Need some help

Page 2 - Seeking answers about space? Join the Space community: the premier source of space exploration, innovation, and astronomy news, chronicling (and celebrating) humanity's ongoing expansion across the final frontier.
Here is a five year intensive study by Cornell University that shows that a partially liquid core plays a large role in (Mercury's) orbit.
I don't see that they address orbital relationships with cores. It is about spin. It's an interesting paper that shows Mercury likely formed much farther out then migrated inward. This is consistent with theories like the Grand Tack model where Jupiter migrated inward and wiped out the early planets, but then was pulled outward by Saturn, allowing new ones, fortunately for us, to form.

Core densities will alter their migration rate, in or out, due to angular momentum exchanges due to different rotation-revolution rates. But Mercury is tidally locked so I doubt there is much change in the orbit at this time.

Orbits and trajectories require energy or mass exchanges outside of itself. Spin is internal.
 

Catastrophe

"Science begets knowledge, opinion ignorance.
Wow. That's heavy duty! :)

Remember that to determine the angular momentum the mass of the body (ie Mercury) is required. So I would guess some mass value is needed for the equation, though a slight error may not have much effect as you note earlier.
Angular momentum is included as h? h= angular momentum in d²u/dφ² + u = GM/h² + (3GM/c²)u²
 
Yes. It’s more obvious in Newtonian physics.

Swinging a cannonball round and round has more angular momentum than swinging a Nerf ball. The only difference is mass, assuming the rope length and swing period are the same.
 

Jzz

May 10, 2021
237
63
4,660
There appears to be a basic dichotomy going on. The difference between the manner in which a solid and a liquid object spin, is part of human mythology, it has been used to tell apart boiled eggs from raw eggs for literally Millenia. Some particularly gifted persons can even tell apart well boiled eggs from partially boiled eggs by the act of spinning them. The point is that the difference in spins between objects with a solid core and those with a liquid core is based on observable, discernible, measurable, empirical facts. The question that then arises is this; when there is a choice between two options; one based on empirical facts and the other based on reasoned but invisible and (essentially) undetectable facts; which option is preferable? It has been reasoned here in this thread, that given the comparative mass of the sun and mercury, it is only the mass of the sun that determines the orbit of mercury. Obviously, this is not true for were it true, Mercury’s orbit would have been far less elliptical than it is, other unknown but ponderable reasons must be responsible for Mercury’s orbit. As regards its precession it appears that there is a general ignorance of the magnitudes involved. One arcsecond amounts to 1/3600 th of a degree. That is small, to say that a variation of 43 arc seconds per century is incredibly small is therefore no exaggeration. Given that this is so, isn’t it possible, if not probable, that this difference in the precession of the perihelion of Mercury is due to the movement of the partially solid core rather than to some fantastically complicated calculation involving the bending of space and time. Further, it should be considered, that this fact about Mercury’s core being partially liquid has only recently come to light through sophisticated probes and calculations and was not known at the time of Einstein’s General relativity explanation in 1915. n.b. Many thanks for link posted by Helio
 
Last edited:
Jzz, I think you are referring to Cat's link.

Your challenge to GR will require some powerful math to show how core densities can solve the old orbital puzzle, which was solved by GR to, eventually, everyone's satisfaction.

Newton had already shown how mass can be treated as a point location (center of gravity), which eliminates all density issues. This, I'm confident, is held to be true in GR.

But the math must be understandable even if it requires oversimplification as a precursor to the larger math model. Math that shows how an orbit can change due to internal activity (ie density changes) will be key, I suppose.

The only change I can imagine to an orbit due to internal behavior would come from the orbital shift in mass. Since energy is equated to mass, then if an object is internally heated, then it will lose "mass" with radiation.
 

Catastrophe

"Science begets knowledge, opinion ignorance.
Jzz, I think you are referring to Cat's link.

Your challenge to GR will require some powerful math to show how core densities can solve the old orbital puzzle, which was solved by GR to, eventually, everyone's satisfaction.

Newton had already shown how mass can be treated as a point location (center of gravity), which eliminates all density issues. This, I'm confident, is held to be true in GR.

