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a reply to: Zanti Misfit

Can a body have a constant speed but a varying velocity ?

you need to understand the difference between speed and velocity
velocity means speed and direction at the same time

YES, same speed but varying direction

Can a body have a constant velocity but a varying speed ?

YES, it moves in the same direction but with different speed over time

Can a body have a zero velocity and finite acceleration ?

NO, velocity means speed and direction, acceleration means change of speed or direction
zero velocity, no speed or direction, no acceleration.

a reply to: Zanti Misfit

Look up inertia. This is probably something you can solve for yourself.

a reply to: Arbitrageur

Ok, can anyone give me a little background on how the curvature/shape of spacetime inherently prevents any traveller from ever being able to reach the "edge" of the expanding universe? Besides the obvious limitations of distance and possible velocities.

originally posted by: Zanti Misfit
a reply to: Arbitrageur

Can a body have a constant speed but a varying velocity ?

Can a body have a constant velocity but a varying speed ?

Can a body have a zero velocity and finite acceleration ?

Velocity can refer to average or instantaneous velocity. By the way your question is worded we should assume instantaneous velocity is implied.

The definition of speed can be a little more ambiguous. Some books define it as the distance divided by the time, but what is meant by distance is not always clear. Let's say you drive east one block at 20 kph and north one block at 20 kph. How do you want to measure your distance? Is it the 1 block plus 1 block you actually traveled, or is it the distance as a crow flies which is only 1.41 blocks?

NASA gives a different definition of speed: "speed is the scalar magnitude of a velocity vector". Since you didn't provide any definitions of your terms, I'll use this definition of speed to answer your question.

Can a body have a constant speed but a varying velocity ?

That's accomplished in the example I just gave of driving east one block at 20 kph and north one block at 20 kph. The speed of 20kph is constant but the direction changes from East to North so the velocity isn't the same.

Can a body have a constant velocity but a varying speed ?

If you adopt the definition NASA provided that "speed is the scalar magnitude of a velocity vector", constant instantaneous velocity implies that both magnitude and direction of the velocity remain constant, and if speed is the magnitude then it too must also be constant.

Can a body have a zero velocity and finite acceleration ?

Yes, just toss up a ball and let it fall back down.
There will be an instant where it stops moving up before it starts moving down. At that instant the instantaneous velocity is zero, yet the ball is under constant acceleration toward the earth.

originally posted by: KrzYma
a reply to: Zanti Misfit

"Can a body have a constant speed but a varying velocity ?"

you need to understand the difference between speed and velocity
velocity means speed and direction at the same time

YES, same speed but varying direction

"Can a body have a constant velocity but a varying speed ? "

YES, it moves in the same direction but with different speed over time.

I can't imagine how you think varying the speed in the same direction yields constant velocity. Both magnitude and direction must be constant for velocity to be constant, not just one or the other.

"Can a body have a zero velocity and finite acceleration ?"

NO, velocity means speed and direction, acceleration means change of speed or direction
zero velocity, no speed or direction, no acceleration.

As explained above the answer is yes but not for very long, only for an instant. So you're one for three; maybe you should be asking the questions instead of answering them. I also think your qualifications for rewriting mainstream physics are in question if you think varying speed in the same direction is a constant velocity.

There's also the equivalence principle in general relativity, but I'm keeping the answer simple for now. If anybody wants to research it further, note Einstein said this:

en.wikiquote.org...

We shall therefore assume the complete physical equivalence of a gravitational field and a corresponding acceleration of the reference system.

Albert Einstein, Statement of the equivalence principle in Yearbook of Radioactivity and Electronics (1907)

originally posted by: KrzYma
now, the electron and proton is not really some point like particle, those have a volume, they are not infinitely small. They are spheres with surface areas, which is very significant indeed.

Did you read somewhere that the proton is a point-like particle? It seems you're trying to refute that straw claim which i didn't hear anybody make.

That has been said about the electron, but if you dig deeper than a "sound byte" you can find different ways of trying to measure the size of an electron, such as the Bohr radius, the classical electron radius and the Compton wavelength, all of which have issues. There are other experiments which place the maximum size of the electron at 10E-18m. Some of that is explained in this blog post. The real size of an electron doesn't seem to be known for sure but by itself it's very small, though it can present a bigger profile as part of an atom.

