Theory of relativity as basis for Black hole.

Einstein's Theory of relativity is definitely one of those few theories in the history of physics, that changed the way we see things. It revolutionized the cosmology in such a way that many physicists who are struggling in their respective lines of research produced some shockingly interesting results.

Black holes is one such shocking yet interesting result....

So, what is a black hole?

Well, there are a lot of definitions, and in the simple possible way: A Black hole is a region in space-time with such an immense gravitational pull towards its center that even light cannot escape out of it.

How is Einstein's 'Theory of relativity' responsible for its formation?

Black hole is a subject where its formation is almost entirely based on theoretical evidences rather than physical evidences(strong). All these theoretical proofs are in fact been implied from the Theory of relativity.
To get some idea about its formation and stuff, we must know the life cycle of a star as a prerequisite.

A star takes birth when large amount of nearby gaseous particles(mostly hydrogen) attract towards each other and get squeezed.
In this process of contraction, particles collide with each other to produce large quantities of heat energy. This heat in fact is responsible for the star to shine brightly. The heat thus produced would be so immense that, the particles when they come closer will no longer collide but coalesce, and forms higher elements like helium, Lithium, Berilium...along with some amount of heat. Heat that got released in this process, creates high pressure between the particles and tries to drive them away, opposing the contraction process. The more the star tends to contract, the more will be the opposing pressure.
At some stage there will be a perfect balance between the contraction(force) and expansion(force) helping the star to remain stable. The star thus remains stable for quiet a long period of time(million millions of years) till one of its forces gets weaker. Obviously, it can't be the gravitational force(contraction) that gets weaker.
The pressure inside the star eventually gets weaker, and the denser particles that gets cooled drift towards the center of the star, re surging the contraction process. This process continues till it reaches a stage where, the contraction force gets even by the repulsions between subatomic particles(electrons, protons, and neutrons). The star thus remains stable again for the second time.

The star that gets balanced by the repulsions between 'electrons' is termed as a
'White dwarf' with a radius of about few thousand miles and with a density of about hundreds of tons per cubic inch. And the one that is supported by the repulsions between protons and neutrons was popularly named as 'Neutron star' with a radius of about ten miles(only) and density, hundreds of millions of tons per cubic inch.

This would be the final stage of every known and unknown star that exist in our known and unknown universe, if the subatomic particles could move with out any limit. But, according to Einstein's Theory of relativity, nothing can travel faster than light.

Here comes the interesting question: What if the star is so heavy that it requires the electron(or proton or neutron) to move faster than light--to balance the immense contraction(force)?

These kinds of movements or repulsions among the subatomic particles are impossible according to the Theory of relativity and hence the star ends up in a gravitational collapse, and forms an infinitely dense region, popularly called as a 'Singularity'.
The star that gets vanished in to a 'singularity' still exerts the same, finite light trapping gravitational pull(can be more but not less) up to certain distance in space creating a 'Black hole' around it. The boundary of this 'Black hole', the 'Event horizon' is formed by the paths of light just managed to move around but can't escape.

Thus the whole Black hole formation was almost based on Einstein's 'Theory of relativity'.

What if the electrons under those special conditions(gravitational collapse) could move with out a speed limit--faster than light ?

There will be no 'Singularity', no 'Black hole' but will be a 'Black star' or 'Dark star' that still can trap light.
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The uncertainity principle by heisenberg

To get some clear understanding about the uncertainty principle, first, we need to know the quantum hypothesis.

Max Planck suggested that light, X-rays, and some other waves could not be emitted at the arbitrary rate, but in the form of energy packets called quanta.

According to the quantum hypothesis, each quantum--packet-- has certain amount of energy that was greater the higher the frequency of the waves. That implies that at higher frequencies, the emission of even a single quantum would require more energy than that was available. Thus the radiation at high frequencies gets reduced.

In order to predict the future position and velocity of a particle, one has to be able to determine its present position and velocity accurately. The only way to do this is to shine light on the particle and this will indicate its position. To determine more precisely one needs to use light of short wavelength(high frequency). Now, by Planck's quantum hypothesis, one cannot use an arbitrarily small amount of light; one has to use at least one quantum and this quantum will disturb the particle and change its velocity in a way that cannot be predicted. The more accurate one tries to measure the position, the greater will be the disturbance ( as it needs high energy quanta ). In other words, the more accurate one try to measure the position of a particle, the less accurate will be the speed and vice verse
This principle put an end to a notion(came from Newton's theory of gravity) that our universe is completely deterministic ( one can easily predict everything that would happen in the universe, if he knows its present state.)
It is only possible for the one who could observe the present state of universe with out disturbing it.

check this video.

