时间理论（Theory of Time）
Matter, space, energy and time, they are the fundamental parts in physics today, though their definitions and the essence are still perplexed for answers. Further interpretations of time in science and philosophy will make us more understanding of the world and the natural laws, and advancing the “theory of time” typically based on such an effort.
Seeking for the Truth of the Cosmos is the goal of philosophy and science. Philosophers need not know what the mathematical equation of the universe should be, but know the result computed by the expression; and it is not necessary for scientists to worry too much about “what-ism” they were sorted out, but necessarily realize that there are many useful thoughts and methods in philosophy.
Time plays an extremely important role in science and our lives. Controversies have been lasting for thousands of years, but the concept of time left us is still indefinite and partial. Though there were widely divergent views about its definition and its essence, time made no difference to our development in science and technology.
The discussions in the “theory of time” neither focused on the certain views assumed they might be wrong or different, nor aimed at those venerable people. The theory of time was founded on the basis of systematic research.
The achievements of modern science and philosophy provided the possibility to unveil the secret of time. Consequently my attempt was to classify the time, to tell what is “time” and what its essence should be, and, moreover, I was trying to point out some misconceptions of time. The classification of time, such as the species in biology, would be an important approach that made our researches on time become easily.
“Theory of time” provides this approach making you gradually learn the concept of time with many paradigms and diagrams. Some instances were repeated in order to enhance our understandings and memories, as well as to reduce our unnecessary speculation. However, you might deepen your comprehension with you own examples. It is hoped that you will view the time at a different angle. Meanwhile, the article is designed for all viewers who are interested in the field.
1. 客观时间(The objective time)
First of all, in order to avoid thinking too many abstract notions at the beginning, I would like to introduce you the “variety” of time step by step, which I thought somehow they are the “easily understandable” aspects of time. I knew every step was hard, and hopefully not so from now on. Take your time and read the article freely. Time might change everything. Now let’s start our “time travel”.
Time is divided into “objective time” and “subjective time.”
The Objective time: exists no matter whether there are observers or human beings.
相对论突出的贡献之一是提供给我们的“时空(space-time)”概念。有些相对论者认为时间不能独立于空间单独存在――空间是时间的主体，这个论述恐怕没有多少人愿意或有勇气去反驳，尽管有不少怀疑者。这里我做个小把戏，现在我们把一“空间”弄得与宇宙一样大，根据他们的理论，那么我们就找到了“宇宙时间”(the Universal Time)。其实，宇宙时间是亘古存在的，它伴随宇宙的存在而存在，而与小把戏(空间)没有任何联系(更多在第五部分)。
One of the notable contributions of Relativity is the notion of “space-time.” The relativists do not treat space and time independently—space is the subject of time, which nobody is willing to rebut at the moment. Thus I play a “trick”: Let us blow “space” as big as the Universe’ room, according to their theory, then we would find out the Universal Time. Actually the universal time has existed for a long, long time, and it will accompany the universal life throughout the whole evolution, and it does not matter with the “trick (space) ”(more in part 5).
As known, the Universe has past and present, and just because of this kind of change, it indicates the existence of the universal time. With the permission of science and technology, we could measure the universal time by “clock.” The universal time is an objective time, which exists no matter whether we named it or not, and I sorted it out into the part of “absolutely objective time.” The study of the objective times belongs to the scientific realm. So-called “the objective time” means time is a kind of existences, such as we can not see the Earth’s magnetic field which it can be measured by instruments; time, also, we can capture by the chronometers, i.e. time is not conceptive or imaginary “thing.” The objective time includes absolutely objective time and relatively objective time.
The absolutely objective time: includes the universal time and the bodies’ life-span.
The universal time is a progressive time, and a body’s life-span is an absolute quantity--an absolute period of time or interval, for instance, thinking about a star’s or a molecule’s life-span. Because we can not make certain when the universal time started, we are unable to utilize this time as a frame of reference (standard time) at the moment, but we might discover the absolutely objective time through the scientific calculation or observation, for example, scientists might find out when a star began and ended by means of the calculation or observation. If we want to know when we came into the world, it would be better to look up our birth registers; if our lives were considered to begin at the moment of the impregnation，we might have to expose our parents’ privacy. If we set the universal time as a frame of reference -- standard time, time is simultaneous at every point in the universe.
