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No, I am just pointing out that you are trolling while posting mistakes. You have been doing it since I started posting in this thread.

He's comparing free-falling frames with the Earth-bound frame. You seem to have a serious reading comprehension.

I would recommend a chapter of GR ("Photon Trajectories" or "Light Bending by Gravitating Bodies") that deals with these issues but I know by now that it is futile. You have no intention to study anything, you are just spraying the forums with questions, only to ignore the answers. You will never do any calculation. You keep trying to compare accelerated frames results with inertial frame results. Physics doesn't work this way. This is the fourth time I pointed this fallacy to you in this thread.

The trajectory of the lead ball depends on its initial velocity, so, if it thrown parallel to the ground, it will not fall vertically but it will follow a parabola. Light will also follow a (different) parabola. Instead of posting rubbish questions, as you have been doing forever on this forum (and others), why don't you check into getting into a class, as you promised earlier?

YOU, are not dealing with anything, let's make this clear. In the Earth frame, being an accelerated frame, the paths of the light and the lead ball are different. You will never be able to learn physics by posting questions. You need to go to school.

In the freefalling frame the lead ball doesn't fall, it floats. Did you get that? It is the third time I explained it to you. Neither does the light, it moves parallel to the "floor". In an accelerated frame, like the observer hovering at infinity, the situation is different.

Nope, you are as wrong as before. A photon and a lead ball will "fall" at DIFFERENT speeds towards a gravitating mass. This is true from the perspective of any observer. I already pointed out your error when judged from the POV of a freefalling observer. (light "falls" at c, the lead ball falls at v=0).

Actually, you are outright lying. Here is the proof. Do us a favor and stop rubbishing the thread.

No, it wasn't, the subject was his false claims about my post due to his misrepresentation of my post. This is probably the closest you'll come to admitting that you were wrong all along.

Yes, correct. But this is not the subject of our disagreement. This IS the subject of our disagreement. In simple( r ) words, since you have so much trouble understanding: the math shows that massive particles follow a DIFFERENT trajectory than massless particles. In your parlay, the do NOT "fall the same way". Do you get this?

Yes, but I was objecting to something ELSE: your use of "fall the same way". What I labelled as psychobabble is your prose that reflects the lack of understanding of the basic equations of motion, as derived for massive vs. massless particles. I did not ignore it at all, I actually answered. The fact that you cannot follow the answer is your problem. "For the photon, it is a lot simpler, start with : [math]0=ds^2=(1-r_s/r)(cdt)^2-dr^2/(1-r_s/r)-r^2d\phi^2[/math] The above produces: [math](1-r_s/r)dt/d \lambda=\bar{k}[/math] [math]r^2d\phi/d \lambda=\bar{h}[/math] [math](dr/d\ \lambda)^2=\bar{k}^2-(1-r_s/r)(\bar{h}/r)^2[/math] where [math]\lambda[/math] is the affine parameter, different from ds. The above is the same thing (written differently) as my earlier [math]0 =- \Gamma^{a}_{bc}\frac{dx^b}{d \lambda}\frac{dx^c}{d \lambda} [/math]. Solving the above gets the light bending in a gravitational field. Contrary to your repeated claims, the photons and the massive particles don't "fall the same way". whatever that might mean. They take different paths since their equations of motion are different. For example if you let go of a test probe and of a photon from the same point, they will follow different trajectories." I recommended earlier that you stopped trolling my posts. You keep imagining errors in my posts and you are rubbishing the thread.

"Fall" means nothing but psychobabble. It is very simple, really, as I tried to explain to you earlier (sorry I failed). One starts with the metric (Schwarzschild, for example): [math]ds^2=(1-r_s/r)(cdt)^2-dr^2/(1-r_s/r)-r^2d\phi^2[/math] Since you had so much difficulty with understanding the geodesics equations, I'll explain another way, via the Euler-Lagrange formalism. Divide by [math]ds^2[/math] and you get the Lagrangian: [math]L=(1-r_s/r)(cdt/ds)^2-(dr/ds)^2/(1-r_s/r)-r^2(d\phi/ds)^2[/math] From the above, one gets the Euler-Lagrange EQUATIONS of MOTION (fully equivalent to the equations I presented earlier, in terms of Christoffel symbols): [math](1-r_s/r)dt/ds=k[/math] [math]r^2 d\phi/ds=h[/math] Solve the above and you get the trajectory for a massive particle. The above is the same thing (written differently) as my earlier [math]\frac{d^2x^a}{ds^2} =- \Gamma^{a}_{bc}\frac{dx^b}{ds}\frac{dx^c}{ds} [/math], For the photon, it is a lot simpler, start with : [math]0=ds^2=(1-r_s/r)(cdt)^2-dr^2/(1-r_s/r)-r^2d\phi^2[/math] The above produces: [math](1-r_s/r)dt/d \lambda=\bar{k}[/math] [math]r^2d\phi/d \lambda=\bar{h}[/math] [math](dr/d\ \lambda)^2=\bar{k}^2-(1-r_s/r)(\bar{h}/\bar{r})^2[/math] where [math]\lambda[/math] is the affine parameter, different from ds. The above is the same thing (written differently) as my earlier [math]0 =- \Gamma^{a}_{bc}\frac{dx^b}{d \lambda}\frac{dx^c}{d \lambda} [/math]. Solving the above gets the light bending in a gravitational field. Contrary to your repeated claims, the photons and the massive particles don't "fall the same way". whatever that might mean. They take different paths since their equations of motion are different. For example if you let go of a test probe and of a photon from the same point, they will follow different trajectories.

