The Big Bang Theory- excellent essay, got a very very good mark

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Abstract This paper presents a new theory of the universe which updates the Big Bang Theory, and explains more of the phenomena that have been observed over the past 120 years.

INTRODUCTION

Since the 1880's, scientists have observed that light coming from distant stars has a red shift, indicating that those stars are moving away from us at high speeds. In the 1920's George Gamow proposed the Big Bang Theory, that the universe was created by a huge explosion, and that all the matter in the universe is still flying away from that explosion at enormous speeds.

The Big Bang Theory explains why stars in every direction show this red shift. The theory assumed that the Earth is located close to the gravitational centre of the universe, which is the presumed site of the Big Bang. So objects speeding away from explosion will also be speeding away from Earth at roughly the same speed.

There are, however, several things that the Big Bang Theory does not explain, such as the distribution of matter in the universe, pulsars, the apparent lack of anti-matter, the lack of sufficient mass to hold galaxies together, the seeming acceleration in the rate the universe is expanding, and the discovery of objects that are apparently older than the Big Bang. The purpose of the paper is to present a more comprehensive theory of the universe which explains all of these observations.

HOW BIG, HOW OLD?

The newest telescopes have allowed us to glimpse galactic clusters more than 13 billion light years from earth. The apparent distance of such objects is one of the primary indicators of the age of the universe. The universe must be at least as old as the amount of time it took light from these objects to reach us.

Objects that are very far away are receding from us at extremely high speeds. This causes the light from the objects to shift in wavelength. Light of a given wavelength will appear stretched out, that is, the wavelength will be longer. This lengthening is called the Doppler effect, or the red shift, since red has the longest wavelength of any visible light. We know that certain chemical elements, such as hydrogen, emit light with known frequencies. We also know the general composition of stars, primarily hydrogen and helium. Thus we can compare these known frequencies against the observed light. The faster the object is moving away, the greater this lengthening becomes. This tells us the speed of the object, and the speed tells us the distance.

Each time an extremely distant object is sighted, we need to revise the age of the universe upwards. For example, suppose we observe a galactic cluster 13 billion light years away, and receding at a speed of 0.75 times the speed of light. If that object had been created by the Big Bang, then we know that the object took a bit over 17 billion years to reach that position, so the universe must be at least 17 billion years old.

However, since the light from that object took 13 billion years to reach us, we know that 13 billion years ago the object was 13 billion light-years away, hence 17 billion years old, so it is now 30 billion years old.

There is a widespread theory that tries to explain away these very old objects by saying that, since the object is moving away at ¾ the speed of light, the light coming towards us is only travelling at ¼ the speed of light, and so the object is only ¼ as far away as it appears. This theory is nonsense. Light always travels at the same speed, regardless of the speed of the source or the speed of the observer. The absurdity becomes even more apparent if you consider a series of objects further and further away, receding at greater and greater speeds. Under this theory, the furthest objects would be deemed the closest.

There seems to be no limit to the process of discovery. Every time a new stronger telescope is deployed we find more distant objects than ever before, and the size and age of the universe need to be revised upwards.

WAS THERE A BIG BANG?

Recently, radiation that is consistent with a Big Bang about 13 billion years ago was detected. This is strong direct evidence for the Big Bang. Nonetheless, there appear to be objects in the universe that must be older than the Big Bang. We need to find a framework that accommodates both evidence.

There are two theories that can account for both the Big Bang and older objects. The first is the Oscillating Universe theory, namely that the universe periodically expands, then contracts, and explodes again. This would mean that objects older than the Big Bang could have arisen from earlier bangs. The second is the Many Bang theory, namely that the Big Bang is just one of many bangs at many sites, and the objects could have originated at any of many different sites and times.

Under the oscillating theory, all of the bangs would have occurred at the gravitational centre of the universe, at roughly even intervals of several billion years. The Many Bang theory allows for bangs at widely spaced locations with irregular timing, but does not preclude multiple explosions at the same site.

