Category Archives: Time Travel

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The Top Five Unsolved Mysteries of Science

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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?
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Reverse Causality – The Future Can Change the Past

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Most people find reverse causality intriguing, but impossible. Yet, it has a strong basis in science. In my book, How to Time Travel, I discuss a number of reverse causality examples. Here are some from the book.

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 Double-Slit Experiment

There are numerous versions of the double-slit experiment. In its classic version, a coherent light source, for example a laser, illuminates a thin plate containing two open parallel slits. The light passing through the slits causes a series of light and dark bands on a screen behind the thin plate. The brightest bands are at the center, and the bands become dimmer the farther they are from the center.

The series of light and dark bands on the screen would not occur if light were only a particle. If light consisted of only particles, we would expect to see only two slits of light on the screen, and the two slits of light would replicate the slits in the thin plate. Instead, we see a series of light and dark patterns, with the brightest band of light in the center, and tapering to the dimmest bands of light at either side of the center. This is an interference pattern and suggests that light exhibits the properties of a wave, which is well accepted in the scientific community. This is termed the dual nature of light. This portion of the double-slit experiment simply exhibits the wave nature of light.

The above double-slit experiment demonstrates only one element of the paradoxical nature of light, the wave properties. The next part of the double-slit experiment continues to puzzle scientists. There are five aspects to the next part.

1. Both individual photons of light and individual atoms have been projected at the slits one at a time. This means that one photon or one atom is projected, like a bullet from a gun, toward the slits. Surely, our judgment would suggest that we would only get two slits of light or atoms at the screen behind the slits. However, we still get an interference pattern, a series of light and dark lines, similar to the interference pattern described above. Two inferences are possible:

a. The individual photon light acted as a wave and went through both slits, interfering with itself to cause an interference pattern.
b. Atoms also exhibit a wave-particle duality, similar to light, and act similarly to the behavior of an individual photon light described (in part a) above.

2. Scientists have placed detectors in close proximity to the screen to observe what is happening, and they find something even stranger occurs. The interference pattern disappears, and only two slits of light or atoms appear on the screen. What causes this? Quantum physicists argue that as soon as we attempt to observe the wavefunction of the photon or atom, it collapses. Please note, in quantum mechanics, the wavefunction describes the propagation of the wave associated with any particle or group of particles. When the wavefunction collapses, the photon acts only as a particle.

3. If the detector (in number 2 immediately above) stays in place but is turned off (i.e., no observation or recording of data occurs), the interference pattern returns and is observed on the screen. We have no way of explaining how the photons or atoms know the detector is off, but somehow they know. This is part of the puzzling aspect of the double-slit experiment. This also appears to support the arguments of quantum physicists, namely, that observing the wavefunction will cause it to collapse.

4. The quantum eraser experiment—Quantum physicists argue the double-slit experiment demonstrates another unusual property of quantum mechanics, namely, an effect termed the quantum eraser experiment. Essentially, it has two parts:

a. Detectors record the path of a photon regarding which slit it goes through. As described above, the act of measuring “which path” destroys the interference pattern.
b. If the “which path” information is erased, the interference pattern returns. It does not matter in which order the “which path” information is erased. It can be erased before or after the detection of the photons.

This appears to support the wavefunction collapse theory, namely, observing the photon causes its wavefunction to collapse and assume a single value.

5. If the detector replaces the screen and only views the atoms or photons after they have passed through the slits, once again, the interference pattern vanishes and we get only two slits of light or atoms. How can we explain this? In 1978, American theoretical physicist John Wheeler (1911–2008) proposed that observing the photon or atom after it passes through the slit would ultimately determine if the photon or atom acts like a wave or particle. If you attempt to observe the photon or atom, or in any way collect data regarding either one’s behavior, the interference pattern vanishes, and you only get two slits of photons or atoms. In 1984, Carroll Alley, Oleg Jakubowicz, and William Wickes proved this experimentally at the University of Maryland. This is the “delayed-choice experiment.” Somehow, in measuring the future state of the photon, the results were able to influence their behavior at the slits. In effect, we are twisting the arrow of time, causing the future to influence the past. Numerous additional experiments confirm this result.

Let us pause here and be perfectly clear. Measuring the future state of the photon after it has gone through the slits causes the interference pattern to vanish. Somehow, a measurement in the future is able to reach back into the past and cause the photons to behave differently. In this case, the measurement of the photon causes its wave nature to vanish (i.e., collapse) even after it has gone through the slit. The photon now acts like a particle, not a wave. This paradox is clear evidence that a future action can reach back and change the past.

Summary

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. It may be hard to believe, but the above experiments have been repeated. In the case of the double-slit experiment, it has been repeated numerous times. No one has been able to provide a widely accepted explanation. Reverse causality is a true mystery of science.

 

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Is Time Travel Possible?

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Few topics in science capture the imagination like time travel. Science fiction, like H. G. Wells’ classic novel, The Time Machine, published in 1895, and science fact, like time dilation, continues to fuel interest in time travel. Let us start with the most important question: Is time travel possible?

Of course, time travel is possible. We are already doing it. At this point, I know my answer may come across a bit flippant. However, my answer has a kernel of truth. We are traveling in time. We continually travel from the present to the future. This is what philosophers refer to as the arrow of time. In our everyday experience, it moves in one direction, from the present to the future. I think, though, on a more serious note, what people want to know is can we travel back in time—or to a future date in time.

In theory, it is possible. Indeed, numerous solutions to Einstein’s special and general relativity equations predict time travel is possible. In general, no law of physics prohibits time travel. We will begin by considering two methods science proposes to travel in time .

