Tag Archives: time

Close-up of a fingerprint being examined under a magnifying glass with a blue-toned background.

The Top Five Unsolved Mysteries of Science

There are numerous unsolved mysteries in science. In this post, I will delineate the top five that I consider the most profound.

  1. What caused the Big Bang? Cosmologist are in strong consensus that the Big Bang resulted in the evolution of the Universe, but there is no scientific consensus as to what caused the Big Bang. There are several theories, including one that I put forward in my book, Unraveling the Universe’s Mysteries. However, none of the current theories, including the one that I forward in my book, have garnered consensus in the scientific community. The origin of the Big Bang is arguably the greatest scientific mystery of all time, and it remains an area of considerable research.
  2. How did life start on Earth? There are two fundamental theories regarding the origin of life on Earth. The first theory, panspermia, holds that life exists throughout the Universe and is distributed by meteoroids, asteroids and planetoids. This theory is compelling, but it still leaves us with another profound question, “How did life originate in the Universe?” There are no widely accepted theories to address that question. The second theory, regarding how life started on Earth, is termed biopoesis. It holds that life forms from inorganic matter through natural processes. This theory is also compelling, but no experimental process has resulted in life forming from inorganic matter. By simple logic, one or even both of these theories is correct. Obviously, in the early Universe, life had to form from inorganic matter. It is also possible that life also started on Earth via the same process. It is also possible that once life formed in the Universe, it was spread by meteoroids, asteroids and planetoids.
  3. What is the nature of time? Some scientists, myself included, argue time is real. This stance suggests that time travel would also be possible. In my book, How to Time Travel, I devote considerable attention to the various philosophies of time and to experiments that suggest time is real. I also delineate experiments that prove time travel to the future is real, as well as experiments that prove reverse causality is real (i.e., literally, the effect precedes the cause). I also delineate experiments that prove that something in the future can alter the past. Some philosophers and scientists argue that time is a mental construct. It is not real. That humans invented time to measure change. If that is true, time travel would not be possible, except in your mind. However, scientific experiments, such as time dilation and reverse causality suggest otherwise. What do you think?
  4. What is the fundamental theory of physics? Modern physics rests on two pillars, The first pillar is Einstein’s theories of relativity. The second pillar is quantum mechanics. Although Einstein’s theories explain phenomena on the macro-scale (i.e., the typical scale we observe in our every day life), it fails to explain phenomena on the quantum level (i.e., the level of atoms and subatomic particles). To explain phenomena on the quantum level we must turn to quantum mechanics. This would be acceptable, except Einstein’s theories of relativity are incompatible with quantum mechanics. They do not come together to adequately explain gravity. Physicists have long sought the “theory of everything.” Some physicists, like world renown cosmologist Stephen Hawking, suggest that M-theory (i.e., the most comprehensive string theory) fits the bill. However, there is no consensus or proof that M-theory is even valid. Until the next Einstein comes along and solves the problem, we don’t have a fundamental theory (i.e., a single unifying theory) of physics.
  5. Does life exist on other planets or is the Earth unique? Almost every scientist agrees that given the vastness of the Universe and the numerous Earth-like planets that have been discovered, there must be life somewhere else in the Universe. Indeed, many believe, myself included, that advanced aliens, similar or more advanced than ourselves, must also exist. However, there has been no definitive publication that proves life exists elsewhere in the Universe. I will refrain from getting into UFOs, government conspiracies and similar material. I don’t refute such theories, but as a scientist I must base my conclusions on definitive evidence. To date, we have no definitive evidence (i.e., widely accepted by the scientific community) regarding life on other planets. However, mathematically, I think life on other planets is a certainty. What do you think?
Close-up of an ornate astronomical clock with zodiac signs and intricate golden details.

Five Facts about Time

Here are some interesting facts to ponder about of time:

  1. There is no widely accepted scientific definition of time as a stand alone entity. The reason for this is that according the Einstein’s theory of relativity, time and space are integrated into space-time.
  2. Some physicists argue that “time” has not always existed. According to the big bang theory, the universe started as an infinitely dense small energy ball that expanded to create the universe we now observe. Since some physicist argue that time is a measure of change, before the big bang, there was no change. Hence, there was no time.
  3. Time as measured by clocks will actually slow down in a reference frame moving close to the speed of light or in a high gravitational field. This has been experimentally proven.
  4. Time on Earth is slowing down. Our human perception of time comes from the rotation of the Earth relative to the Sun. Due to tidal friction from the sun and moon, the solar day is lengthening by 1.7 milliseconds each century as the Earth’s rotation slows down.
  5. Your significant other has their own definition of time. It is called a “jiffy.” The jiffy is an undefined time interval that can mean a faction of second to an hour or more. They generally use it in the phrase, “I’ll be ready in a jiffy.”  🙂
A black and white image of a clock face with a spiral effect distorting the numbers and hands.

