## Background

I had explained here, thermodynamic concepts of Energy, Entropy and Second law of thermodynamics using the Shiva, Ganapati and Skanda story.

Now let me explain the Zeroth law of thermodynamics using the story of birth of skanda, the heat.

## Skanda, the heat

Skanda means hopping up and down. It is the random motion possessed by all sub-atomic particles in nature. This radmon up and down oscillatory motion is what we perceive as heat.

How is this heat or Skanda produced..?

## Potential and Kinetic Energy

Shiva is Energy in which the Universe lies. But in the world see, the classical world,  matter dominates. We see only matter everywhere.

In this classical matter world, Energy becomes a subtle property of matter. In all matter forms, energy exists as potential energy and kinetic energy.

In sanskrit, a subtle form is called sUkshma. Feminine gender is used to indicate such subtle or sUkshma. Hence these two energies Potential and Kinetic energy are depicted as two 'wives' of Shiva, the energy.

## What is Potential Energy..?

Potential energy is the energy that 'raises' high in the matter by virtue of its position, charge, electromagnetic bonds within the matter etc etc.   Potential energy resides 'high' in the matter and can be used to produce work or Heat.

In sanskrit, parvata means 'hill' or  'height' (1).  pArvati means female who is from the Heights or Hill. pArvati is this potential energy that raises in matter, resides High, produces Work (the Ganapati) and Heat (the Skanda).

Parvati (the potential energy) is depicted as sitting besides Shiva, the Energy.

## What is Kinetic Energy..?

The potential energy in matter can produce Work and Heat. Work is macroscopic ordered movement (Ganapati) of matter. Heat is microscopic random movement (Skanda) of matter. Kinetic energy is the energy in both these movements.

In sanskrit, Ganga means 'moving (ga)-moving (ga)' or 'going-going' (2). The energy in this going-going or moving-moving is Ganga, the Kinetic energy.

Ganga, the kinetic energy, is depicted as river,  rising and flowing from Shiva's matted-hair-locks.

## The transfer of energy between matter

Energy not only produces movement of matter in terms of Work (macroscopic movement) and Heat (microscopic movement), but these movements can also be transferred between matter.

A matter form can acquire these movements (Work and Heat) from another matter form. That is called transfer of energy between matter.

Let's look at the case of a gas-stove heating up a pressure-cooker.

At first there is 'energy' (Shiva) in the gas cylinder. This energy is the potential energy. This energy is not transferable.  We light-up the gas stove. This starts a chemical reaction in which the gas burns using air. Now the energy is transferable (Agni).  Potential energy becomes Kinetic energy.

The kinetic energy (ganga) of gas particles transfer energy (Agni) in the gas to Vessel. The particles of vessel acquires microscopic random movement or heat due to transfer of energy, the Agni, by the kinetic energy (ganga) of gas particles.

So Skanda, the heat is born in the Vessel, when Energy in gas (Shiva), becomes transferable (Agni), flows through as Kinetic energy (Ganga) of gas particles and reach the vessel.

In the Puranic stories, this is depicted Shiva's sperm spilling over, becoming Agni, flowing through Ganga, and reaching a destination pond.

## Six ways of Heat production

How is heat born in a destination object..? Heat, the microscopic random movement of particles of a destination objected, is born in that destination, when energy from some source becomes transfeable, flows through as kinetic energy and is imparted/transferred to the particles in the destination object..

There are six different sources of energy that can impart microscopic random movement on particles of matter.
1.  Particles can absorb Electromagnetic radiation and produce heat.
2. Chemical reactions that lead to breakage/formation of electromagnetic bonds release energy that imparts particles with heat
3. Nuclear reaction that lead to breakage/formation of Strong force bonds release energy that imparts particles with heat.
4. Movement of Charged particles in electric field can produce heat
5. Movement of Charged particles in alternating magnetic field can produce heat
6. Physically moving particles by gravitation or manually, for eg compression,  can produce heat.
All heat production sources in Universe can be classified into one of the six above.

These are the ONLY six different ways 'heat' can be produced. They are Absorption of light, Chemical reaction, Electric current, Physical movement, Alternating magnetism and Nuclear reaction.

These six are six different 'skins' for 'heat'. But the 'heat' is only one.

In Sanskit, krtti means ' a skin' or 'covering'. There are six different 'skins' for 'heat'. There are six different ways in which 'heat' can be clothed. These six different ways are depicted as six 'krttikas' or six mothers that nurture Skanda, the heat, in Puranic stories.

Though there are six different ways in which heat is clothed, internally the 'heat' is only one, which is, it is simply a microscopic random movement of particles.

## Zeroth law of thermodynamics

The zeroth law of thermodynamics has many forms. All of them convey one message. There is only one heat thought it might have appeared in six different forms. Temperature is one-dimensional. We can arrange bodies 'heated' up from 'hot' to 'cold' linearly irrespective of the method by which they are heated.

A body might have been heated by radiation. Another one by friction. Another by pressure or magnetism or flow of charges or chemical reaction. All of them produce only one heat measured by one temperature.

Hence in Hinduism, Skanda, the heat is depicted as one person with six faces.

-TBT