Let us imagine for a moment what took place at the time of the Big Bang. Matter was flung outward in every direction, with varying degrees of force, depending on where in the explosion's nucleus it originated. This means that matter would be spewed out at a wide range of speeds. Objects near Earth have very little shift in their light, and therefore are moving slowly (or, rather, are moving away from the centre at close to our own speed). Objects extremely distant from Earth have been observed speeding away at more than three-quarters the speed of light.

Now, suppose that there is sufficient mass in the universe to pull all of that matter back to the centre, in order to form the nucleus of another big bang. Matter would reach the centre at different times, depending on how far away it was, and how fast it had been speeding away.

STEADY-STATE THEORY

If it were necessary for all of the matter in the universe to be gathered in one spot in order to cause the next bang, then we would have a pure oscillating universe, called a steady-state universe, with the bangs almost evenly spaced, and of about the same intensity each time.

A steady-state universe can be pretty much dismissed out of hand for two reasons. The first reason is that no matter how much matter there is in such a universe, and how strong a gravitational pull it may exert, there is some velocity, called the escape velocity, beyond which an object could never be pulled back. Some of the matter in any explosion comparable to the big bang is certain to be ejected faster than this escape velocity, no matter how high that velocity may be. That means that each bang would be smaller than the last one.

The second reason that each big bang could not involve all the matter in the universe is that each explosion would have to be triggered by a mass exactly equal to the total mass of the universe. That is, since the explosion would have to wait until all the matter in the universe had collected back at the centre, the amount of mass needed to set off the explosion would have to be this precise value. There is no evidence that this is true, nor any reason to suspect it. We do not even know if there is a specific triggering mass.

It is also unclear that all of the matter would settle back to a single point. Over the past few decades a number of objects called "black holes" have been detected. These are objects so extremely dense and massive that their gravity prevents anything, even light or other electromagnetic radiation from escaping. Although black holes do not emit light, an object being captured by a black hole may be ripped apart by its gravity, and therefore give off bursts of radiation. Many such bursts have been detected, so we know that black holes must be very numerous. It is even theorized that there is a black hole near the centre of every galaxy.

Black holes are formed by gravity pulling together a great deal of matter at a single point. Once a dense centre forms, the capture of matter accelerates as the gravity increases. A galaxy is an ideal source for this matter. This means there are many points of concentration, many located very far from the gravitational centre of the universe.

MANY BANGS

Stars periodically explode. The explosions are called supernovas, and many have been observed. The brightest are visible to the naked eye, and a few have even been visible in daylight. The remains of these explosions are called nebulas, and some can be seen with relatively low-powered home telescopes. The most famous is the Horsehead Nebula.

A much bigger explosion, dubbed a hyper nova, was detected all around the globe in Dec. 1997. This 2-second burst of gamma radiation was described as being as bright as the entire rest of the universe. Simple logic tells me that such explosions probably occur between once every 10 years, and once every 1000 years. (If they were more frequent than every 10 years we would have seen more than one; if less often than every 1000 years there is little chance that we would have seen any in the mere 40 years that we have been capable of detecting them.)

The key point here is that explosions of differing sizes occur, so that the amount of matter needed to trigger one cannot be fixed, and must be far less than the total matter in the universe, or even the total matter in a single galaxy.

OK, so there have been many explosions of various sizes at numerous places. Can we extrapolate that to say that there have been many Big Bangs? If the most distant objects that we can see originated from some big bang, and if they are older than our Big Bang, then we can certainly conclude that there have been at least 2 big bangs. Since we have no estimated date for the previous big bang, and since we can't see anything whose origin seems to be much more than twice the 13 billion years since our Big Bang, we don't have adequate evidence for more than two. (Note that the preceding big bang would probably have occurred considerably more than 13 billion years before the most recent one. Since most of the matter from the last bang is still heading outward it is probably not yet the halfway point when gravity starts pulling everything back.)

