If there’s anyone who can, please let me know if the similarities between these two formulas imply a relationship between gravity and electrical attraction or hint at a unified theory, or if it’s just a coincidence or a consequence of something else.
The relation between them is that they’re both forces that scale with the inverse square of the distance between the objects. Any force that scales with the inverse square of distance has pretty much the same general form.
Another similarity is that both are incomplete, first approximations that describe their respective forces. The more complete versions are Maxwell’s laws for electromagnetism and General Relativity for gravity.
There’s some relation in that they both act on fields, but the things that affect those fields are very different (higgs bosons and electrons respectively) and the relationship between all that for an ‘unified theory’ is a topic of much research. IANAP though (not a physicist)
There is one thing particularly interesting, and that is that the inverse square laws appears again. It appears in the electrical laws for instance.
That is electricity also exerts forces inverse to the square of distance with charges. One thinks perhaps inverse square distance has some deep significance, maybe gravity and electricity are different aspects of the same thing
…
Today our theory of physics, laws of physics are a multitude of different parts and pieces that don’t fit together very well. We don’t understand the one in terms of the other. We don’t have one structure that it’s all deduced we have several pieces that don’t quite fit yet.
And that’s the reason in these lectures instead of telling you what the law of physics is I talk about the things that’s common in the various laws because we don’t understand the connection between them.
But what’s very strange is that there is certain things that’s the same in both
Electromagnetism and gravity are both mediated by massless bosons; photons and gravitons respectively. This is why both forces follow the inverse square law.
I don’t think there’s any evidence for gravitons yet, and gravity hasn’t been quantized. I’d say it’s this similarity that’s the best argument of quantum gravity, not the other way around.
Fair. The masslessness of the bosons that should mediate gravity, along with them being spin-2, can however be deduced from the properties of gravitational waves.
We know that gravity is a wave that travels at the speed of light, this has been experimentally measured many times. If it is also quantized (a very reasonable symptom hypothesis since everything else that we’ve ever seen is) then by definition there are particles that carry gravity.
If gravity is continuous then we would end up with something like the ultraviolet catastrophe but for gravity.
Hmm, I hadn’t considered an “ultragravity catastrophe”. I wonder if this could accout for dark energy or the supposed inflatons? Probably not, the catastrophe suggests infinite energy, not just lots of energy, eh?
The ultraviolet catastrophe was averted due to the discreet nature of electrons though, and I don’t recall gravity behaving as a blackbody radiator anyway. Would this come into effect at horizons?
Sorry, I think I came off as too confident in my previous comment. I’m quite sure about my first paragraph but the rest is just speculation from an amateur.
If I would risk speculating even further though, there’s some similarity in the sense that infinities indicate a problem. In the ultraviolet catastrophe the infinity arises from the energy of arbitrarily short EM wavelengths. With gravity it arises in the density of black holes. It seems unreasonable that it would actually be infinite, and it’s possible that quantization of gravity plays a part in preventing that from happening.
It’s really simple, they are both radial fields with a 1/r potential, thus a 1/r² force.
Newtonian gravity is just a weak field approximation of general relativity, where you have very different equations, for example Einsteins field equations…
One electric charge creates an electric field, and another charge will interact with it, but the motion itself still depends on the mass of the second charge.
Matter instead curves spacetime itself, and the curved spacetime tells matter how to move.
Source: MS in physics.
Doubtful but interesting thinking. It’s actually a rather simple equation that explains how two equally weighted forces affect one another over distance. The numerator expresses that both forces carry equal weight in the interaction (if they are both the same kind of force, eg gravity or electromagnetism, this makes sense) and they are constructive interactions (both add to the intensity of the interaction) hence multiplying one by the other. The denominator just indicates that the distance between the two things exponentially degrades the force at a power of 2, since the force is spreading out in 2 dimensions (imagine a cone starting at one point and extending to the second, so that when you reach the second point the force is spread across the cross section of that cone, but the only part of the force affecting that second point is the part that touches it).