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Ptolemy's geocentric Theory

Ptolemy proposed his Geocentric theory in the 2nd century A.D. What he did was just an elaboration of already existing idea that earth was in the center of universe, proposed by Aristotle, in to a complete cosmological model.

According to his theory, the earth stood at the center, surrounded by some eight spheres, the Moon, the Sun, the stars, and the five other planets known till the time: Mercury, Venus, Mars, Jupiter, and Saturn.

The first sphere supposedly carried Moon followed by Mercury, Venus, Sun, Mars, Jupiter, Saturn, and some fixed stars--eighth sphere--in the remaining seven spheres. The outer most sphere that is supposed to carry the so-called fixed stars, rotate across the sky; the stars thus remain fixed with respect to earth--according to him.

What about the region beyond the eighth sphere ?

He didn't explained that, as there is no way one can observe beyond stars--no telescope and no Galileo.

Does this theory provided a reasonably accurate system for predicting the positions of heavenly bodies in the sky ?

Yes, it was, but got one serious flaw: to predict the positions correctly, Ptolemy had to make an assumption that the moon followed a path that sometimes brought it twice as close to the earth as at other times. And that meant that the moon ought sometimes to appear twice as big as at other times!
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What makes a star shine ?

A star is formed when a large amount of gas (mostly hydrogen) starts to collapse in on itself due to its high gravitational attraction. As it contracts the atoms of the gas collide with each other more and more frequently and at greater and greater speeds--the gas heats up. Eventually, the gas will be so hot that when the hydrogen atoms collide they no longer bounce off each other, but instead coalesce to form helium. The heat thus released in this reaction, which is like a controlled hydrogen bomb explosion is what makes the star shine.
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Space and Time-not absolute

To know why time is not absolute, we must date back in time and have to see the evolution of theories regarding space and time. At first, Aristotle proposed that the natural state of a body is to be at rest and starts moving only when it gets acted upon by some external force. It followed that a heavy body should fall faster than a lighter one on to the Earth. Later it was proved wrong by Galileo,and Newton proposed his three laws on the basis of Galileo's experiments. He proposed that, the natural state of a body is not to be at rest but to be in uniform motion and only when it gets acted upon by some external force, It starts accelerating. It follows from Newton's laws that there is no unique standard of rest. Lets for instance, a train was moving past an electric pole standing tall along the embankment, at a speed of 70 mph, one could equally say that the pole was at rest and the train was in motion or the train was at rest and the pole was moving past at the rate 70 mph; we can't really say which one is at rest preferably. If for someone inside a train which is in motion, an object appears at rest, and it appears in motion for someone outside the train. This implies, we can't assign any event an absolute position in space. hence space is not absolute.
They came up with non absolute space but still it was believed that 'time' was completely independent from 'space' and that one can unambiguously measure the interval between any two events that happen in space. In 1676, Christensen Roemer came up with a significant discovery that light travels at a finite speed and he calculates it to be around 140,000 miles per second, However later Clerk Maxwell precisely measured it to be 186,000 miles per second. Whatever it is, It adds a significant implication that light travels at a finite and more importantly fixed speed.
Here comes the most interesting part, if light has to travel at some fixed speed, It must travel relative to something at rest and what could be that 'something'?
They came up with a shockingly interesting and imaginary space, 'Ether', supposedly presents everywhere and obviously, at rest.
Later scientists tried to measure the time taken for the light (from a fixed source) to reach an object that is moving towards it, in one instance and moving away from it in another instance. Shockingly, they measured the same 'time' in both instances.
At that stage Albert Einstein came up with his famous Theory of relativity, which implies that time is not absolute, obviously no need of ether anymore. A remarkable consequence of relativity is the way it has revolutionized our ideas of space and time. In Newton's theory, if a pulse of light is sent from one place to another, different observers would agree on the time that the journey took (since time is absolute), but will not always agree on how far the light traveled (since space is not absolute), Which implies that different observers would measure different speeds of light. In relativity, on the other hand, all observers must agree on how fast light travels. They still, however, do not agree on the distance the light has traveled (since no absolute space), so they must now also disagree over the time it has taken. In other words, the theory of relativity put an end to the idea of absolute time, which means that time measures between any two events in space by two identical clocks would not necessarily agree, even though they show the same.
We must accept that time is not completely independent from space, but is combined with it to form an object called space-time

