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Time and Relativity: Is the Creator Hypothesis Necessary?
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Time and Relativity: Is the Creator Hypothesis Necessary? Concepts of Einstein’s theories of relativity create confounding, counter-intuitive concepts with which people struggle when attempting some level of understanding. I think the one question I get more often than any other when the subject of relativity comes up involves the question of adding velocities. Suppose you are in a spaceship traveling very near the speed of light: Let’s say for the sake of argument, you are traveling at only 100 mph less than light speed . You grow angry at one of your shipmates, and fire a pistol at him as he is standing near the front of the ship. Wouldn’t the<b> bullet </font></b>have to be traveling faster than light after it is fired? After all, if you fire a pistol out of a moving car, the<b> bullet </font></b>benefits from the forward momentum of the car. Similarly, when we launch planetary probes, we launch them from Florida in an easterly direction to take advantage of the Earth’s approximate rotational velocity of 1000 mph. Wouldn’t the<b> bullet </font></b>aboard the spaceship do the same, if fired in the direction of motion? Doesn’t violate a fundamental premise of relativity, nothing can faster than light? The answer is, no, for 2 basic reasons. First, we note an issue doesn’t really answer the question, but is worth discussing. Nothing in Einstein’s theories of relativity suggest that traveling faster than light isn’t possible. What Einstein told us is, no massive object can move AT the speed of light. As a massive object accelerates, a certain portion of the energy that is going into accelerating the object is increasing its mass. The closer you get to light speed, the more massive the object becomes. By the time you reach the speed of light, the object would become infinitely massive and infinite energy would be required to continue to propel infinite mass. Since both infinite mass and infinite energy can’t exist in the same place and time in the same universe, you can’t travel at the speed of light. In order to travel faster than light, you would have to accelerate through the speed of light at some point. So while Einstein didn’t specifically prohibit faster than light travel , it is a bit difficult to figure out how you could pull it off. Second, and more to the point, we come to the entire matter of frames of reference. If you are inside the spaceship, you more or less perceive yourself as standing still as space races past you at very near light speed. You fire your<b> bullet </font></b>and it travels the distance between you and your unfortunate victim at the typical speed of a<b> bullet. </font></b>In other words, everything on the spaceship appears to happen exactly the same as it would if you committed your horrifying act of homicide on the Earth. But suppose a stationary observer outside of the spaceship could watch the same incident occur. How would an outside witness see the events unfold? Well, things would look a lot different. First of all, a spaceship traveling close to the speed of light would be foreshortened in the direction of motion. So the outside observer would see you and your victim standing much closer together, so the<b> bullet </font></b>has a considerably shorter distance to traverse. Further, for the occupants inside the spaceship, time is traveling slower from the perspective of the outside observer because the spaceship traveling near the speed of light is vastly more massive. So everything inside appears to be happening in slow motion. The consequence of the foreshortening and slower moving time means that the<b> bullet </font></b>is still traveling well below the speed of light for all observers and relativity is not violated. The matter of the relative nature of the passage of time is the principle one I wish to address in this context, because it has profound implications, ultimately for how we should view the creation of the universe. As you sit in your living room, or wherever you may be reading this piece and believe me, is a matter upon which I have no real interest in speculating deeply, time is passing at a familiar rate . The seconds tick away as they always have. The passage of 60 of them define a minute. When 60 of those minutes pass , we note the passage of an hour. A day is defined 24 of those hours and so on. When we are doing something we enjoy, time can seem to fly by rapidly. but by contrast, tedious tasks almost seem to slow the passage of time. Einstein once quipped sitting on a hot stove for a second can seem like an hour, while an hour in the company of a beautiful woman can seem to pass in minutes. , that he explained, is relativity. But the passage of time really is relative. If you have an acquaintance aboard the International Space Station, time is actually passing slightly more rapidly for them while they are living aboard the station than it is for you over the same period. This is because you are closer to the center of the Earth, in other