If there’s anyone who can, please let me know if the similarities between these two formulas imply a relationship between gravity and electrical attraction or hint at a unified theory, or if it’s just a coincidence or a consequence of something else.
The relation between them is that they’re both forces that scale with the inverse square of the distance between the objects. Any force that scales with the inverse square of distance has pretty much the same general form.
Another similarity is that both are incomplete, first approximations that describe their respective forces. The more complete versions are Maxwell’s laws for electromagnetism and General Relativity for gravity.
There’s some relation in that they both act on fields, but the things that affect those fields are very different (higgs bosons and electrons respectively) and the relationship between all that for an ‘unified theory’ is a topic of much research. IANAP though (not a physicist)
Are higgs bosons supposed to be gravitons? I think you’re confused about how some particles aquire some of their mass, and how all mass behaves.
The most accepted theory among physicists is that “shit’s crazy, yo”.
Richard Feynman and 45:48 https://youtu.be/-kFOXP026eE?si=hAIvDhWVGxMOvEi1
Always upvote Feynman. Got me through some tough times in undergrad.
Here is an alternative Piped link(s):
https://piped.video/-kFOXP026eE?si=hAIvDhWVGxMOvEi1
Piped is a privacy-respecting open-source alternative frontend to YouTube.
I’m open-source; check me out at GitHub.
Electromagnetism and gravity are both mediated by massless bosons; photons and gravitons respectively. This is why both forces follow the inverse square law.
I don’t think there’s any evidence for gravitons yet, and gravity hasn’t been quantized. I’d say it’s this similarity that’s the best argument of quantum gravity, not the other way around.
Fair. The masslessness of the bosons that should mediate gravity, along with them being spin-2, can however be deduced from the properties of gravitational waves.
We know that gravity is a wave that travels at the speed of light, this has been experimentally measured many times. If it is also quantized (a very reasonable
symptomhypothesis since everything else that we’ve ever seen is) then by definition there are particles that carry gravity.If gravity is continuous then we would end up with something like the ultraviolet catastrophe but for gravity.
Hmm, I hadn’t considered an “ultragravity catastrophe”. I wonder if this could accout for dark energy or the supposed inflatons? Probably not, the catastrophe suggests infinite energy, not just lots of energy, eh?
The ultraviolet catastrophe was averted due to the discreet nature of electrons though, and I don’t recall gravity behaving as a blackbody radiator anyway. Would this come into effect at horizons?
Sorry, I think I came off as too confident in my previous comment. I’m quite sure about my first paragraph but the rest is just speculation from an amateur.
If I would risk speculating even further though, there’s some similarity in the sense that infinities indicate a problem. In the ultraviolet catastrophe the infinity arises from the energy of arbitrarily short EM wavelengths. With gravity it arises in the density of black holes. It seems unreasonable that it would actually be infinite, and it’s possible that quantization of gravity plays a part in preventing that from happening.
Why do I feel like I’ve been insulted
It’s really simple, they are both radial fields with a 1/r potential, thus a 1/r² force. Newtonian gravity is just a weak field approximation of general relativity, where you have very different equations, for example Einsteins field equations… One electric charge creates an electric field, and another charge will interact with it, but the motion itself still depends on the mass of the second charge. Matter instead curves spacetime itself, and the curved spacetime tells matter how to move. Source: MS in physics.
Doubtful but interesting thinking. It’s actually a rather simple equation that explains how two equally weighted forces affect one another over distance. The numerator expresses that both forces carry equal weight in the interaction (if they are both the same kind of force, eg gravity or electromagnetism, this makes sense) and they are constructive interactions (both add to the intensity of the interaction) hence multiplying one by the other. The denominator just indicates that the distance between the two things exponentially degrades the force at a power of 2, since the force is spreading out in 2 dimensions (imagine a cone starting at one point and extending to the second, so that when you reach the second point the force is spread across the cross section of that cone, but the only part of the force affecting that second point is the part that touches it).