Ghideon

The accelerometer is at all times attached to mass m and hence moves with mass m wherever mass m is going. Again: Do you know what an accelerometer measures? Do you know that the acceleration the mass m experience is absolute and does not depend on frame of reference? I am not assuming anything. I read the measurement of the accelerometer attached to the mass m. The accelerometer is not physically moved. We look at the one and the same accelerometer that is attached to the mass m at all times.

As I have told you numerous times, my explanations covers all the times, including transitions and both frames of reference. Do you really know what an accelerometer measures? You claim that. You may have to read my answers in more detail. You are claiming that an accelerometer, for instance with a digital display showing the acceleration, attached to the mass m, will read one number when seen from rotational frame of reference while simultaneously reads another value seen from the inertial frame of reference. What kind of physical principle allows you to have a display on an accelerometer attached to mass m show for instance -2G in one frame of reference and at the same time showing the value of +3G when seen from another frame of reference? Nature does not work that way as far as I know. At least we seem to have found the core, were the invalid analyses comes from.

False. I speak of your example. Both at the time(s) with constant angular velocity and the time of accelerating angular velocity. Read previous answers. The measured acceleration may vary and is towards the centre. The acceleration may look different from different frames of reference such as a rotating or an inertial frame of reference. The fact that you misinterpreted your experience in a car (and many beginners have done so) have no effect on the laws of physics.

Then back up that invalid claim with evidence. Do not use more invalid arguments or new invalid claims. Or check any introduction to physics, the above seems to be based on a common misunderstanding among physics student. You are claiming that a accelerometer, for instance with a digital display showing the acceleration, attached to the mass m, will read one number wen seen from rotational frame of reference while simultaneously reads another value seen from the inertial frame of reference. I fail to see why you would claim that.

Wrong. My description of the physics is correct for any frame of reference. Your description is incorrect in all frames of reference. Do you really think the accelerometer, attached to the mass m, will measure a different acceleration in different frames of reference? That would imply that nature is full of paradoxes. I can't imagine you have this fundamental misunderstanding of physics, hence i asked: Do you know what an accelerometer does?

Not only that, but more imprtantly: False. An accelerometer attached to the mass m measures shows an inwards direction at all times. Don't try to avoid addressing that important misunderstanding. It seems to be a major source of the errors in your analysis? Do you know what an accelerometer does? Do you know that acceleration is absolute? The measured acceleration may vary and is always towards the center*. The acceleration may look different from different frames of reference such as a rotating or an inertial frame of reference. I speak of your example below. Both at the time(s) with constant angular velocity and the time of accelerating angular velocity.

Of course it can. But not important to the discussion as we are not interested in fine tuning the example. May I advice you to focus one the other more serious issues pointed out?

Do you know what an accelerometer does? Do you know that acceleration is absolute? The measured acceleration may vary and is always towards the center*. The acceleration may look different from different frames of reference such as a rotating or an inertial frame of reference. I speak of your example below. Both at the time(s) with constant angular velocity and the time of accelerating angular velocity. No. In classical mechanics, the Euler force is the fictitious tangential force[1] that appears when a non-uniformly rotating reference frame is used for analysis of motion and there is variation in the angular velocity of the reference frame's axes. https://en.wikipedia.org/wiki/Euler_force *) Again, as noted earlier In a perfectly tuned setting the accelerometer attached to mass m could possibly measure exactly zero during a short time.

Yes No.

Here is one source of confusion. When you say that mass m will accelerate outwards, you mean as seen in the rotating frame, OK? What will an accelerometer, attached to the mass m, show? Number not important yet, just direction. Does the concept of "Euler force" ring a bell? Given the title of your speculative thread the tangent force Swansont mentions should not be too unfamiliar.

False. Did I say that? I discussed the inertial frame of reference.

Would we be able to "see" gravitational events in that direction, such as massive black holes merging?

The mass m is accelerated, in the inertial frame of reference, towards the circle centre by non-fictitious force labeled the centripetal force. Forces that are present also in the rotating frame of reference. In the rotating frame of reference the coordinates for the motion of the mass m does not match the motion in the inertial frame of reference. We can fix that difference by adding a fictitious force in the rotating frame. This fictitious force does not affect physical "reality". Events happening i the rotating frame happens in the inertial frame and vice versa. Note that in the inertial frame of reference the mass m never accelerates out from the centre in your example. An accelerometer onboard the mass m will never register an acceleration* away from the circle centre, only a varying acceleration towards the centre. I have never experienced that. I have experienced a centripetal force resulting in a net force F>0 resulting in a change of direction AKA acceleration. (Given seatbelt is fastened and / or car door shut) I have also, as an engineer, experienced the efficiency of introducing a fictitious force such as centrifugal force to allow for calculations in an accelerated frame of reference. I am denying that inertial forces has physical effect and that nature is consistent. Have you observed some event, for instance a car sliding off the road, happen when seen from beside the road while not happening for this in the car? I have not. An nature seems to strictly force such paradoxes. Luckily our laws of physics covers that and maintain consistency when we change coordinate systems. For instance by introducing fictitious force in on frame of reference and not in another. *) In a perfectly tuned setting the acceleration could possibly be exactly zero (onboard the mall and in the inertial frame of reference) during a short time.