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Time travel- third possibility

Phi masons which are highly unstable particles decay pretty quickly, but when they are accelerated at the speed closer to light they lasts 30times longer, which means that time travel is possible if we can accelerate closer to light's speed

lets for instance, our physicists successfully built a track along the earth's circumference and designed a train that can accelerate closer to light's speed. If the train has to travel at the speed of light, it has to circle the earth 7 times in a second, that's something we can't even imagine..right, anyways we can't cross or even reach the light speed but can get closer enough to travel in time, closer in the sense 99.9% that of light's speed. As the train begins its journey and starts accelerating at the rate 99.9% that of light's speed, the time inside train starts flowing slowly when compared with the rest of the world. Their 1 week of travel inside train equals 100 years for us and they will unboard to see the future earth.

What if a child inside the train starts running, does the added speed cross the speed of the light ?

The answer is no, because as he gets closer to the speed of light he feels heavier and heavier and to reach that point he need infinite energy which is practically impossible.

The Apollo with a speed of about 25000 miles/hour is so far the fastest space vehicle. To travel in time, we need much faster and much heavier one, almost 2000 times faster.
The design says, the initial acceleration of that massive ship is very small but picks up acceleration to reach half the speed of light in 2 years and 2 more years it reaches 90% that of light speed at that time, its would reach our nearest solar system ,Centurion. 2 more years, 99.9% and starts traveling in time. one day on board equals to a whole year on earth.To reach the edge of the galaxy all they need is just 80 years

Most of the time, we try through the right methods to solve wrong problems. Identifying the right problem is the challenging task and once we are through with this, then solving it becomes simple and easy.

click here to know first two possibilities
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time travel possibilities in detail

Time is considered as fourth dimension with the other three dimensions being filled with space. Until now we all know how to travel in space. In the near future, it is more than a possibility that we can even travel in time. Time travel is no more a fantasy.
three of the possibilities have been under consideration so far and im going to explain the first one here
first possibility:
Nothing in the world is so plain, lets take a snooker ball, if we can observe it more closely, we can notice wrinkles and holes on its surface. If we can go deeper and deeper down the smallest scale smaller than molecules,smaller than atoms we will land in to a place called quantum world. This is the place where worm holes appear at a size of around billion trillion trillionth of a cm. These infinitesimally small holes actually are gateways for our time travel.
Scientists believe that these worm holes can be made to appear in large scale and if someone dares to dive into it, he might even travel back in time and reach a point in past.
But lot of physicists been asking a question like if it happens that someone, lets say 'x' went in to past and kills his own self, who is 'x' then. It violates the fundamental law of universe. This is a major drawback and has its own serious consequences.
But this is not the end, the other two possibilities are far more interesting
second possibility
This one stems from Einstein's theory of general relativity. GPS, which is formed by hundreds of satellites revolving around the earth explains this concept better.the atomic clock that is equipped inside them is so accurate that it just delays in the order of 10⁻⁹ seconds per day. Even being so accurate, it needs massive corrections at regular intervals along the orbit.the problem being time warp, which means that time being very linear acts non linearly at certain points in space.they even exist on earth.
Giza pyramid, which weighs around 40 million tons is surrounded by time warp. somebody who stay closer to that experience relatively slower drift in time. For an observer who stays closer to Giza pyramid, outside world appears a bit hurried.
If we really want to traveling time, we need something much more massive than Giza pyramid. Fortunately the center of our galaxy is equipped with a super massive Black hole on the order of hundreds of billions of solar masses. It can slow time more than anything in our galaxy. Time gets warped near the super massive blackhole because of its heavy gravitational pull. Lets say if our scientists had built a space ship tthat can reach the center of Milkyway and is set to orbit around the super massive blackhole, for every 60 min of orbit,crew inside the spaceship experience 8 min lag. Round and round they go the ship and crew travels in to future more swiftly. Their 5 days of orbit around the super massive blackhole almost equals 8 years on earth, and when they return they would see the future.
Building a spaceship to orbit around such a massive blackhole, withstanding its massive gravitational pull is almost impossible, but there is one last and best hope of time travel...


click here for third possibility

check this video


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