I Relativistic hidden variable quantum mechanics?

  • #51
PeterDonis said:
So what in your model prevents a classical apparatus from following a spacelike trajectory, if the individual Bohmian particles can?
A classical apparatus is a macroscopic object, the trajectory of which is defined by the motion of the non-empty wave packet. See Fig. 2 in https://arxiv.org/abs/1309.0400 for an idea how macroscopic trajectory may look very different from the microscopic one.
 
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  • #52
A. Neumaier said:
But then the problem of how to motivate and explain the Lagrangian of QED, QCD and the standard model, which are all based on Lorentz invariance, becomes even more pressing. Just assuming that there is a miraculous way these appear by coarse graining from some unspecified and unknown noninvariant theory requires a lot of faith, and few would follow your faith.
"The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man."
- George Bernard Shaw
 
  • #53
Demystifier said:
"The reasonable man adapts himself to the world; the unreasonable one persists in trying to adapt the world to himself. Therefore all progress depends on the unreasonable man."
- George Bernard Shaw
Well, Shaw didn't achieve anything in physics. Progress in physics depends on finding something adapted both to the world and to one's vision! This characterized the work of Planck, Einstein, Heisenberg, Dirac, Feynman ...
 
  • #54
martinbn said:
Well, let's say equation ##(94)## or if you prefer ##(99-100)## with the equations for the particles ##(117)##. How do you set up the IVP?
One first writes down the general solution of (94), parametrized by an infinite number of free constants. Then one picks a particular solution by picking some specific values of those constants. In this way (94) is solved without choosing an initial value. Finally, one solves (117) by an initial condition at, say, ##s=0##.
 
  • #55
A. Neumaier said:
Well, Shaw didn't achieve anything in physics. Progress in physics depends on finding something adapted both to the world and to one's vision! This characterized the work of Planck, Einstein, Heisenberg, Dirac, Feynman ...
How about string theorists like Maldacena, Witten, etc? Would you say that they achieved something in physics?
 
  • #56
martinbn said:
Can the writer supply the proof?
He can, which doesn't mean that he will. :-p
You have to be a better motivator. You have to say something like "Wow, you explained that so well, it would be great if you could just fill this little detail, so that my understanding of your great ideas can be complete." :biggrin:

But I am in a good mood these days, so I will give you a sketch of the proof for ##n=1##. Suppose that ##V^{\mu}V_{\mu}=0##, but ##V^{\mu}\neq 0## and ##V^{\mu}\neq \infty##. Then
$$\frac{dX^{\mu}}{ds}=V^{\mu}\neq 0, \infty \;\;\;\; (1)$$
Therefore on a line segment on which ##dX^{\mu}\neq 0## we have ##dX^{\mu}dX_{\mu}=0##, but (1) implies that ##ds\neq 0##. ##\Box##

If you don't accept a proof using infinitesimals, I live it to you to reformulate this in the ##\epsilon##-##\delta## language or in an integral form.
 
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  • #57
Demystifier said:
How about string theorists like Maldacena, Witten, etc? Would you say that they achieved something in physics?
The future will tell about the contribution of string theory to physics.

But Witten also contributed to ordinary QFT and to pure mathematics. In mathematics he obtained the fields medal, at the time the highest distinction.
 
  • #58
A. Neumaier said:
The future will tell about the contribution of string theory to physics.
Likewise the future will tell whether Lorentz invariance is only emergent at a coarse grained level.
 
  • #59
Demystifier said:
Likewise the future will tell whether Lorentz invariance is only emergent at a coarse grained level.
But we are discussing the present state of affairs.
 
  • #60
Demystifier said:
One first writes down the general solution of (94), parametrized by an infinite number of free constants. Then one picks a particular solution by picking some specific values of those constants. In this way (94) is solved without choosing an initial value. Finally, one solves (117) by an initial condition at, say, ##s=0##.
It is still not clear to me. What do you mean by the general solution with infinite number of constants? And how do you pick their values? What information is given?

Here is a simple example. Take the usual wave equation in ##1+1## dimensions. It has a general solution ##u(x,t)=f(x-ct)+g(x+ct)## for arbitrary functions ##f## and ##g##. How do you pick your solution? And what happens in higher dimensions, what is the general solution?
 
  • #61
A. Neumaier said:
But we are discussing the present state of affairs.
You are the one who first mentioned future in relation to the value of string theory.
 
  • #62
Demystifier said:
You are the one who first mentioned future in relation to the value of string theory.
Only because you asked a question unrelated to the thread.
 