The eather is displacing its EM gradient ( magnetic with speed C, electric instantly (? to be confirmed) )

How is that going to be confirmed?

So when you see the light from the sun, nothing traveled from there to here. No photon that moves with the speed of light..
...
it does not move ! EM radiation propagates...

I don't have an issue referring to the propagation of electromagnetic radiation but even if it propagates, doesn't light still take about 8 minutes to get from the sun to the Earth?

originally posted by: KrzYma
a reply to: Arbitrageur

If you remember I told you about the density of eather.
That one + charge particle and one - charge particle "produce" a density of 2 with a net charge of 0. So nothing to detect in terms of charge but still 2 in density.

When NIST moves the optical clock 0.5m the density in EM changes.
They move it away from the density source, the Earth.
EM propagation is dependent on the density, denser = slower propagation
That is why EM waves bend in present of "mass" because one side of the wave is propagating slower than the other. So the gradient in EM "bends" when it propagates.
So do the counting intervals in NIST optical clock, not Time !

Thanks for trying to explain but I still don't understand the difference between time and the counting intervals in the NIST clock. I guess I'll just give up while I'm behind in trying to understand you, plus some of your misunderstandings of very simple concepts like saying varying speed yields constant velocity tell me I shouldn't put more effort into trying.

So is it the angle of the dangle = the mass of the ass or is it, the the mass of the ass = the angle of the dangle?

Is there a diff?

originally posted by: burgerbuddy
So is it the angle of the dangle = the mass of the ass or is it, the the mass of the ass = the angle of the dangle?

Is there a diff?

Lol , nice one. Haven't heard that expression in a long while

a reply to: burgerbuddy

You forgot to factor in the coefficient for the swing of the thing.

a reply to: roguetechie

And the tangent of the taint

originally posted by: pfishy
a reply to: Arbitrageur

Ok, can anyone give me a little background on how the curvature/shape of spacetime inherently prevents any traveller from ever being able to reach the "edge" of the expanding universe? Besides the obvious limitations of distance and possible velocities.

The three possible simple geometries are:

1. No curvature (angles of triangle sum to 180 degrees, also called flat)
2. Positive curvature (angles of triangle sum to more than 180 degrees, also called spherical)
3. Negative curvature (angles of triangle sum to less than 180 degrees, also called hyperbolic or saddle-shaped)

There are also more complex geometries possible, maybe even some combination of above with regional variations.
Attempts to measure curvature indicate mostly #1, flat which could be infinite, but that could also be the result of a more complex shape like a torus which would be finite (which seems unlikely to me but we should still consider possibilities).

2 and 3 are other possibilities which while not suggested by flatness measurements, can't be ruled out since we can only put limits on flatness, like curvature is below x amount. Positive curvature or spherical would suggest you could travel in one direction and end up back where you started, sort of like flying around the Earth, except in 3-D instead of flying over a surface like an airplane does. You can't really draw this spherical universe concept, it's mathematical.

Some of the problems with trying to measure flatness relate to the need for a "standard yardstick" which we can use to tell how big something far away is, and we've made some estimates of that, but one problem is that the dynamic and evolving nature of the universe means we aren't looking at something that's constant in time. So when things look different in the past, is it because of the geometry of the universe, or because the universe started from a big bang and is evolving and that's why things look different? We can estimate some of that of course but it does put some uncertainties in our measurements which I suspect could be a source of the "tension" mentioned in papers like this.

Falsifying ΛCDM: Model-independent tests of the concordance model with eBOSS DR14Q and Pantheon

We combine model-independent reconstructions of the expansion history from the latest Pantheon supernovae distance modulus compilation and measurements from baryon acoustic oscillation to test some important aspects of the concordance model of cosmology namely the FLRW metric and flatness of spatial curvature. We then use the reconstructed expansion histories to fit growth measurement from redshift-space distortion and obtain strong constraints on (Ωm,γ,σ8) in a model independent manner. Our results show consistency with a spatially flat FLRW Universe with general relativity to govern the perturbation in the structure formation and the cosmological constant as dark energy. However, we can also see some hints of tension among different observations within the context of the concordance model related to high redshift observations (z>1) of the expansion history. This supports earlier findings of Sahni et al. (2014) & Zhao et al. (2017) and highlights the importance of precise measurement of expansion history and growth of structure at high redshifts. ...