The relatively objective time: occurs by the interaction or relationship between two objects.
For example, the Earth moves round the Sun, thus there is a period between them. This period had existed for a long time before man’s appearance. I sorted this period out into the group of “relatively objective time.” Our ancestors discovered and made good use of this objective time, which created the solar calendar. The solar calendar or the Gregorian calendar was found based on the referential period of the Earth’s rotation around the Sun，and the period was given a man-made name and quantity – “year” (about 365 days). Actually “year” is a kind of subjective times which the followings will be discussed. It could be necessary to realize that the objective times could be used by man and they do not need the man-made concepts or quantities, like “year” or “365.”
2. 主观时间 ：由意识主体(人)或观测者参与所制定的时间。
The subjective time: to be constituted by observers or human beings.
Let us ignore the animals and the Aliens. The subjective time is a very important component in our lives, for example, we studied the origin, law, history; we built the Pyramids, traveled and worked, etc., it could be said that time involved in everything we did. The subjective time is a time system constructed by humans.
Isaac Newton’s “absolute time”, which was made comments as ran at the same rate for all observers in the universe or at least that can be scaled to such a common rate, actually his hypothetical time was supposed to base on the observers set the universal time as the frame of reference (standard time)—“absolute time” was the time for human beings to utilize the universal time as standard time but it was not the universal time, like the understanding of man-made name “year” and the existent “period” of the Earth’s moving round the Sun. Isaac Newton had not thought much that everyone might have his own time standards, i.e. observers might think that some times started at a certain moment, for an instance, measuring the time of a car traveling from position A to B, the observers might postulate that the time of the car staying at “point A” was the initial time or zero time.
Albert Einstein’s “relative time” was the time for us to depict that the observers might live in different time coordinates systems (e.g. in a flying plane). Both premises of the discussion about time were different, and neither of two giants told time clearly. Isaac Newton would better know that times could be changed or adjusted (e.g. Daylight Saving Time), and in the meantime, Albert Einstein would better know that a unified standard time was very important for humans(e.g. the Greenwich Mean Time). Both “absolute time” and “relative time” are subjective times because both would be constituted by human beings or both needed observers’ conduct or involvement. I divided the subjective time into three groups: absolutely subjective time, relatively subjective time and indefinite subjective time. Now let us discuss them one by one.
The absolutely subjective time: exactly numeric time.
General notion of time is considered as “duration” or “interval,” but sometimes time can be considered a “point,” for example, “June 20, 1980,” “three o’clock sharp,” “today,” “yesterday,” etc., in addition, “one minute,” “20 years,” “two hours,” “Monday,” “last year,” “tomorrow,” and so on, all above are absolutely subjective times. By the way, “yesterday” can be called a “point of time” or “24 hours in the past.”
The relatively subjective time: determined by means of observation, calculation and measurement.
For example, the units of time constituted by us—“second,” “minute,” “hour,” “day,” “year,” etc.
The contents of the relatively subjective time are wide abroad, which closely refers to the scientific researches and personal experiences. Giving an instance of “event of wink” below, it is hoped that you would comprehend it easily.
A person or an observer,
had measured the “time of wink” of his own (T1).
had measured the “time of wink” of others (T2).
had been measured the “time of wink” by others (T3).
had measured the “time of wink” of passengers in a traveling train (T4).
had been measured the “time of wink” by passengers in a traveling train (T5).
had computed the average of “time of wink” of humans (T6).
From T1 to T6, all of them are relatively subjective times. There are countless events and phenomena in the universe. We could find out the different time relationships by all means within the permissibility of science and technology if we wish.
The indefinitely subjective time: the ambiguous or uncertain time.
There are many kinds of indefinitely subjective time in our lives, which enriches our imagination and languages. For example, “time is money,” “time flies,” “time was elapsing quickly when I talked to my girlfriend this morning,” “past,” “present,” “future,” “ten years ago,” “about 20 minutes,” etc., all of them are indefinitely subjective times. Now giving other instances, “Past is dead time; Present is right now; Future is imaginary time,” “Yesterday is our history; Today is our living; Tomorrow is our hope,” “Real time is till now; Future is from now on,” etc.
