Gravity is not "attraction/reaction between two or more objects", it is not a 'force' at all. It is a curvature of spacetime.

[science.howstuffworks.com]

[livescience.com]

@FearlessFly Is NOT a force also an attraction or action of repulsion,etc so to speak?

@Triphid You might convince Isaac Newton, but not Einstein.

@FearlessFly And who, except them, is to say they were right or wrong, after all these 'Laws' of Science ARE really only accepted hypotheses are they not, there IS NO 'Users Manual' or 'Instructions Book' floating around in the Universe is there?
For example, the Moon orbits the Earth by both being 'captured' by the gravity of the Earth BUT it is also being drawn/repelled AWAY from the Earth by its motion (orbit) and its own gravity working slowly against that of the Earth.
Ergo, gravity can be both attraction and repulsion at the same time can it not, just as the North poles of two magnets repel each other?

@Triphid It is not just them. Are you not aware of all the scientists and experiments that convince (most of) us of what is right (and not) about their ideas ?
Magnetism IS A FORCE, gravity is a curvature of spacetime, not an attraction.
If those links I provided don't convince you, I wont' continue to attempt it.

@FearlessFly Oh so , according to you, when one falls from any height IT IS NOT the force of gravity being exerted upon them, IT is that they are 'falling' through " a curvature in spacetime."

@TheMiddleWay Yes, Gravity does cause a kind of warp/curvature in the space-time around the object ACCORDING to the Hypothesis/Theory that has been put forward.
And, in my opinion, that is kind of like saying that " When I flick on the switch to turn the light on the electrons miles away at the Power station all rush along the wires to make the light bulb glow."
Well, that is NOT how it works, the copper electrons in the wires NEVER change position as such, they merely gather the charge from Generators and pass that charge on from one to the next and so on, i.e. a PROVE electrical FACT not a theory/Hypothesis I you can understand the difference.
But electrical 'force' is NOT "due to the mediation of photons, etc," it IS the interaction between ELECTRONS and to some extent with the Protons in the nucleus of the atoms they orbit around whereas Photons are charged particles that emit light generated by entirely DIFFERENT methods to the generation of electricity.

@TheMiddleWay Yes, a Photon is a CHARGED particle of Light and emits Light as well.
And, as per my years and years as both an Amateur Radio Operator and a qualified Technician working on appliances such as televisions, radios, Stereophonic systems, etc, etc, plus designing AND build my OWN HIGH Gain Transceivers and Antennae, an ELECTRICAL Charge or force is the resultant of the excitation of the electrons surrounding-orbiting the atoms of a conductor such as copper wire for example and as such an excitation occurs it traverse from one electron shell to the next and so forth, whilst doing that it creates, also, a detectable EM field that radiates from the conductor, either horizontally, IF the conduct is placed in a HORIZONTALLY polarized position and in a horizontal wave pattern OR in 360 degree wave pattern IF the conduct is placed in the Vertically polarized position.
And as such, since we humans have had electricity grids for almost 100+years then this planet HAS been emitting into the Universe a steady EM signal ( i.e. Radio Signal) at a frequency of approximately 50Hz or 50 Cycles per Second and that signal travels through space at a velocity of approx. 300,000 Kilometres per Second, i.e, the Speed of Light itself.
The light emitted by a Photon covers the entire spectrum of light, from Infrared light through to Ultraviolet in case you were unaware, Infrared being at the 'slowest' end of the speed of light and Ultraviolet being at the 'fastest' end of the speed of light btw.
And, as any reasonable Grade 10 science student can and will tell you, an atom consists of a Nucleus containing mainly Protons and Neutrons PLUS from 1 to a number of Electron SHELLS around the Nucleus BUT NOT actually physically in contact with the Nucleus.

@Triphid pardon me for being pedantic, photons are both particles and waves . . .
[plus.maths.org]

@TheMiddleWay Yes, my recall of such has been a wee bit erroneous with such as time has passed by.
But, are not photons particles emitted/issued from a sources, the Sun, for example, in streams/beams?
If memory serves correct, photons can be deflected, reflected, absorbed, magnified, re-directed, etc, by the influence/influences of EXTERNAL means/forces, such as mirrors, magnifying lens, etc.
A prism, for example, creates the effect of a 'rainbow' by altering the frequency/frequencies of the photons/light particles as they pass through it BUT does not, detectably alter the wavelength of the of the light beam itself, hence 'red colouration' occurs because the original light is WHITE but contains all the colours of the spectrum within and red is the lowest frequency whereas ultraviolet is the highest frequency.
also, our eyes 'detect' colour because certain objects, gases, minerals, etc, absorb light and reflect only the part of the light spectrum that they cannot absorb, for example, we see green because a leaf absorbs the light and reflect the section of the spectrum that travels at the frequency we associate as being green.
Though, I might add, I may have, due to the rigors of age upon memory, put the absorption-reflect theory arse about forth and, for which, I stand corrected.

@TheMiddleWay Thank you, then my memory is still working reasonable well, that IS good news to me.

Not only just leaving it to science BUT the entire human species working together as one would be, imho, the optimum.

@Triphid Hi, Tri. (poetry) I think we will continue being human.

@yvilletom OR, maybe we will continue to evolve IF we can rectify the damage we have done to the climate and environment in the meantime that is and who knows for certain what the evolutionary process holds in store for humans.

I'm not sure that's true. Pretty sure bats and birds have been known about for more than 100 years. There may have been people who thought the technical challenge was too great but to think there was a law of physics that prevented heaver that air flight would require some serious ignorance about the natural world.

@MattHardy Obviously I meant airplanes, also in context before the Ohio boys.