words, closer to a point source of gravity. The astronauts aboard I.S.S. are in micro-gravity, thus their clocks are moving more rapidly. This is not a theoretical concept. Not only is it true and measurable, it has significant effects on your everyday life which you may have never considered. Most of you probably have a smartphone with a G.P.S. application, or perhaps some sort of G.P.S. device in your automobile. G.P.S. stands for Global Positioning System. Currently, there are 24 satellites in Earth orbit that constitute the system. They orbit the Earth at an altitude of about ,twelve thousand miles up, about half way to geostationary orbit. In other words, they don’t stay in the same place with respect to the ground below, but all of them maintain their relative positions with respect to each other. Wherever you are on the Earth at any given time, there are always 8 satellites somewhere above your present horizon. It takes 4 of these satellites to determine your present position on the planet, and they can locate you to within about 9 inches. Your GPS receiver seeks out the nearest satellite. It basically defines your position on the surface of the Earth by timing the signal from your receiver, and offers that your present position is a point somewhere on a very large circle which can be drawn out as if the satellite is the top of a compass and the distance to you is the point of the pencil. Then your receiver contacts the second closest satellite, which also communicates with the first one. The 2 satellites now have determined you are at one of 2 points along the original circle. Your receiver then contacts the third satellite, which eliminates one of those 2 points, pinpointing your current position on the surface of the Earth. However, you may not be on the surface of the Earth, or at least not at sea level. Therefore, the 4th satellite determines your altitude above sea level. In this way, your precise position is determined. The 4 satellites also cross check each other. This is necessary because you may be moving, and it also eliminates error, which is critical. All of these communications are happening at the speed of light. An error of a thousandth of a second by any one of the satellites would result in a one hundred eighty six mile error by the system. So it is a constant system of measurement and verification. Our GPS satellites have the most precise atomic clocks we are able to build. But they are in orbit and as we have established, clocks in orbit move more rapidly than clocks on the ground. Therefore, the satellites must constantly remain in communications with equally accurate Earth based clocks for constant re-calibration. If these updates were not done, the effects of relativistic time dilation would throw off the information provided GPS satellites about 6 miles day. If you are on a navy ship launching a cruise missile at an enemy target, a 6 mile miss is obviously a rather unacceptable and potentially disastrous outcome. So, we have established the time dilation aspects of relativity are measurable fact. Let’s consider now, the extreme case; black holes. But first, we will explore the ultimate fate of our sun. Our sun shines by virtue of the process of hydrogen fusion. Hydrogen atoms fuse together into helium atoms. This process releases energy partially in the form of photons and heat. The existence of the sun, or any star is a long term battle between expansion from internally generated heat and collapse from the enormous mass which generates gravity. The heat energy from fusion counterbalances the inward, collapsing pressure of gravity. Helium is heavier than hydrogen and sinks toward the center. Helium atoms fuse into heavier elements like neon, oxygen and carbon. Further fusion occurs until iron atoms are fused, which collect in the center of the sun. The process of iron fusion produces no energy. Some 5 billion years from now, the sun will have exhausted most of its hydrogen and helium and the core will contain a huge amount of iron. Gravity will begin to win the 10 billion year old battle with internal heat, no longer generated in sufficient amounts by the largely iron core, and the sun will begin to collapse. But this will bring the remaining hydrogen atoms (and other atoms lighter than iron) into close proximity and furious fusion reactions will resume. Heat launches its counterattack causing the sun to bloat up into a gigantic red giant star. Mercury, Venus and perhaps the Earth will be consumed this enormous giant. But it is the last stand for heat energy. Almost all of the remaining hydrogen and helium will comparatively quickly fuse into heavier elements. The collapse will begin once again. For a star the size of the sun, the collapse will continue until electrons come into close proximity, permitting the weak nuclear force to overcome the collapse. (This is something of an oversimplification to avoid a rather complex discussion of physics. The actual process of halting the collapse is electron degeneracy pressure.) The result is a dense, white dwarf star. A teaspoon of material from this white dwarf would weigh in the