Tag Archives: time travel to the past

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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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How Negative Energy and Time Travel to the Past Are Connected

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Today’s science knows precious little about negative energy. The best example we have of creating negative energy in the laboratory is the Casimir effect, which we briefly discussed previously, but will now discuss in detail. Let us start by discussing the energy associated with a vacuum. Vacuums contain energy. One simple experiment to prove this is to take two electrically neutral metal plates and space them closely together in a vacuum. They will be attracted to each other (i.e., the Casimir effect). At approximately 10 nm (i.e., 1/100,000 meters) separation, the plates experience an attraction force of about one atmosphere (i.e., typically, the pressure we feel at sea level on Earth). What is causing this force?

The energy in a vacuum is termed “vacuum energy.” Surprisingly, it appears to obey the laws of quantum mechanics. For example, the energy will statistically vary within the vacuum. When the vacuum energy statistically concentrates, it gives rise to virtual particles, which is termed a “quantum fluctuation.” When the metal plates are spaced closely, relatively few virtual particles can form between the plates. A much larger population of virtual particles can form around the plates. This larger population of particles exerts a force on the outside of the plates. This force is the Casimir-Polder force, and it pushes the plates together. However, another strange physical phenomenon is also occurring between the closely spaced plates. In quantum mechanics, every particle has a “zero-point energy.” Even a vacuum is said to have a zero-point energy. The zero-point energy, or the “ground state,” is the lowest energy level that a particle or a vacuum may have. By reducing the space between the plates, some physicists believe we are reducing the normal zero point energy of the vacuum between the plates. When this occurs, those physicists argue the vacuum energy between the plates is negative energy (i.e., below the zero-point energy).

The scientific community is not in complete consensus regarding the properties or even the existence of negative energy. Physicists are able to mathematically model negative energy and use those models to make predictions regarding the theoretical behavior of negative energy. While the mathematical models do not prove the existence of negative energy, it is instructive to consider their predictions, and their implications to time travel. Here are the salient features of negative energy based on the mathematical modeling:

• Negative energy implies the existence of negative mass. This, of course, begs a question. What is negative mass? Negative mass is a hypothetical concept in theoretical physics. Anglo-Austrian mathematician and cosmologist Hermann Bondi suggested its existence in 1957. If it exists, it is the negative counterpart of normal (i.e., positive) mass and exhibits unusual properties. For example, normal masses exhibit attractive forces, known as gravitational attraction. Negative masses would exhibit repulsive forces. However, be careful not to equate negative mass with antimatter. The vast majority of the scientific community holds that antimatter is still positive mass. Based on this consensus, they predict antimatter would exhibit the same properties as positive mass. For example, two antimatter particles would exert an attractive force on each other, not a repulsive force. The implications of negative mass on time travel are ambiguous, since the existence of negative mass itself is ambiguous.

• Several in the scientific community suggest that a negative energy vacuum would allow light to travel faster than a normal positive energy vacuum. If this theory proves to be correct, it could have major implications for time travel. For example, there is speculation that this property may allow people to travel faster than the speed of light in a negative-energy vacuum bubble. Previously, we have discussed that as a mass approaches the speed of light, time dilates (i.e., time slows down for the mass). If the mass exceeds the speed of light, the implication is that it can travel into the past. We will discuss this further in the next chapter.

• Stephen Hawking and other physicists suggest that negative energy is required to stabilize a “traversable wormhole,” an entity that would allow a person, object, or information to travel between two points in time or space. Wormholes are a hypothetical shortcut between two points in time or two points in space. There are solutions to Einstein’s general equations of relativity suggesting the theoretical existence of wormholes. However, we have no observational evidence that they exist in reality.

Until we can find a way to produce negative energy and apply it experimentally to determine its effect on time, we can only speculate.

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

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The Mallett Time Machine – Time Travel to the Past May Become Possible!