  • #63
Demystifier said:
He can, which doesn't mean that he will. :-p
You have to be a better motivator. You have to say something like "Wow, you explained that so well, it would be great if you could just fill this little detail, so that my understanding of your great ideas can be complete." :biggrin:

But I am in a good mood these days, so I will give you a sketch of the proof for ##n=1##. Suppose that ##V^{\mu}V_{\mu}=0##, but ##V^{\mu}\neq 0## and ##V^{\mu}\neq \infty##. Then
$$\frac{dX^{\mu}}{ds}=V^{\mu}\neq 0, \infty \;\;\;\; (1)$$
Therefore on a line segment on which ##dX^{\mu}\neq 0## we have ##dX^{\mu}dX_{\mu}=0##, but (1) implies that ##ds\neq 0##. ##\Box##

If you don't accept a proof using infinitesimals, I live it to you to reformulate this in the ##\epsilon##-##\delta## language or in an integral form.
Well, it doesn't imply ##ds\neq 0##, it implies ##ds=\frac00##.

But you are just assuming something about the world line. The claim is that the dynamics imply that the ##(something)## has the correct sign or order of vanishing. I don't see even a hint of that, let alone a sketch of proof.
 
  • #64
martinbn said:
It is still not clear to me. What do you mean by the general solution with infinite number of constants? And how do you pick their values? What information is given?

Here is a simple example. Take the usual wave equation in ##1+1## dimensions. It has a general solution ##u(x,t)=f(x-ct)+g(x+ct)## for arbitrary functions ##f## and ##g##. How do you pick your solution? And what happens in higher dimensions, what is the general solution?
Now you ask me questions about standard theory of partial differential equations. I think it's not directly relevant to my relativistic hidden variable theory.
 
  • #65
Demystifier said:
Now you ask me questions about standard theory of partial differential equations. I think it's not directly relevant to my relativistic hidden variable theory.
Ok, answer the same question for equations ##(94)##. What is the general solution and how do you pick the constants? What information is given so that you can determine those constants.
 
  • #66
martinbn said:
Well, it doesn't imply ##ds\neq 0##, it implies ##ds=\frac00##.
Sorry, but you are wrong.
 
  • #67
martinbn said:
Ok, answer the same question for equations ##(94)##. What is the general solution and how do you pick the constants? What information is given so that you can determine those constants.
Let me first make one thing clear. Do you ask because you want to learn something, or do you ask because you want to find my error? I have the feeling that you only want the latter, so you ask nitpicking questions, which are actually easy to me, but I find them pretty much irrelevant.
 
  • #68
Demystifier said:
Sorry, but you are wrong.
Don't you have ##V^{\mu}V_{\mu}## in the denominator?
 
  • #69
Demystifier said:
Let me first make one thing clear. Do you ask because you want to learn something, or do you ask because you want to find my error? I have the feeling that you only want the latter, so you ask nitpicking questions, which are actually easy to me, but I find them pretty much irrelevant.
I don't know if you have an error. I just want to understand the statements, because they make no sense to me. But you don't have to waste time with this, it isn't important.
 
  • #70
martinbn said:
Don't you have ##V^{\mu}V_{\mu}## in the denominator?
From equation (1) above one has (no sum over ##\mu##)
$$ds=\frac{dX^{\mu}}{V^{\mu}}=\frac{non zero}{non zero}$$
 
  • #71
martinbn said:
I just want to understand the statements, because they make no sense to me.
Do statements of ordinary non-relativistic Bohmian mechanics make sense to you? The paper is written with an assumption that the reader is already familiar with non-relativistic Bohmian mechanics, as well as with standard relativistic QM and standard QFT.
 
  • #72
A. Neumaier said:
Only because you asked a question unrelated to the thread.
Then let me put it this way. If string theory is unphysical today, then so is my theory.
 
  • #73
Demystifier said:
From equation (1) above one has (no sum over ##\mu##)
$$ds=\frac{dX^{\mu}}{V^{\mu}}=\frac{non zero}{non zero}$$
You are using ##s## in a confusing way (for two things). Let's say ##X^{\mu}=(\lambda,\lambda,0,0)##. Then ##V^{\mu}=(1,1,0,0)##, and ##V^\mu V_\mu=0##, and ##V^0\neq 0, \infty##. What is ##ds##?
 