Method 1: Time Travel to the Future – Faster-than-light (FTL)

Using faster than light or near the speed of light, time travel appears to offer methodologies grounded in science fact. Consider two examples:

1) Assume you build a spaceship capable of traveling near the speed of light. With such a spaceship, you literally can travel into the future. This may sound like science fiction, but it is widely accepted as scientific fact. Particle accelerators confirm it. We discussed it when we discussed time dilation and the twin paradox. All you need is the spaceship, and an enormous amount of energy to accelerate it near the speed of light. However, this is an enormous problem. From Einstein’s special theory of relativity, we know that as we begin to accelerate a mass close to the speed of light, it becomes more massive, and approaches infinity. Thus, to accelerate it close to the speed of light, we need an energy source that approaches infinity. Perhaps we would have to learn how to harness the energy of a star, or routinely create matter-antimatter annihilations to create energy. Today’s science is nowhere near that level of sophistication.

2) Assume you can move information (like a signal) faster than light. Theoretically, if we could send a signal from point A to point B faster than the speed of light, it would represent a form of time travel. However, a significant paradox occurs. Here is an example.
An observer A in an inertial frame A sends a signal to an observer B in an inertial frame B. When B receives the signal, B replies and sends a signal back to A faster than the speed of light. Observer A receives the reply before sending the first signal.

In 1907, Albert Einstein described this paradox in a thought experiment to demonstrate that faster-than-light communications can violate causality (the effect occurs before the cause). Albert Einstein and Arnold Sommerfeld in 1910 described a thought experiment using a faster-than-light telegraph to send a signal back in time. In 1910, no faster-than-light signal communication device existed. It still does not exist, but the possibility of its development is increasing. From quantum physics, it appears that certain quantum effects “transmit” instantaneously and, therefore, appear to transmit faster than the speed of light in empty space. One example of this is the quantum states of two “entangled” particles (particles that have physically interacted, and later separated). In quantum physics, the quantum state is the set of mathematical variables that fully describes the physical aspects of a particle at the atomic level. When two particles interact with each other, they appear to form an invisible bond between them. When this happens, they become “entangled.” If we take one of the particles, and separate it from the other, they remain entangled (invisibly connected). If we change the atomic state of one of the entangled particles, the other particle instantaneously changes its state to maintain quantum-state harmony with the other entangled particle. Significant experimental evidence indicates that separated entangled particles can instantaneously transmit information to each other over distances that suggest the information exchange exceeds the speed of light. Initially, scientists criticized the theory of particle entanglement. After its experimental verification, science recognizes entanglement as a valid, fundamental feature of quantum mechanics. Today the focus of the research has changed to utilize its properties as a resource for communication and computation.

Method 2: Time Travel to the Past – Using Wormholes

Scientists have proposed using “wormholes” as a time machine. A wormhole is a theoretical entity in which space-time curvature connects two distant locations (or times). Although we do not have any concrete evidence that wormholes exist, we can infer their existence from Einstein’s general theory of relativity. However, we need more than a wormhole. We need a traversable wormhole. A traversable wormhole is exactly what the name implies. We can move through or send information through it.

If you would like to visualize what a wormhole does, imagine having a piece of paper whose two-dimensional surface represents four-dimensional space-time. Imagine folding the paper so that two points on the surface are connected. I understand that this is a highly simplified representation. In reality, we cannot visualize an actual wormhole. It might even exist in more than four dimensions.

How do we create a traversable wormhole? No one knows, but most scientists believe it would require enormous negative energy. A number of scientists believe the creation of negative energy is possible, based on the study of virtual particles and the Casimir effect.

Assuming we learn how to create a traversable wormhole, how would we use it to travel in time? The traversable wormhole theoretically connects two points in space-time, which implies we could use it to travel in time, as well as space. However, according to the theory of general relativity, it would not be possible to go back in time prior to the creation of the traversable wormhole. This is how physicists like Stephen Hawking explain why we do not see visitors from the future. The reason: the traversable wormhole does not exist yet.

Hard as it may be to believe, most of the scientific community acknowledges that time travel is theoretically possible. If fact, time dilation of subatomic particles provides experimental evidence that time travel to the future is possible, at least for subatomic particle accelerated close to the speed of light. Real science is sometimes stranger than fiction. What do you believe?

 

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Is Time Travel to the Future Possible?

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Since the future doesn’t exist, how would it be possible to travel into the future? This question has been debated by both philosophers and scientists. However, time travel to the future is the only experimental evidence we have of time travel. To understand this, we will need to understand Einstein’s theories of special and general relativity.

The science of time travel was launch in 1905,  when Einstein published his special theory of relativity in the prestigious Annalen der Physik (i.e., Annals of Physics), one of the oldest scientific journals (established in 1790). The paper that Einstein submitted regarding his special theory of relativity was titled “On the Electrodynamics of Moving Bodies.” By scientific standards, it was unconventional. It contained little in the way of mathematical formulations or scientific references. Instead, it was written in a conversational style using thought experiments. If you examine the historical context, Einstein had few colleagues in the scientific establishment to bounce ideas off. In fact, Einstein essentially cofounded, along with mathematician Conrad Habicht and close friend Maurice Solovine, a small discussion group, the Olympia Academy, which met on a routine basis at Solovine’s flat to discuss science and philosophy. It is also interesting to note that Einstein’s position as a patent examiner related to questions about transmission of electric signals and electrical-mechanical synchronization of time. Most historians credit Einstein’s early work as a patent examiner with laying the foundation for his thought experiments on the nature of light and the integration of space and time (i.e., spacetime).

Einstein’s special theory of relativity gave us numerous new important insights into reality, among them the famous mass equivalence formula (E = mc2) and the concept and formula for time dilation. Time dilation lays the foundation for forward time travel, so let’s understand it in more depth.

According to special relativity’s time dilation, as a clock moves close to the speed of light, time slows down relative to a clock at rest. The implication is that if you were able to travel in a spaceship that was capable of approaching the speed of light, a one-year round trip journey as measured by you on a clock within the spaceship would be equivalent to approximately ten or more years of Earth time, depending on your exact velocity. In effect, when you return to Earth, you will have traveled to Earth’s future. This is not science fiction. As I mentioned above, time dilation has been experimentally verified using particle accelerators. It is widely considered a science fact.