3.什么是时间单位?(unit of time)
What is the unit of time?
Everyday we use “second,” “minute,” “hour” to tell the time. As known, they are parts of the units of time to let us easily to measure or scale the time in our life. The SI (international system) base unit of time is the “SI second.” The definition of “second” was based on several referential standards, here are introduced the “SI second.” Its definition is: “the second is the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom.” It is not hard to realize that there is no difference in essence between the “SI second” and the “calendar year,” which both (subjective time) are still “intervals” fixed by us to make use of the regularities of the objective times for our conveniences while calculating. Now more clearly the objective time is a kind of existences and is very important for our living.
Time usually is considered as an interval (e.g. 1980—1985) or a continuum (e.g. the universal time). In reality or with respect to time coordinates, for the conveniences, in statistics some intervals were regarded as “point of time,” e.g., as mentioned, “June 20, 1980,” “year 1990,” as well “second.” The continuity of time ultimately refers to what the smallest unit of time should be, and the question will be discussed further later on.
“SI second” is not the smallest unit of time. At the moment Plank-time is considered the smallest unit of time that theoretically could be measured -- it is about 5.4x10-44 seconds. We still could not find the smallest unit of time, though the smallest unit of time would be significant in the territory of science. I supposed that someday we would have defined the smallest unit of time as “something” similar to “photon,” but here I dared to present a new word “chronotum” which was combined with “chrono” (from Greek khronos--time) and “quantum.” The term “chronotum” represents the smallest the quantum of time or the smallest unit of time.
The objective time does not need the “unit of time”, nor does the concept of “unit.” But the subjective time is established by us, and it can be altered and defined the “units.” We could find out the regularities of the objective times and could quantify them with the subjective times, as well as make use of the regularities of the objective times to define as “units” or time standards, for the same instance mentioned, the Earth’s rotational period around the Sun—one of the objective times, which was defined as “year” or “365 days,” certainly the definition of “second” is also an example. We already knew time is a kind of existences; it can be regular; it can have unit or it does not need unit. We will discuss the “shapes of time” below.
Is time curved or straight?
许多人认为时间是直线的是因为我们习惯把时间与时间箭头(arrow of time)或时间作标联系在一起。时间轴线在时间坐标系统里，我们通常都是画成直线的，但是实际上时间轴线并不能表示时间的形状就是看起来那样的。时间箭头只能说明时间的方向性，它不能说明时间是直线的或一定指向未来。我们一般都认为时间箭头应该指向未来，这是一个错觉，时间箭头是根据我们的需要来标明时间方向的，如果根据统计需要，我们当然可以这样用时间箭头表示时间，参看“图表X” 和“图表Y。”当然，把时间箭头画成曲线也不能算错，参看“图表Z，”这个图反映的是“年”的变化范围(从365天到366天)。
Many people thought time is straight because of the relations to the arrow of time and time coordinates. Time-axis we usually drew is linear in time coordinate systems, but the time-axis could not express that the shape of time was looked like that. The arrow of time can only show us the direction of time, it shall not tell us time is straight or time must go towards the future. Usually the arrow of time was supposed to point to the future, but that was an illusion. On the basis of our needs, the arrow of time no more than indicates direction of time, and not other functions or meanings. According to needs of statistics, we certainly could use the arrow of time to mark the direction of time like these (see figure x and figure y below). Of course, it was not wrong that the arrow of time was drawn as curve (see figure z, “year” varies from 365 days to 366 days).
Times have shapes, similar to the magnetic field lines. We can not directly see the shapes of times, but we are able to perceive the shapes of times through the changes of objects. Below showing some charts, I will explain what kinds of shapes times have.
“图表 a” 和 “图表 b”是“某种运动与时间”关系的一种不同的坐标描述方法，也就是某种运动从位置A(Position A )到位置B(Position B)的时间变化图，即，时间随着某种运动的变化是如何变化的。“图表a” 表示某种非直线运动的时间变化图;“图表 b” 表示某种直线运动的时间变化图。从这两个图中，我们可以看出某种运动的时间运行(形状)可以是直线的，也可以是曲线的。
Figure a. and Figure b indicated that we could draw the coordinates of “motion and time” in a different way. The two charts depicted the changes of time with respect to a certain motion from position A to B--time changed following with the changes of a certain motion. “Figure a” showed us how the time changed when the motion moved along with non-straight line;“Figure b” described the time’s changes while the motion went a straight line. We were also told from pictures that the time’s running (shape) of certain motion could be curved or straight.