  • #74
martinbn said:
You are using ##s## in a confusing way (for two things). Let's say ##X^{\mu}=(\lambda,\lambda,0,0)##. Then ##V^{\mu}=(1,1,0,0)##, and ##V^\mu V_\mu=0##, and ##V^0\neq 0, \infty##. What is ##ds##?
##ds=d\lambda##.
 
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  • #75
martinbn said:
You are using ##s## in a confusing way (for two things). Let's say ##X^{\mu}=(\lambda,\lambda,0,0)##. Then ##V^{\mu}=(1,1,0,0)##, and ##V^\mu V_\mu=0##, and ##V^0\neq 0, \infty##. What is ##ds##?
Demystifier said:
##ds=d\lambda##.
Why? Equation ##(108)## says

##
ds^2=\frac1{V^\mu V_\mu}dX^\mu dX_\mu
##

And in the example above both ##V^\mu V_\mu## and ##dX^\mu dX_\mu## are zero.
 
  • #76
martinbn said:
Why? Equation ##(108)## says

##
ds^2=\frac1{V^\mu V_\mu}dX^\mu dX_\mu
##

And in the example above both ##V^\mu V_\mu## and ##dX^\mu dX_\mu## are zero.
Sec. 5.3 contains a detailed answer to your question.

See also the last paragraph in Sec. 5.2, which answers one of your previous questions.
 
  • #77
Demystifier said:
Sec. 5.3 contains a detailed answer to your question.
It doesn't. To go from ##(114)## to ##(115)## you are either assuming that ##V^\mu V_\mu## and ##dX^\mu dX_\mu## are not zero, or you use division by zero.
Demystifier said:
See also the last paragraph in Sec. 5.2, which answers one of your previous questions.
Not sure which question this answers.
 
  • #78
martinbn said:
It doesn't. To go from ##(114)## to ##(115)## you are either assuming that ##V^\mu V_\mu## and ##dX^\mu dX_\mu## are not zero, or you use division by zero.
You can look at it this way. Eq. (116) is derived for any value of ##V^\mu V_\mu##, except for ##V^\mu V_\mu=0## in which case there is an ambiguity. Therefore it is natural to resolve the ambiguity by postulating (116) to be valid even in this case. Technically it should need a separate postulate, but to me it seemed too obvious to state it explicitly in the paper. (As you know, physicists and mathematicians have very different standards of "obvious".)

See also Eq. (55). Would you say that Newton time ##t## is not well defined when the 3-velocity of a particle is zero?

martinbn said:
Not sure which question this answers.
I think previously you objected that my theory is not really relativistic, or something like that.
 
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  • #79
Demystifier said:
Then let me put it this way. If string theory is unphysical today, then so is my theory.
And if string theory is physical (.i.e., describes reality) today then your theory is unphysical since string theory assumes even more symmetry than Lorentz invariance, while you reject it.

Together with what you just conceded, it follows that your theory is always unphysical!
 
  • #80
A. Neumaier said:
And if string theory is physical (.i.e., describes reality) today then your theory is unphysical since string theory assumes even more symmetry than Lorentz invariance, while you reject it.

Together with what you just conceded, it follows that your theory is always unphysical!
You made two logical errors in arriving to that conclusion. First, you used two different meanings of "physical". Second, you forgot to consider a logical possibility that my theory describes reality, in which case string theory doesn't.
 
  • #81
Demystifier said:
You made two logical errors in arriving to that conclusion. First, you used two different meanings of "physical". Second, you forgot to consider a logical possibility that my theory describes reality, in which case string theory doesn't.
First - we hadn't discussed the definition of physical; for me, physical only means corresponding to reality.

Second - This is your error, not mine. I concluded logically correctly from what you conceded. Indeed, this already excludes the logical possibility you mentioned since the latter implies that string theory is unphysical, so by your previous mail, your theory is unphysical.
 
  • #82
A. Neumaier said:
physical only means corresponding to reality.
Then my theory is ugly, intuitive and possibly physical. :-p
 
  • #83
martinbn said:
It doesn't. To go from ##(114)## to ##(115)## you are either assuming that ##V^\mu V_\mu## and ##dX^\mu dX_\mu## are not zero, or you use division by zero.
How about the following proof? We start from
$$ds^2=\frac{dX^{\mu}dX_{\mu}}{V^{\nu}V_{\nu}}$$
Using
$$\frac{dX^{\mu}}{d\lambda}=V^{\mu}$$
this can be written as
$$ds^2=\frac{V^{\mu}d\lambda V_{\mu}d\lambda}{V^{\nu}V_{\nu}}=\frac{V^{\mu}V_{\mu}}{V^{\nu}V_{\nu}}d\lambda^2
=d\lambda^2$$
so
$$ds=d\lambda$$
Do you think this proof is valid in the limit ##V^{\mu}V_{\mu}\rightarrow 0##? I think it is, because clearly
$$\lim_{V^{\mu}V_{\mu}\rightarrow 0} \frac{V^{\mu}V_{\mu}}{V^{\nu}V_{\nu}}=1$$

If you think it's invalid, do you think that you can do it better?
 