But the math must be understandable even if it requires oversimplification as a precursor to the larger math model. Math that shows how an orbit can change due to internal activity (ie density changes) will be key, I suppose.

The only change I can imagine to an orbit due to internal behavior would come from the orbital shift in mass. Since energy is equated to mass, then if an object is internally heated, then it will lose "mass" with radiation.

Helio, you are correct in your confidence! Albeit with slight adjustment (for centre "space").


however, there are ways to define a similar concept based on the distribution of mass and the resulting spacetime curvature, which is often referred to as a "center of mass line" in more complex calculations related to extended bodies in general relativity.

Cat :)
 
Last edited:

Jzz

May 10, 2021
237
63
4,660
I am a degreed engineer and I don't understand it. How do we reconcile E=mc^2?
I think it has something to do with the fact that radio waves or in fact ANY electromagnetic waves had the ability to carry energy. So the question was how can a wave, which is a diffuse object, carry energy? Mixed up with all this was Madame Curie's discover of radio-activity. :D Hope that helps.
 
I understand that light as an EM wave has energy. I see the equivalence to the kinetic energy equation. It is missing the 1/2 though. That's odd. Anyway, somehow, someone can reduce energy units to a group of units that matches the units associated with mass and speed.
 
But light is not intermittent, it is continuous, at least in terms of energy flow, which is represented by the Poynting vector, and it stays constant in magnitude as it travels along. Even though light is represented by a sine wave of electric field, which does pass through zero, you must add the energy of the magnetic field sinusoid, which had its own energy and is at a maximum when the electric field is at a minimum.
 

Jzz

May 10, 2021
237
63
4,660
Your challenge to GR will require some powerful math to show how core densities can solve the old orbital puzzle, which was solved by GR to, eventually, everyone's satisfaction.
Helio, Thanks for your answer, even though I had wrongly attributed a quote as originating with you. As I look at the literature, it is apparent that there is a huge mass of data on this subject. But looking at a few articles on earth, which also has a partially liquid core, (although different from the Mercury core which has a large liquid silica component as well as an iron core) it seems that the semi-liquid core does play a large part in earth’s orbit. The tile of the article itself should serve to illustrate this: “Earth’s wobbly path gives clues to its core.”

The uniqueness of the science of physics lies in its openness to criticism. If a theory can be disproved, the discovery is (in contrast to other sciences) welcomed. Looked at in that light and not as someone wanting to substitute a new theory for an existing theory my post might make sense. The question is, do sufficient grounds exist for a doubt to be raised about an existing theory? It is in this spirit of enquiry that the OP was made. Although the premise made in the OP is literally dwarfed by the massive studies that have been conducted on similar problems, the results are far from conclusive and looking at the example of the earth itself, surely indicates scope for further discussion.
 
Both the magnetic and electric crossover is in phase with propagation. Check out any example. In my opinion that crossover does not qualify as intermittence. Intermittence requires a duration of absence.

That waveform is what one measures when EMR is detected. It is also the waveform that is used to generate propagation.

But it is not the waveform that is propagated. An intermittent saw-tooth wave is propagated. With a 50% duty cycle. Always emitted with that 50% DC. Allowing much more precise measurement of speed and distance when measured properly. Not used at present. Not detected at present. Two switched isolated antennas are needed. One for the duration of photon and one for the duration of absence. The duty cycle ratio. The true measurement of EM radiation. That ratio changes with changing displacement. In proportion.

That sawtooth ramp, that acceleration, is both a magnetic and electric ramp, transferring an EM field torque on the neutral/or charged, matter field. And that matter reacts to that stimulus via oscillation causing heat. And forming an EM sine wave. Light twerks matter. And the matter heats.

That sawtooth is a superposition of the E and M field. A handed array. And a variable density array. That ramps. An acceleration at a constant velocity. Repeated hammers. Repeated twerks.

Only a flux of intermittence has continuous flow. An average. An in phase portion forms a beam.

Just supposition based on electric tinker toys and magnetic erector sets.
 

Latest posts