Every one of us wonders what will be the end of the universe? How it’ll end? As the big bang was the beginning of the universe, what’ll be the fate of the universe? Earlier, we gave concentration on the beginning of the universe much more, now we are giving some more attentions on the fate of the universe (though scientific researches & concentrations are still going on). This question is more common among astrophysicists & cosmologists.
For the kind information of readers, I’d like to introduce the definition of cosmologist & cosmology. Cosmologists are actually astrophysicists who study cosmology as their special research field. And cosmology is the sub-part of astrophysics which is the study of the whole universe as a whole in large-scales, its origin, end, future developments & nature. For more information, Prof. Stephen Hawking of Cambridge University, the greatest physicist of the era after Albert Einstein, is also a cosmologist. His field concentrates on cosmology.
It’s a matter of discussions among top cosmologists around the globe that what’d be the probable end of the universe. We’ve well got a good idea on the beginning of the universe. But there are still a lot to know about the universe.
So, let’s begin a journey through the deepest of the fate of the universe unveiling the greatest mysteries of the universe where truth is much stranger than the reality. In the beginning of the century, scientists have developed a good insight on the end of the universe. Although, there are a lot of controversies, cosmologists have sorted out some of the best theories.
At the very beginning, we’ll discuss the big crunch theory. Big crunch theory is a theory which states that the universe will end in a collision course. As estimated by Wilkinson Microwave Anisotropy Probe (WMAP) in 2001 that the 26% of the universe is filled with matter particles (22% non-baryonic & 4% baryonic), we expect that the universe will end by a collision by gravity. The idea is that after expanding the universe to a critical state, the universe will start to collapse due to the gravity of the mass. This idea is supporting to an extend. Now, the universe is expanding in an accelerating state. The reason behind this strange, yet interesting phenomenon will be discussed later below. The universe is expanding unbelievably now. After a lot of years later in very distant future, the universe will not be eligible to fight anymore with gravity. After this rapid expansion, the universe will reverse its state. Rather expanding rapidly, it’ll slowly begin to slow down. Everything will begin to reverse. The idea is such that if you put coffee in a cup & give it to your guests, the coffee will begin to fly away from the mouth of the guests. Then, the coffee cup will go away from the hand of the guests to the tray in which you’ve give them. Like this, every movement will be reversed. By the use of my Quantum Time Theory, we could notice that actually this is not the simple reversing of the movement of everything but the whole time. Because according to quantum time theory, time is particles’ motion & the reversing of their motion is the reversing of time. By using this conception, we can have a model of future time machines. The arrow of time (direction of time or direction of overall motions of all the particles) will get reversed to the opposite direction. Anyways, everything will be reversed. Now, may be everything will not reversed to its earlier states. But it is sure to say that everything will be collapsed under their gravity. Though, it’s not scary here in the written form. But the truth is scarier. Actually, the idea will be so that after the critical density or maximum expansion of the universe, everything will begin to collapse. After collapsing to a millimeter, the collision will begin at atomic levels. Now the atoms will begin to collapse with each others & yes to that extend, the life on earth or any other places in the universe will die very scarily, unbelievably & harshly. The rubbing within the atoms will also cause heat energy. So, atoms will start to go apart from each other but the strong force of gravity will no more allow them to do so. So, the collision state will go on further & now every single elementary particle & of course the dark matters (those particles which are not yet known to science & of course to periodic table) will collapse to a single point, the so-called singularity where there will not be anymore spaces or will have very little spaces between particles. This is a nightmare of physicists of course because every single laws of nature break down there. Then, the universe will settle down to collapse anymore. The violent universe will turn normal & peace. There’s an idea that this singularity will lead to another universe but the idea differed nowadays. We’ll discuss this later. Now, the big crunch maybe correct or maybe not. This is the first theory. We’ll discuss the second theory of the fate of the universe just later. Here is a picture dealing with fate of the universe describing the big crunch theory:
Fig: 1.1 THE BIG CRUNCH THEORY
There are a lot of prospects in the big crunch theory. Maybe the universe ends with a crunch. No one knows exactly what is the reality, what will the fate of the universe. But the present researches & studies are turning back from big crunch theory. The reality is heading towards another theory & this will be our next discussion. Let’s see.
