The ‘sluggish’ photon

The 'sluggish' photon
Sunlight is a wonderful thing
it keeps us warm
and provides energy for plants and animals.
We consider sunlight the primary source of life on Earth.
Physicists can describe its properties quite accurately.
Essentially, it is a form of electromagnetic radiation
which comprises particles called photons
that spread like waves.
A photon of sunlight is a by-product
of the nuclear fusion process
that takes place in the sun.
There is extreme pressure inside the core of the sun,
as a result of which
hydrogen nuclei fuse
and turn into helium nuclei.
The mass of these new nuclei is less
than that of the hydrogen nuclei,
and this difference in mass
transforms into heat
and radiates from the sun
in the form of photons.
The photon is the fastest particle in the universe.
If nothing blocks its path,
it travels at 300 million metres per second
This is called the speed of light.
At that speed,
it takes 8 minutes for the photon to reach the Earth
from the surface of the sun.
Interestingly, the sun's rays heating the Earth today.
were generated a long time ago,
before the last ice age.
What happened during that period?
Well, the reason it arrived so late
is that a photon
cannot travel in a straight line
in a dense medium;
it always hits something.
The core of the sun is so dense
that the photon cannot cover even 2 cm
without hitting another particle.
It is as if the core of the sun were a pinball machine
and one game lasted hundreds of thousands of years.