Now taking a real instance, a car (M) started from point A and arrived at point B. If M went along with a straight line, it was regarded the time of M’s travel from A to B was straight (figure b); If M traveled along with a curved line, it was regarded the time of M’s travel from A to B was curved or non-straight line (figure a). The interval of M’s traveling from A to B equaled to the cumulating times, which M spent by going through every point from A to B. Detailed in section 6 below.
看“图表c，”它描述的是“年”与时间(time)的关系。我们暂且把地球绕太阳公转看成是圆形的。这个周期(客观时间)就是这个圆上的时间“一点一点”组成的，我们可以说这个周期(客观时间)是圆形的。 现在我们把这个周期人为定义为“年，” ( year) 大家知道，“年”也是有变化的，“年”并不是绝对的365天，“年”的平均时间是365.2421天。通常“今年”(this year)与 “去年”(last year)是不相同，这就是我们公历(the Gregorian calendar or solar calendar)有闰年(leap year)的原因。再如，一般情况下，我们知道时钟和手表都有“秒针，”时钟和手表的秒针转一圈，它告诉我们时间过去了一分钟，而对于“秒针”来说它经历的时间也是个圆形的。
From Figure c, it depicts the relationship of “year” and “time.” Here, the orbit of the Earth’s moving around the Sun is tentatively considered round. This period (a kind of objective times) consists of every “point of time” on this circle, so we can call this period is round. Now we change to call this period as “year.” “Year” is not exactly equal to “365 days” or “366 days.” It equals to 365.2421 days on average. “This year” is normally different from “last year,” that is why our calendar(the Gregorian calendar or solar calendar)has leap year. For another example, the watch or clock has “second hand.” The second hand goes a circuit that tells us time passes a minute. For the “second hand”, time it went through could be called “round in shape.”
From Figure d, it shows the relationship of “year” and “time” in different way. “Year” varies from 365 days to 366 days. From this chart, we see the time (“year”) was also described as a curved line. How to describe the regularities of times depends on what you want to tell, for example, “year” is round” (Figure c), or “year” varies from 365 days to 366 days (Figure d) and “year” is curved in the time coordinate.
According to the paradigms and diagrams above, we can draw a conclusion that time can be straight, time can be curved and time can be rounded. In result, time has shape, but has not fixed shape.
It needs to mention that we must distinguish the concrete concept of time from the abstract concept of time. The concrete time can be measured—it is a part of our measurement systems; the abstract time is known as the definition of time and the essence of time, and the abstract time can not be measured.
We have already discussed the concrete concept of time (included the objective time, the subjective time and many other notions), which could be helpful to understand the abstract concept of time below.
What is the definition of time? What is the essence of time?
What is time? Answering what is time, namely we would find out the definition and the essence of time. How to define the time is a longstanding issue in science and in philosophy. Two science representatives—Isaac Newton and Albert Einstein, their theories intensively referred to time. Regrettably they did not seriously speculate what was the definition of time and what was the essence of time.
Nowadays our understandings of time, in any case, have been mastered by Relativity, and most people still remain realizing that time was merely relative. In my opinion, the “relative concept” of time was not considered prior to the “absolute concept” of time, and imprecisely they looked like a double-sides coin. In addition, we had to face the different explanations of time while looking up the dictionaries and encyclopedia. The viewpoints I listed below basically represented our previous comprehension of time.
Time: the indefinite continued progress of existence, events, etc., in past, present, and future regarded as a whole.
Time: a continuous measurable quantity from the past, through the present, and into the future.
The American Heritage Dictionary:
Time: a non-spatial linear continuum in which events occur in an apparently irreversible succession.