The second possible theory of the fate of the universe is the big freeze theory. According to this newborn theory, the universe must end up in an infinite cosmic expansion. Everything will be scattered infinitely even does the atoms or other particles. Now have a look in the theory & the new insight. As the data retrieved from the WMAP satellite, the universe contains 74% dark energy, 22% dark matter & 4% baryonic matter. For now, dark energy might be stranger for you. Dark energy is actually kind of unknown mysterious energy which acts like anti-gravity, i.e. unlike gravity which attracts matter, dark energy repels them. This is a new form of energy about which there are a lot to be known yet. In the distant future of our universe, the dark energy will totally pull the whole cosmos apart, even it’ll pull the strong nuclear force between the fermions (matter particles). I’ve here italic the word “totally” because this task of repulsion is going on & in the future, it’ll be totally achieved. In the 1998 (my birth year), astrophysicists headed their million dollars space telescopes toward supernovas (a catastrophic explosion in massive stars followed by their deaths). What they found is so surprising & strange that the whole scientific community get shocked. According to theory or logic, what goes up must come down. That means to say, if the universe is expanding, it must slow down & contract followed by a big crunch (the conception of the big crunch theory). If the universe still doesn’t contract & expand, it must slow its speed. In this hope astrophysicists look at the supernovas. Scientists normally use supernovas to do the task because in general they are convenient to do such tasks as they don’t change their position, they do only when the universe itself change. But the result of the observation was totally different from what astrophysicists hope for. The research shows that the universe was neither contracting nor even slowing its speed down, but the universe was accelerating in an ever-increasing rate! The universe’s speed doubles as the distance doubles (Hubble’s law). This acceleration is actually not only strange to scientists but also to general people. As in the normal day-to-day experience, we find that if you bounce a ball towards sky, after a couple of minutes it must slow down by gravity & ultimately fall down on earth. What would be like if the ball will fly to the sky in an ever-increasing speed? It’d be a strange fact for people because there must be other unknown forces which increase the ball’s speed. So does to the expansion of the universe. There is an unknown force which drives the universe in acceleration. In 2001, WMAP satellite revealed that there is an unknown force which helps in the acceleration of the universe & scientists named the force as dark energy. This is the force which helps in the ever-increasing speed of the universe. Though strange, it’s the established fact. Not only had the presence of the dark energy, WMAP revealed the entire composition of the universe in percentages. Here is the pie chart of the composition of the universe & we’ll figure out an important fact about the possibility of big freeze from this:
Fig: 1.2 Constitute of the universe
By observing the pie chart of the constitute of the universe, we could figure out an important fact. We found here that 24% is dark matter, 4% (3.6% + 0.4%) is baryonic matter & total matters are 26%. Now, both the types of matter will generate gravity & thus it support big crunch theory. On the other hand, we could figure out that the 74% of the universe is filled with dark energy which is an anti-gravitational force & support big freeze theory. The important fact here is that 74% of the universe is filled with dark energy & 26% is filled with matters. Now, which one fills the universe in greater proportion? Dark energy or matters? Anti-gravity or gravity? Expansion or contraction? The side is towards dark energy & its associates anti-gravity & expansion. A large part of the universe is filled with this dark energy. Dark matter & baryonic matter (matters) are in very small proportion. This is the fact. From this fact, another fact can be found & this is that big breeze theory is likely to happen in the future. The universe will end in an infinite expansion where every matter particles will be scattered leaving the whole universe lonely. There’ll not be any density in the universe as everything here is infinitely far from each others. The situation of the universe at that time will be like the one after infinite expansion in fig: 1.1. The fate of the universe is in the hand of big freeze. The presence of dark energy is really enough to expand the universe infinitely leaving gravity worthless. The excessive presence of dark energy is the supporter of big freeze theory. Now, we will introduce another such supporter of this theory. This is the cosmic inflationary theory. According to this theory, the universe begins as a bubble out of quantum fluctuation. Not only this, there is a term called multiverse linked to this inflationary theory. Multiverse is related to the numerous universes out of which our universe is one. As estimated, there are 10500 (10 followed by 499 zeros or 1000000000000000000000000000000000000000… until 499 zeros) universes. These all universes are like bubbles in boiling water. There’re some particles called tachyons which destabilize the vacuum. After that destabilization, there’re will be quantum fluctuations & the results of these fluctuations will be infant universes or bubbles. These universes will at first, will be in the size of particles. Later, they’ll develop & expand to what we see today. When 2 such universes collide they give rise to other universes as in the case of bubbles of water. These universes expand infinitely & end in bursts as the bubbles of water end in bursts. Now, we can think that universe will expand infinitely & then end in a burst scattering everything here & there. This is also the prime supporter of big freeze theory because this theory states that universe end in a bang of burst. And the big freeze theory also states that universe will end in an infinite expansion. This expansion will be followed by a burst. And thus, the universe will end. These are the basic ideas of the big freeze theory.
These 2 are the basic theories related to the fate of the universe. There are 2 agents related to the fate of the universe as well as to the big crunch theory & big freeze theory & these 2 agents are gravitational force & dark energy (anti-gravity). Universe is more filled with dark energy than matters so the luck is with big freeze theory & of course the cosmic inflationary theory is also the prime supporter. So, chance is more with big freeze. Maybe the universe ends in a big crunch. Who knows the truth? And yeah maybe the universe ends in a big freeze. There maybe yet another theory. Maybe universe end as a result of collision with another universe. This is also a chance. As some universes do, our universe may also collide with another nearby universe & end in a big collision. Yeah maybe the big collision theory (I just named it now) is right. Our universe will collide with another universe & end followed by giving rise to another newborn universe. There’re a lot of ideas. But who will win the cosmic tug-of-war is still a question to scientists & the whole humanity. Till then, just wait…
Copyright ©2011 Sandeep Deba Misra