Fig. 3 shows Θ(z) (top) and O k (z) (bottom). Both are consistent with a flat FLRW metric up to z ’ 1.2.
However, at high redshift, some deviation from flatness can be seen.

(emphasis mine). So up to redshift of z=1.2 the universe appears flat, but over that, they talk about "tension" which means something like observations don't quite agree with the model as-is. Coming up with an accurate model to include all aspects of the evolution of the universe is no small feat, so I don't necessarily assume that the deviation from flatness over z of 1.2 is necessarily accurate when it could be a problem with the model or assumptions used in the calculations. I don't think we really know the true geometry of the universe at this point, but we can put some limits on it.

Even if the universe had an edge which it may not have, I wouldn't easily dismiss the problem that even the edge of the observable universe is receding at about three times the speed of light, and any edge of the universe beyond that would be receding even faster.

a reply to: Arbitrageur

Wow. Excellent response. Thank you

originally posted by: Hyperboles
a reply to: Arbitrageur

Isn't SOHO still orbiting the central black hole of our galaxy?
Get soho to measure the period of the pendulum using a mechanical stop watch, or use the value of g due to the central black hole to calculate the period. Now what is the value of this g, i do not know as yet, but will try to find it out for you.

You should really learn Newtonian mechanics before you try to say a pendulum proves relativity is wrong.

When you let go of an apple, it falls according to g, the gravitational acceleration of the earth at the surface, about 9.8 m/s^2

Now change reference frame to the international space station. What is the value of "g" there? It's about 0.9 times the value of g at earth's surface, or 0.9 x 9.8 = 8.82 m/s^2.

So an astronaut lets go of an apple aboard the ISS. Does it accelerate toward earth 90% as fast as it does at earth's surface? Yes? No? It depends on your reference frame. If your reference frame is inside the ISS, you don't see the apple appear to accelerate in any particular direction, why not? Why does it just "float" there? If you figure out the answer, remember the answer applies to any stable orbit, including the argument you're trying to make for the value of g due to the central black hole (which isn't even a valid way to look at it, because even the milky way's supermassive black hole has only a small fraction of the galaxy's mass). Regardless of what that "g" is, if the sun isn't spiraling toward the milky way center, or spiraling away from the center, then it's in a stable orbit similar to the ISS in a stable orbit around the earth and something is offsetting the "g" in both cases to prevent spiraling in decaying orbits. See if you can figure out what that might be and what effect it has on a pendulum in a microgravity environment.

Here are two more thought experiments to get you thinking about what the pendulum would do. What do you think it would do in these two cases, and what value of g would you use to determine the period of the pendulum?

A. Let's say aliens make a duplicate of the ISS and instead of placing it in orbit, they place it 200 miles above the north pole (roughly the same height as the ISS). So, the ISS would accelerate toward the north pole starting at 8.8 m/s^2. Is 8.8m/s^2 the value you'd use to calculate the period of the pendulum? why or why not? What value would you use?

B. Let's say aliens make another duplicate of the ISS and instead of placing it in orbit, they place it 200 miles above the north pole (roughly the same height as the ISS). However in this case, they make it stay at an altitude of 200 miles by attaching a cable to their super advanced space ship. So the ISS would not accelerate toward the north pole at 8.8 m/s^2 because the cable attached to the alien space ship prevents that. Is 8.8m/s^2 the value you'd use to calculate the period of the pendulum? why or why not? What value would you use?

originally posted by: delbertlarson
There seems to be a hierarchy of how ideas get accepted. Everyone seems to want to get validation by someone who is a "known expert". But those known experts are just people too. I wish everyone would just think on their own.