neighborhood of fifteen tons. For a star a few times more massive than the sun, the process causes the sun to bloat into a red giant is replaced by an enormous explosion called a supernova, which releases a large part of its mass and importantly, heavy atoms like oxygen and carbon and even heavier atoms into space. But once the collapse of the remaining mass begins, the weak nuclear force can not halt the collapse. Now, elementary particles are squashed out of existence. Only a sort of crushed neutron soup can halt the star’s collapse and it is saved by the strong nuclear force. (Again, I am simplifying here to sidestep a detailed explanation of neutron degeneracy pressure.) We are left with a neutron star, a body so dense a teaspoon of material would weigh 10 million tons. A star once a few times larger than our sun is now compressed into a sphere perhaps miles across and spinning at a rate of hundreds of times second. But a star 10 or times or more massive than our sun can’t be saved the strong nuclear force. There is no force in nature capable of halting this collapse. All of the star’s previous mass is effectively crushed out of existence, as least as we define it the laws of physics we understand. All is left behind is a tiny singularity; all the gravity of the star with no mass. The laws of physics in our universe no longer operate beyond the event horizon of a black hole. Beyond the event horizon, the black hole’s gravity is so intense even light cannot escape. It is bent back towards the singularity. Suppose we could into one, and escape the obvious problems of entering into a gravitational field this profound. Gravitational attraction declines as the inverse square of the distance. At some point inside of a black hole, your feet would be attracted enormously more powerfully than your head, stretching your body to an extreme in a process some physicists jokingly call spaghetification. But let’s ignore problem for a moment and consider the nature of time in a black hole. We have already noted time slows as you near a point source of gravity. Black holes would be the most powerful gravitational point sources we can imagine. Consequently, the closer you get to the center of a black hole, the slower time would move. If you get close enough to singularity, time would stop, altogether. In effect, you could never reach the singularity of black hole. Of course, a few thousand other things would cause your demise a long time before you got close to the singularity, but rather than consider myriad of misfortunes, let’s leave our black hole and return home, to the present where in space and the present when in time. But we are going to embark on another adventure now. We are assigning ourselves god-like powers for a few moments, giving ourselves the privilege of reversing the flow of time in the universe. We are going to turn expansion into contraction and permit effect to precede cause in time. We are going to go back to the beginning, to the moment of “creation” itself. We watch as our sun and solar system disintegrate into a cloud of atoms and molecules. The hydrogen and helium that comprise our sun and the heavier elements that constitute the planets collapse back into an earlier star. The galaxies draw back together. Heavy elements return to the huge stars which created them. Eventually all the stars wink out and the universe disperses into hydrogen and helium atoms only, then those dissolve into smaller elementary particles and eventually quarks. As the universe shrinks, it grows enormously hotter. Eventually, the collapse completes as all the energy and mass in our present universe becomes a singularity, about the size of a single proton. Our entire universe is now a tiny black hole. We have returned to the moment of the big bang. As a black hole, our laws of physics no longer exist. In the singularity which is now the universe, there is no time. Time can not exist this close to a singularity. There is no moment “before the big bang” because, time now does not exist. So did a creator cause the big bang? The question becomes meaningless, as does a creator. There is no time for a creator to create. There is no space for a creator to create in, or exist in. With all due respect to those of faith, everything necessary for our universe now exists in a singularity and there is no “before” to question. As Stephen Hawking once so eloquently remarked, there is nothing south of the South Pole. We have reached the point where our western philosophical concepts of beginnings and endings become entirely without meaning. So, how did this singularity come into existence? We know that in the realms of the quantum universe, something is created from nothing all the time. Again, this is not a theoretical concept We have watched it happen. But it is a much more difficult subject, perhaps one to explore another time. For now, I simply leave you with the suggestion we have gone as far as questions are relevant. Copyright twenty eighteen. All Rights Reserved Dedicated to the loving memory of the late Professor Stephen Hawking. |
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