If Flash, the superhero, could travel at the speed of light, he could go
around the Earth 7 times in one second. But that is not the end of the
story, he will face some mind-boggling consequences. Here, we must make
it clear at first hand that this is completely a thought experiment
based on present real scientific facts. It is practically impossible for
anything having a mass to achieve the speed of light. We will also
explain why anything having some mass can’t reach the speed of light.
Thought experiment is the root of theoretical physics, and the speed of
light is fascinating one. Light is the key that unlocks our knowledge
about the universe and various weird phenomena in cosmology. The speed
of light is constant irrespective of any frame of reference and its
value is 299792458 m/s. Let us check out what happens if Flash will
travel at the speed of light.
1. His mass will increase to infinity
 |
| An object will gain infinite mass at the speed of light |
If an object will travel at extremely
high speed, it will gain mass. If an object travels at 90% of the speed
of light, then its mass would be 2 times its original mass. However,
when an object travels near the speed of light, its mass will increase
exponentially! If any object reaches the speed of light, its mass will
become Infinite. Infinite mass will need infinite energy for
acceleration, and providing infinite energy is impossible. Infinite is a
very big thing, it doesn’t matter how large amount of energy you
imagine, it will be still less than infinity. This is the reason that
anything having mass can’t reach the speed of light. Scientists have
been able to accelerate particles in Large Hadron Collider to 99.99% of
the speed of light. But still not achieved exactly the speed of light.
We know that light consists of photons, one can ask how photons can
reach that speed? The answer is very simple, a photon has zero mass.
Only for mathematical enthusiasts, here is the proof, Flash can’t travel at the speed of light.
The only way for Flash to move at the speed of light is that he should have zero mass.
 |
| For mathematical nerds, the reason flash can’t travel at the speed of light. |
2. Flash will face time dilation and time travel
 |
| Relative Time |
This is a real tricky one. We experience
a Newtonian form of time in our daily life, i.e, something flowing
smoothly and at a constant rate. But Einstein confirmed that time is
something relative, it is not constant everywhere. It may look difficult
to understand but actually, it is not difficult to understand, rather
it is difficult to accept. Time dilation is a difference of elapsed time
as measured by observers. Clocks on the Space Shuttle run slightly
slower than reference clocks on Earth, while clocks on GPS and Galileo
satellites run slightly faster. This effect arises neither from
technical aspects of the clocks nor from the propagation time of
signals, but from the nature of spacetime. The person traveling at
extremely high speed would experience a slowing of time. If a person is
traveling at 90% of the speed of light, his clock will be slow down by
half with respect to the stationary observer. The faster flash will move
with respect to the stationary observer, the more time slows down for
him. If he will achieve exactly the speed of light, time will stop
completely for him.
Again, only for those who are interested
in the mathematical way of understanding, here is the example that
provides an essence of time travel.
 |
| Time Dilation |
3. Field of view will drastically change for Flash
 |
| Field of view at the speed of light |
Near the speed of light, everything will appear to Flash as passing
through a tunnel-shaped window . Also, objects in front of him will
appear blue and the objects behind him will appear red. This is nothing
but the extreme situation of Doppler Effect. The spectrum of light waves
in front of him will crowd together, making the objects appear blue,
while the light waves behind him will spread apart and appear red.
After a certain speed, he would only see darkness because the
wavelength of the light entering his eyes will be out of the visible
spectrum.
4. Entire universe will shrink to zero for Flash
 |
| Stars |
Time will completely stop exactly at the speed of light for Flash. Flash
would travel billions of light years but still he will feel zero time
elapsed. Suppose two stars are there, star A and star B, 5 billion light
years away from each other. Flash will take billion years to move from
star A to star B from the point of view of an observer on the planet
earth. But for Flash time elapsed will be zero, he will reach from star A
to star B in zero time. The reason is that, at the speed of light,
length will appear shrunk to zero. He will experience that both star A
and star B are exactly at the same location, though they are billions of
light years away!
No comments:
Post a Comment