Of course, but I must say I've always had a lot of respect for Freeman Dyson and his genius. I heard his son talking about a part of his life where he described the story as "son builds world's highest treehouse to try to get out of his father's shadow". I suppose when your father is that famous and widely recognized for his genius it's hard to follow in your father's footsteps. Anyway for all the genius Dyson has which many people respect, you said you watched the video of him presenting the progress he and his graduate students had made to Fermi, who told him he wasn't impressed and thought they were on the wrong track. Even more amazing is how Dyson seemed to be convinced by that advice, saving him and his graduate students maybe 20 man-years of work in the wrong direction, since eventually evidence proved Fermi's take was correct. So if that doesn't provide some suggestion of the value of a "known expert", like Fermi in that case, I don't know what will. Of course Dyson still thought for himself, but he found Fermi's arguments compelling and his insights to be valuable. That story made an impression on me, how could saving that many man years of wasted effort not be impressive?

originally posted by: prevenge
a reply to: Arbitrageur

If crop circle images act as sufficiently efficient engineering components, then why aren't they used to produce higher levels of energy production for the masses?

Using chalk circles results in greater efficiency. You need some experts to distinguish between the "real" circles, and the ones made by humans, whether talking about crop circles or chalk circles. For example, if you find magnetized iron filings near the center of the circle, it must be "real" because no human being could ever think of sprinkling magnetized iron filings in their crop circle, and even if they thought of it, why would they do such a thing? Or that's what the "experts" tell me anyway.

originally posted by: Arbitrageur
I must say I've always had a lot of respect for Freeman Dyson and his genius. I heard his son talking about a part of his life where he described the story as "son builds world's highest treehouse to try to get out of his father's shadow". I suppose when your father is that famous and widely recognized for his genius it's hard to follow in your father's footsteps. Anyway for all the genius Dyson has which many people respect, you said you watched the video of him presenting the progress he and his graduate students had made to Fermi, who told him he wasn't impressed and thought they were on the wrong track. Even more amazing is how Dyson seemed to be convinced by that advice, saving him and his graduate students maybe 20 man-years of work in the wrong direction, since eventually evidence proved Fermi's take was correct. So if that doesn't provide some suggestion of the value of a "known expert", like Fermi in that case, I don't know what will. Of course Dyson still thought for himself, but he found Fermi's arguments compelling and his insights to be valuable. That story made an impression on me, how could saving that many man years of wasted effort not be impressive?

Thanks for your story about Dyson and Fermi. A critical difference between that and what I presently face however is that lately I tend to get no response at all. I would dearly love valuable critique. 25 years ago I could at least get something from PRL. Now the editors simply dismiss me without review.

As I've mentioned before, in the old days I could get excellent reviews. A reviewer found I had missed a fundamental length in my aetherial Maxwell Equations derivation. (It was needed dimensionally for my arguments, but otherwise my arguments stood.) I was also able to exchange letters with John Bell, who corrected me early on in my attempted derivation of the Lorentz transformation without a length contraction. In both instances the identification of my error was critical to achieving a correct derivation. I might have found the error in time myself, but at the least it saved a lot of time, so I remain very thankful for their assistance. This is similar to your story about Dyson and Fermi. The problem I have now is that everyone wants an expert to validate my work, and the experts don't respond. So it would be great if everyone could think things through themselves. My work is far simpler than the status quo, so it can be done.

I think one root of my present problem is that I haven't "worked in science" for about 20 years now so I don't have "the cred". Back when I got reviews I was a rising young physicist. I had developed a new 3 MeV electron cooling technology (John Bell's wife worked in electron cooling) and worked at what was to be the worlds leading lab - the SSC. In the past 20 years I've made my living in IT, and it is places like that where crank papers often come from.

I think a second root of my present problem is the issue of crankiness itself. Since I am proposing changes to just about everything fundamental to physics, the instant reaction is rejection without taking any time to think about it. But if one does take the time one can see that while I am proposing fundamental changes, the vast majority of fundamental equations remain. Maxwell's equations, the Lorentz force equation, and the Lorentz transformation all remain. The preon model is just a deeper understanding of quarks and leptons; quarks and leptons remain. The problem is getting anyone to critically dig deep enough into my work in order to see that.

