Introduction
Time is a dimension designed by human intelligence to measure intervals in the sequence of an action, process, or condition, or to measure productivity or schedule activities universally. Time is a linear dimension in the temporal realm. It marks temporal distances like inches on a ruler. Measured time based on physical methods is relative to physical characteristics. Time is important in defining the speed, rate, and rate of change of processes.
History
Carvings of the moon’s phases have been discovered on bones dating back over 20,000 years. During that period of human history, hunters needed to know how long they had been away from their camp, making the moon their choice to track the passage of time. For millennia, humans used objects in the heavens to count the passage of time.
While seasonal time was valuable for many activities, it became apparent that resolving time in smaller increments would be beneficial. Methods were developed for tracking the hours on water clocks, hourglasses, and sundials. There were limitations to these methods. Water froze in the winter, hourglasses needed to be turned over, and sundials were of no use after sunset.
Early intelligent life on Earth regarded celestial bodies with awe and fascination. People observed the stars to discern patterns and cycles influencing growth and seasonal changes. The moon became a vital tool for tracking the changing seasons, while the sun marked productive intervals.
In the first century BC, due to the confusion between 354+ day lunar and 365+ solar years, Julius Caesar chartered Sosigenes of Alexandria to come up with a more accurate method. He replaced the old lunar calendar with one that used the sun to delineate the year, ignoring the moon. This Julian calendar implemented leap years, adding one extra day every four years. This was not quite perfect.
By the 16th century, the Julian calendar was also out of step with the seasons. Pope Gregory XIII implemented updates in 1582 that dictated leap years be skipped on years divisible by 100 except when divisible by 400. Two thousand years later, the whole world still uses Sosigenes’ modified calendar.
Around AD. 1000, mechanical devices that could ring bells to tell time began to appear in Western Europe. The word “clock” derives from the French, “cloche,” meaning bell. Within a few hundred years, dials were added to visually show the hour. By the 13th century, astronomer monks were creating complex movements with dials that had an hour hand and displayed moon phases, the solstices, equinoxes, and more.
As astronomy advanced, however, more precision was needed. This came courtesy of the regular motion of swinging pendulums. In 1657, the Dutch astronomer Christian Huygens applied for a patent for a clock using the oscillation of a swinging pendulum to regulate the passage of time. Clocks were now accurate enough to justify not only an hour and minute hand but a second hand as well.
In 1676, the Greenwich Observatory was built outside of London with two pendulum clocks. These clocks were accurate to within 10 seconds a day. With these new clocks, astronomer Sir John Flambeed, showed that the spinning of our planet was, in fact, constant. This provided the first link in the efforts to solve the longitude problem.
By the 18th century, navigators were using portable clocks driven by wound springs that could accurately maintain Greenwich time. By comparing them to their observed local solar time, they could determine their longitude. Mechanical timekeeping devices became common. The problem became one of synchronizing them. Differences in local time did not present a problem, as every town adjusted its clocks to the local sundial.
With the arrival of trains, all of this changed. For every 15° of longitude, the local solar time changes by one hour. While cumbersome in small countries, it was a real problem in the United States, where transcontinental railroads spanned a time difference of three and a half hours. Each town used local sundials to set their clocks, while each railroad had a different standardized time for their published timetables. This made it almost impossible to have rail schedules that made any sense at all. To solve this, astronomers divided the globe into 24 time zones. The starting point for these time zones was based on the meridian defined by specific observatories that made noonday observations.
The next step in the synchronization of time was the adoption of standard times for each country. In 1833, the Greenwich Observatory installed a bright red “time ball” mounted to a mast on the observatory roof. The ball drops at precisely 1 p.m. every day, allowing ships on the River Thames to set their chronometers in reference to the observatory clock.
As telegraphs encircled the globe, it became possible to transmit time signals. Daily time signals were being sent across England by the 1870s. In America, astronomers also began to distribute time. The U.S. Naval Observatory sent occasional time signals as early as 1865.
By the late 19th century, the situation had taken on international dimensions. In 1884, delegates from around the world gathered in Washington, D.C., at the International Meridian Conference to determine “a common zero of longitude.” Each of the world’s 24 time zones would be calculated from a single prime meridian and standardized to mean solar time. Thus, the beloved sundial was relegated to gardens and church cemeteries. The meridian of the Greenwich Observatory was chosen as the zero point for the world’s time zones.
For easier interval calculation, a calendar was started using days. Astronomers and software use this to quickly calculate the number of days between events. The Julian date is the number of days that have passed since noon on January 1, 4713 B.C. In 1957, the Smithsonian Astrophysical Observatory created a modified Julian date, which begins at midnight GMT on November 17, 1858. This made the day’s count considerably smaller and more manageable for early computers.
With astronomy, calendar dates are not useful as the stars run at a different time based on their position in the heavens over the year as they do not go around the sun. Sidereal time (as a unit also called sidereal day) is a timekeeping system that astronomers use to locate celestial objects. Using sidereal time, it is possible to easily point a telescope to the proper coordinates in the night sky. In short, sidereal time is a “time scale that is based on Earth’s rate of rotation measured relative to the fixed stars,” or more correctly, relative to the March equinox.
Classical time
In classical physics, time is a scalar quantity of measurement, a fundamental quantity like length, mass, and charge. Because activity progresses in only one dimension, a negative value for time is only used when referencing one activity to another in time. Time progresses regardless of its relationship to spatial dimensions.