BUBBLE DISTRIBUTION

There is additional strong evidence for the Many Bang theory. This evidence is the distribution of matter in the universe. Much of the matter we can see appears to be concentrated in spherical shells, or bubbles. This distribution is precisely what would be expected from many bangs.

Each time any bang occurs, matter is spewn out in every direction. Over time, gravity pulls it back towards the point of the explosion. Matter ejected relatively slowly, which therefore remained close to the explosion site would have been pulled back long ago. Matter ejected rapidly, and thus further away, will have been slowed less. Some of it will still be moving away, while some will have begun to fall back towards the gravitational centre.

There is a roughly spherical front where material ejected from the explosion will have slowed to zero velocity. Matter beyond the front will still be moving outward, the further from the front, the faster it will be moving. Matter within the front will be falling back towards the centre, the closer to the centre, the faster it will be moving. Matter close to the front will be moving slowly, either inward or outward. Thus, in the region of the front, matter will be densest. Matter much further out will be moving much faster, and therefore will be sparse.

PULSARS

Another phenomenon that gives credence to the Many Bang theory is pulsars. These are objects that give off pulses of light at regular intervals. The conventional explanation of pulsars is that they are massive neutron stars spinning rapidly and giving off a pulse of energy on each rotation, typically a few milliseconds up to a few days. This theory is very unlikely for two reasons.

First, these objects are so massive that it would take tremendous energy to get one spinning rapidly. A neutron star is matter condensed from a nebula that is left after a star has gone supernova. Initially it would be spinning at the same rate as the nebula, say once every 100,000 years. To speed such a massive object up to even one rotation a day would take titanic energy. Collisions from objects it captures by its gravity would be likely to slow it down (due to conservation of angular momentum).

Second, just because it is spinning is not a reason for it to give off bursts of energy. A neutron star is likely to be fairly homogeneous, and its electromagnetic field should be cylindrically symmetric (that is, symmetric around the axis of rotation). There is no reason to assume that it has some "energy geyser" on its surface that spews out a plume of radiation. Quite the opposite: once a neutron star captures matter or energy there is little chance that it could escape.

The Many Bang theory offers a much better explanation for pulsars. At any time there are many, perhaps billions, of centres or nuclei being formed for future bangs. It is likely there is one at the centre of every galaxy, or galactic cluster. These are continually capturing objects through their gravity. When a large object is being sucked in, it may plunge straight in, or it may spiral in, depending on its motion before capture. When such an object spirals in, the gravity of the black hole will rip it apart.

This process may result in a continuous release of radiation. Much of this radiation will also be captured by the black hole, but some radiation released in a radial direction away from the black hole will escape. When that direction is pointing towards the earth, we can detect it. So, each time the object reaches the point in its orbit where the escaping radiation points towards earth, we see a burst or flash.

This would also explain why some pulsars flash with two distinct periods. They are capturing two objects simultaneously, one closer with a fast period, and one further out with a slower period. By chance, it happens that points in both orbits are aimed towards earth. Eventually, I predict, we will detect pulsars with 3 or more distinct periods of flashing.

This means that pulsars are probably much more numerous than we now imagine, but we cannot detect most of them because either they are not currently capturing a large enough object, or the orbits of objects being captured never point towards earth. Consequently, black holes are also far more numerous than the ones we have observed.

WHAT'S NEXT?

There are several consequences of the Many Bang theory that need to be considered. The first is the relationship between red shift and the age and distance of various objects. The current equation relating red shift and distance is based on the premise that all such objects arose from a single Big Bang at the gravitational centre of the observable universe. Since Earth is fairly close to the centre, distance from Earth and distance from the centre are close enough to consider the same for this purpose.

If an object arose from a different bang, at a location far from the centre, however, this approximation would not hold. An object with a small red shift could actually be very far away because it originated from an explosion far away.

