# Real equation of Force F = ma not dp/dt

Discussion in 'Alternative Theories' started by martillo, Aug 4, 2019.

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Good joke!

3. ### przyksquishyValued Senior Member

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I'm not interested in hearing how great of a visionary you think you are. You have pointed out (correctly) that there are situations where the formula $\boldsymbol{F} = \frac{\mathrm{d}\boldsymbol{p}}{\mathrm{d}t}$ doesn't apply and it would be incorrect to use it, for example in nonrelativistic physics if $\frac{\mathrm{d}m}{\mathrm{d}t} \neq 0$. This is already well known and explained in textbooks and on Wikipedia.

Now, do you have any evidence of physicists using the equation $\boldsymbol{F} = \frac{\mathrm{d}\boldsymbol{p}}{\mathrm{d}t}$ where it is wrong to do so? Yes or no.

5. ### martilloRegistered Senior Member

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Well, it is largely used in Relativity with a variable "relativistic mass". For instance here http://www.emc2-explained.info/Emc2/Deriving.htm#.XUl4cPZFyM9 is the "natural" derivation of the equation E = mc2 using the relation F = d(mv)/dt = dp/dt with the variable "relativistic mass" m = m0/root(1 - v2/c2). So for me E = mc2 is coming here from a wrong relation. The right relation is F = ma = mdv/dt with variable mass. In my theory E = mc2 is valid for photons but because of a different physical phenomena: the internal energy stored in the internal electric and magnetic fields of the particles which are not point-like particles but have structure and shape.

Last edited: Aug 6, 2019

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8. ### martilloRegistered Senior Member

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Yes, the web site and book is all about the structure of the elementary particles explaining it all.

9. ### Beer w/StrawTranscendental Ignorance!Valued Senior Member

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IMO you've made some high claims. So, how long have your ideas been out there/published in order to have others be critical with it aka experimentation?

10. ### przyksquishyValued Senior Member

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First, on terminology: there are two different quantities called "mass" in relativity. The first is so-called "relativistic mass" and the second is "rest" mass. Nowadays when we speak of "mass" in relativity, without a qualifier, it usually means the rest mass. The concept of relativistic mass is nowadays considered archaic. You'll usually only see it referred to in old papers on relativity and pop science (books and websites, like the one you linked to, that are written for people who aren't physicists).

Not in relativity which, remember, is a different theory than nonrelativistic Newtonian mechanics. In relativity, the force and momentum of a closed system (like a point particle or small billiard ball) are -- basically by definition -- related by $\boldsymbol{F} = \frac{\mathrm{d}\boldsymbol{p}}{\mathrm{d}t}$ where the momentum $\boldsymbol{p}$ is related to the (rest) mass and velocity by $\boldsymbol{p} = \gamma m \boldsymbol{v}$. This means that, in relativity, the relation between force and acceleration is something more complicated than $\boldsymbol{F} = m \boldsymbol{a}$, which I wrote in my last post.

11. ### martilloRegistered Senior Member

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Considered archaic just because brings lot of problems that physicists want to avoid.

What a hell is that? You mean there's a special definition for force to make Relativity work? That's absurd. The true definition of Force is unique and is F = ma. Rocketry dynamics shows it. If Relativity cannot work with that is a wrong theory.

Last edited: Aug 6, 2019
12. ### martilloRegistered Senior Member

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I have been developing the theory for about twenty years showing it in my book and partially in my web site since about 2005 but as it disagrees with Relativity nobody got interested. All criticism remained to my argumentation against Relativity. Actually nobody even read my propositions with proper attention I think. Nobody got interested and so I continued perfectioning it alone untill nowadays. Let me say that at this time I know it works pretty well.

Last edited: Aug 6, 2019
13. ### przyksquishyValued Senior Member

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No, the real reason is more mundane: we could define mass as $m = \gamma m_{0}$ in terms of rest mass but it turns out it just isn't very interesting or useful to do that in the end.

No it doesn't. You are confusing different things here. Nonrelativistic mechanics for an open system (like a rocket + changing amount of fuel) does not tell us how we should define force for a closed system in relativistic mechanics.

That is not a scientific argument.

If you want to feel that way then fine, but then you're just going to have to agree to disagree with physicists here. This is because relativity is accepted by physicists on scientific grounds (it is self consistent and correctly predicts the results of experiments) while you are dismissing it on ideological grounds (you just don't like how it does things).