Twisting the Arrow of Time

The flow of time, sometimes referred to as the “arrow of time,” is a source of debate, especially among physicists. Most physicists argue that time can only move in one direction based on “causality” (i.e., the relationship between cause and effect). The causality argument goes something like this: every event in the future is the result of some cause, another event, in the past. This appears to make perfect sense, and it squares with our everyday experience. However, experiments within the last several years appear to argue reverse causality is possible. Reverse causality means the future can and does influence the past. For example, in reverse causality, the outcome of an experiment is determined by something that occurs after the experiment is done. The future is somehow able to reach into the past and affect it. Are you skeptical? Skepticism is healthy, especially in science. Let us discuss this reverse causality experiment.

In 2009, physicist John Howell of the University of Rochester and his colleagues devised an experiment that involved passing a laser beam through a prism. The experiment also involved a mirror that moved in extremely small increments via its attachment to a motor. When the laser beam was turned on, part of the beam passed through the prism, and part of the beam bounced off the mirror. After the beam was reflected by the mirror, the Howell team used “weak measurements” (i.e., measurement where the measured system is weakly affected by the measurement device) to measure the angle of deflection. With these measurements, the team was able to determine how much the mirror had moved. This part of the experiment is normal, and in no way suggests reverse causality. However, the Howell team took it to the next level, and this changed history, literally. Here is what they did. They set up two gates to make the reflected mirror measurements. After passing the beam through the first gate, the experimenters always made a measurement. After passing it through the second gate, the experimenters measured the beam only a portion of the time. If they chose not to make the measurement at the second gate, the amplitude of the deflected angle initially measured at the first gate was extremely small. If they chose to make the measurement at the second gate, the deflected angle initially measured at the first gate was amplified by a factor of 100. Somehow, the future measurement influenced the amplitude of the initial measurement. Your first instinct may be to consider this an experimental fluke, but it is not. Physicists Onur Hosten and Paul Kwiat, University of Illinois at Urbana-Champaign, using a beam of polarized light, repeated the experiment. Their results indicated an even larger amplification factor, in the order of 10,000.

The above experimental results raise questions about the “arrow of time.” It appears that under certain circumstances, the arrow of time can point in either direction, and time can flow in either direction, forward or backward. This is a scientific result, and I am not going to speculate about religious connotations, free will, and the like. Obviously, there are numerous religious connotations possible and a plethora of associated questions.

Source: How to Time Travel (2013), Louis A. Del Monte

science of time & time dilation

The Philosophy of Time and Time Travel – Part 2/2 (Conclusion)

This is taken from Appendix 4 of my new book, How to Time Travel, to be published by early September 2013.

Let us examine the three major philosophical schools on the nature of time and their implications regarding time travel.

1. Presentism theory of time

The presentism theory of time holds that only the present is real. The past is over. Therefore, it is no longer real. The future has yet to occur. Therefore, the future is not real. Presentists argue that our mind remembers a past and anticipates a future, but neither is real. They are mental constructs.

Arguably, the most famous presentist is Augustine of Hippo (a.k.a. St. Augustine), who compared time to a knife edge. The present represents a knife edge cutting between the past and future. Ironically, this means Augustine of Hippo is not real, since he lived and died in the past. Therefore, should we study Augustine of Hippo, who, by his own philosophy, is not real? Of course, I am only being contentious to make a point.

Presentism has a large following, especially among Buddhists. Fyodor Shcherbatskoy (1866–1942), often referred to as the foremost Western authority on Buddhist philosophy, summed up the Buddhist view of presentism with these few words: “Everything past is unreal, everything future is unreal, everything imagined, absent, mental…is unreal…Ultimately real is only the present moment of physical efficiency.” Uncountable millions of Buddhists still ascribe to this view of time and reality.

A cogent philosophical argument can be made for presentism, but presentism is problematic from a scientific viewpoint. When we discussed the special theory of relativity, we learned that the present is a function of the position and speed of the observer. Therefore, what is the present to one observer may be the past to another.

From the standpoint of time travel, presentism renders the question “how to time travel” moot. If we embrace presentism, there is no past or future, and time travel is meaningless. Fortunately, though, other philosophies of time open the door to time travel. Let us examine the next one.