Time marks the indefinite and continued progress of existence and events in the past, present, and future. As such, time is an endless dimension. It does not have a start (zero) or end.
Time has evolved into a non-spatial continuum that is measured in terms of events that succeed one another from the past through the present and into the future. Time implies action. Any physical value or parameter with a change in its derivation implies that time is involved.
Since time is a man-made construct, it is designed to be a constant like meters or grams, marking activity rather than physical attributes. It is used to mark progress or the location of events within the universe. As a location marker, it becomes an important dimension.
Time exists in nature, but the objects involved are oblivious to its passage other than a bit of tugging or rhythmic motion that may occur (seasonally) as a result of other objects. Logically, it is unlikely that inanimate objects care about the concept of time.
There are three popular time scales:
Sidereal time relates to the earth’s position among the stars. Calendars are based on the first thing used to connect human activities at this point in time. A secondary use was navigation using celestial bodies. It is used in astronomy to point telescopes beyond our solar system.
Solar time refers to the passage of time related to the position of the sun in the sky. This time is measured by a sundial. It is used to mark and coordinate activities on earth. As a precise timekeeping method, it has limitations due to seasonal variations. Due to the earth’s orbit around the sun, the length of each day varies from -21 to +29 seconds.
UTC time Is a human-controlled, constant interval time based on accurate intervals from molecular oscillations. UTC time is periodically adjusted to synchronize with solar time (leap seconds and years). UTC is normally used in a 24-hour-per-day format, although it is the reference for earthbound commerce clocks, which are 12-hour clocks in various time zones to reflect local convenience.
Relative time
Einstein, in 1905, proposed his “Special Relativity” theory on the relationship between space and time. The theory transformed theoretical physics and astronomy during the 20th century, superseding a 200-year-old theory of mechanics created primarily by Isaac Newton. It introduced concepts such as four-dimensional spacetime as a unified entity of space and time, simultaneity relativity, kinematic and gravitational time dilation, and length contraction. Much of what Einstein explained was based on the concept that time is a variable. This introduces physics to a new paradigm in which the speed of energy must be constant rather than changing with time. We have lived with this theory for the past 117 years.
Einstein’s “Special Relativity” theory revolutionized our understanding of time, introducing concepts such as four-dimensional spacetime, simultaneity relativity, kinematic and gravitational time dilation, and length contraction.
Deciphering the Cone of Time
From the observer’s perspective, time unfolds as an infinite flat plane, stretching endlessly along the timeline. However, for charges traversing the temporal boundary, the perception of time takes on a different form. Imagine this boundary as a cone, tilted at a 45-degree angle from the perspective of charges passing through. In this analogy, charges interact with time in a manner reminiscent of navigating a cone-shaped surface, with their trajectories influenced by the angle of entry and the dynamics of time itself.
Temporal Interaction of Charges
As charges traverse the temporal boundary, their angles of entry play a crucial role in determining their behavior within the temporal realm. Charges entering the temporal boundary at angles below 45 degrees may encounter limitations, akin to diffraction phenomena, leading to a phenomenon where some charges fail to penetrate effectively. This observation suggests that the temporal boundary may exhibit impedance or dielectric properties, influencing the interaction of charges with time. Furthermore, the concept of the “cone of time” implies a finite limit to the temporal extent of charges, beyond which they are returned to their origin.
Quantum Time
Quantum mechanics revolutionized physics in the first half of the 20th century, and it still represents the most complete and accurate model of the universe we have. Time is perhaps not as central a concept in quantum theory as it is in classical physics, and there is, as of yet, no such thing as “quantum time.” For example, time does not appear to be divided up into discrete quanta, as are most other aspects of reality. However, the different interpretations of quantum theory (e.g., the Copenhagen interpretation, the Many Worlds interpretation, etc.) do have some potentially important implications for our understanding of time.
Understanding the origin of time in any of the following discussions is essential to understanding the mathematics involved. Each of the mechanisms represents a process, not a state. Since processes take time, a reference for each must be set. Using the idea that photon dipoles borrow energy from a hole (energy from the past), it is defined that this past exists only within 1/4 of a wavelength of the center or 1/2 wavelength from the leading edge of a process. This essentially defines the field in which a single energy dipole exhibits energy coupled to its source, while the artifacts of a process may linger for longer as waves. The immediate use of energy sources can only be within the near-field frame. The exact nature of the origin of time is determined by the position of the charge in the photon dipole, which dithers as the dipole rotates.
Conclusion
The exploration of time spans across millennia of human history, scientific inquiry, and philosophical contemplation. From ancient methods of tracking celestial movements to the development of precise timekeeping devices, humanity’s understanding of time has evolved significantly. Classical physics conceptualized time as a scalar quantity, independent of observers, while Einstein’s theory of relativity introduced the revolutionary notion of spacetime, where time is intrinsically linked to space and gravity.
Furthermore, the advent of quantum mechanics has reshaped our perception of the universe, although the concept of “quantum time” remains elusive. Despite its absence as a discrete quantized entity, quantum theory presents profound implications for our understanding of causality and the origin of time.
Overall, time emerges as a multifaceted dimension that transcends classical boundaries, permeating every aspect of existence. Whether viewed through the lens of classical physics, Einsteinian relativity, or quantum mechanics, time remains a fundamental cornerstone of our understanding of the cosmos. Its enigmatic nature continues to inspire curiosity, challenge assumptions, and drive scientific inquiry into the deepest mysteries of the universe. As we unravel its complexities, we gain deeper insights into the very fabric of reality and our place within it.