Resolved - The earth is spherical

I congratulate lannan13 for arguing so well considering the difficulty of his stance on the resolution. Nonetheless I do not believe he actually proves that the earth is not spherical. Flat-earth theory I will argue that this theory is flawed. My opponent's image appears to explain how the sun and moon circle above the earth, thus creating what we know as day and night. However, the fundamental problem with this theory is that the sun's light is not focused like a spotlight is. The sun's light is radial (1)(it is emitted in all directions at equal intensity) and so there would be no reason why the sun's light would not reach all areas on the disc-world at all times. Con makes the following statement: 'If we use the Corpurnicus model we can see that the Earth is indeed the center of the Universe.' But Copernicus actually promoted a heliocentric view of the solar system, he never said that the earth was the centre of the universe. (2) The next argument presented by Con is that the earth would appear flat relative to cosmic rays that are travelling at the speed of light. However, this debate is over the shape of the earth in actual geometric reality, not whether it appears to be flat from the perspective of a relativistic particle. That logic would mean that, just because I put on red-tinted glasses, everything is actually red. Obviously this is incorrect. Gravity My opponent makes the rather extreme claim that gravity, as a force, does not exist. Instead, gravitation exists. The problem with this is that gravity and gravitation are mutually inclusive. The gravitational field (which is what Con appears to mean when he says 'gravity') scientifically entails that a gravitational force will be exerted if a mass enters the field (otherwise it wouldn't be a gravitational field)(3). Likewise, a gravitational force cannot exist without a gravitational field (4). My opponent then explains that the force we feel that brings us 'down to earth' is not gravity; instead, the earth is accelerating upwards at a speed of 9.88 ms-1 and therefore, according to Newton's 3rd law, we exert a downward force on the earth that 'roots' us to the ground. However, according to Newton's second law (F=ma)(5), the earth can only be accelerating upwards if there is a resultant force being exerted on the earth from directly above us. But what could this force be? We see no evidence of a force accelerating the earth upwards, nor any conceivable reason why it is being accelerated upwards. Furthermore, the evidence for the existence of gravity is not just limited to earth. On the moon, we have observed a gravitational force/field by dropping hammers and feathers (6). We know the moon is spherical so this 'down' force cannot be created by upward acceleration like my opponent claims is the case with the earth. We have landed at many different points on the moon (7)- yet if the appearance of gravity is merely the result of an upward acceleration, then the force on the hammers/feathers would be different if dropped at different parts of the moon. But this has not been found to be the case. My opponent's last point about how the gravitational force is towards the centre (the north pole) does not actually prove anything. All it does is say 'if the earth is flat, this is how it would work'. But it does not actually provide any evidence that the earth IS actually flat. Yet again, a gravitational force cannot exist without a gravitational field (because all non-contact forces require a field)(3). So to talk about a gravitational force, having previously denied the existence of a gravitational field, is incoherent. I'll pass this debate back to you now! (1) http://media.giphy.com... (2) http://www.biography.com... (3) http://en.wikipedia.org...(physics) (4) http://www.s-cool.co.uk... (5) http://www.physicsclassroom.com... (6) http://www.cnet.com... (7) http://en.wikipedia.org...