The distinction of measuring the time in a scientific manner is achieved only by Bhāratīyas. Time has been measured from the smallest dimension to infiniteness. Even Time is envisioned as God and venerated. Paramēśvara was extolled as ‘Mahākāla’, the very embodiment of Time.
Nārāyaṇa Upaniṣad envisages Nārāyaṇa as ‘Kālaśca Nārāyaṇa:’, the very embodiment of Time, ages ago. The measurement of Time by Bhāratīyas is as ancient as the very God Himself. Count of many future ages has also been done even from very ancient times.
Since these calculations aren't dependent upon the birth & death of any individual, but are done based on astronomical science, they are thoroughly scientific. Unfortunately, during the British rule, the Bhāratīya way of Time measurement was casted as an illusion...
...with an evil intention to establish their command. Though it is 70+ years since independence, blindly time is still measured as BC & AD or CE in this religion-less land without even making any attempt to comprehend the magnanimity of Bhāratīya Time measurement methods.
Time measurement based on inhalation and exhalation : (image)