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  • #84
I had a teacher who was involved with these ideas. He wrote some papers in this respect that I found interesting. So, I share here for possible reference.

a) L. C. Ryff, Phys. Rev. A 60, 5083 (1999)
<Moderator's note: links to unpublished results removed.>
 
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  • #85
Demystifier said:
How about the following proof?

Can you explain this in a bit more detail for a dumb ass like me? As far as I can see its not really saying anything - its true - but more like a tautology with no actual content. What am I missing??

Thanks
Bill
 
  • #86
bhobba said:
Can you explain this in a bit more detail for a dumb ass like me? As far as I can see its not really saying anything - its true - but more like a tautology with no actual content. What am I missing??
It shows that quantum proper time ##s## defined by the first equation is non-zero even along null-curves, along which the classical proper time is zero. @martinbn did not believe that it can be so, so I had to show him that explicitly. If this proof looks like a tautology, that probably means that proof is convincing. But the main idea of the proof is to write it in such a form that one can apply it even to the null-curves, i.e. in the limit ##V^{\mu}V_{\mu}\rightarrow 0##. Without that limit, the proof is indeed quite trivial. The fact that @martinbn had no further comments also indicates that proof is convincing.
 
  • #87
Demystifier said:
$$ds^2=\frac{dX^{\mu}dX_{\mu}}{V^{\nu}V_{\nu}}$$
This expression is nonsensical in the first place. It neither specifies a proper metric, since the coefficients of the ##\mathrm d X^\mu## aren't functions of spacetime, nor a proper line element, because it doesn't define a reparametrization invariant length integral. Only Einstein's expression has this property. If I asked you to calculate the length of a circle with this formula, you couldn't do it, because you'd need me to specify additional unphysical information. The same circle would have have different length, depending on whether I parametrize it as ##(\cos(\lambda),\sin(\lambda),0,0)## or as ##(\cos(\lambda^2),\sin(\lambda^2),0,0)##.
 
  • #88
rubi said:
This expression is nonsensical in the first place. It neither specifies a proper metric, since the coefficients of the ##\mathrm d X^\mu## aren't functions of spacetime, nor a proper line element, because it doesn't define a reparametrization invariant length integral. Only Einstein's expression has this property. If I asked you to calculate the length of a circle with this formula, you couldn't do it, because you'd need me to specify additional unphysical information. The same circle would have have different length, depending on whether I parametrize it as ##(\cos(\lambda),\sin(\lambda),0,0)## or as ##(\cos(\lambda^2),\sin(\lambda^2),0,0)##.
I disagree. Just as classical proper time depends on the classical dynamical quantity ##g_{\mu\nu}## which itself is found by solving classical (Einstein) equations, this quantum proper time depends on the quantum dynamical quantity ##V^{\mu}## which itself is found by solving quantum (e.g. Klein Gordon or Dirac) equations. As shown in the paper, this quantum proper time does not depend on the parametrization.
 