What scientific experimental evidence do we have that time dilation is real. Here are several experiments that validate time dilation caused when particles move close to the speed of light.

Velocity time dilation experimental evidence:

Rossi and Hall (1941) compared the population of cosmic-ray-produced muons at the top of a six-thousand-foot-high mountain to muons observed at sea level. A muon is a subatomic particle with a negative charge and about two hundred times more massive than an electron. Muons occur naturally when cosmic rays (energetic-charged subatomic particles, like protons, originating in outer space) interact with the atmosphere. Muons, at rest, disintegrate in about 2 x 10-6 seconds. The mountain chosen by Rossi and Hall was high. The muons should have mostly disintegrated before they reached the ground. Therefore, extremely few muons should have been detected at ground level, versus the top of the mountain. However, their experimental results indicated the muon sample at the base experienced only a moderate reduction. The muons were decaying approximately ten times slower than if they were at rest. They made use of Einstein’s time dilation effect to explain this discrepancy. They attributed the muon’s high speed, with its associated high kinetic energy, to be dilating time.

In 1963, Frisch and Smith once again confirmed the Rossi and Hall experiment, proving beyond doubt that extremely high kinetic energy prolongs a particle’s life.

With the advent of particle accelerators that are capable of moving particles at near light speed, the confirmation of time dilation has become routine. A particle accelerator is a scientific apparatus for accelerating subatomic particles to high velocities by using electric or electromagnetic fields. In 1977, J. Bailey and CERN (European Organization for Nuclear Research) colleagues accelerated muons to within 0.9994% of the speed of light and found their lifetime had been extended by 29.3 times their corresponding rest mass lifetime. (Reference: Bailey, J., et al., Nature 268, 301 [1977] on muon lifetimes and time dilation.) This experiment confirmed the “twin paradox,” whereby a twin makes a journey into space in a near-speed-of-light spaceship and returns home to find he has aged less than his identical twin who stayed on Earth. This means that clocks sent away at near the speed of light and returned near the speed of light to their initial position demonstrate retardation (record less time) with respect to a resting clock.

Time dilation can also occur as a result of gravity. Our understanding of this comes from Einstein’s theory of general relativity. What is the difference between the special and general theory of relativity? Einstein used the term “special” when describing his special theory of relativity because it only applied to inertial frames of reference, which are frames of reference moving at a constant velocity or at rest. It also did not incorporate the effects of gravity. Shortly after the publication of special relativity, Einstein began work to consider how he could integrate gravity and noninertial frames into the theory of relativity. The problem turned out to be monumental, even for Einstein. Starting in 1907, his initial thought experiment considered an observer in free fall. On the surface, this does not sound like it would be a difficult problem for Einstein, given his previous accomplishments. However, it required eight years of work, incorporating numerous false starts, before Einstein was ready to reveal his general theory of relativity.

In November 1915, Einstein presented his general theory of relativity to the Prussian Academy of Science in Berlin. The equations Einstein presented, now known as Einstein’s field equations, describe how matter influences the geometry of space and time. In effect, Einstein’s field equations predicted that matter or energy would cause spacetime to curve. This means that matter or energy has the ability to affect, even distort, space and time. One important aspect prediction of general relativity was that gravitational fields could cause time dilation. Here are some important experiments that prove this aspect of general relativity is correct.

Gravitational time dilation experimental evidence:

In 1959, Pound and Rebka measured a slight redshift in the frequency of light emitted close to the Earth’s surface (where Earth’s gravitational field is higher), versus the frequency of light emitted at a distance farther from the Earth’s surface. The results they measured were within 10% of those predicted by the gravitational time dilation of general relativity.

In 1964, Pound and Snider performed a similar experiment, and their measurements were within 1% predicted by general relativity.

In 1980, the team of Vessot, Levine, Mattison, Blomberg, Hoffman, Nystrom, Farrel, Decher, Eby, Baugher, Watts, Teuber, and Wills published “Test of Relativistic Gravitation with a Space-Borne Hydrogen Maser,” and increased the accuracy of measurement to about 0.01%. In 2010, Chou, Hume, Rosenband, and Wineland published “Optical Clocks and Relativity.” This experiment confirmed gravitational time dilation at a height difference of one meter using optical atomic clocks, which are considered the most accurate types of clocks.

The above discussion provides some insight into time dilation, or what some term time travel to the future. However, is it conclusive? Not to my mind! Although we have numerous experiments that demonstrate time dilation (i.e., forward time travel) involving subatomic particles is real, we have been unable to demonstrate significant human time dilation. By the word “significant,” I mean that it would be noticeable to the humans and other observers involved. To date, some humans, such as astronauts and cosmonauts, have experienced forward time travel (i.e., time dilation) in the order of approximately 1/50th of a second, which is not noticeable to our human senses. If it were in the order of seconds or minutes, then it would be noticeable. Scientifically speaking, there is no documented significant evidence of human time travel to the future.

To answer the subject question of this post, time travel to the future appears to have a valid scientific and experimental foundation. However, to date the experimental evidence does not include significant (noticeable)  human time travel to the future, which leaves the question still unanswered. My own view is that when we develop space craft capable of speeds approaching the speed of light with humans on board, time dilation (time travel to the future) will be conclusively proven.

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Is Time Travel to the Past Possible?

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For time travel to the past to be possible would require that the past have a physical reality, namely that it continue to exist. If it did not continue to exist, it would suggest time travel to the past is impossible.

Time travel to the past has it theoretical foundation in Einstein’s special relativity. in the way of background, in November 1915, Einstein presented his general theory of relativity to the Prussian Academy of Science in Berlin. The equations Einstein presented, now known as Einstein’s field equations, describe how matter influences the geometry of space and time. In effect, Einstein’s field equations predicted that matter or energy would cause spacetime to curve. This means that matter or energy has the ability to affect, even distort, space and time.

Many of the predictions of general relativity have been scientifically verified. Two of the most important predictions for our study of time travel are (1) gravitational time dilation and (2) closed timelike curves.

