right answer. And want to know the way to correct this solution.Supposed that a frame S'' is moving in the lab frame at ##\beta_x## in the x-direction, ##\beta_y## in the y-direction, now I want to find out the Lorentz transformation between...
  20. Jason Bennett

    Lorentz algebra elements in an operator representation

    1) Likely an Einstein summation confusion. Consider Lorentz transformation's defined in the following matter: Please see image [2] below. I aim to consider the product L^0{}_0(\Lambda_1\Lambda_2). Consider the following notation L^\mu{}_\nu(\Lambda_i) = L_i{}^\mu{}_\nu. How then, does...
  21. Jason Bennett

    Lie groups,Lie algebras, Physics, Lorentz Group,

    1) How do we determine a Lie group's global properties when the manifold that it represents is not immediately obvious? Allow me to give the definitions I am working with. A Lie group G is connected iff \forall g_1, g_2 \in G there exists a continuous curve connecting the two, i.e. there...
  22. Aagno3

    Lorentz Forces: All the Details You Need to Know!

    Hey y'all Can anyone just tell me every detail about Lorentz forces ? I have a pretty good idea, but i want to surprise everyone in the presentation that i am about to give, so please just tell me whatever detail you know . Every single detail might be helpful . Also , if anyone knows how to...
  23. Universeer

    Lorentz force between two moving charges

    Two charges are moving mutually perpendicular to each other in space with constant velocities. The moment one charge crosses over the line of path of second charge the force on 1st charge (located just behind the 2nd charge moving away from it) appear to be zero (Magnetic field due to 2nd...
  24. arnau

    I Lorentz transformation for 3 frames

    A particle is moving in the lab frame ##S'## at ##\beta'_z##. I want to transform coordinates and momenta of the particle to a frame ##S## moving at ##\beta_0##. At time ##t = t' = 0##: $$z = \frac{z'} { \gamma_0 (1 - \beta'_z \beta_0) },\, \gamma\beta_z = \gamma_0 ( \gamma'\beta'_z -...
  25. D

    I Lorentz transformation of derivative and vector field

    I'm currently watching lecture videos on QFT by David Tong. He is going over lorentz invariance and classical field theory. In his lecture notes he has, $$(\partial_\mu\phi)(x) \rightarrow (\Lambda^{-1})^\nu_\mu(\partial_\nu \phi)(y)$$, where ##y = \Lambda^{-1}x##. He mentions he uses active...
  26. E

    A Applying General Lorentz Boost to Multipartite Quantum State

    I would like to apply a General Lorentz Boost to some Multi-partite Quantum State. I have read several papers (like this) on the theory of boosting quantum states, but I have a hard time applying this theory to concrete examples. Let us take a ##|\Phi^+\rangle## Bell State as an example, and...
  27. jk22

    I Lorentz Boost & Galileo Speed: Exploring Relationship

    What about if the speed parameter in a Lorentz boost were in fact related nontrivially to a Galilean speed ? More formally ##L(v_L)=G(v)\circ F## where L is a Lorentz boost with Lorentz speed ##v_L##, G is a Galileo transformation with speed ##v## and ##F## is still an unknown linear...
  28. N

    Conserved quantities under the Lorentz boost

    In physics, a symmetry of the physical system is always associated with some conserved quantity. That physical laws are invariant under the observer’s displacement in position leads to conservation of momentum. Invariance under rotation leads to conservation of angular momentum, and under...
  29. E

    B Difficulty with derivatives using the Lorentz transformations

    Two frames measure the position of a particle as a function of time: S in terms of x and t and S', moving at constant speed v, in terms of x' and t'. The acceleration as measured in frame S is $$ \frac{d^{2}x}{dt^{2}} $$ and that measured in frame S' is $$ \frac{d^{2}x'}{dt'^{2}} $$My question...
  30. K

    I Lorentz Transformations: Linearity & Best Argument

    There are several ways to show that the Lorentz transformations must be linear. What's the best/more intuitive argument in your opinion?
  31. filip97

    A (A,A) representation of Lorentz group-why is it tensor?

    Why representation of Lorentz group of shape (A,A) corespond to totally symmetric traceless tensor of rank 2A? For example (5,5)=9+7+5+3+1 (where + is dirrect sum), but 1+5+3+9+7<>(5,5) implies that (5,5) isn't symmetric ? See Weinberg QFT Book Vol.1 page 231.
  32. jk22

    B Deriving Lorentz Transformation: Wave Eq Invariance & General Relativity

    I read the Lorentz transformation can be obtained by solving the requirement of invariance of the wave equation. If one considers linear transformations this the same as the spacetime interval squared to be invariant. What are the other nonlinear transformations keeping the wave equation...
  33. P

    Why is the Lorentz force linear with velocity?

    I am working on derivation of Lorentz force. (I know that Lorentz force is in some sense definition of fields, but still there is nontrivial dependence on velocity). I want to derive that the force is linear in components of velocity, so for example $$F_x=q(E+Av_x + Bv_y + Cv_z ),$$where ##A...
  34. B

    Deriving Lorentz Transformations for Moving Reference Frames

    Problem Statement: Consider three frames Σ (x, y, z, t), Σ' (x', y', z', t'), and Σ'' (x'', y'', z'', t'') whose x, y, and z axes are parallel at each point in time stay. Σ' moves relative to Σ with velocity v1 along the x-axis. The system Σ'' moves relative to Σ' with the velocity v2 along the...
  35. T

    A Showing Delta^3(p-q) is Not Lorentz Invariant

    From page 22 of P&S we want to show that ##\delta^{3}(\vec{p}-\vec{q})## is not Lorentz invariant. Boosting in the 3-direction gives ##p_{3}' = \gamma(p_{3}+\beta E)## and ##E' = \gamma(E+\beta p_{3})##. Using the delta function identity ##\delta(f(x)-f(x_{0})) =...
  36. L

    I Why 3-momenta + lorentz invariance = large energy?

