Throughout almost the entire history of mankind, outstanding physicists and philosophers have tried to comprehend time. However, it remained completely misunderstood. And humanity, instead of understanding its nature, has learned to at least measure it. How does the countdown, from which point it is conducted and in what order? Let's find out more about it.
What is time
Before dealing with the measurement of temporality, it is worth refreshing your knowledge about this concept. Time is a measure of the duration of the existence of all objects and creatures in the Universe from the moment they appear to disappear. In fact, this concept is a kind of marker for determining events.
In classical physics, there is such a concept as the "axis of time." In it, this phenomenon is considered as a one-dimensional straight line moving from the past, through the present, into the future.
It is believed that the concept of "time" arose at the time of the birth of the universe, due to the Big Bang. It is not yet possible to refute or confirm this assumption.
Time properties
Like any value, this one has special properties:
- One-dimensionality.
- Irreversibility. In other words, time does not just move in a straight line, but it does so only in one direction (from the past to the future). If we take 2 arbitrary points on the temporal axis, then one will certainly be the future relative to the other. And that, in turn, will be for the first past.
- Homogeneity. It consists in the equality of every moment. The so-called initial longing for the countdown is just a convention. Since practically any event can begin a new temporal calculus.
- Objectivity. Time exists, regardless of the consciousness of man and from his acceptance of this phenomenon. It's like with the law of universal gravitation: although for many centuries mankind did not know about its existence, it still continued to operate.
- Universality. There is and cannot be anything existing outside of time.
What is called a countdown
Despite the fact that the phenomenon in question has homogeneity, throughout the history of the world, people have tried to find a way to learn how to count it.
The fact is that every civilization at a certain moment of existence noticed a change of seasons. For the sake of survival, its representatives were faced with the need to learn how to calculate the arrival of favorable and unfavorable periods of time in order to make advance reserves and not die from hunger and cold. So the chronology arose.
Calendar, its types and history
This word from different nations looked and was written in different ways. However, its meaning has always been one. A calendar is a kind of system (order) for counting large periods of time. It all started small.
The first recurring cycle that a person noticed was a change of day and night - a day. Gradually, it was noted that at regular intervals the moon passes through all phases. A little later, people noticed that after 12 moons the seasons are repeated, that is, a year passes. Based on these observations, the lunar calendar was invented. According to him, the year consisted of 354 days.
Unfortunately, this order of reference for large periods of time did not coincide with the solar year. Therefore, the peoples who used it had to go to different tricks in order to correct inaccuracies. For example, the Romans once every 3 years inserted an extra month - marzedonia.
In some modern countries , lunar calendars are still used.
The people of Ancient Egypt, who worshiped the sun god Ra, based their chronology on the movement of the sun, not the moon. However, such a system was also far from perfect, since the number of days in a year exceeded 365. In later eras (when the country alternately fell under the rule of the Greeks, then the Romans), the new owners of the state tried to introduce amendments to the Egyptian solar calendar, but they did so until the end and didn’t take root.
The Greeks had a special order of reference for large periods of time. It was called Metonov cycle and lasted for 19 years. This system was developed by astronomer Meton in the 5th century. BC e., took into account the movement of both the Sun and the Moon. Despite its complexity, it was fairly accurate and progressive for its time. It is worth noting that the Jewish people still use it. In addition, the time of Easter is calculated annually according to this principle.
The Romans, who granted their entire system of chronology to the whole Christian world, at first had a very awkward calendar, consisting of 10 months. However, Julius Caesar carried out his reform and introduced a new frame of reference for years. After the death of the emperor, his followers became a little confused in the new calendar, because of which he accumulated 4 leap years more than expected, and Octavian Augustus was forced to cancel them for as long as 16 years.
After Christianity became the main religion of Rome, with its spread around the world, many countries switched to the Julian calendar.
It was just that it was not perfect, and after several centuries the confusion with leap years led to the fact that the actual time interval between the spring equinoxes (the year was considered by them) did not coincide with the calendar.
In this regard, the head of the Catholic Church, Pope Gregory XIII in 1582, together with the mathematician Aloysius Lily created a new system of chronology, which is used by the whole civilized world today.
Chronology
The order of reference for large periods of time is inextricably linked with such a concept as chronology. It is formed from the Greek phrase “doctrine of time” (from the words “chronos” and “logos”). From its etymology it is clear that this science specializes in the study of time and how to measure it. It is divided into 3 types:
- Astronomical. He specializes in studying the motion of celestial bodies. Based on its cyclical nature, it helps to calculate the exact astronomical time.
- Historical. Unlike the previous one (which aims to establish the exact time), this one focuses on the study of calendars and timekeeping systems of different civilizations and states. It also helps to synchronize the chronologies of different peoples in order to know exactly when an important event occurred.
- Geochronology. He studies the time according to the state of the geological rocks of the Earth. This industry has its own geochronological timeline. The origin of the time on it is the moment of the formation of our planet, approximately 4.6 billion years ago.
Time reference
Since each great civilization had its own calendar and chronology, it is worth paying attention to the beginning of its reckoning. Although, in practice, time is a homogeneous phenomenon, each reference system has its own starting point.
The Egyptians chronology was carried out from the beginning of the reign of the next pharaoh or the whole dynasty. In the Roman state, the starting point was the date of foundation of Rome. In the modern world, most chronological systems are based on some important religious events. For example, in Christianity this is the estimated date of the birth of Christ, among Muslims - the time of the passage of the Prophet Mohammed from Mecca to Medina, among the Buddhists - the time of the death of the Buddha, and among the Jews - the time of the creation of the world (in their opinion).
Minimum calendar time intervals: day, week, month
Having dealt with the starting points of the chronology, it is worth considering the most important units that are used by all of them.
The minimum period of time used in all calendar reference systems is a day (day and night, last 24 hours). This concept refers to the period of the complete revolution of the Earth around its own axis.
Subsequently, weeks are formed on the basis of this unit. In the modern world, they last for 7 days. However, this has not always been the case in the past. For example, the Slavs this period of time was 9 days, and during the USSR - 5, and sometimes 6 days.
The ancient Egyptians had a week of 10 days, and Maya - of 13 (sometimes 20).
Next in ascending order is the month. Initially, this was the period the moon passed a full revolution around the earth. However, today it does not necessarily coincide, at least in the Julian and Gregorian calendars.
Quarter, season
Months are impoverished in seasons and quarters. Each season (it is the same time of year) consists of 3 calendar months. There are 4 of them: winter, spring, summer and autumn. The quarter also consists of 3 months, but they are not counted according to the seasons, but strictly according to the calendar. This unit is highlighted in order to make reporting easier.
Year and its varieties
Months, quarters and seasons form a year. This is the first large period of time during which the Earth makes a complete revolution around the Sun. It consists of 12 months, 4 seasons or quarters.
The traditional Christian year consists of 365 days, but every 4th is a leap year, and it has 366 days. In Jewish and Islamic calendars, it consists of 355 days.
Also, one should not forget about such a concept as a school year. This is a period of 9 months during which classes are conducted in educational institutions.
Century, millennium, megagods and gigagods
100 years form a century or a century. This is one of the largest periods of time in relation to a person, since only a few are able to live so much.
The millennium consists of 1000 years, or 10 centuries.
It is also worth knowing what the period of time is called the largest relative to the reckoning. This is gigagod; it consists of 1,000,000,000 years. In addition, an intermediate unit is allocated - mega-years (1,000,000 years).
Megagod and gigagod are not used in historical chronology, since at the moment there is no evidence of the existence of intelligent life in these periods. However, they are important for geochronology.