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Thanks to particle accelerators, like the Large Hadron Collider (LCH) 175 meters (574 ft) beneath the Franco-Swiss border near Geneva, Switzerland, physicist have been able to routinely demonstrate forward time travel (i.e., time dilation) using subatomic particles. In a sense, you can think of the Large Hadron Collider as a time machine. It is capable of sending subatomic particles to the future. Unfortunately, we do not have a similar machine that can send subatomic particles to the past. However, Dr. Ronald Mallett is attempting to change that.

Dr. Ronald Mallett is an American theoretical physicist and the author of Time Traveler: A Scientist’s Personal Mission to Make Time Travel a Reality (2007). Dr. Mallett is a full professor at the University of Connecticut, where he has taught physics since 1975.

Dr. Mallett is attempting to twist spacetime using a ring laser (i.e., a laser that rotates in a circle) by passing it through a through a photonic crystal (i.e., a crystal that only allows photons of a specific wavelength to pass through it). The concept behind spacetime twisting by light (STL) is that by twisting space via the laser, closed timelike curves will result (i.e., time will also be twisted). In this way, Dr. Mallett hopes to observe a violation of causality when a neutron is passed through the twisted spacetime. Dr. Mallett also believes he will be able to send communication by sending subatomic particles that have spin up and spin down. Note, the spin of a subatomic particle is part of the particle’s quantum description. As a simple example, we can consider spin up equal to 1 and spin down equal to 0. Using this technique, Dr. Mallett can send a binary code, similar to the binary codes used in computing.

Few scientists openly discuss their work on time machines. They fear ridicule. In this regard, Dr. Mallett is a pioneer. When Dr. Mallett was ten years old, his father died at age thirty-three from a heart attack. Dr. Mallett has shared that his initial drive to invent a time machine was to go back in time and visit with his father. Unfortunately, the science of time travel only allows a person to go back in time to the point when the time machine is first turned on. Dr. Mallett acknowledges this, but continues his quest.

Dr. Mallett’s concept of twisting space is close to the concept of creating a wormhole, as discussed in my last post. Dr. Mallett is using laser light as means of creating the mouth of the wormhole. In a publication (R. L. Mallett, “The Gravitational Field of a Circulating Light Beam,” Foundations of Physics 33, 1307–2003), Dr. Mallett argued that with sufficient energies, the circulating light beam might produce closed timelike lines (i.e., time travel to the past).

Is Dr. Mallett’s theoretical foundation solid? According to physicists Dr. Olum and Dr. Everett, it is fatally flawed. In a paper published in 2005 (Ken D. Olum and Allen Everett, 2005, “Can a Circulating Light Beam Produce a Time Machine?”, Foundations of Physics Letters 18 (4): 379–385), they argue three points:

  1. Dr. Mallett’s analysis contains unusual spacetime (i.e., mathematical) issues, even when the power to the machine is off.
  2. The energy required to twist spacetime would need to be much greater than lasers available to today’s science.
  3. They note a theorem proven by Stephen Hawking (chronology protection conjecture—1992), namely, it is impossible to create closed timelike curves in a finite region without using negative energy.

Although Dr. Mallett did not address their criticism in a formal publication, he did argue in his book, Time Traveler, that he was forced to simplify the analysis due to difficulties in modeling the photonic crystal. This, however, is far from a complete response.

Who is right? In the physical sciences, we are judged by the weakest link in our theories. If I use this criterion, I would say the argument favors Dr. Mallett, since the chronology protection conjecture, which we will discuss in the next chapter, has come under serious criticism, and it is not clear that it presents a valid challenge. Nonetheless, Dr. Olum and Dr. Everett are highly regarded physicists. Therefore, at this point, it is hard to know who is right, and right about what. Perhaps the mathematical analysis is flawed, and the approach published by Dr. Mallett requires more energy than is available via today’s technology. However, we are witnessing a significant event in science. A respected physicist, Dr. Mallett, is openly publishing his work on building a backward time travel machine. Other respected physicists, Dr. Olum and Dr. Everett, are entering into a scientific debate regarding Dr. Mallett’s theoretical basis. From my point of view, this is how it should be in science. The debate is healthy. As a theoretical physicist, I know that the debate will end only when either:

  1. The Mallett time machine works, or
  2. The Mallett time machine enters the rubbish pile of scientific failures, along with astronomer Ptolemy’s Earth-centered model of the solar system and the flat Earth theories.