I do keep trying. I was thankfully provided an email address to Susskind, and I sent Susskind a similar email to the one I sent to Nima Arkani-hamed that you helped me with last September. No response. No surprise. Today I began a hard copy letter and plan to send it to Nima Arkani-hamed tomorrow. I have already formulated a first draft. It is based on the September email, except this time I am putting my credentials first. When reading it, I realized (as you did back in September) that he might just quit reading half way through thinking it is a crank effort and hence never know of all the successful work I did with mainstream "relativistic" accelerator designs and constructions. Perhaps that successful past might encourage some thought about what I propose.

I do wish to thank you again for your responses, and I hope you have time to view and comment on the video I linked to in a thread a few days ago. The video gets to the heart of the matter. But I am afraid that due to its length it hasn't been viewed much.

a reply to: Arbitrageur

Hey instead of considering inside iss or whatever. just consider the point ( the point needn't orbit anything ) in empty space and imagine your pendulum there or for that matter anywhere in this universe. will it swing, ofcourse it will.

a reply to: Arbitrageur

My above comment left out an important point. As stated, my work leaves in tact the Lorentz force equation, Lorentz transformation, Maxwell's equations, and all particle identifications consistent with quarks and leptons. However, my work does lead to some differences from the status quo, and those differences allow: instantaneous action at a distance for understanding quantum collapse; avoiding infinities by having small finite sizes to particles; elininating the need for the zero-point quantum fluctuations via a new high velocity quantum mechanics; and prediction of 18 specific energies at which high energy physics should find particles - 9 of which have been found.

I didn't want to leave the impression that my work leaves everything the same. However, most (not all) tests of nature involve those things that my work does leave the same.

a reply to: Arbitrageur

Is the Neutralino a part of nothing?
Like as its the equal with the plus and the minus, never and always?

a reply to: Drazzl

The Neutralino is a proposed supersymmetric particle. It has not been shown to exist, though is a candidate for particulate Dark matter... such as the WIMP.

Other than that... no idea what the question really is? care to expand on it?

originally posted by: Hyperboles
a reply to: Arbitrageur

Hey instead of considering inside iss or whatever. just consider the point ( the point needn't orbit anything ) in empty space and imagine your pendulum there or for that matter anywhere in this universe. will it swing, ofcourse it will.

The same question applies. What value do you use for g when calculating the period of the pendulum?

originally posted by: Arbitrageur

originally posted by: Hyperboles
a reply to: Arbitrageur

Hey instead of considering inside iss or whatever. just consider the point ( the point needn't orbit anything ) in empty space and imagine your pendulum there or for that matter anywhere in this universe. will it swing, ofcourse it will.

The same question applies. What value do you use for g when calculating the period of the pendulum?

The value of g is unimportant as long there is a positive value to it.
Just for the sake of illustration. take a table, erect a pendulum on it and place it on the earth which has variable g. Select any value of g that you can imagine pertaining to any point in this universe and the pendulum will behave as per the value you choose

originally posted by: Hyperboles
The value of g is unimportant as long there is a positive value to it.

Let's go back to your post in the other thread:

originally posted by: Hyperboles
a reply to: Arbitrageur

Pendulum will not stop at lagrangian but will stop at the event horizon of a black hole

If an the pendulum is orbiting at the lagrangian, for all practical purposes it does not see a positive g value in any direction which is not offset by its motion.

Likewise in the ISS reference frame, g doesn't have a positive value that I can see from watching the video below. At the lagrangian and in the ISS both are orbits and even if you add the galactic orbit you've still got this kind of situation where things don't fall in any particular direction as they would if there was an effective net g in that reference frame. Whatever g is there in an external frame is offset by motion, that's why things float. Remember the ISS is not only orbiting the earth but also the sun and the galaxy, and none of those seem to make objects fall in any particular direction aboard the ISS. If objects were falling in a particular direction, then you could measure that acceleration, and use that value to calculate the period of the pendulum.



But since you seem to be clueless about how orbital mechanics work, we can add that to the list of things you don't understand which keeps getting larger, unless you want to try to learn about it which I was trying to help you do with the thought experiment questions I posed for you, that you chose to not answer.