2. Growing universe theory of time

This theory of time is also referred to as “growing block universe” and “the growing block view.” However, regardless of the name, they all hold the same philosophy of time. The past is real, and the present is real. The future is not real. The logic goes something like this: The past is real because it actually happened. We experience it, and we document it. We call it history. The present is real because we experience it. We often share the present with others. The future is not real because it has not occurred.

Why do all the names for this theory of time start with the word “growing”? The concept is that the passage of time continually expands the history of the universe. Actually, this is logical. The history of the world, and the universe, continues to expand with the passage of time. The history section of any library is destined to grow with time.

In this philosophy of time, only time travel to the past makes sense, since for growing-universe philosophers, the past is real. We cannot time travel to the future, since the future has yet to occur. Therefore, it is not real.

As logical as this theory of time may appear, there is scientific evidence that the future is real and can influence the present. We discussed this evidence in the section titled “Twisting the arrow of time” in chapter 1. Now, let us examine the last significant philosophy of time.

3. Eternalism theory of time

The eternalism theory of time holds that the past, present, and future are real. The philosophy of this theory rests on Einstein’s special theory of relativity. Essentially, the special theory of relativity holds that the past, present, and future are functions of the speed and position of an observer.

While Einstein never equated time with the fourth dimension, Minkowski’s geometric interpretation of Einstein’s special theory of relativity gave birth to four-dimensional space, with time as part of the fourth dimension. In Minkowski’s interpretation, often termed “Minkowski space” or “Minkowski spacetime,” the fourth dimension includes time and is on equal footing with the normal three-dimensional space we currently encounter. However, Minkowski’s fourth dimension borders on the strange. In Minkowski spacetime, the fourth dimension, X4, is equal to ict, where i = √-1, an imaginary number, c is the speed of light in a vacuum, and t is time as measured by clocks. The mathematical expression ict is dimensionally correct, meaning that it is a spatial coordinate, not a temporal coordinate, but is essentially impossible to visualize, since it includes an imaginary number. What is an imaginary number? It is a number that when squared (multiplied by itself) gives a negative number. This is not possible to do with real numbers. If you multiply any real number, even a negative real number like minus one, by itself, you always get a positive number. Therefore, it is impossible to solve for the square root of minus one.

Although we can express it mathematically as √-1, it has no solution, and it is termed an imaginary number. Does that mean Minkowski was wrong about the fourth dimension? Actually, it does not. It does say that it is a mathematical construct, and intuitively, for most of us, impossible to visualize. However, the special theory of relativity continues to be taught using Minkowski spacetime, which the bulk of the scientific community considers a valid geometric interpretation. In either its algebraic form, as first presented by Einstein, or its geometric form, as interpreted by Minkowski, the majority of the scientific community considers the special theory of relativity the single most successful theory in science. It has withstood over a century of experimental investigation, and it is widely considered verified.

Because of its scientific underpinnings, the eternalism theory of time is widely accepted in the scientific community. If we adopt the eternalism theory of time, then time travel to the past or future becomes equally valid. In addition, no scientific theory contradicts or prohibits time travel. Said more positively, based on Einstein’s theories of relativity, which lay a theoretical foundation for time dilation (i.e., time travel to the future) and closed timelike curves (i.e., time travel to the past), most of the scientific community would support the scientific possibility of time travel.

Multiple overlapping clock faces with various times, creating a surreal and abstract time concept in blue tones.

The Time Uncertainty Interval

The Time Uncertainty Interval: This is from appendix 5 (The Science of Time) of my new book, How to Time Travel, due to be published on Amazon early September 2013.

Since the smallest unit of time is only definable as the Planck interval, this suggests there is a fundamental limit to our ability to measure an event in absolute terms. This fundamental limit to measure an event in absolute terms is independent of the measurement technology. The error in measuring the start or end of any event will always be at least one Planck interval. This is analogous to the Heisenberg uncertainty principle, which states it is impossible to know the position and momentum of a particle, such as an electron, simultaneously. Based on fundamental theoretical considerations, the scientific community widely agrees that the Planck interval is the smallest measure of time possible. Therefore, any event that occurs cannot be measured to occur less than one Planck interval. This means the amount of uncertainty regarding the start or completion of an event is only knowable to one Planck interval. In our everyday life, our movements consist of a sequence of Planck intervals. We do not perceive this because the intervals are so small that the movement appears continuous, much like a watching a movie where the projector is projecting each frame at the rate of approximately sixteen frames per second. Although each frame is actually a still picture of one element of a moving scene, the projection of each frame at the rate of sixteen frames per second gives the appearance of continuous motion. I term this inability to measure an event in absolute terms “the time uncertainty interval.”