Interpretation from Wikipedia—web-based encyclopedia (Aug. 22, 2006)
Time generally refers to the concept of a universal process or medium which allows all physical changes in the present to become events in the past. …
Time has been a major subject of science, philosophy and art. Though dictionaries present some (varied) definitions of time, it is difficult to provide an uncontroversial definition because there are wildly divergent views about its meaning, and concerns about where there are any simpler terms with which to define it. … To avoid these definitional problems, many fields use an ‘operational definition’ in which only the units of measurement are defined.
From Encyclopedia Britannica
Time is a measured or measurable period, a continuum that lacks spatial dimensions. Time is of philosophical interest and is also the subject of mathematical and scientific investigation.
We could still find out some other definitions, which I could hardly say they were wrong, such as I said “time is time,” or most of them described a process of time occurrence. Some, including the viewpoints listed above, probably could help you understand the definition of time and the essence of time subsequently.
The definition of time: Time is the reflection or description of change.
Change means that a state occurs from same to different. Time is the reflection of change means there are occurrences of time as long as there are changes, i.e. if there is no change, there is no time. Therefore, we could get a conclusion that Change is the only subject of time, no others. However, if humans are the subject of time, the answer is no, because there are no humans, time still can exist.
Regardless of the argument about the subject and object in philosophy, here in the article referring to the subject and object, it means if there is no subject (main or main cause), there is no reason for object (subordinate) to exist, in another word, the object (e.g. time) must yield to the subject (e.g. change).
Time is also considered merely to describe the change. We know space could change, e.g., the space inside a balloon could be smaller or bigger, or space could be curved; matter could change, e.g., the motion and the volume of matter could change; our thoughts could change, e.g. yesterday he thought the Earth is flat, but today he thought the Earth is round; certainly time itself could change, to take an instance, we know time goes towards the future, the past is behind the present, the future is ahead of the present. All changes mentioned above can be described by using the concept of time, e.g., the change of space which curved by gravitation from state A to state B took three seconds; the period of the Moon’s rotation around the Earth is about 29.53 days(called “month” in lunar calendar) and so on. And time did not reflect or describe the space or matter other than their changes, i.e. time did not mean to describe certain bodies, but their changes. It needs to mention here that time, space and matter are different and independent existences
Also, change can be described by using other concepts, for example, length, mass, temperature, force, area, velocity, power, etc., they can also tell us the changes of certain existences or phenomena, and what existences or phenomena we want to describe by using the concepts above depends on what regularities or laws we want to tell. To describe the events in our lives, we can choose the concept of time, of course, as well as other concepts, e.g., “the car accident happened three days ago;” “the car accident happened because of the bad weather.”
Always, there are changes in the universe and universe itself. If there were not changes, the universe would end, and we would have no way to talk about time. The universe would rather be called substantial or in motion than the universe is always in change. Now take a look at the definition of motion in physics that motion means the change of position of one body with respect to another ( Encyclopedia).
To depict or define a certain concept (e.g., the Universe), we have to tell the whole compositions of this concept. The universe consists of not only the physical parts but also the non-matter parts (e.g. non-matter parts include space, time, consciousness, etc.), as a consequence, we could not call the universe is only substantial or physical.
In tradition, science developed around the “the concept of matter,” and similarly, in some ways, our world was built up by “matter,” and the researches of non-matter parts developed slowly. Though the arguments of consciousness lasted for thousands of years, we have not known what the essence of consciousness should be. It is congratulated that some people established the brain science or thinking science, as well as “ethics”. The hard thing is to use thinking to think thinking.
And Relativity has made us understand space and time more, but it was confusing that Albert Einstein bound up space and time into together. Moreover, the successors were not able to take “space-time” apart, i.e. actually they neglected time’s objectivity--time is a kind of existences and it is not an imaginary thing. In addition, according to Relativity, space-time could be curved together. We have already known that change is the subject of time，and I really want to know how the gravitation would curve the “change.” And also I was wondering why we could not define the unit of space or could not answer the essence of space, by contrast, time had its unit(s), and I will answer the essence of time later on. I would not like to talk space much here, what I concerned is that time is to describe the change of space, and not space itself. Time does not subject to space.
What is the essence of time?