  • #89
The standard expression for the length integral of a curve ##x : [0,1] \rightarrow \mathbb R^4## is:
##\int_\gamma \mathrm d s = \int_0^1 \sqrt{g_{\mu\nu}(x(\lambda))\frac{\mathrm d x^\mu(\lambda)}{\mathrm d\lambda}\frac{\mathrm d x^\nu(\lambda)}{\mathrm d\lambda}}\,\mathrm d\lambda##
Now, if we reparametrize ##x(\lambda) \rightarrow x(f(\lambda))## (with ##f(0)=0## and ##f(1)=1##), we can evaluate the integral again with the new parametrization:
##\int_0^1 \sqrt{g_{\mu\nu}(x(f(\lambda)))\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d\lambda}\frac{\mathrm d x^\nu(f(\lambda))}{\mathrm d\lambda}}\,\mathrm d\lambda = \int_0^1 \sqrt{g_{\mu\nu}(x(f(\lambda)))\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d f(\lambda)}\frac{\mathrm d f(\lambda)}{\mathrm d\lambda}\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d f(\lambda)}\frac{\mathrm d f(\lambda)}{\mathrm d\lambda}}\,\mathrm d\lambda = \int_0^1 \sqrt{g_{\mu\nu}(x(f(\lambda)))\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d f(\lambda)}\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d f(\lambda)}}\frac{\mathrm d f(\lambda)}{\mathrm d\lambda}\,\mathrm d\lambda = \int_{f^{-1}(0)}^{f^{-1}(1)} \sqrt{g_{\mu\nu}(x(f))\frac{\mathrm d x^\mu(f)}{\mathrm d f}\frac{\mathrm d x^\mu(f)}{\mathrm d f}}\,\mathrm d f = \int_0^1 \sqrt{g_{\mu\nu}(x(f))\frac{\mathrm d x^\mu(f)}{\mathrm d f}\frac{\mathrm d x^\mu(f)}{\mathrm d f}}\,\mathrm d f = \int_\gamma\mathrm d s##
So the standard length integral is indeed independent of the choice of reparametrization. We used the substitution rule (##\int_0^1 g(f(\lambda)) \frac{\mathrm d f(\lambda)}{\mathrm d\lambda}\,\mathrm d \lambda = \int_{f^{-1}(0)}^{f^{-1}(1)} g(f) \,\mathrm d f##) in the last step. Now if we use your expression instead, the factor ##\frac{\mathrm d f(\lambda)}{\mathrm d \lambda}## will not come out of the square root, because it would cancel with the factor that you will get from transforming the velocities in the denominator and hence, the substitution rule won't apply, rendering the integral dependent of the choice of paramentrization.
 
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  • #90
rubi said:
The standard expression for the length integral is:
##\int_\gamma \mathrm d s = \int_a^b \sqrt{g_{\mu\nu}(x(\lambda))\frac{\mathrm d x^\mu(\lambda)}{\mathrm d\lambda}\frac{\mathrm d x^\nu(\lambda)}{\mathrm d\lambda}}\,\mathrm d\lambda##
Now, if we reparametrize ##x(\lambda) \rightarrow x(f(\lambda))##, we can evaluate the integral again with the new parametrization:
##\int_a^b \sqrt{g_{\mu\nu}(x(f(\lambda)))\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d\lambda}\frac{\mathrm d x^\nu(f(\lambda))}{\mathrm d\lambda}}\,\mathrm d\lambda = \int_a^b \sqrt{g_{\mu\nu}(x(f(\lambda)))\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d f(\lambda)}\frac{\mathrm d f(\lambda)}{\mathrm d\lambda}\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d f(\lambda)}\frac{\mathrm d f(\lambda)}{\mathrm d\lambda}}\,\mathrm d\lambda = \int_a^b \sqrt{g_{\mu\nu}(x(f(\lambda)))\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d f(\lambda)}\frac{\mathrm d x^\mu(f(\lambda))}{\mathrm d f(\lambda)}}\frac{\mathrm d f(\lambda)}{\mathrm d\lambda}\,\mathrm d\lambda = \int_{f^{-1}(a)}^{f^{-1}(b)} \sqrt{g_{\mu\nu}(x(f))\frac{\mathrm d x^\mu(f)}{\mathrm d f}\frac{\mathrm d x^\mu(f)}{\mathrm d f}}\,\mathrm d f = \int_\gamma\mathrm d s##
So the standard length integral is indeed independent of the choice of reparametrization. We used the substitution rule (##\int_a^b g(f(\lambda)) \frac{\mathrm d f(\lambda)}{\mathrm d\lambda}\,\mathrm d \lambda = \int_{f^{-1}(a)}^{f^{-1}(b)} g(f) \,\mathrm d f##) in the last step. Now if we use your expression instead, the factor ##\frac{\mathrm d f(\lambda)}{\mathrm d \lambda}## will not come out of the square root, because it would cancel with the factor that you will get from transforming the velocities in the denominator and hence, the substitution rule won't apply, rendering the integral dependent of the choice of paramentrization.
The velocities are just vector fields, so they don't cancel what you think they do. My length integral is invariant in exactly the same way as the standard length integral in your derivation above, with a replacement ##g_{\mu\nu}(x)\rightarrow G_{\mu\nu}(x)## where
$$G_{\mu\nu}(x)=\frac{g_{\mu\nu}(x)}{g_{\alpha\beta}(x)V^{\alpha}(x)V^{\beta}(x)}$$
You can think of my theory as a geometrical theory with a new effective metric ##G_{\mu\nu}(x)##.
 
