On the nature of time – Basudeba Mishra
Time is considered as the aspect of the physical universe, which, at a given place, orders the sequence of events. Also, a designated instant in that sequence is called time – technically known as an epoch. But does it really exist? If so, does it have a physical presence like the objects of daily use? Can we use it in equations?
Everything we perceive has contradicting characteristics. They are constituted of a few fundamental objects that change consistently. Even the quarks change flavor continuously. But there is a consistency within such change that remains. That consistency makes up for protons, neutrons, atoms, molecules and everything that we see and use. These can be characterized by nomenclature, form and charge (interactive potential). Thus, everything can be divided into two categories: those non-changing existence beyond space, time and coordinates – called Aabhu (आभु – आसमन्ताद्भवति); and those with ever changing existence, but used as if they exist in space, time and coordinates – called Abhwa (अभ्व – अभूत्वा भाति). But they are never separate. Aabhu contains Abhwa and vice versa (अन्तरं मृत्योरमृतं मृत्यावमृतमाहितम् – शतपथब्राह्मणम् 10-5-2-4). A particle is not a wave, but it always moves in a wave. This duality can’t be divorced.
All the objects we see and use like earth, water, air, etc., are constituted of fundamental particles that have physical existence – they are directly perceptible to our sense organs. Hence they are Aabhu. But terms like number, dimensions, density, color, mass, charge, parity, etc., have no separate existence from the object they are related to. They are apparent – Abhwa. These are special aspects of the object that differentiates it from others aspects. Time, space, etc., belong to the category of non-physical, but eternal – hence Aabhu. They are mental projections only.
Thousands of years ago, Prashastapada of India had defined time as: परापरव्यतिकरयौगपद्यायौगपद्यचिरक्षिप्रप्रत्यय लिङ्गम् – time is the non-physical cause that generates the perceptions of sequence and interval (परापरव्यतिकर), simultaneity and divergence (यौगपद्य-अयौगपद्य); and instantaneous and long-term (चिरक्षिप्र). Though each of these perceptions are different, the cause for such perceptions is same. That common cause is called time (काल). Everything comes into existence (time of creation or origin) and finally gets destroyed (time of cessation or destruction) only in time. Hence time is said to be a cause for the existence of everything.
Mathematics is the quantitative aspect of reality, which is the process of conversion of one to many and vice-versa as well as many to other many through linear or non-linear accumulation and reduction. Number is a characteristic of all objects by which we differentiates between similars (द्रव्येषु भिन्नत्वव्यवहारः पृथक्तातिरिक्तभेदवशात् संख्यावशाच्च). An object can be perceived only through the differentiation of its inherent structure that determines its form and interaction potential with others, and its position from other similar objects (आन्तरालिकावयव संस्थानगतभेद). Number causes the perception of differentiation among objects (भेदगणनाकत्मकत्वम्). When we cannot differentiate the object from other similar objects, we call the object as one (एक). If we can differentiate, we call them many (बहु). Many can be 2,3,4, ….n (not infinity) depending upon the quantum of sequential differentiation.
Time is perceived uniformly in everything. It is without similars. Hence we can assign number one (1) to time. Since simultaneity or otherwise is uniformly perceived everywhere, it is not many. Infinity is like one – without similars, but with one difference. While the dimensions of one are clearly perceptible, the dimensions of infinity are not perceptible from any direction. Since the dimensions of space and time are not perceptible, they are infinite. There are only four infinities: space, time, coordinates and information. Infinities coexist. Hence, they exist as space-time.
We differentiate objects by their forms (दिष्टि प्रस्थ सुवर्णादि मूर्तिभेदाय कल्पते), time by the effects (क्रियाभेदाय कालस्तु) and number by all types of differentiation (सङ्ख्या सर्वस्य भेदिका). We differentiate actions by time (कालात् क्रिया विभज्यन्ते) and space by the objects (आकाशात् सर्वमूर्तयः). Creation, existence (time evolution) and final dissolution etc., is caused by time (उत्पत्तौ त स्थितौ चैव विनाशे चापि तद्वताम् । निमित्तं कालमेवाहु विभक्तेनात्मना स्थितम् ॥). Even though everything is interlinked and interdependent, we differentiate between them following the above principle (एतावांश्चैव भेदोऽयमभेदोपनिबन्धनः). This time evolves cyclically in six stages, which exhibit their separate functions (सैव भाव विकारेषु षडवस्थाः प्रपद्यते । क्रमेण शक्तिभिः स्वाभिरेवं प्रत्यवभासते).
Time – कालः, has two meanings: motion and counting (कलँ गतौ॑ स॒ङ्ख्याने॑ च). Thus, we use the same time in two different ways. One which eternally flows (अक्षय्यात्स्यन्दते यथा) in a straight line like a river (नदीव प्रभवात्काचित्) never to return (सोरुस्सती न निवर्तते), is the non-physical time (अमूर्तकालः), which flows at a constant rate. This is analog time. It cannot be counted, as we can count only finite objects. This time is infinite. Everything appears in it and gets transformed to a different form through a chain of intermediate stages (like eating, where something enters our mouth and after intermediate processing, goes out as excreta to mix with other elements to form different objects). For this destructive potential, it is called KAALAAGNI RUDRA (कालाग्निरुद्रः – लोकानामन्तकृत् कालः). Similarly, it is also associated with creation and existence.