几乎每个人家里都有时钟(clock)。时钟的“滴答声”让我们意识到时间的存在，它还告诉我们时间正在流逝。时间总是流向未来，就算宇宙膨胀到一定时候往回坍缩，宇宙时间还是向前走的，膨胀(Big Rip)和坍缩(Big Crunch)应看成是宇宙变化全过程中的一部分。时间是否可以回到过去?我觉得想像是一种财富，我的确很想重过大学生活。
Almost every family has the clock on the wall. The ticks from the clock tell us the existence of time, and also let us know time is elapsing. Time always flows towards the future, even if the universe should collapse back when the expansion stopped, the universal time would still proceed. The collapse (Big Crunch) and expansion (Big Rip) should be regarded as the parts of the whole evolution of the Cosmos. Could time go back to the past? I really think the imagination is a kind of treasures, and I really wish to go back to the university to study again.
时间是一种存在，它既是客观的，又是主观的。客观性就是不受思想所支配，或独立于意识之外的存在，例如，月亮绕地球的运行周期，它在人类出现之前就存在着。时间又是主观的，例如，我们日历的月份(month)可以定义为30天，也可以定义为31天，而2月份(Feb.)，我们有28天和29天。最好不要去修改客观时间，比如，把月亮“推”得运行快一些，但主观时间可以根据具体情况进行调整，夏时制(Daylight Saving Time)就是一个例子。
Time is a kind of existences, and it is objective as well as subjective. Talking about its objectivity—a thing external to the thinking mind (consciousness) or subject, for example, as known, the period of the Moon’s rotation around the Earth, it existed much earlier than humans did. Time could be subjective, for example, the “month”, a kind of subjective times, in our actual calendar is defined as some are 31 days, some are 30 days and February can be altered as 28 days or 29 days. It would be the better way not to change the objective time, e.g. “pushing” the Moon to move more quickly. But the subjective time can be adjusted by us, which Daylight Saving Time (DST) is a good example.
The essence of time is concluded below by far we know:
Time is a kind of existences; it is both objective and subjective.
Change is the only subject of time, no others; if there is no change, there is no occurrence of time.
Time consists of the unit (units) of time.
Time has not fixed shape; time goes (flows) towards the future.
6. 时间的表达式(the formulation of time)
The formulation of time
时间是客观世界的一种存在;时间也可以有规律性。我们以往习惯于通过时间坐标研究某种事情的变化(例如，运动);实事上，我们很少通过坐标来研究时间的变化。方便起见，我建议今后使用坐标系来研究时间时，用x-time 暗示“x”为纵坐标轴，“time”为横坐标轴;time-x 暗示为“time”为纵坐标轴(ordinate)，“x”为横坐标轴(abscissa)。
• 时间(t)等于每一事情(every thing)从原状态A发生到不同状态B的每一个时间单位的积分。
• t = f(x)
• t = ∫abf(x)dx
Time is a kind of existences in the universe, therefore time could have regularity. Before now, we usually studied the changes of the certain “things” by time coordinates, and in fact we seldom studied the changes of time by the coordinate systems. For the convenience, I would like to suggest, when we depict the coordinates referring to time in the future, that “x-time” would imply “x” as ordinate and “time” as abscissa; “time-x” would imply “time” as ordinate and “x” as abscissa.
To compute or measure a certain time (t), below indicate the formulation of time.
• Time (t), that occurred when every thing happened from same state (A) to different state (B), equals to the integrals of every unit of time.
• Time can not go backwards automatically.
The expression in mathematics：
• t = f(x)
• t = ∫abf(x)dx
x on the interval [a,b]
The chart of “Time System”
The concrete times refer to the objective time and the subjective time. The objective time might be discovered and utilized by us, and the subjective time is our applied time system. This chart might help us remember and comprehend the concept of time.
The theory of time has shown not only the classification and interpretation of time, but also importantly it reflected one of our efforts of the explorations for the Truth of the Cosmos. So-called the Truth of the Cosmos, I realized it should include some contents below:
Created or occurred naturally, namely the questions about the origin of the Cosmos and man.
Interpretations of existences and phenomena, namely the questions about the laws or rules of the Cosmos itself, existences and phenomena in the Cosmos.
Definition and essence of the Cosmos, namely the philosophical notion of the Cosmos.
Destiny of the Cosmos and human beings.
Seeking for the Truth of the Cosmos makes the life of humankind become significant.