Gravitational time dilation predicts that a clock in a strong gravitational field will run slower than a clock in a weak gravitational field. Therefore, a clock on the surface of Jupiter, a massive gas planet three hundred times larger than the Earth, resulting in a significantly stronger gravitational field, will run much slower than a clock on the surface of the Earth. This phenomenon was first verified on Earth, with clocks at different altitudes from the Earth’s surface. Using atomic clocks, time dilation effects are detectable when the clocks differ in altitude by as little as one meter.

Gravitational time dilation also occurs in accelerating frames of reference (i.e., noninertial frames of reference). According to Einstein’s general theory of relativity, an accelerated frame of reference produces an “inertial force,” also termed a “pseudo force,” that results in the same effect as a gravitational force in an inertial frame of reference. The equivalence of the inertial force in a noninertial frame of reference (i.e., an accelerating frame of reference) to a gravitational force in an inertial frame of reference (i.e., a frame of reference moving at a constant velocity) is termed the equivalence principle. The equivalence principle refers to the equivalence of “inertial mass” and “gravitational mass.” Therefore, a blindfolded person in a rapidly ascending elevator would experience a force equivalent to an increase in gravity, as if standing on a planet more massive than Earth. The blindfolded person would not be able to determine if the force experienced is inertial or gravitational. This effect also holds true for time dilation. Time moves slower in a highly accelerated frame of reference in much the same way it would as if it were in a strong gravitational field. It is important to note, a frame of reference can accelerate in two fundamental ways. It can accelerate along a straight line, or it can accelerate by rotating.

Next, let us discuss closed timelike curves. What is a closed timelike curve? It is an exact solution to Einstein’s general relativity equations demonstrating a particle’s world line (i.e., the path the particle follows in four-dimensional spacetime) is “closed” (i.e., the particle returns to its starting point). Closed timelike curves theoretically suggest the possibility of backward time travel. The particle’s world line is describable by four coordinates at each point along the world line, and when it closes on itself, the four coordinates at the start equal the four coordinates at the end. The particle, conceptually, went back to its past (i.e., the starting point). You can think of this like a horse racetrack. As the horse runs around the track, the horse eventually crosses the finish line, the starting point. If we allow the horse racetrack to represent a world line, then when the horse crosses the finish line, the horse has returned to its past (i.e., the starting point). In the mathematics of general relativity, the starting four coordinates, including the fourth dimensional coordinate that includes a time component, equal the four coordinates at the finish line.

The first person to discover a solution to Einstein’s general relativity equations suggesting closed timelike curves (CTCs) was Austrian American logician, mathematician, and philosopher Kurt Gödel, in 1949. The solution was termed the Gödel metric. Since 1949, numerous other solutions containing CTCs have been found, such as the Tipler cylinder and traversable wormholes, both of which will be discussed in section 3. The numerous solutions to Einstein’s general relativity equations suggest that time travel to the past is theoretically possible. However, the entire scientific community is not in complete agreement on this last point.

The largest issue that physicists have with backward time travel is causality violations (cause and effect), where the effect precedes the cause. These violations of causality are termed “time travel paradoxes.” Some physicists suggest that time travel paradoxes inhibit backward time travel, while other physicists argue that time travel paradoxes can be reconciled, and backward time travel is possible. There is no scientific consensus regarding the reality or practicality of time travel to the past. Although, there are a number of experiments that suggest reverse causality is scientifically possible.

Let us consider a recent experiment that demonstrates reverse causality is not only possible, but a scientific fact. 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 experiment strongly suggest that the future can influence the past. This implies, the past must continue exist and have a physical reality. If it no longer existed, how could the future influence the past. as the above experiments demonstrate.

This is an exciting time for science. Physical experiments suggest that the past may continue to physically exist. If that is true, then time travel to the past may be possible. The is an old saying in physics, “That which is not forbidden by physical law is compulsory.” The exact origin of the saying is not clearly known, but is often attributed to Murray Gell-Mann (born 15 September 1929), an American physicist who received the 1969 Nobel Prize in Physics for his work on the theory of elementary particles. To my mind, this saying suggests it is only a matter of time before we discover how to time travel to the past.

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Is There Any Scientific Evidence UFO’s Are Real?

Categories, Physics, Time Travel, Universe Mysteries, , ,

Internet searches for the keyword acronym “UFO” (unidentified flying object) are among the most popular on the Internet. According to Google, there are five million global searches per month for the keyword acronym “UFO”(without the quotes).

Let us start with a little background. Surprisingly, the United States Air Force (USAF) officially created the acronym “UFO” in 1953. Their intent was to replace the more popular phrases such as “flying saucers” and “flying discs” because of the variety of shapes reported. In their official statement, the United States Air Force defined the term UFO as “any airborne object which, by performance, aerodynamic characteristics, or unusual features, does not conform to any presently known aircraft or missile type, or which cannot be positively identified as a familiar object.”

The phenomena, namely UFO sightings, are worldwide. Various governments and civilian committees have studied them. The conclusions reached by the various organizations that have studied them vary significantly. Some conclude UFOs do not represent a threat and are of no scientific value (see, e.g., 1953 CIA Robertson Panel, USAF Project Blue Book, Condon Committee). Others conclude the exact opposite (see, e.g., 1999 French COMETA study, 1948 USAF Estimate of the Situation, Sturrock Panel).

Given the sheer volume of unexplained sightings by credible witnesses, including military, police, and civilian witnesses, there is little doubt that the UFO phenomenon is real and worldwide, and for the most part, there is no widely accepted public or scientific explanation of what they are or what their intentions might be.

Three popular speculations regarding UFOs are:

  1. They are future generations of humans who have mastered the science of time travel, and they are coming back either to observe us or to carry out other intentions.
  2. They are technologically advanced aliens from another planet who have mastered the science of time travel, and they are coming here either to observe us or to carry out other intentions.
  3. They are secret government (United States or any government) experimental spacecraft, and by some accounts they are reverse engineered from advanced alien spacecraft in the government’s possession.