  • #91
Demystifier said:
The velocities are just vector fields, so they don't cancel what you think they do. My length integral is invariant in exactly the same way as the standard length integral in your derivation above, with a replacement ##g_{\mu\nu}(x)\rightarrow G_{\mu\nu}(x)## where
$$G_{\mu\nu}(x)=\frac{g_{\mu\nu}(x)}{V_{\alpha}(x)V^{\alpha}(x)}$$
You can think of my theory as a geometrical theory with a new effective metric ##G_{\mu\nu}(x)##.
No I can't. What does ##V^\alpha(x)## even mean? It needs to be ##V^\alpha(\lambda)##. Velocities aren't vector fields. They depend on the parametrization of the curve. If you run through the curve at twice the speed, they are twice as long.
 
  • #92
rubi said:
No I can't. What does ##V^\alpha(x)## even mean? It needs to be ##V^\alpha(\lambda)##. Velocities aren't vector fields. They depend on the parametrization of the curve. If you run through the curve at twice the speed, they are twice as long.
Obviously you didn't read the paper. My velocity is a vector field defined by Eq. (102) in https://arxiv.org/abs/1309.0400
It is similar to the velocity in the classical Hamilton-Jacobi theory in Eq. (23), which is also a vector field. If you claim the opposite, then you don't understand the Hamilton-Jacobi theory.
 
  • #93
In your post #83, you used this definition:
Demystifier said:
$$\frac{dX^{\mu}}{d\lambda}=V^{\mu}$$
So either your post #83 is wrong or your paper is wrong.
 
  • #94
rubi said:
In your post #83, you used this definition:
So either your post #83 is wrong or your paper is wrong.
I never said that it is a definition. It is Eq. (113) in the paper, which is not a definition. Nothing is wrong, you just don't read carefully.
 
  • #95
Demystifier said:
I never said that it is a definition. It is Eq. (113) in the paper, which is not a definition.
In response to my post, you argued that ##V^\mu(x)## does not depend on the parametrization of the curve. The formula ##V^\mu = \frac{\mathrm d X^\mu}{\mathrm d\lambda}## does depend on the parametrization of the curve, independent of whether it is a definition or a derived formula. So it's still true that either your post #83 is wrong or your paper is wrong. (Edit: In fact, your paper is wrong, since as you said, the formula is also in your paper.)
 
  • #96
rubi said:
In response to my post, you argued that ##V^\mu(x)## does not depend on the parametrization of the curve. The formula ##V^\mu = \frac{\mathrm d X^\mu}{\mathrm d\lambda}## does depend on the parametrization of the curve, independent of whether it is a definition or a derived formula. So it's still true that either your post #83 is wrong or your paper is wrong.
Or you just refuse to read carefully. Please read my paper if you want to discuss it, otherwise it doesn't make sense. For a start, you need to distinguish ##V^{\mu}(x)## from ##V^{\mu}(X(\lambda))##.
 
  • #97
Demystifier said:
Or you just refuse to read carefully. Pleas read my paper if you want to discuss it, otherwise it doesn't make sense.
I can already tell that you made a mistake without reading your paper. In post #83 you wrote a formula that definitely depends on the parametrization of the curve and in post #92 you claimed that it doesn't depend on the parametrization of the curve. One of the posts must necessarily be wrong. I don't need to read any paper in order to recognize this contradiction. If you disagree, then surely you are able to explain it here, instead of just claiming that the answer is somewhere to be found in those 53 pages.
 
  • #98
rubi said:
If you disagree, then surely you are able to explain it here, instead of just claiming that the answer is somewhere to be found in those 53 pages.
I will not repeat what I already wrote in the paper. If you don't want to read the whole paper, read only Secs. 5.2 and 5.3. If it is too much for you, then I can't help you.
 
  • #99
Demystifier said:
I will not repeat what I already wrote in the paper. If you don't want to read the whole paper, read only Secs. 5.2 and 5.3. If it is too much for you, then I can't help you.
I have read those sections now and I can only guess that you want me to accept that equation (112) and the paragraph above it show that the cuves somehow become independent of the parametrization. However, this is where your paper is wrong. Equation (112) does not prove that the trajectories don't depend on ##\lambda## or ##\Omega##. It's simply not true. Different choices of ##\Omega## will in fact lead to different parametrizations of the curve.
 
  • #100
rubi said:
Different choices of ##\Omega## will in fact lead to different parametrizations of the curve.
Of course they will, but different parametrizations of the same curve.
 
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