This material is based on my new book, How to Time Travel.

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Traversable Wormholes – Time Travel to the Past May Be Possible!

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Traversable wormholes may enable time travel to the past. This post is based on material from my new book, How to Time Travel.

Let us begin our discussion by understanding the scientific meaning of a “wormhole.” There are valid solutions to Einstein’s equations of general relativity that suggest it is possible to have a “shortcut” through spacetime. To picture this, consider a piece of paper with a dot at opposite corners. In Euclidean geometry, normally taught in high school, we learn that the shortest distance between the two points is a straight line. However, valid solutions to Einstein’s general relativity equations suggest that the two points on the paper are connectable by an even shorter path, a wormhole. To visualize this, simply fold the opposite corners of the paper with the dots, such that the dots touch. You have created a representation of a wormhole. You have manipulated the space between the dots by folding the paper to allow them to touch.

Unfortunately, there is no scientific evidence that wormholes exist in reality. However, the strong theoretical foundation suggesting wormholes (i.e., valid solutions to Einstein’s equations of general relativity) makes their potential existence impossible to ignore.

The first type of wormhole solution to Einstein’s equations of general relativity was the Schwarzschild wormhole, developed by German physicist Karl Schwarzschild (1873–1916). Unfortunately, although the Schwarzschild mathematical solution was valid, it resulted in an unstable black hole. The unstable nature of the Schwarzschild wormhole suggested it would collapse on itself. It also suggested that the wormhole would only allow passage in one direction. This brought to light an important new concept. Faced with the unstable nature of Schwarzschild wormholes, American theoretical physicist Kip Thorne and his graduate student Mike Morris demonstrated a general relativity “traversable wormhole” in a 1988 paper. In this mathematical context, a traversable wormhole would be both stable and allow information, objects, and even humans to pass through in either direction and remain stable (i.e., would not collapse on itself). As is often the case in science, one discovery leads to another. Numerous other wormhole solutions to the equations of general relativity began to surface, including one in 1989 by mathematician Matt Visser that did not require negative energy to stabilize it.

As discussed above, traversable wormholes may require negative energy to sustain them. Several prominent physicists, including Kip Thorne and British theoretical physicist/cosmologist Stephen Hawking, believe the Casimir effect proves negative energy densities are possible in nature. Currently, physicists are using the Casimir effect in an effort to create negative energy. Obviously, if successful, the amounts of negative energy will likely be small. Because of the amount of negative energy that may result, I suspect the first wormholes developed will be at the quantum level (i.e., the level of atoms and subatomic particles).

We have merely scratched the surface regarding the science of wormholes, but we did accomplish one important objective. We have described how a traversable wormhole would allow spacetime travel via shortcuts in spacetime. This means we could connect two points in time or two points in space via a traversable wormhole. However, there is a hitch regarding time travel to the past. According to the theory of relativity, we cannot go back to a time before the wormhole existed. This means that if we discover how to make a traversable wormhole today, a year from now we can go back to today.

You may wonder why a wormhole constructed today would not allow us to go back to yesterday. To understand this conundrum, we need to understand just how a wormhole works as a time machine. Here is one scenario. Imagine you are able to accelerate one end of a wormhole to a significant fraction of the speed of light. Perhaps you could use a high-energy ring laser (i.e., a laser than rotates in a circle). As you twist the space, you create the “mouth” of the wormhole, something like a tunnel. After you enter the mouth of the wormhole, you are now somewhere in the wormhole’s “throat.” A “tunnel” is a good analogy to what is occurring. Now imagine you are able to take the other entrance of the tunnel, which is at rest and called the “fixed end,” and bring it back close to the origin. Time dilation causes the mouth to age less than the fixed end. A clock at the mouth of the wormhole, where spacetime accelerates near the speed of light, will move slower than a clock at the fixed end.

