To come full circle…it seems to me that to accept gravity as real you also have to accept “action-at-a-distance”(https://en.wikipedia.org/wiki/Action_at_a_distance). It is obvious that action-at-a-distance (other than to the most ardent believers) is a tenuous concept that has zero empirical evidence (http://www.newappsblog.com/2012/07/newtonian-gravity-as-as-action-at-a-distance-you-know-a-sympathetic-process.html) and instead relies upon metaphysical arguments and conjecture.
To claim that any object orbits due to the gravitational attraction of bodies is speculating and is attributing special, hidden and unverifiable qualities to matter. In essence, gravity cannot be proven since it can’t be shown to not exist. For example, I can solve the buoyancy of a balloon without the need to include gravity. Volume, differences in density and temperature will give an exact value for lift. However, someone could simply argue that since gravity is inherent within all objects (“the conspiring nature”), you don’t need to include it; therefore, I can give gravity any arbitrary value and the results will match (ie. the total amount of lift will be the same). Try it yourself – just solve a buoyancy equation but give gravity a value of 1 or ignore it altogether. If you think about it, how is terminal velocity, buoyancy and density any different than acceleration due to gravity (ignoring action-at-a-distance)?
In fact, all equations that have a gravity function can be removed without altering the real outcome. However, the only equations which will not work are objects in orbit that require action-at-a-distance. An orbiting body like the ISS requires a continuous change in direction. The change in direction involves a net zero force. So just like the schwarzschild radius can divide by zero (https://www.thunderbolts.info/thunderblogs/archives/guests08/061108_sjcrothers.htm) a change in direction requiring zero force requires a complete suspension of disbelief (https://www.reddit.com/r/askscience/comments/3be0zs/how_are_orbiting_objects_not_accelerating_due_to/). Honestly, how can something act on an external body with zero force? It doesn’t matter if you qualify it as a *net zero force* or not. The result is zero…meaning no force. This was the greatest achievement of Newton – to separate the relationship between force and motion. But can anyone really claim that this has any reality? To do that, you *have* to believe in action-at-a-distance *and* that a change in direction is possible *without* force. Other than orbiting bodies (which in themselves are not verifiable), is there any empirical evidence of this?
Many have convinced themselves of the validity of such an action because the implications are too devastating to consider – What if gravity is a false premise? But it’s impossible to prove a negative. One would then have to start questioning and challenging the supposed authorities on these matters. Most of science can still move ahead by removing gravity from their equations. However, one particular science cannot. I will let you guess which one that is. What would happen if an orbiting body is impossible? What does that say about the information that we are presented with everyday?
What if you started testing and thinking with your own eyes and mind? Ideas that were previously blocked from consideration might become viable. But this requires a person to recognize that they believe something as a matter of faith and not because it is self-evident or a testable hypothesis. We are all subject to articles of faith (even atheists). If a person doesn’t think that they are subject to those articles then woe to them. And to argue that the presence of the moon is proof of gravity merely reinforces the idea of that article of faith. The moon and its motions are not fully understood and anyone claiming they do understand it are being intellectually dishonest at best or deliberately misleading at worst.
This is a re-post of an article I wrote in reply to JimSmithInChiapas. He has been kind enough to respond to some of my ideas on gravity, centrifugal and centripetal force. Though he does not agree with my assessment of these forces, we continue to communicate in a respectful manner. Below is a recent reply to a comment he had on centripetal forces. Ultimately, I feel that the centripetal force has been fundamentally misapplied in spinning frames of reference. It is my contention that a single frame of reference for spinning body requires that for any object to be apart of that frame, it must be attached directly to that spinning body. This has massive (no pun intended) implications. You can read my argument below:
Jim…thank you for your reply. I initially wanted to clarify a slight misrepresentation in your article. My article is called “Does Gravity Make Sense?” not “does gravity exist?”. They are different concepts. I’m questioning how gravity is being represented by mainstream science today not that objects have mass or that they fall from the sky.
In any event, the example that I used provided a single frame of reference with respect to a spinning disk. I used a disk with a 10m radius that spins at 10 m/s with a person of 72kg on the outer rim. The person would experience 720N/kg of centrifugal force. I don’t think that is in question. I then go onto saying that unless the person holds onto the disk (via an attached handle of some kind), they would be flung from the disk at 720N/kg. Again, I don’t think that is in question either. The centripetal force is an inward force that requires the handle and the person to be attached to the disk at all times.
A more illustrative example would be the Olympic hammer throw. The athlete is holding onto a tether which is attached to heavy weight. The spinning motion of the athlete creates the centrifugal force which flings the weight outwards. The strength of the athlete keeps the hammer from leaving a circular orbit via a centripetal force. The inward force (centripetal) is provided by the athlete which is ‘balance’ by the centrifugal force. But all the spinning objects in that frame of reference are and must be attached together.