In my estimation, the ninety-page 1999 French COMETA study (the English translation stands for“Committee for In-Depth Studies”) is the most authoritative source of UFO information and provides a thoughtful, balanced view. Here are the facts that led me to this position:

  • The COMETAmembership consisted of an independent group of mostly former “auditors” (i.e., defense and intelligence analysts) at the Institute of Advanced Studies for National Defense, or IHEDN, a high-level French military think tank, and by various other highly qualified experts. The independence of the group lends credence that the findings and conclusions would not be censored.
  • The French government did not sponsor it. This lends credence that the COMETA members were objective and not politically guided.
  • The COMETA study was carried out over several years. This lends credence that the COMETA study is a thorough account of UFO phenomena, not a hastily put out government press release.

The 1999 COMETA study concluded:

  1. About 5% of the UFO cases studied were inexplicable.
  2. The best hypothesis to explain them was the extraterrestrial hypothesis (ETH), but they acknowledged this is not the only possible hypothesis.
  3. The authors accused the US government of engaging in a massive cover-up of UFO evidence.

According to the 1999 COMETA study, a small but significant percentage of UFOs are likely of extraterrestrial origin. You will find an English translation of the 1999 COMETAstudy at this website address: http://www.ufoevidence.org/newsite/files/COMETA_part2.pdf.

Based on the above information, the answer to the subject question (i.e., Is There Any Scientific Evidence UFO’s Are Real?) is no. However, the COMETA study goes a long way in establishing UFO’s as a phenomena worthy of scientific study.

A surreal, glowing clock surrounded by swirling golden particles and abstract light patterns in a dark background.

Can Time Travel Be Used as a Weapon?

Categories, Physics, Technology, Threats to Humankind, Time Travel, , ,

Time travel will be the ultimate weapon. With it, any nation can write its own history, assure its dominance, and rule the world. However, having the ultimate weapon also carries the ultimate responsibility. How it is used will determine the fate of humankind. These are not just idle words. This world, our Earth, is doomed to end. Our sun will eventually die in about five billion years. Even if we travel to another Earth-like planet light-years away, humankind is doomed. The universe grows colder each second as the galaxies accelerate away from one another faster than the speed of light. The temperature in space, away from heat sources like our sun, is only about 3 degrees Kelvin (water freezes at 273 Kelvin) due to the remnant heat of the big bang, known as the cosmic microwave background. As the universe’s acceleration expands, eventually the cosmic microwave background will disperse, and the temperature of the universe will approach absolute zero (-273 degrees Kelvin). Our galaxy, and all those in our universe, will eventually succumb to the entropy apocalypse (i.e., “heat death”) in a universe that has become barren and cold. If there is any hope, it lies in the technologies of time travel. Will we need to use a traversable wormhole to travel to a new (parallel) universe? Will we need to use a matter-antimatter spacecraft to be able to traverse beyond this universe to another?

I believe the fate of humankind and the existence of the universe are more fragile than most of us think. If the secrets of time travel are acquired by more than one nation, then writing history will become a war between nations. The fabric of spacetime itself may become compromised, hastening doomsday. Would it be possible to rip the fabric of spacetime beyond a point that the arrow of time becomes so twisted that time itself is no longer viable? I do not write these words to spin a scary ghost story. To my mind, these are real dangers. Controlling nuclear weapons has proved difficult, but to date humankind has succeeded. Since Fat Man, the last atomic bomb of World War II, was detonated above the city of Nagasaki, there has been no nuclear weapon detonated in anger. It became obvious, as nations like the former Soviet Union acquired nuclear weapons, that a nuclear exchange would have no winners. The phrase “nuclear deterrence” became military doctrine. No nation dared use its nuclear weapons for fear of reprisal and total annihilation.

What about time travel? It is the ultimate weapon, and we do not know the consequences regarding its application. To most of humankind, time travel is not a weapon. It is thought of a just another scientific frontier. However, once we cross the time border, there may be no return, no do-over. The first human time travel event may be our last. We have no idea of the real consequences that may ensue.

Rarely does regulation keep pace with technology. The Internet is an example of technology that outpaced the legal system by years. It is still largely a gray area. If time travel is allowed to outpace regulation, we will have a situation akin to a lighted match in a room filled with gasoline. Just one wrong move and the world as we know it may be lost forever. Regulating time travel ahead of enabling time travel is essential. Time travel represents humankind’s most challenging technology, from every viewpoint imaginable.

What regulations are necessary? I have concluded they need to be simple, like the nuclear deterrence rule (about thirteen words), and not like the US tax code (five million words). When you think about it, the rule of nuclear deterrence is simple: “If you use nuclear weapons against us, we will retaliate, assuring mutual destruction.” That one simple rule has kept World War III from happening. Is there a similar simple rule for time travel?

I think there is one commonsense rule regarding time travel that would assure greater safety for all involved parties. I term the rule “preserve the world line.” Why this one simple rule?

Altering the world line (i.e., the path that all reality takes in four-dimensional spacetime) may lead to ruination. We have no idea what changes might result if the world line is disrupted, and the consequences could be serious, even disastrous.

The preserve the world line rule is akin to avoiding the “butterfly effect.” This phrase was popularized in the 2004 film The Butterfly Effect, with the now famous line: “It has been said that something as small as the flutter of a butterfly’s wing can ultimately cause a typhoon halfway around the world.” Although the line is from a fictional film, the science behind it is chaos theory, which asserts there is a sensitive dependence on the initial conditions of a system that could result in a significant change in the system’s future state. Edward Lorenz, American mathematician, meteorologist, and a pioneer of chaos theory, coined the phrase “butterfly effect.” For example, the average global temperature has risen about one degree Fahrenheit during the last one hundred years. This small one-degree change has caused the sea levels around the world to rise about one foot during the same period. Therefore, I believe, it is imperative not to make even a minor change to the past or future during time travel until we understand the implications.