The other is measurable time (मूर्तकालः), which is counted (कलनात्मक) as the interval between succeeding events (एवन्नानासमुत्थानाः), which is cyclic in the form of time evolution (कालास्संवत्सरग्गं श्रिताः). Time evolution cycle is the same for everyone and everything from atoms to the universe itself and from plants to bacteria to humans. It takes place in six steps (षडध्वा कालः) from:
1) being as cause (JAAYATE – जायते), to
2) becoming as effect (ASTI – अस्ति), to
3) transformation due to accumulation of harmonious others (VIPARINAMATE – विपरिणमते), to
4) growth due to accumulation of similars (VARDHATE वर्द्धते), to
5) transmutation (decay) due to accumulation of disharmonious others (APAKSHIYATE – अपक्षीयते), to
6) change of form due to disintegration and re-accumulation with others (VINASHYATI – विनश्यति).
This cycle continues. This is digital time.
The counting part (कलनात्मकः) comes from the fact that we use fairly repetitive and easily intelligible cycles (क्रियाव्यङ्ग्य) like the sunrise or its subdivisions or multiples as the units and scale up or down any interval we chose with reference to this unit. The ticks of a clock are harmonized to it. The so-called atomic time is not independent of the natural second, because the number of oscillations are determined with reference to the natural unit of second. Since the interval between hyperfine transition frequency in the microwave or electron transition frequency in the optical or ultraviolet region of the electromagnetic spectrum of atoms (of the caesium-133 atoms or ytterbium and strontium or hydrogen masers) is neither easy to measure nor are of equal duration, a large number of readings has to be taken and its average found to match the natural second. Thus, it is not a better system of time keeping.
Based on the difference in the intervals between events by which we perceive time, we can assign duration (digital segment or quantity) to analog time. Thus, we can connect time segments or separate them. Since time has these characteristics, it is an object. Since it has no beginning and no end, it is eternal. Time-reversal symmetry presupposes a direction of time and that is observed only as unidirectional. In algebra, we use negative numbers. Can we use negative sign to depict time? No. Negative number implies a transaction for exchange of something for something else. I had a dozen oranges. I gave it to someone for some consideration. Now I have -12 oranges. Though we use geometrical space-time for practical applications, we can’t transact time. We can reverse velocity, because it is related to space, but that will only be in forward time – a new event – not the reversal of the event. There is no time reversal symmetry.
When the tiniest of the charged elementary particle moves from the position occupied by it and completely moves out to the adjacent space (पूर्वदेशत्याग – उत्तरदेशसंयोग), the interval between these two events is known as the “instant” – क्षणः. It is so called because it is the minimum unit of time that is perceptible (क्षणः क्षणोतेः, प्रक्ष्णुतः कालः – प्रक्ष्णुतः प्रकर्षेण हिंसितः – हीनः – कालः). This is what some people call as the “time quantum” – the digitized version of analog time. The infinite sequence of such intervals is known as the “sequence” – क्रम. These two – movement from the position occupied by a particle and complete movement out to the adjacent space – cannot co-exist as the specific “unit of sequence” – क्रम – comes into play only after the “instant” – क्षणः. Thus, due to the temporal difference, they cannot co-exist. However, sometimes we use alternative symbolisms (विकल्पन) for describing objects that cannot be clearly delineated with speech-form-certainty (वस्तुशून्यत्वेऽपि शव्दज्ञानमाहात्म्यनिवन्धनो व्यवहारो दृथ्यते). Since the क्षण and क्रम cannot co-exist, yet we must perceive the different boundary conditions as sequences at the same temporal duration to have any meaningful perception of time; it must be described by an alternative symbolism. The alternative symbolism used for describing this combination of the instant – क्षण and sequence – क्रम is known as time – काल – literally meaning: that by which we measure intervals between events.
Usually, we can perceive only physical objects. Hence, is time an object? Time is no perceived like other physical objects. Hence, this time – काल is defined as: स खल्वयं कालो वस्तुशून्यो बुद्धिनिर्माणः शव्दज्ञानानुपाती लौकिकानां व्युत्थितदर्शनानां वस्तुस्वरूप इव अवभासते – Devoid of material content, mental construct and described through alternative symbolism, though, to people of less delineating mental capability, it appears as an object. The instant – क्षण has been described as क्षणस्तु वस्तुपतितः क्रमावलम्वी – displacement of object related and sequence dependent. The sequence – क्रम has been defined as – क्रमश्च क्षणानन्तर्यात्मा – infinite sequence of instants – क्षण. This leads to interesting conclusions.
Patanjali of India had defined past as अनुभूति व्यञ्जक – that which can be described with certainty from experience. Present is स्वव्यापारारुढ – that which is in operation. Future is भवितव्य व्यञ्जक – that which is indicative of what may happen. Fleeting present is the intermediate between non-present past and future. Patanjali describes ways to overcome the limitations of time and space.