There is no empirical evidence of a centripetal force acting on a body that is not attached to the spinning body. How could it?
There are no real world examples of a free floating object being acted on by a centripetal force. You can mathematically present a centripetal force acting on an object but it is missing the real world necessity of being attached to or apart of the spinning object. The centripetal force is a function of a spinning object; it is not a separate force that can be applied to an object outside that frame of reference. To be part of that frame of reference, an object would, by necessity, need to be attached to the spinning object.
For example, the person in the disk example above, is not part of the frame of reference unless they hold onto the disk with sufficient force. They are literally removed from the frame via the centrifugal force.
Therefore, I would conclude that any object that is rotating around the earth must, by necessity, be attached to the earth to be part of that frame of reference for any object not attached is subject to the centrifugal force and will be removed from the frame.
If we take a real world example of a person of 72kg standing on the surface of the earth and if they are standing at the equator and if the earth is spinning at 1000miles/hr then they are subject to a centrifugal force of 2.2N/kg. If gravity is acting on the person with 9.8N/kg then a total force of 7.6N/kg is present. The centripetal force is not part of the frame of reference for that person as shown above.
As the mass of the object increases, the centrifugal force increases. Therefore, an object greater than ~330kg should become “weightless” on the surface of the earth. This is obviously not happening nor are people 22% lighter at the equator than they are at the north pole. Additionally, the person would not feel heavier if they grabbed hold of something attached to the earth.
What I’m showing is that there is a discrepancy between real world situations and the mathematical examples presented by modern science. At this juncture I can only conclude that the centripetal force is being improperly applied across multiple spinning frames of reference to account for the discrepancy and if that is the case then we cannot be in a spinning frame of reference (as shown above).
I was looking at some additional sites from NASA that try to explain the nature of gravity at certain altitudes. https://www.grc.nasa.gov/www/K-12/airplane/wteq.html
The final sentence of the explanation is “…But the high orbital speed, tangent to the surface of the earth, causes the fall towards the surface to be exactly matched by the curvature of the earth away from the shuttle. In essence, the shuttle is constantly falling all around the earth.”
As mentioned in my previous posts, the centripetal force only makes sense for something that is tethered to the spinning body (If you feel that the centripetal force *does* have special powers, please provide a clear empirical example that can be tested). Neither the space shuttle nor the ISS are tethered to the earth unless we grant the centripetal magical grappling abilities (see hammer throw). https://www.youtube.com/watch?v=KnHUAc20WEU As well, for the shuttle to be constantly “falling” but not actually falling downwards, a constant acceleration would need to be applied (ie. rockets) plus a continual adjustment of direction or the shuttle would fly off into space (see what happens when the hammer is released). Again, for apparent “weightlessness” in space, it would require objects to be falling at a rate of 9.8N/kg (or m/s/s) which would mean a constant counter-force of equal value would need to be applied or they would rapidly fall to earth. So the “floating” objects and people in space would need to be in a free fall all the time. This is obviously not the case since the ISS would have crashed to earth a long time ago. In essence the ISS is just like a airplane at a higher altitude and would require constant thrust to stay in “orbit”. If you turn off the engines of an airplane at 30,000 feet will it stay in “orbit” because “…the high orbital speed, tangent to the surface of the earth, causes the fall towards the surface to be exactly matched by the curvature of the earth away from the [airplane]? ” I don’t think any scientist would want to be in that airplane at 30,000 feet. It should be noted that the standard equation for centrifugal force for any object at the equator great than ~317kg would have a centrifugal force greater than gravity. Unless the centripetal force is magically grappling those objects, they should all start floating and since objects like elephants weigh ~4000-7000kg, they should all be floating thousands of miles above the earth.
If we grant the ISS a value of 3217N/kg (centrifugal force) due to its orbit around the earth (@ 17,150 miles/h & 4200 miles & ~331,000kg) – what force was initially used to get it to that speed?), then an equivalent (but opposite direction) for it must be present via the centripetal force. In order for a centripetal force to be present the object must be tethered to the earth. However, to obtain 3217N/kg, this would require the object to be traveling at a faster rate than the earth’s rate of spin. So an object that travels faster than the earth’s rate of spin *must* be under its own propulsion and not tethered to the earth. Since the ISS is traveling at such a high rate of speed and is not tethered to the earth, then it *must* be under its own propulsion and heading. This is plainly not the case. If the centripetal and centrifugal forces are equal but opposite directions, then we are left with 9.8N/kg (the force of gravity) on all objects.
In conclusion, if the centripetal force only applies to objects that are tethered to a spinning object (ie. Earth) then objects above the earth’s surface must be constantly under their own propulsion (like an airplane) to stay above the earth’s surface. In other words, the ISS should be falling out of the sky.