In most cases, this is not a problem. If we are talking about a local explosion of matter that originated from one of the big bangs, then the bits of material produced would be too small to see individually, while the whole mass that produced the explosion would still be moving away at the same velocity it had prior to exploding. This is a simple consequence of conservation of momentum. Most of the very distant objects we can detect must be primary products of a big bang, not the smaller secondary products. On the other hand, if we mean an object produced by another very distant big bang, it is probably still too far away to see yet.

OTHER UNIVERSES

If there have been many bangs at many locations, it is possible that some of them are comparable in size, or even much larger, than our own local Big Bang. This means that there may be other clusters of matter even bigger than what we currently call the universe. Although we could not expect to see individual galaxies, or even galactic clusters, within such a distant object, we might be able to see the entire object. An object of that size could rightfully be called another universe.

It is possible that we have already seen such universes, but have not recognized them because they do not exhibit a large red shift. Indeed, the portion of such a universe nearest us may be approaching at a high speed due to its own big bang. The object would then have the opposite of a red shift, called a purple or violet shift. We would interpret such an object as being small and nearby, rather than huge and vastly distant.

This opens the door to the likelihood that space is filled with matter, rather than the prevailing assumption that all matter is fairly local because it was created by a single Big Bang, and therefore could not have travelled more than 13 billion light-years. Such a cosmos could be permanent rather than having a limited age. In other words, there is no beginning of the universe, and likewise no beginning of time.

ANTI-MATTER

One of the most fundamental laws of physics is that matter can be neither created nor destroyed. If you assume all of the matter in the universe came from a single Big Bang, then this presents a problem. How did the Big Bang create all of the matter that we observe? The traditional theory is that no matter was created, rather the Big Bang created exactly equal amounts of matter and anti-matter, so that the total amount of matter in the universe was 0 before the Big Bang, and is still 0. Nothing was created or destroyed.

The difficulty with this theory is that we observe large amounts of matter, but very little anti-matter. The traditionalists maintain that the required amount of anti-matter is out there, we just don't know how to detect it.

On the other hand, if we assume matter has always existed throughout the cosmos, then there is no such problem. There is no need to ask how matter came into existence; it was always here. There is no need to require a precise balance between matter and anti-matter. We can accept a universe with lots of matter and little anti-matter, if that should prove to be true, or the converse if our little corner should be atypical.

ENERGY

An extension of the theory that the total matter in the universe is zero, is that the total energy in the universe is zero. Since neither matter nor energy can be created or destroyed, the Big Bang theory needs to explain where all the energy of vast quantities of matter hurtling outwards originated. The conventional answer is that this kinetic energy is exactly balanced by the potential energy of this same matter, should it all be pulled back by gravity to the centre. Thus the total energy in the universe would be zero.

This is an inadequate explanation. Obviously all of this kinetic energy originated from the Big Bang. So, where did the energy for the Big Bang originate? It cannot be from the conversion of matter into energy, since there was no matter before the Big Bang.

This problem does not occur in the Many Bang theory. In this view of the universe there has always been both matter and energy, and the conversion of one into the other can take place freely.

MISSING MASS

One of the puzzles that has engaged astrophysicists lately is the problem of the missing mass. This problem occurs if you assume an oscillating universe. There must be enough mass to pull all the matter in the universe back to the centre for the next bang. The amount of matter that we can currently detect is only about one-tenth enough to do this.

Once again, the problem does not occur for the Many Bang theory. Bangs can occur anywhere that there is enough mass to pull together the nucleus for an explosion of any size. It is widely believed that every galaxy has a black hole at its centre, and this has the potential to pull in the required material for another blast, of super-nova size or larger.

It is worthwhile noting that when any of these bangs occur, some of the matter being ejected outward will collide with matter still being pulled inward by gravity. This will create secondary explosions, and the release of additional radiation. It will also stop some of the matter from hurtling outwards, and lead to the speedier formation of a new central nucleus at the same location.

CONCLUSIONS

The universe is a far larger and more complex system than the Big Bang Theory predicts. Matter is distributed throughout the cosmos, and travelling in every direction. Red shift alone cannot determine the age and distance of every visible object.