Based on the above discussion, the implications of using time travel as a weapon are enormous. However, if time travel is used as a a weapon, we have no idea how this may impact the world line. If it is possible to adhere to the preserve the world line rule, traveling in time may become safe. Remember, our first nuclear weapons were small compared to today’s nuclear weapons. Even though they were comparatively small, the long-term effects included a 25% increase in the cancer rate of survivors during their lifetime. We had no idea that this side effect would result. Similarly, we have no idea what the long-term effects will be if we alter the world line. We already know from laboratory experiments that the arrow of time can be twisted. Things done in the future can alter the past. Obviously, altering the past may alter the future. We do not know much about it because we have not time traveled in any significant way. Until we do, preserving the world line makes complete sense.

Close-up of an antique clock face showing the time at 11:55 with Roman numerals and a warm, golden glow.

Is Time Real Or Just a Construct of Our Mind?

Categories, Physics, Time Travel, Universe Mysteries, , , , , , ,

Philosophers have debated the nature of time for over 2500 years, and have left us with three principal theories, listed below in no particular order:

1) Presentists Theory of Time—The “presentists” philosophers argue that present objects and experiences are real. The past and future do not exist. This would argue that time is an emerging concept, and exists in our minds.

2) Growing-Universe Theory of Time—The “growing-universe” philosophers argue that the past and present are real, but the future is not. Their reasoning is the future has not occurred. Therefore, they reason the future is indeterminate, and not real.

3) Eternalism Theory of Time—The “eternalism” philosophers believe that there are no significant differences among present, past, and future because the differences are purely subjective. Observers at vastly different distances from an event would observe it differently because the speed of light is finite and constant. The farthest-away observer may be seeing the birth of a star while the closest observer may be seeing the death of the same star. In effect, the closest observer is seeing what will be the future for the farthest-away observer.

Now let us ask what does science have to say about time and start by discussing 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.

Although the above experimental results are relatively new, the classic double slit experiment implies exactly the same conclusion, namely future measurements can influence past behavior. For those of you not familiar with the double slit experiment, a brief synopsis is provided below.

There are numerous versions of the double-slit experiment. In its classic version, a coherent light source, for example a laser, illuminates a thin plate containing two open parallel slits. The light passing through the slits causes a series of light and dark bands on a screen behind the thin plate. The brightest bands are at the center, and the bands become dimmer the farther they are from the center. The series of light and dark bands on the screen would not occur if light were only a particle. If light consisted of only particles, we would expect to see only two slits of light on the screen, and the two slits of light would replicate the slits in the thin plate. Instead, we see a series of light and dark patterns, with the brightest band of light in the center, and tapering to the dimmest bands of light at either side of the center. This is an interference pattern and suggests that light exhibits the properties of a wave. We know from other experiments, for example the photoelectric effect, that light also exhibits the properties of a particle. Thus, light exhibits both particle- and wavelike properties. This is termed the dual nature of light. This portion of the double-slit experiment simply exhibits the wave nature of light. Perhaps a number of readers have seen this experiment firsthand in a high school science class.

The above double-slit experiment demonstrates only one element of the paradoxical nature of light, the wave properties. The next part of the double-slit experiment continues to puzzle scientists. There are five aspects to the next part.

1. Both individual photons of light and individual atoms have been projected at the slits one at a time. This means that one photon or one atom is projected, like a bullet from a gun, toward the slits. Surely, our judgment would suggest that we would only get two slits of light or atoms at the screen behind the slits. However, we still get an interference pattern, a series of light and dark lines, similar to the interference pattern described above. Two inferences are possible:

a. The individual photon light acted as a wave and went through both slits, interfering with itself to cause an interference pattern.
b. Atoms also exhibit a wave-particle duality, similar to light, and act similarly to the behavior of an individual photon light described (in part a) above.

2. Scientists have placed detectors in close proximity to the screen to observe what is happening, and they find something even stranger occurs. The interference pattern disappears, and only two slits of light or atoms appear on the screen. What causes this? Quantum physicists argue that as soon as we attempt to observe the wavefunction of the photon or atom, it collapses. Please note, in quantum mechanics, the wavefunction describes the propagation of the wave associated with any particle or group of particles. When the wavefunction collapses, the photon acts only as a particle.

3. If the detector (in number 2 immediately above) stays in place but is turned off (i.e., no observation or recording of data occurs), the interference pattern returns and is observed on the screen. We have no way of explaining how the photons or atoms know the detector is off, but somehow they know. This is part of the puzzling aspect of the double-slit experiment. This also appears to support the arguments of quantum physicists, namely, that observing the wavefunction will cause it to collapse.

4. The quantum eraser experiment—Quantum physicists argue the double-slit experiment demonstrates another unusual property of quantum mechanics, namely, an effect termed the quantum eraser experiment. Essentially, it has two parts:

a. Detectors record the path of a photon regarding which slit it goes through. As described above, the act of measuring “which path” destroys the interference pattern.
b. If the “which path” information is erased, the interference pattern returns. It does not matter in which order the “which path” information is erased. It can be erased before or after the detection of the photons.

This appears to support the wavefunction collapse theory, namely, observing the photon causes its wavefunction to collapse and assume a single value.

5. If the detector replaces the screen and only views the atoms or photons after they have passed through the slits, once again, the interference pattern vanishes and we get only two slits of light or atoms. How can we explain this? In 1978, American theoretical physicist John Wheeler (1911–2008) proposed that observing the photon or atom after it passes through the slit would ultimately determine if the photon or atom acts like a wave or particle. If you attempt to observe the photon or atom, or in any way collect data regarding either one’s behavior, the interference pattern vanishes, and you only get two slits of photons or atoms. In 1984, Carroll Alley, Oleg Jakubowicz, and William Wickes proved this experimentally at the University of Maryland. This is the “delayed-choice experiment.” Somehow, in measuring the future state of the photon, the results were able to influence their behavior at the slits. In effect, we are twisting the arrow of time, causing the future to influence the past. Numerous additional experiments confirm this result.

