Illusion of Time-- Time Dilation || Twin Paradox || Special Theory of Re...

Illusion of Time: Twin Paradox, Time Dilation, Gravity, Time Travel

What is time? Time is an illusion! An ultimate quest in philosophy and science, I would say. Time is the ongoing sequence of events taking place. Time is relative, and flexible and, according to Einstein, "the dividing line between past, present, and future is an illusion". So, reality is ultimately TIMELESS. We have created or rather defined time to live in the space.  Space may not be the fundamental ingredient of the cosmos but rather a fundamental side effect that emerges from particles interaction.  That space is measured in time. Time is a distance travelled in space! Space comes along with time; it’s never ever existed without time. Time is measured in a vector scale in a space. 3-dimensional of space is—up-down, side-to-side, and back and forth. The fourth dimension added to it is time.  Time is used to describe events in 3-dimensional space.

Time in physics is operationally defined as "What  a clock reads".  Great Einstein told that time is not absolute; it’s a relative term and depends on which frame of references we are talking to. Each individual has his own personal measures of time that depends on where he is and how he is moving. For example, the person travelling in a train thinks he is in rest and rest of the world is moving but for an observer, standing in a platform, he is in motion.  Like on Earth we are still but for an observer, outside the earth, we are moving because earth is moving round the Sun. Both the observers are fully entitled to say that they are stationary and the other one is moving. This is the Special theory of relativity which talk about the inertial frame of reference.  Inertial frame of reference simply means which runs with constant velocity and no acceleration applies on it.

According to Einstein, there is no difference in the box that is on the surface of the earth and subject to the gravity of g and the box is accelerating in an outer space with velocity g.  There is no way for an observer to tell whether he is moving or standing still. The acceleration is balanced by the gravity in an opposite direction. The person in an accelerated box falls on the surface of a box and feels the effect of a gravity.

Einstein  said both the two things are equivalent! A person who is travelling in a space time, right side graph is the  journey is space time.  And by the principle, the person who is stationary on the earth but subject to gravitational attraction g, must also be travelling in a space time. Though, he is not moving!

Time is relative and depending on observer’s perspectives to see it from different frame of references. Time runs different for different people, in appearance.

General theory of relativity is the theory of gravitation. General theory of relativity have confirmed gravitational waves, gravitational lensing and an effect of gravity on time known as gravitational time dilation. Gravity affects the flow of time in General Relativity.

Einstein described gravity as the curvature of space time due to the object’s mass and density. That works very well in large scale cosmic world.

Time goes slow near gravity and at black hole it stops completely. In general relativity, bodies always follow straight lines in 4-dimensional space time, but they appear to us move along curved path in 3-dimensional space. The curvature of a space-time increases the straight-line distance and to keep the speed constant, time has to be increased.  It’s taking more time to cover the distance from A to B, now. Thus, time increases or runs slow near gravity. 

Einstein’s Special Theory of relativity is all about what's relative and what's absolute about time, space, and motion.  Special Theory of Relativity applies on Inertial frame of reference. The object which is not accelerating. For an acceleration, there is a General Theory of Relativity where gravity plays a major role. In an Inertial reference frame, object is either stationary or moving with a constant velocity in a straight-line path. In a circular movement, object starts acceleration because there is a centripetal force working outwards that changes the speed of an object.

According to Special Theory of relativity, Speed of light is constant everywhere. All observers will measure the same speed of light regardless of their motion.  A light year is the distance travelled by a light in 1 year. The speed of light in vacuum is approximately 3,00,000 km/sec. It is also the speed of all mass less particles travel in vacuum, including photons, electromagnetic radiation, and gravitational waves.

Length Contraction

When object approaches speed of light its relative mass increases but it doesn’t change its gravitational attraction. Gravitational attraction depends on the rest mass.

According to E==MC^{2 ,} when the object attained the speed of light, it needs an infinite amount of kinetic energy.  When object moves with speed of light, its mass increases to infinite which provides infinite amount of energy to an object.

E==MC² , Infinite mass is converted to an infinite energy!

When an object approaches speed of light, it’s length start contracting and as it reached to the speed of light it becomes a point. Length contracts in respect to an observer, in an alternate way it’s relative length is short. For a point like object, distance doesn’t exist. Distance become zero so the time taken is also zero. That’s why they say, you can travel past, present and future in some imaginary time machine!

In this process, momentum also reached to infinite as per the equation P==mv, where m is the mass of an object and v is the velocity.  M is the relative mass of an object, which is approaching the speed of light.