@MattHardy Avionics is all about Aerodynamics, i.e. lift, thrust and weight versus gravity and friction to put it in fairly simple terms.
Humans, for one example, are NOT aerodynamically shaped via the evolutionary processes, sadly, BUT through thinking OUTSIDE of the box/s, in just over a century, thanks to those who decided to NOT remain held down by the 'inside the box thinking ideologies' humans can now fly across continents and oceans in aircraft that were once thought impossible just as it was once widely 'claimed' and adhered to that " No human being could EVER physically run the distance of ONE mile in less than 4 minutes'" well that 'Law' has gone down the tubes as well.
These so-called 'Laws' of Science, Physics and the Universe, etc, are there to be bent or broken, they ARE NOT inscribed in stone, they are, at best, merely hypotheses.

@IamNobody I'm not sure why that need pointing out. Obviously you meant airplanes. And obviously nodody before the Wright Brothers thought that airplanes were against the laws of physics. Because obviously.animals and machines both operate under the same laws of physics. They may have had many reasons for suggesting that airplanes were impossible but them violating the laws of physics should not have been one of them. I bet you can't source any example of someone making that claim.

@Triphid you may well be the first person in history to describe these as laws of science.

@MattHardy Gee dude chill.... Using your logic, since you said bats and birds, then I should have said that you are wrong too because there were also flys, bees, mosquitoes, etc etc etc

@MattHardy Well they ARE claimed to be the 'Laws' of the Sciences of Physics etc, etc are they NOT?
They WERE devised by humans in ATTEMPTS to EXPLAIN, within the bounds of LIMITED understandings at the times, how they THOUGHT (Hypothesised) things worked and behaved were they not?

@MattHardy, @IamNobody Yes, and according to these self-same 'Laws' of Physics it was clearly stated that " According to the Laws of Physics and Aero-dynamics, etc, given the wingspan, weight, configuration, etc, the common Bumble Bee/Honey Bee should NOT be able to fly," but, shock and horror, they do fly.
Ooops, didn't anyone ever bother to tell Nature and evolution about that one?

@Triphid No it wasn't a law of physics which said bumble bee's can't fly. It was a back of the enevelope calculation that evidently used invalid assumptions about the method of flight. [snopes.com]

@Triphid, Flys bees and mosquities would be additional evidence proving that powered heavier than flight does not violate the laws of physics. It doesn't prove me wrong it proves me right. You do seem rather muddled about this. There is a difference between a belief and a law of physics. Overturning a belief is nowhere near as momentous as overturning a law or physics. I agree that there were people who believed that humans would never fly. I don't agree that there were people who claimed it was against the laws of physics. Now you could graciously acknowledge the distinction or you could prove me wrong by finding a quote that stated that heavier than air flight was against the laws of physics. So for example were you to be trying to demonstrate the there were prominent scientists who believe aeroplanes to be impossible you could provide this link. [xaprb.com] However if you understand the distinction between stating a belief which may be based on a variety of different factors and stating that an experiment violates a law of physics then you'll see that none of these quotes mention any such law in support of their belief. No law of physics was rewritten in deference to the wright brothers. Not like the law of conservation of momentum would need to be revised if this experiment works or how Newton's laws of gravity were refined by Einstein.

@MattHardy Yes, BUT as I stated earlier and re-state here as well, These so-called Laws are the inventions, for want of a better term, of MAN are they mot and based solely upon the OBSERVATIONS of Man with his, thus far, VERY limited scope of both Observation and Comprehension of the Immense Universe that surrounds this tiny little chunk of rock, water, etc, that orbits but one solar body amongst literally Billions.
The human mind NEEDS to be able to rationalize EVERYTHING and Anything, that IS how we are SADLY, BUT who is to say for absolute CERTAINTY that that rationality exists or has ever existed in the Universe elsewhere?
I, for one, have always been a 'think outside the box' kind of person and it HAS gotten me both into difficulties and helped me to resolve many a situation in my life-time and I shall remain a 'think outside of the box person until my dying breath just as have others before me and, hopefully, after me as well, for it IS and has been those Thinkers who have driven the wheels of Human Advancement since time immemorial.

@Triphid no disagreement there. Laws of phyisics do get revised. Just far less often than other beliefs. It may well happen here. My objection here is to you and @IamNobody trivialising the magnitude of the event if that happens by describing as merely like the development of heavier than air flight proving wrong a few blowhard nay sayers. And suggesting that heavier than air flight was ever described as against the Laws of Phyiscs. It wasn't, and if you don't know it now, then that doesn't reflect very well on you and if you can't then admit that you were wrong... I feel sorry for you.

@MattHardy I know that the 'heavier than air' was NOT a part of the Laws of Physics, I was using it an example of how wrong the old school was with the Laws of Aerodynamics though.
However, are NOT actual Physics also, in some perhaps small way, a part of Aerodynamics as well?

@Triphid When you say "Laws of Aerodynamics" I'm not sure what you mean. Can you give an example? Bonus points if you can provide an equation.

@Triphid and to agree on one point, yes Aerodynics is certainly a branch of physics.

@MattHardy Perhaps, on hindsight, I should have said "Rules Governing Aerodynamics" rather than 'Laws.'
Yet, we have seen even those 'Rules' being somewhat bent and even broken in the few decades or so, have we not?
I remeber reading, as a Teenager, where Werner Von Braun once stated clearly that " creating a craft that could be launched from the surface of the planet into space and returned to earth in ONE complete piece was a 'pipe-dream' and an impossibility."
Oooops, methinks someone FORGOT to inform the designers of the Space Shuttle of the prophesy.