Let us pause here and be perfectly clear. Measuring the future state of the photon after it has gone through the slits causes the interference pattern to vanish. Somehow, a measurement in the future is able to reach back into the past and cause the photons to behave differently. In this case, the measurement of the photon causes its wave nature to vanish (i.e., collapse) even after it has gone through the slit. The photon now acts like a particle, not a wave. This paradox is clear evidence that a future action can reach back and change the past.

To date, no quantum mechanical or other explanation has gained widespread acceptance in the scientific community. We are dealing with a time travel paradox that illustrates reverse causality (i.e., effect precedes cause), where the effect of measuring a photon affects its past behavior. This simple high-school-level experiment continues to baffle modern science. Although quantum physicists explain it as wavefunction collapse, the explanation tends not to satisfy many in the scientific community. Irrefutably, the delayed-choice experiments suggest the arrow of time is reversible and the future can influence the past.

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. If that is true, we can argue time has a physical reality. In other words, it is not a construct of our mind. The reality of time implies that actions in the past can influence the future and actions in the future can influence the past. If time were simply a mental construct, it would not be possible for future events to influence the past.

One last point, none of the above negates Einstein’s view of reality consisting of four-dimensional space-time. All aspects of relativity continue to apply. The above article is intended to substantiate that nature of time itself is a physical reality and not a mental or mathematical construct.

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

Stephen Hawking’s Chronology Protection Conjecture’s Impact On Time Travel Science

Categories, Physics, Time Travel, , ,

Most of the scientific community agrees that time travel is theoretically possible, based on Einstein’s special and general theories of relativity. However, world-famous cosmologist and physicist Stephen Hawking published a 1992 paper, “Chronology Protection Conjecture,” in which he stated the laws of physics do not allow the appearance of closed timelike curves (i.e., time travel to the past). Since its publication, the chronology protection conjecture has been significantly criticized. Most of the criticism centered on Dr. Hawking’s use of semiclassical gravity, versus using quantum gravity, to make his arguments. Dr. Hawking acknowledged, in 1998, that portions of the criticism are valid.

However, not to take sides on this issue, I feel compelled to point out that the two fundamental pillars of modern science, namely, general relativity and quantum mechanics, are incompatible. This placed Dr. Hawking in a difficult position regarding the use of gravity in writing the chronology protection conjecture. General relativity and quantum mechanics do not come together to provide a quantum gravity theory. This argues that we still do not have the whole picture, which makes it difficult to completely rule out Dr. Hawking’s chronology protection conjecture.

Currently, there is no widespread consensus on any theory that unifies general relativity with quantum mechanics. If such a theory existed, it would be the theory of everything (TOE) and would provide us with a quantum gravity theory. Highly regarded physicists, such as Stephen Hawking, believe M-theory (i.e., membrane theory), which is the most comprehensive string theory, is a candidate for the theory of everything. However, there is significant disagreement in the scientific community. Many physicists argue that M-theory is not experimentally verifiable, and on that basis is not a valid theory of science. However, to be fair to all sides, Einstein’s special theory of relativity, published in 1905, was also not experimentally verifiable for years. Today, most of the scientific community views the special theory of relativity as science fact, having withstood over one hundred years of scientific investigation. The scientific community, which didn’t really know what to make of the special theory of relativity in 1905, hails it now as the “gold standard” of theories, arguing that other theories must measure up to the same standards of rigorous investigation. I think science is better served by a more moderate position. In this regard, I agree with prominent physicist and author Michio Kaku, who stated in Nina L. Diamond’s Voices of Truth (2000), “The strength and weakness of physicists is that we believe in what we can measure. And if we can’t measure it, then we say it probably doesn’t exist. And that closes us off to an enormous amount of phenomena that we may not be able to measure because they only happened once. The Big Bang is an example. That’s one reason why they scoffed at higher dimensions for so many years. Now we realize that there’s no alternative.”

In essence, we need to keep an open mind, regardless of how bizarre a scientific theory may first appear. However, we need to balance our open-mindedness with experimental verification. This, to my mind, is how science advances.

science of time & time dilation

Will Time Have Meaning in the Post Singularity World? Part 1/3

Artificial Intelligence, Categories, Physics, Technology, Time Travel, Universe Mysteries, , , ,

Will time have meaning in the post singularity world? Let’s start by understanding terms. The first term we will work at understanding is “time.”

Almost everyone agrees that time is a measure of change, for example, the ticking of a clock as the second hand sweeps around the dial represents change. If that is true, time is a measure of energy because energy is required to cause change. Numerous proponents of the “Big Bang” hold that the Big Bang itself gave birth to time. They argue that prior to the Big Bang, time did not exist. This concept fits well into our commonsense notion that time is a measure of change.

Our modern conception of time comes from Einstein’s special theory of relativity. In this theory, the rates of time run differently, depending on the relative motion of observers, and their spatial relationship to the event under observation. In effect, Einstein unified space and time into the concept of space-time. According to this view of time, we live on a world line, defined as the unique path of an object as it travels through four-dimensional space-time, rather than a timeline. At this point, it is reasonable to ask: what is the fourth dimension?

The fourth dimension is often associated with Einstein, and typically equated with time. However, it was German mathematician Hermann Minkowski (1864-1909), who enhanced the understanding of Einstein’s special theory of relativity by introducing the concept of four-dimensional space, since then known as “Minkowski space-time.”

In the special theory of relativity, Einstein used Minkowski’s four dimensional space—X1, X2, X3, X4, where X1, X2, X3 are the typical coordinates of the three dimensional space—and X4 = ict, where i = square root of -1, c is the speed of light in empty space, and t is time, representing the numerical order of physical events measured with “clocks.” (The mathematical expression i is an imaginary number because it is not possible to solve for the square root of a negative number.) Therefore, X4 = ict, is a spatial coordinate, not a “temporal coordinate.” This forms the basis for weaving space and time into space-time. However, this still does not answer the question, what is time? Unfortunately, no one has defined it exactly. Most scientists, including Einstein, considered time (t) the numerical orders of physical events (change). The forth coordinate (X4 = ict) is considered to be a spatial coordinate, on equal footing with X1, X2, and X3 (the typical coordinates of three-dimensional space).