I find the above quote extremely amusing since it is a discussion between two very well known cranks (Pentcho Valev and John Duffield). One piece of advice: you will NEVER learn physics via (selective) quoting. Mine quoting (crackpots) will never get you to learn physics. But I am repeating myself.

Yes, your post was very clear. Was also very wrong. Based on your follow-on, you still don't understand how wrong it was.

Let's try again, using math instead of psychobabble: "You start with the geodesic equations: [math]\frac{d^2x^a}{ds^2} =- \Gamma^{a}_{bc}\frac{dx^b}{ds}\frac{dx^c}{ds} [/math] For light, the left hand side of the equation is zero (light is not subjected to acceleration): [math]0 =- \Gamma^{a}_{bc}\frac{dx^b}{ds}\frac{dx^c}{ds} [/math] For massive particles, the left hand side of the equation is NOT zero. The right hand side is the same, for both photons and for massive particles." This is precisely what I wrote, in precise mathematical terms. This is basic textbook stuff. Do you have any issue understanding the above? The above is correct but this is not what you asked. What you asked is this nonsense: Do you understand the difference?

Photons do not accelerate. The local speed of light (in vacuum) is invariant. Since there is NO acceleration you have no reason to call it...acceleration. Nope.

You need to stop trolling at some point. Especially since you amply demonstrated that you clearly don't understand the basics. In other words, you "don't do math". Well, the language of physics IS math, you should try learning how to express your thoughts in math form. Until then, any debate with you is leading nowhere.

In the free-falling frame light moves at c. All other objects do not move wrt the frame (they all float within the frame since they are freefalling just the same). Do you have problems understanding this? Correct. Using math makes answers unambigous. If you do not understand what I wrote, just ask. I will explain it to you. This is incomprehensible, so it is not answerable.

Err, you claim that "That isn't true" and you follow by repeating my exact sentence. Pay more attention when you read, please. Who said that they are accelerating? Are you reading what I wrote or are you making up things?

A free falling frame is inertial. By contrast, an observer hovering at a certain distance from the gravitating body must be accelerating (constantly), so he's not in an inertial frame. The two situations are not equivalent. Excellent idea.

Tough. You need to take an introductory class. The language of physics is math.

No, it doesn't, I already explained that to you in the previous post You start with the geodesic equations: [math]\frac{d^2x^a}{ds^2} =- \Gamma^{a}_{bc}\frac{dx^b}{ds}\frac{dx^c}{ds} [/math] For light, the left hand side of the equation is zero (light is not subjected to acceleration): [math]0 =- \Gamma^{a}_{bc}\frac{dx^b}{ds}\frac{dx^c}{ds} [/math] For massive particles, the left hand side of the equation is NOT zero. The right hand side is the same, for both photons and for massive particles.

This is not true, GR teaches us that photons move DIFFERENTLY from massive particles in a gravitational field. Photons follow null geodesics, massive particles follow non-null geodesics, the equations of motion are different.

You got it backwards: if you are ignorant of basic science you will never be able to create a viable theory.

I cannot parse the above word salad but I can tell you one thing: you seem to mix in the "Twins Paradox". The short answer is that twins are not symmetric, the one that "turned around" had to experience a longer path through spacetime. In relativity, longer path through spacetime means (paradoxically) shorter elapsed proper time. If you want to learn relativity, I suggest that you: -take a class -read a book ("Basic Relativity" by Robert A. Mould is an excellent, modern treatment and you can get it for only 18$ on Amazon). Posting word salads and asking people to unwind them is not the proper way of learning.