14. ### martilloRegistered Senior Member

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"Ideological grounds"??? What is that??? Surelly not. I dismiss Relativity Theory because I have another theory that for me is much better. You know that. We both have been discussing in the forums for long long time and you know about. My approach can be said as non scientific because I didn't wait for each step on the development to be proven even experimentally. If I would have tried that I would have done nothing. I took a totally rational approach matching all experiments I could analyze, may be the most famous ones only I know. The theory agrees with all of them although they must be interpreted in a different way as it is done. My approach hasn't been taken seriously because of the disagreement with Relativity Theory. You are one that did that. What you don't know is how well the theory works in so many subjects. You didn't give yourselves the chance to realize about that. You are for instance in vain trying to find things like "dark matter" to validate Relativity with some galactic observations. On another side you are in vain trying to compatibilize Relativity Theory with Quantum Physics. My approach was to dismiss both to build a totally new theory about everything and I did it. But you don't give the chance to analyze that. Some day it will be done. I'm waiting for that. Meanwhile I sometimes present my findings in the forums to discuss like with this one. It's not a scientific approach, I know, but I think is the right one, at least for me. That's also why I'm posting here in the alternative theories' forum. Let me thank all of you for your time to criticize my subjects. Let me say this way the theory gets perfectioned more and more with time. I would prefer something different, to find someones really interested in the new propositions of the theory and may be even developing it further. Is not the case for now but it will be, sooner or later it will be. That's what I think and feel.

Last edited: Aug 6, 2019
15. ### billvonValued Senior Member

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Perhaps you consider it archaic because you do not understand it, or want to avoid it. But competent physicists really have no problems with it.

16. ### przyksquishyValued Senior Member

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Nobody is going to take you seriously because dismissing modern physics like relativity and quantum physics is simply not going to work, and that is even if these theories are wrong. Yes, we've discussed in the past, and I've told you in the past why this has no chance of ever working and what you would need to be doing differently, and you haven't learned from that.

But I'll try again. Ignoring existing physics will never work because, if you want to propose a new theory and be taken seriously, the minimum standard is that you need to show you can replicate the successes of these old theories that we already have. That means that your theory needs to be mathematically detailed and you need to prove, mathematically, that it can correctly predict the results of all the relevant experiments that have been done in the past whose results the old theories already predict correctly.

The problem with this is, there are thousands and thousands and thousands of such experiments, and new ones are published every day. That's far too many to go through and explain the results one by one. The only sane way to do this, that has any chance of working, is by leveraging the old theories. We know these theories already summarise a lot of experimental results because we've been testing them against experiments for decades and sometimes centuries. So what you need to do is prove that you can derive these old theories, mathematically, from the new one you want to propose.

Now I've seen your website and this is, for me, where it falls completely flat. Say you want to replace quantum physics. Well, I studied quantum physics in university and I happen to know that it is represented by a certain mathematical structure based on operators and Hilbert spaces and the Schroedinger equation and Born rule. I also know that you will need to be able to derive this mathematics from your own theory, since that is the only possible way you can convincingly replace quantum mechanics that has any chance of succeeding in my lifetime. But, when I look at your website, ultimately nothing there suggests to me that you even know the mathematics of quantum physics, let alone that you have any idea of how to even start to derive it from some different mathematics associated with a classical theory.

You probably won't like this, but whether you like it or not it is the hard truth and there is no escaping this. You simply can't replace theories you don't know because the only practical way of replacing them requires you to know them.

17. ### martilloRegistered Senior Member

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Thanks for your opinion but I still believe in this, my own way.

18. ### Write4UValued Senior Member

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You do realize that any equation is an expression of relativity, no? There is no such thing as an unrelative equation.

19. ### martilloRegistered Senior Member

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The following set of equations is incompatible with Relativity Theory:

F = ma
p = mv
dp/dt = mdv/dt + vdm/dt = ma + vdm/dt = F + vdm/dt

And Rocket's Dynamics demonstrates it right.

20. ### Write4UValued Senior Member

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Can you offer a narrative to those equations? How and why can an equation be other than relativistic?

Are you addressing the differences between GR and QM?

Last edited: Aug 6, 2019
21. ### martilloRegistered Senior Member

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That set of equations is valid and used for the thrust equation of rockets. Particularly F =ma = mdv/dt even with a variable mass m.
Relativity considers F = dp/dt = d(mv)/dt with the mass varying with the Lorentz's factor 1/root(1 - v2/c2).
The two are different and incompatible definitions for Force. If one is valid the other is not.

Last edited: Aug 6, 2019
22. ### Write4UValued Senior Member

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What is non-relativistic about Newton's Third Law; "for every action there is an opposite and equal reaction" ?

A frame-of-reference (a dynamical state) does not need to be of a physical nature. It can be theoretical, yet relativistic.

23. ### Write4UValued Senior Member

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By measuring each singular instance of mass. You are making a comparison to a constantly variable dynamic system, which does not allow for rigid mathematics. This then becomes probabilistic. But regardless, each instance is a relativistic phenomenon, even if only to the observer's POV.

Occurs to me that your argument is similar to advocating that the wave/particle duality is not a relativistic state.