    Why is that when there is lorentz invariance. Large 3-momentum corresponds to a large energy. And if there was no lorentz invariance. Large 3-momentum does not necessarily need to correspond to a large energy? What has Lorentz invariance got to do with 3-momentum having large energy or not?
  37. berlinspeed

    B Why Does Proper Time in Lorentz Geometry Use t²-x² Instead of t²+x²?

    Can someone tell me why the proper time between αβ is not t2+x2 but rather t2-x2? Background:
  38. K

    I Derivation of the Lorentz transformations

    It seems that there is a considerable number of ways of deriving the Lorentz transformations. Does anyone know how many ways are there?
  39. S

    I General Lorentz Transformation Explained: Visualize and Grasp It!

    Hi guys, I'm reading a book 'the theoretical minimum: special relativity and classical field theory'. In chapter 1.3, author explains the general Lorentz transformation. He said "Suppose you have two frames in relative motion along some oblique direction, not along any of the coordinate axes...
  40. JMart12

    I Solving the HUGE Issue with Lorentz Transformations and Lightning Strikes

    In the Earth’s reference frame, a tree is at x=0km and a pole is at x=20km. A person stands at x=0 (stationary relative to the Earth), and at t=10 microseconds, this person witnesses two simultaneous lightning strikes. One of these strikes hits the tree he is standing under, and the other hits...
  41. K

    How does the retarded scalar potential satisfy the Lorentz gauge condition?

    As homework, I shall show that the retarded scalar potential satisfîes the Lorentz gauge condition as well as the inhomogenous wave equation. We saw in class how to do it. But I was thinking about this, and it seems to me that it's redundant to prove both of those things. For, if the scalar...
  42. G

    A How does Lorentz invariance help evaluate tensor integrals?

    We're trying to reduce the tensor integral ##\int {\frac{{{d^4}k}}{{{{\left( {2\pi } \right)}^4}}}} \frac{{{k^\mu }{k^\nu }}}{{{{\left( {{k^2} - {\Delta ^2}} \right)}^n}}}{\rm{ }}## to a scalar integral (where ##{{\Delta ^2}}## is a scalar). We're told that the tensor integral is proportional...
  43. P

    Why Does t' Include vx/c² in Lorentz Transformations?

    I understand x' = λ(x - vt) but why does t' = λ(t - vx/c^2)? where does the vx/c^2 come from? and honestly I don't understand what t' is. because from what I understand is that t' is the length of time t as observed from the reference frame S'. which means t' = t*λ?
  44. TobilobaEinstein

    B Deriving the Lorentz transformations

    I have tried to derive the lorentz transformations but there is a part of it that requires substitution into two equations when t=0. How do I do that
  45. N

    B Understanding Final Form of Lorentz Transformations

    In my last post I asked about the general form of the Lorentz Transformation for time. Now I am trying to understand the final form of it, and how it makes sense based on what's happening physically. The final form for t is: t = γt1 + (γv/c2/)x1 It's the second part of this equation, the...
  46. Pencilvester

    I Lorentz Transformation Derivation: Assumptions Req'd?

    In deriving the Lorentz transformation, is it required to assume that the transformation to get from coordinate system ##\bf {x}## to ##\bf {x’}## should be the same as that to get from ##\bf {x’}## to ##\bf {x}## (with the simple correction of flipping the velocity)? If no, could someone...
  47. Wein_Sim

    Reaction Force of Lorentz Force

    Hi everyone, in school we recently learned about the Lorentz Force, which says that when charged particles move through an electric field (perpendicular to the field lines), a force is excerted on them (called the Lorentz Force), which goes perpendicular to both the magnetic field lines and the...
  48. S

    Detecting Lorentz Force: Experiment with Strong Neodymium Magnet

    I setup an experiment to detect a magnetic field due to the Lorentz force acting on a current. It is a hollow conducting cylinder with a magnet at one end. With current flowing in the cylinder I approach the negative end with the north pole of the magnet. Using the left hand rule I expected the...
  49. M

    Proving commutation relation

    Homework Statement Prove that the sets ##(S_{\mu\nu})_L## and ##(S_{kl})_R##, where $$ \left( S _ { k \ell } \right) _ { L } = \frac { 1 } { 2 } \varepsilon _ { j k \ell } \sigma _ { j } = \left( S _ { k \ell } \right) _ { R } \quad\text{and}\quad \left( S _ { 0 k } \right) _ { L } = \frac {...
  50. N

    B Trying to understand Lorentz Transformations

    I am trying to understand the general form of the Lorentz Transformations before I even get into the long process of deriving that into the specific equations. In Taylor and Wheeler's, Spacetime Physics book they give this as the general form: t= Bx1 + Dt1 x= Gx1 + Ht1 In the equation for t...
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