B Why can't gravity be just a form of magnetic attraction?

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Gravity cannot be equated to magnetic attraction due to fundamental differences in their nature and behavior. While both forces exhibit an inverse square law under certain conditions, gravitational forces are always attractive and independent of charge, unlike electromagnetic forces. Gravitational fields respond differently to moving sources, and gravitational waves differ mathematically from electromagnetic waves. The concept of monopoles applies to gravity, while magnetic fields lack monopole solutions, further distinguishing the two forces. Overall, gravity operates under principles that are distinct from those governing electromagnetic interactions.
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Based on the photo electric effect. Maybe its perception that is the problem? Charge doesn't travel through a vaccuum. Electro magntic waves alway carry photons. Photons can make charge. Charge creates magnetism? Would explain why Coulumbs equation is the same as the one for gravity but on a much, much bigger scale.
 
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mamba76 said:
Based on the photo electric effect. Maybe its perception that is the problem? Charge doesn't travel through a vaccuum. Electro magntic waves alway carry photons. Photons can make charge. Charge creates magnetism? Would explain why Coulumbs equation is the same as the one for gravity but on a much, much bigger scale.
Although they both obey a similar-looking inverse square law in one particular case (nothing is moving) there are many differences:
- gravitational forces are always attractive and independent of the electric charge present.
- gravitational fields change differently than electromagnetic fields when the source is moving (Google for “retarded potential”).
- gravitational waves are mathematically different than electromagnetic waves (Google for “gravitational wave quadrupole moment”)
- gravity doesn’t really follow an inverse square law; the Newtonian ##1/r^2## is an approximation that breaks down in strong gravitational fields (Google for “Mercury anomalous precession”)

Probably some more, but this will do for a start
 
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In addition to the correct points mentioned by @Nugatory one huge difference that is specific to magnetic fields instead of electric fields is that magnetic fields have no monopole solution, only a dipole solution at lowest order. The gravitational sources we observe around us are all approximately monopolar sources. A monopole source has a ##1/r^2## field, but a dipole source has a ##1/r^3## field. There is no way to get Kepler's law from dipoles.

Gravity is not a magnetic interaction. It has nothing to do with perception or the photo electric effect or anything else you mentioned.
 
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Nugatory said:
Although they both obey a similar-looking inverse square law in one particular case (nothing is moving) there are many differences:
- gravitational forces are always attractive and independent of the electric charge present.
- gravitational fields change differently than electromagnetic fields when the source is moving (Google for “retarded potential”).
- gravitational waves are mathematically different than electromagnetic waves (Google for “gravitational wave quadrupole moment”)
- gravity doesn’t really follow an inverse square law; the Newtonian ##1/r^2## is an approximation that breaks down in strong gravitational fields (Google for “Mercury anomalous precession”)

Probably some more, but this will do for a start
Would the 1/r^2 thing never breakdown with point like sources? Is the distribution of matter what confounds it?
 
synthesizers said:
Would the 1/r^2 thing never breakdown with point like sources? Is the distribution of matter what confounds it?
The ##1/r^2## rule for electrical fields is exact as long as ##r## is non-zero, although we will have to use the integral form of that rule for the most charge distributions. In the special case of a spherically symmetric charge distribution (which includes point sources) the integral form reduces to the familiar Coulomb’s law.

The infinity that appears when we set ##r=0## is just telling us that that case is unphysical - the idealization of a point charge with a definite position breaks down at small distances so ##r## is no longer meaningful.
 
Update -- after a bit of cleanup this thread will remain closed. LOL
 
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