The momentum of a particle is a measure of the time required for a constant force to bring it to rest. When the object is moving with an infinite energy, it never gonna rest in any time. So, the momentum is also infinite, which always make it keep moving.
https://www.youtube.com/watch?v=a8Vssy0pEpI


To be continued

Illusion of Time: Twin Paradox, Time Dilation, Gravity, Time Travel

Let’s come to the other very interesting phenomenon of Time Dilation. Time runs different for different people! It seems different for different observers, however most of the time we forget that time is just the distance travelled in space.  Let’s delve into it more:

2-star ship, 1 in motion and 1 in rest.  Both the ships fire a laser beam to the target. The moving ship fire a laser light when it passes through the stationary ship. According to Einstein, the speed of the laser light doesn’t depend on the motion of the ship, so we see both the beams travel side by side at the same speed. The laser beam from the stationary ship would travel more distance and therefore it takes more time to reach the target. Distance from a source to target for a moving ship is very less.

To make the speed same for both the ship, we need to change in distance and time. Speed is the just the distance measure in a time.

Speed==Distance/Time

For a moving ship the distance covered is 3 km and time taken is 1 sec for a light beam and for a stationary ship, the distance covered is 6 km and time taken is almost double the moving ship. For a stationary ship 2 sec are passed to hit the same target. 2 sec are taken by a stationary ship to hit the target which was hit in 1 sec by the moving ship.

Moving clock appears to run slow!

Twin Paradox

Imagine, on Earth there two twins. There is a space rocket travelling with the speed V, which is nearer to the speed of light. One twin sits on the space rocket and travel all along for the period of 5 years with the velocity V. He travelled a total distance of 3 light years in 5 years. He then takes a return journey to his twin brother, on the earth. He takes another 5 years to return to the earth with the speed V. They reunited after 10 years.

The twin on the earth doesn’t move in space; he only travel in time and that is 10 years on earth.  The other twin on space craft travel to the space and then return back to the earth. The total distance he covered was 3 light years in 10 years period. The moving twin covered the more distance in the same time period. Thus, it appears his clock moves slow and he gains ageing late. Though, the time spent is the same for both of them. One gains many accomplishments, knowledge and wisdom in less age while the others take whole years of life and don’t reach near to him. Some surely do time travel in life!

In ancient scriptures, I Human years== 1 Divine day (day & night) and 360 divine days ==1 Divine years.  When humans complete 1 years, Devas complete 1 day. That’s why they appears to us immortal!

When you are detached from this 3-dimensional world, you reached to the higher dimension, out of this space-time. You have the clarity of life and its events which helps you to join the dots of past, present and future. According to scriptures, there are 7 Lokas existed between Earth and the Sun and ultimate aim of every soul is to reach the Sun. Sun is the Atma, the energy of the source of creation. This is the first energy or vibration that occurred in eternal ocean of time. Incapable in deciphering, this was the timeless state of nothingness.  Brahman, Hirayangarbha or Mahakala is that ecstatic, eternal and blissful energy state which is all pervading.

Ancient scriptures say about the elementary particle composition of this “Universe”. “Sun and the rest of the universe are woven in string. What is that string that is Vayu.” Vayu that take the shape of every object in the universe. Vayu is not simple English air; in Vedic Sanskrit Vayu means which is all pervading. The whole universe is woven in a string. At elementary level, particles are associated with each other. These are the different combinations of energies which forms matter particles of this universe. There are 73% of energies are unmanifested, incapable to decipher in the present scenario. Needs enormous amount of temperature and pressure to create disturbance at energy level. 

Principals of nature remain constant everywhere. Nature changes other variants to make its laws constant. One Major principle of nature is first you see the cause and then see the effect. It applies on whole cosmos.

Let’s take an example for better understanding. If there are 2 stars A and B. A is 10 lightyears farther from an observer and B is 3 lightyears. If some event occurred at A and after a year another event occurred at B, which event we would see first? Event B would reach us before because it’s only a 3 lightyears father. Event A is still travelling and it’s still 6 years to see that event.

What happen if one event caused another event to happen? Can you see later event before you see the former?
The answer is No.  The event of A causes the event on B to happen.  Light from A comes direct to us. Event B doesn’t happen until the information for the causes arrived from A. The light cannot travel from A to B and then reaches to us.  So, you cannot see the effect happened on B before the cause reaches to it from A.

Take a journey to an ultimate quest of life: Time