However, let’s consider a case where there are no events and no observable or measurable changes. Does time still exist? I believe the answer to this question is yes, but now time must be equated to existence to have any meaning. This begs yet another difficult question: How does existence give meaning to time?

We are at a point where we need to use our imagination and investigate a different approach to understand the nature of time. This is going to be speculative. After consideration, I suggest understanding the nature of time requires we investigate the kinetic energy associated with moving in four dimensions. The kinetic energy refers to an object’s energy due to its movement. For example, you may be able to bounce a rubber ball softly against a window without breaking it. However, if you throw the ball at the window, it may break the glass. When thrown hard, the ball has more kinetic energy due to its higher velocity. The velocity described in this example relates to the ball’s movement in three-dimensional space (X1, X2, and X3). Even when the ball is at rest in three-dimensional space, it is it still moving in the fourth dimension, X4. This leads to an interesting question. If it is moving in the fourth dimension, X4, what is the kinetic energy associated with that movement?

To calculate the kinetic energy associated with movement in the fourth dimension, X4, we use relativistic mechanics, from Einstein’s special theory of relativity and the mathematical discipline of calculus. Intuitively, it seems appropriate to use relativistic mechanics, since the special theory of relativity makes extensive use of Minkowski space and the X4 coordinate, as described above. It provides the most accurate methodology to calculate the kinetic energy of an object, which is the energy associated with an object’s movement.

If we use the result derived from the relativistic kinetic energy, the equation becomes:

KEX4 = -.3mc2

Where KEX4is the energy associated with an object’s movement in time, m is rest mass of an object, and c is the speed of light in a vacuum.

For purposes of reference, I have termed this equation, KEX4 = -.3mc2, the “Existence Equation Conjecture.” (Note: With the tools of algebra, calculus, and Einstein’s equation for kinetic energy, along with the assumption that the object is at rest, the derivation is relatively straightforward. The complete derivation is presented in my books, Unraveling the Universe’s Mysteries, appendix 1, and How to Time Travel, appendix 2.)

According to the existence equation conjecture, existence (i.e., movement in time) requires negative kinetic energy. This is fully consistent with our observation that applying (positive) kinetic or gravitational energy to elementary particles extends their existence. There may also be a relationship between entropy (a measure of disorder) and the Existence Equation Conjecture. What is the rationale behind this statement? First, time is a measure of change. Second, any change increases entropy in the universe. Thus, the universe’s disorderliness is increasing with time. If we argue the entropy of the universe was at a minimum the instant prior to the Big Bang—since it represented an infinitely dense-energy point prior to change—then all change from the Big Bang on, served to increase entropy. Even though highly ordered planets and solar systems formed, the net entropy of the universe increased. Thus, any change, typically associated with time, is associated with increasing entropy. This implies that the Existence Equation Conjecture may have a connection to entropy.

What does all of the above say about the nature of time? If we are on the right track, it says describing the nature of time requires six crucial elements, all of which are simultaneously true.

  1. Time is change. (This is true, even though it was not true in our “thought experiment” of an isolated atom at absolute zero. As mentioned above, it is not possible for any object to reach absolute zero. The purpose of the thought experiment was to illustrate the concept of “existence” separate from “change.”)
  2. Time is a measure of energy, since change requires energy.
  3. Time is a measure of existence. (The isolated atom, at absolute zero, enables us to envision existence separate from change.)
  4. Movement in time (or existence) requires negative energy.
  5. The energy to fuel time (existence) is enormous. It may be responsible for the life times associated with unstable elementary particles, essentially consuming them, in part, to satisfy the Existence Equation Conjecture. It may be drawing energy from the universe (dark energy). If correct, it provides insight into the nature of dark energy. Essentially the negative energy we call dark energy is required to fuel existence (please see my posts: Dark Matter, Dark Energy, and the Accelerating Universe – Parts 1-4).
  6. Lastly, the enormousness changes in entropy, creating chaos in the universe, may be the price we pay for time. Since entropy increases with change, and time is a measure of change, there appears to be a time-entropy relationship. In addition, entropy proceeds in one direction. It always increases when change occurs. The directional alignment, and the physical processes of time, suggests a relationship between time and entropy.

This view of time is speculative, but fits the empirical observations of time. A lot of the speculation rests on the validity of the Existence Equation Conjecture. Is it valid? As shown in appendix 2 of Unraveling the Universe’s Mysteries (2012) and appendix 2 of How to Time Travel (2013), it is entirely consistent with data from a high-energy particle-accelerator experiment involving muons moving near the speed of light. The experimental results agree closely with predictions of the Existence Equation Conjecture (within 2%). This data point is consistent with the hypothesis that adding kinetic energy can fuel the energy required for existence. The implications are enormous, and require serious scientific scrutiny. I published the Existence Equation Conjecture in the above books to disseminate information, and enable the scientific scrutiny.

The Existence Equation Conjecture represents a milestone. If further evaluation continues to confirm the validity of the Existence Equation Conjecture, we have a new insight into the nature of time. Existence (movement in time) requires enormous negative energy. The Existence Equation Conjecture, itself, provides insight into the physical processes underpinning time dilation (i.e., why time slows down when a mass is moving close to the speed of light or is in a high gravitational field). It answers the question why a subatomic particle’s life increases with the addition of kinetic or gravitational energy. It offers a solution path to a mystery that has baffled science since 1998, namely the cause of the accelerated expansion of the universe (please see my posts: Dark Matter, Dark Energy, and the Accelerating Universe – Parts 1-4). Lastly, it may contain one of the keys to time travel.

In the next post (part 2), we will explore what the technological singularity and the post singularity world in our quest to determine if time has meaning in the post singularity world.