Must we have evidence to know the truth?
Yes, in this day and age evidence is more important than it ever was before. There are so many lies on the internet and on TV and because of this, you can’t trust a lot of the stuff that you hear, We have a president who lies everyday and not only do people swallow all of his bullshit, they applaud it like idiots.
How much control does a person have over their life?
I don’t believe in fate or destiny, so everyone has some control over how they live their lives. If life hands you lemons, then make lemonade, but there is such a thing as luck and because of that, some people will face less tragedies in their lives. No one ever said that life was going to be easy, as you are born, you have to pay taxes and everyone ends up dying in the end. Some things you can’t control, so you try to make the best of these situations.
What is gravity and how does it work?
Understanding gravity is complicated and many people are able to know that it exists, but they will bever know how it works. Our knowledge of gravity has changed over time going back to the ancient Greeks, being improved by Newton and rewritten by Einstein. Galileo reasoned that a projectile shot from a cannon is not influenced by just one motion, because it is composed of two, one being the motion that acts vertically which is called the force of gravity, and this motion pulls the projectile down toward the Earth by the times-squared law. Giovanni Battista Baliani described the correct laws of gravity, movement on inclined planes and the movements of pendulums and he enunciated the law of acceleration of a body and to distinguish between mass and weight. Torricelli determined a “universal theorem”, which would allow someone to find the center of gravity of any figure. Huygens formulated a theory for finding a curve on which an object falling under gravity will reach the bottom in the same amount of time, no matter from where it starts.
Sir Isaac Newton, the man who sat under an apple tree and had his “eureka” moment concerning gravity, spent a lot of his time trying to figure out the slope of a curve that was constantly varying, when he was formulating his Laws of Motion. Newton was the first person to wonder if gravity extended beyond the Earth and perhaps this was the force that was keeping our Moon in orbit around our planet. With Newton, gravity became a field of attraction, instead of being a vague phenomenon that nobody understood. Before Newton, people understood that if they were to jump up into the air, that gravity would pull them back down, but they did not know how it worked, so they just classified gravity as a law of nature. Because of Newton, we know that all objects have a force that attracts them towards each other, which is called gravity.
Einstein discovered that the usual concepts of physics embodied in Newton’s laws, simply didn’t work at very high speeds or under conditions of extreme gravity or in many other situations, so he came up with his General Relativity (GR) theory, which is considered to be the most beautiful physical theory ever invented. The mathematics involved in general relativity are quite complicated and it involves curved space geometry that is not easy to comprehend. Gravity is a force like electromagnetism, and the weak and strong nuclear forces. Einstein’s theory of General Relativity describes the force of gravity, and it gives us black holes, while discussing the expansion of the universe, and the potential for time travel. Albert Einstein turned things upside down when he suggested that matter and energy warp spacetime, producing the phenomenon we call gravity and he predicted that light would be bent by gravity. Einstein spent most of his life trying to make things simpler, to find laws of physics more general than known before and to unite gravity with electromagnetism. Because of Einstein, gravity can be described as motion caused in curved spacetime.
Richard Feynman took an untraditional non-geometric approach to gravitation and general relativity based on the underlying quantum aspects of gravity and he offered his insights into gravity and its application to cosmology, superstars, wormholes, and gravitational waves. Stephen Hawking predicted that gravitational black holes would emit thermal radiation and decay, which is known as Hawking radiation and this helped in the development of a quantum theory of gravity.
We still don’t know if gravity is strictly an attractive force, because dark energy seems to be accelerating the expansion of the universe, and this suggests that gravity may work both ways. We have not come up with a “theory of everything” yet, and this is mostly because we really don’t totally understand gravity yet.
Can a person be happy if they have never experienced sadness? How about vice versa?
Is there light without dark? This dichotomy is much deeper than trying to understand gravity. I guess that if a person is born without a brain and they are happy, that it is possible to be happy without ever experiencing any sadness in their lives. If a person is happy all the time, are they really happy? The village idiot would be an unrealistically optimistic or naïve individual and although they may look happy 24 hours a day and seven days a week, because they are smiling and grinning all the time, this permanent happiness is a mental dysfunction.
Melanie says that we should share something that we are grateful about after answering her questions and I am grateful that I can work on my computer without using my glasses anymore.
Written for Melanie’s sparksfromacombustiblemind’s Share Your World.