In Jainism, the concept of time is cyclical and eternal, described through the doctrine of "Kālacakra" (Wheel of Time). Time is divided into great cycles called "Ārās." Each complete time cycle (Kalachakra) is divided into two equal halves:

1. Utsarpini (Ascending Half-Cycle): An era in which conditions in the world gradually improve—happiness, age, stature, and morality increase.
2. Avasarpini (Descending Half-Cycle): An era in which conditions gradually deteriorate—happiness, age, stature, and morality decrease.

Each Utsarpini and Avasarpini is further divided into six periods (Ārās):

1. Sukhama-Sukhama (Most Happy-Happy): An age of utmost happiness, prosperity, longevity, and morality.
2. Sukhama (Happy): Happiness still prevails, but slightly less than the previous era.
3. Sukhama-Dukhama (Happy-Unhappy): A mixed period, where happiness starts to decline, and unhappiness begins.
4. Dukhama-Sukhama (Unhappy-Happy): Another mixed period, but unhappiness is more pronounced.
5. Dukhama (Unhappy): Suffering and misery increase, happiness declines significantly.
6. Dukhama-Dukhama (Most Unhappy-Unhappy): The darkest age, with maximum suffering, minimum morality, and shortest lifespans.

Summary Table:

| Half-Cycle | Period Number | Name (Sanskrit) | Description | |-----------------|--------------|------------------------|------------------------------------| | Utsarpini | 1 | Sukhama-Sukhama | Most Happy-Happy | | Utsarpini | 2 | Sukhama | Happy | | Utsarpini | 3 | Sukhama-Dukhama | Happy-Unhappy | | Utsarpini | 4 | Dukhama-Sukhama | Unhappy-Happy | | Utsarpini | 5 | Dukhama | Unhappy | | Utsarpini | 6 | Dukhama-Dukhama | Most Unhappy-Unhappy | | Avasarpini | 1 | Sukhama-Sukhama | Most Happy-Happy | | Avasarpini | 2 | Sukhama | Happy | | Avasarpini | 3 | Sukhama-Dukhama | Happy-Unhappy | | Avasarpini | 4 | Dukhama-Sukhama | Unhappy-Happy | | Avasarpini | 5 | Dukhama | Unhappy | | Avasarpini | 6 | Dukhama-Dukhama | Most Unhappy-Unhappy |

Each full cycle (one Utsarpini + one Avasarpini) is called a Kalachakra and repeats infinitely. According to Jain cosmology, we are currently in the fifth era (Dukhama) of the Avasarpini half-cycle.

In summary:

• Time is divided into infinite cycles (Kalachakra).
• Each cycle has two halves: Utsarpini (ascending) and Avasarpini (descending).
• Each half has six periods (Ārās).

If you need more details about the characteristics of each era or their durations, feel free to ask!