Non-real forces (fictitious) have no physical effect. You seem to have missed that point. ( but you agreed on it in the earlier analysis)

Unintentional or not, that is what you say, just check the answers from some of the other members. Implications of your invalid physics runs much deeper that you want to or are capable of seeing. Which is also one aspect that makes the thread interesting; there are so many completely different ways to describe where and how the proposed ideas fail to match theory and observation. From this thread one could possibly create an interesting infographic from pre-Newton to the latest take on cosmology and particle physics and in each section describe how reactionless drives have become more and more improbable. (Maybe I should start a separate thread on that) There have been plenty of math presented, Swansont gave you equations a few pages ago. We will start apply more mathematics once we have a proper description of the example. When asking for details the examples tend to get more and more complicated and details change. One could even believe that there is tweaking of the examples to get members to provide incorrect analysis. Hence we apply more rigour in the initial steps; applying correct mathematics to an incorrectly defined system way allow for unphysical results, that is easy to do. We are not going to get tricked into doing that, intentionally or unintentionally. Ok. Confidence is a good thing I suppose. So you are right and I am wrong because you say so, not very persuading way to argue against all current physics. Being incorrect is not that embarrassing, especially not on this forum, due to the friendly atmosphere among the members. And if I would find an error so that I was wrong and Newton does not apply (according to your claims) and also were able to confirm that, then it is a Nobel Prize level of discovery. And missing the Nobel prize, that would be embarrassing I guess. But that's just a fairy tale, nothing to do with science. Since you don't get the big picture though physics I'll try an analogy this time. We have natural positive numbers 1,2,3... and we have addition "+". There are rules how to perform addition and there are limits regarding the outcome. The sum of two positive numbers is positive. In this analogy your claims would be that the addition of two positive number sometimes should result in a negative sum. Members here try to show that the framework of mathematics does not work that way. Your answer is like "OK, my idea failed for 123+145 but wait I have another case, here are these two positive numbers their sum is suspicious, I believe the sum is negative, please analyse". This is how your physics looks from the outside. No matter how hard you look for different positive integers there is no way to find a pair that added together gets you a negative sum. And no matter how hard you try creating a classical mechanical system that have the properties you claim we know that within the framework of classical mechanics such a system cannot be described*. "the obvious" ? And we will get the result that the laws of physics predict. (Mainstream edition, not your personal interpretation) *) Within the applicability of course. You could, correctly, argue that Newton is wrong at relative velocities close to speed of light in vacuum. The natural numbers is an analogy, there may be situations outside the everyday usage of mathematics where it does not apply. For instance it may happen in certain computer architectures due to limited number of bits available for representations. But that is not the point with the analogy in this case.

Does your answer imply that you are not prepared to move back to basics and try again? So the simplest thing you could imagine is that all of Newton, Lagranage, Hamilton, Einstein, and down to the core of knowledge is wrong*. Your definition of "simple" seems to deviate from my definition. Thats cool, we knew that your claims were incorrect according to known laws of physics from your very first post. Question was if you wanted to stay wrong or eventually learn more physics. Me and @swansont will reach the same conclusion regarding inertial vs rotational frame of reference as long as we are able to make identical interpretations of your instructions. It can't be any other way since we use the same physical rules, principles and laws. I guess performing such an analysis will have to wait till such a time when your level of understanding matches the required explanations. Have you seen any support for your Newton circumvention here during the discussions here? Also not that this is just about some minor details of one specific example. The big picture regarding all possible examples and designs of this type was analysed and presented to you long ago. *) (Thats what you are implying to someone who know some physics)

It looks like you have misunderstood my explanation of the simple example* I posted; your analysis is not compatible with Newtons laws. Doing an analysis of the rotating frame is of limited value at this. I had some hopes that you had grasped the basics by now. For instance: Centripetal force is not an inertial force. So there is no way forward from here, we need to go back for a while: You said** You are back into expecting that Newton's laws does not apply, are possible to circumvent or have "alternative interpretations". So somewhere along the line you failed to understand, point out where so we may restart at the right location. Your own example is too advanced for you at this time, you need something simplified first. *) Constant angular velocity, two frames of reference **) https://www.scienceforums.net/topic/123261-circumventing-newtons-third-law-through-euler-inertial-forces/?do=findComment&comment=1157186

Ok. Your analyse was wrong the previous time and is still wrong.

I am serious but maybe use incorrect words. As seen from an inertial frame of reference the mass m is at all times in centripetal acceleration. Acceleration means force, F=ma. In the inertial frame of reference mass m is never at rest, mass m is never moving with constant velocity, mass m is accelerating towards the centre of the circle. The rod has friction so the mass m can't slide free along the rod, the friction slows down any radial movement along the rod. That friction means that the rod is, at all times, able to affect the mass m with a centripetal force. The force is not constant but you have not stated anything saying the force can be zero. Under those circumstances the rod is the object that applies the force that accelerates mass m. Feel free to provide an alternative.

Yes. Is there anything else that the mass m is attached to? As long as there is non-zero friction and angular velocity w>0 the rod is pulling the mass m in radial direction We can assume a negligible non-zero mass then. (massless does not imply zero friction) There are only six threads with more answers in the speculations section. I'm aiming for the record.

The centripetal force is directed towards the centre, the rod accelerates the mass m. The rod is affected by an equal and opposite reaction force. Can we assume the rod is massless?

If the mass is accelerating in the inertial frame of reference there is limited degrees of freedom for the direction the mass can accelerate in. It is tangential due to increased angular velocity and towards the centre due to centripetal force, OK?

I will not sidetrack @swansont's analysis and do not yet have sufficient information to give an exact answer. Do you include the green forces I have added to the picture? It is the force acting in tangential direction pushing at the mass when angular velocity increase and the reaction force from the mass to the yellow rod. Since you have friction included, those forces may or may not have an impact. Again, they shouold only be present during the period of time the angular velocity is increasing.

If the mass accelerates in the inertial frame of reference there is a force* acting on the mass. And therefore an equal and opposite reaction force. *) Not fictitious force.

Ok. Then you realise that Newton holds, there is no room fo any "interpretation" or circumventing. We apply the correct laws to your example and check the outcome. Ok?