Before The Big Bang
What is the fundamental thing that makes up matter? Do extra dimensions exist? If they do, where are they? Do parallel universes exist? How our visible universe was created?
Imagine you could find an explanation for everything in the universe, from the smallest events possible to the biggest. This is the dream which has captivated the most brilliant scientists since Einstein. But to make the dream true they needed “The theory of everything” which will unitie all the four fundamental forces into a single equation. The four forces (gravity, electromagnetism and the strong and weak nuclear forces) would be unified by an equation perhaps one inch long. During the last thirty years of his life Albert Eienstein sought, relentlessly for this theory and he came up empty handed and once said “Nature shows us only the tail of the lion”. But now scientists says that they have got that theory and that is the super string theory.
In the heart of string theory:
Five theories of everything!At first of early nineties there was total five distinct string theories in 10D space.The theories are So (32), Type I ,IIA,IIB & E8 X E8 heterotic.In that time string theory was said as “The theory of everything”. But it has five types. So it there are five theories of everything! and it is really impossible because we need only one. Besides Michel Duff (University of Michigan) and his team combined gravity and super symmetry which is called supergravity. Their equation said that totally there will be .11 dimensions where string theory said 10. So with everything string theory was in an embarrassing position. They were trying to add the eleventh dimension. It might rescue them.
Brane world:In 1995 Joe Polchinski of the University of California in Santa Barbara electrified the string-theory community with a major discovery that has subsequently impacted every field of physics. He discovered D-branes.D-branes are surfaces where the free ends of open strings are fixed. They come in various dimensions. 0.2-branes for example are two dimensional and can also be called D2-membranes, or super membranes. D0-branee are like particle like and D1-branes are string like. Higher dimensional objects can exist as well. D-branes are essential for making string-theory mathematically consistent, and have far-reaching implications for a theory of quantum gravity.
M-theory:
The 11th dimension:
Parallel Universes:
Lisa Randall (Harvard University) had been fascinated by an apparently inexplicable phenomenon: the weakness of gravity.We know there are four fundamental force in our universes. If we assume the intensity of gravity ‘1′, then the intensity of weak Nuclear Force-10*30, strong Nuclear force- 10*40 and strong Nuclear force-10*42 (42 zero after 1). So gravity is extremely weaker than the other three forces. Now you might look around and say gravity does not seem weak, but if you think about if you have the entire earth pulling on you and yet can manage to pick things up.When M Theory emerged, Randall and Sundrum (John Hopkins University) wondered if it might be provide and explanation. Could gravity be leaking from our universe into empty space of the eleventh dimension?Randall tried to calculate how gravity could leak from our membrane universe into empty space, but she couldn’t make it work. Then she hard a theory that there might be another membrane in eleventh dimension. Now he had really strange thought. What if gravity was not leaking from our universe but to it? What if it came from that other universe? On that membrane or brain, gravity, would be as the other forces, but by the time it reached us it would only be a faint signal. Now when she reworked her calculations everything fitted exactly. So our gravity is just a weak signal leaking out of another universe into ours which spends most of the time near the other brane. We only feel the tail end of gravity.The weakness of gravity could at last be explained, but only by introducing the idea of parallel universe. Randall’s idea opened a pandora’s Box. Now suddenly physicists all over the world piled into the eleventh dimension trying to solve age-old problem and every time it seemed the perfect explanation was another parallel universe. Everywhere they looked it seemed they began to find more and more of them.within no time at all eleventh dimension seemed to be jam packed full of membranes. These membranes were possible other parallel universes. In those universes there may be people like us or not, may be different kinds of laws of physics.So M-theory was getting more and more stranger. But could it really be a theory which explained everything in our universe? Did it answered what caused the Bigbang, it mean the explosion from which our universe was created?
Before the Big bang:
Imagine there is an enormous ship standing at harbour which is 150 or 200ft high. This giant wave suddenly jumped from sea surface to air & crushed its windows. It means from 2d to 3d. Burt ovrut suggested our universe is moving through the eleventh dimension like giant, turbulent waves.Burt’s idea caught attention of the physicists and cosmologists. After a conference in Cambridge in which he explained this idea first time, Neil Turok (Cambridge University), Paul Steinhurdt and Burt decided to discuss about bigbang. Started to throw ideas. Suddenly they knocked at the right door and the mystery of bigbang opened.The idea was——-If two brains collide each other then it produces all the effects of early universe. It means Bigbang is the result of the collision of two brains or parallel universes. But the problem was things are not smooth out in our universe. In fact we have little clamps, we have galaxies & lumps of matter. Now they had to explain how the collision of two parallel universe could go on create these lumps of matter. Could they solve it?Yes, they solved it. They answer was — people tended to think of brains as being flat perfect sheets, geometrical plains, but the picture could not be correct. It cannot be perfectly flat. It has to ripple. When the rippling brains approach to each other and collide they don’t hit at exactly the same time, same place, but in fact they hit at different points and at different times. This rippling collision produces lumps of matter.So they finally had their complete explanation of the birth of our universe and the latest understanding of the universe is that there could be infinite number of universes each with a different laws of physics. Bigbangs probably take place all the time. Our universe co-exists with other universes which are also in process of expansion. Our universe could be just one bubble floating in an ocean of other bubbles. Perhaps out there in space there is another universe heading directly towards as — it may only be a matter of time before we collide.
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