Reading - A Brief History of Time
As my son said, "A Brief History of Time," by Stephen Hawking, "is dense." That is, it takes a lot of thinking. But the good thing about it is, it is written simply, without all the mathematical underpinnings which would make it indecipherable to most people. Stephen Hawking goes out of his way to express things like four light years as "twenty-three million million miles" instead of 23,000,000,000,000 or twenty-three trillion miles. He never goes above the word million, although sometimes he has to repeat it many times.
This book is actually a brief history of the theories that scientists have come up with to explain why the universe looks like it does. The book is slightly outdated, however. Even though it was updated in 1998, Hawking still has a preference for the eventual contraction of the universe. Actually, evidence from 1998 until now shows, not only is the universe expanding, but the expansion is accellerating. This accelleration of the expansion of the universe is not included in the book.
"A Brief History of Time," is well written, and fairly readable. If you have an interest in things like the theory of relativity, you will probably enjoy reading this book.
But let me suggest a slightly different theory. The following bit of science lecture is something that I cut out of the final drafts of my book, Life after Life. Maybe you'll find it entertaining. The fictional science teacher's name is Martin Frobish. And, if I hadn't cut it out of the book because it did nothing to advance the plot, he would have been seen as saying the following:
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"Remember that for the test. But now, related to the scientific process, I am going to tell you a story about physics that may change your world view. It won't hurt a bit, but maybe it will help you to see that there are still possibilities for change in the way people understand science."
"Think about light, also known as energy. Everything that you can see and hear and taste and smell and touch is made out of energy or light. As Albert Einstein said, 'E=M c-squared.' That is, energy or light, equals a measurable amount of mass, or matter. And we can convert energy into matter and vice versa. Not easily, but it has been done."
"Given, that every physical thing that we know of is made out of some form of light --- what do we know about light? Well, we know that light is very small, but not immeasurably small. And it is very fast, but not immeasurably fast. And it moves through time and space in three dimensions."
"So far, so good. This world-view is pretty much accepted by nearly every educated person on the earth today. Picture in your mind, then, a single photon of light flying through empty space. This photon will have a measurable dimension which has been called a wavelength, which determines the color of the light. And it will have a measurable dimension which we call an angle of polarization. But the interesting thing about light is, regardless of these properties, all photons appear to travel the same speed through empty space."
"Now here is where I want you to change your world-view. As our photon speeds through space, in each unit of time, what if each and every photon expanded by a fixed amount. Suppose, for example, that it doubles in size for each unit of time. Then, at the end of ten units of time it would be 1024 times its original size."
"But how would we measure it? If we had a ruler that was 1024 photon lengths long, at the beginning of the first unit of time our photon would measure one unit of length. But at the end of ten units of time, our ruler would have also expanded by 1024 lengths because all matter is made out of light, and every photon of light would have expanded 1024 times. Therefore, at the end of 10 units of time, our photon would still measure one unit of length in size. So, measuring photons directly doesn't really tell us whether or not all photons are expanding as they move through time."
"But just suppose, for the next few minutes, that all photons are expanding as they move through time. What are the consequences of such a thing happening?"
"First of all, gravity would not be a function of matter being attracted to other matter, it would be a function of ever-accelerating matter pushing out against other matter. Albert Einstein said it best when he said, 'gravity is acceleration.' If all light, and therefore all matter, is constantly expanding, then ordinary gravity is not a process of some mysterious and invisible field reaching out to pull everything toward a hypothetical center of the earth. Ordinary gravity is a process of every single photon and atom which makes up the earth, pushing out against each other to accelerate the surface of the earth as it moves outward through time."
"Einstein gave this example --- If we were inside of an elevator car, in the middle of empty space, we could measure the acceleration of our car if it were being towed or pushed through space by an accelerating rocket. But if our elevator car were sitting on the surface of a planet, we could never know whether the acceleration was due to the gravity of the planet, or the acceleration of a rocket through empty space. Remember, Einstein said, 'gravity is acceleration.'"
"Remember the story of Sir Isaac Newton, sitting under his apple tree? From his point of view, he is at rest, not moving. When an apple falls to the ground next to him, he hypothesizes a law of gravity reaching out and pulling the apple toward the earth. But his assumption was wrong. He was not at rest, he was moving. As anyone can clearly feel, we are all being pushed outward, being accelerated outward by the surface of the earth. Even the apple tree is being pushed upward. When the stem breaks, the apple goes into free-fall until the surface of the earth has been pushed out to meet it."
"So, how can we test this hypothesis? Well, if it were true, then every object --- regardless of weight, but discounting air resistance --- every object would fall at the same speed toward a planet. Things would only fall at a slower speed when the planet were a smaller size or mass. Remember how slowly things fell on the moon? The moon is smaller and lighter than earth. It has less acceleration."
If this hypothesis were true, then every planet or moon over a certain size would have a molten, liquid center. When men went to the moon, they left a seismometer on the surface to test the vibrations through the moon when the lunar module blasted off again. The registered vibrations were consistent with the moon having a small liquid core. It surprised a lot of people at the time."
"If this hypothesis were true, then planets would not necessarily have been formed out of molten rock, slowly cooling into a rock-hard solid mass. But they could have been formed by the accumulation of small cold chunks. The pressure of gravity would have melted the center, leaving us with plate tectonics as continents drifted into each other."
"If this hypothesis were true, then geothermal heat will be virtually inexhaustible. The hot-springs of Iceland have never gone cold. The geyser's of North America's Yellowstone park have been erupting faithfully for hundreds, or perhaps thousands, of years. If true, the earth will never stop having volcanoes."
"How can we test such a hypothesis? If it is true, there may be a measurable difference in the time it takes for the sun to rise or set. Sunrises should be faster, and sunsets should last longer because the earth would be expanding forward into the approaching light of a sunrise, and it would be expanding backward, away from (but expanding into) the receding light of a sunset."
"Is there a weakness in this hypothesis? Yes, of course. The weakness is the lack of 'action at a distance.' Action at a distance is real. We can take two magnets, and moving them close to each other, we can measure the force of attraction, or repulsion between them. We cannot explain the cause for it. We can only give it a name. We call it a magnetic field, and we can measure its effects. It is action at a distance."
"If we explain simple gravity, not as 'action at a distance,' but as the accelerating expansion of light and matter, then we have to explain how the tides work, and why everything has not just expanded into each other. What keeps everything apart? Here's where we have to bring in action at a distance."
"If the entire universe is expanding on an atomic or sub-atomic level, we will have to assume that part of the expansion happens in some dimension outside of our visible three dimensions. The unobserved expansion would physically affect nearby matter with a force that pushes things apart from each other. This could explain how moons continue to fail to fall into the planets they circle, and how tides happen to be pushed away on the side of the planet closest to the moon."
"This, of course, seems absurd to the classically trained scientist. But it is no more absurd than believing in an invisible force field that attracts everything together. Gravity, as an ever accelerating expansion of matter is actually a simpler explanation. Everyone can feel it. And it fits the evidence better. After all, the entire universe is not only expanding, but the expansion is accelerating."
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Think well,
Logan
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