Given the above understanding of how a wormhole acts as a time machine, let us address why it is only possible to go back to the time of the wormhole’s construction. Imagine you have two synchronized clocks. If you place one clock at the mouth, and you place the other clock at the fixed end, they will initially read exactly the same time, for example, the year 2013. However, the clock at the mouth, influenced by the twisted space, is going to experience time dilation, and therefore move slower than the clock at the fixed end. Let us consider the case where the clock at mouth of the wormhole moves, based on the rate of twisting spacetime, one thousand times slower than the clock at the fixed end. In one hundred years, the clock at the fixed end, which experiences no time dilation, will read 2113. The clock at the mouth will still read 2013; only one tenth of one year will have passed due to time dilation at the mouth of the wormhole. From the fixed end, where no time dilation is occurring (i.e., the clock reads 2113), you can walk back to the mouth of the wormhole, where the clock still reads 2013. You will have walked one hundred years into the past. Notice, though, you cannot go back beyond the time of the traversable wormhole’s construction.

This post is based on material from my new book, How to Time Travel. Click How to Time Travel to browse the book free on Amazon.

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How to Time Travel: Explore the Science, Paradoxes, and Evidence

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Here is the entire introduction from my new book, How to Time Travel. Enjoy!

Introduction

Few subjects evoke more emotion than time travel, the concept of moving between different points in time in a manner analogous to moving between different points in space. Humankind’s fascination with time travel dates back thousands of years. Although there is no consensus recognizing which written work was the first to discuss time travel, many scholars argue that the Mahabharata, from Hindu mythology, is the first, dating between 700 BCE (Before the Common/Current/Christian Era) and 300 CE (Common/Current/Christian Era). The Mahabharata, which is one of the two major Sanskrit epics of ancient India, relates the story of King Revaita, who travels to heaven to meet the deity Brahma. When King Revaita returns to Earth, he is shocked to learn that many ages have passed. In today’s science, we would assert King Revaita experienced time dilation.

What is time dilation? It is a scientific fact that time moves slower for any mass accelerated near the speed of light. If that mass were a clock, for example, the hands of the clock would appear to be moving slower than a clock in the hand of an observer at rest. That phenomenon is termed time dilation. If King Revaita used a spaceship capable of speeds near the speed of light to visit Brahma, a roundtrip journey that would appear to King Revaita to take one year would result in a time passage of thirty years on Earth. This may seem like science fiction, but time dilation is a well-established, experimentally verified aspect of Einstein’s special theory of relativity; more about this later.

Arguably, the greatest single written work that laid the foundation to fire the imagination of today’s generation regarding time travel is H. G. Wells’s classic novel, The Time Machine, published in 1895. It has inspired numerous popular movies, television programs, novels, and short stories. Why are we humans so obsessed with time travel? It appears to be an innate longing. How many times have you wished that you could go back to a specific point in time and select a different action? We all do it. Consider the number of times you have replayed a specific situation in your mind. Psychologists tell us we replay an event in our minds when the outcome is not finished to our satisfaction. This has accounted for numerous nights of tossing and turning. Another common need is to seek answers to important questions from a firsthand perspective. Perhaps you would like to be a witness during the resurrection of Christ, or be a witness behind the grassy knoll during the Kennedy assassination. Perhaps you miss a loved one who has passed on, and you would like to go back in time to embrace that loved one again.

Some of us also dream about time travel to the future. What outcomes will result from our decisions? Imagine the prosperity and happiness that could be ours if we were able to travel to the future. We would be able to witness the outcome of any decision, return to the present, and guide our lives accordingly. Picking the right profession or choosing the right mate would be a certainty. We could ensure there would be no missteps in our life. A life of leisure and prosperity would be ours for the taking.

It is little wonder that many people ask this deceptively simple question: Is time travel possible? The majority of the scientific community, including myself, says a resounding yes. The theoretical foundation for time travel, based on the solutions to Einstein’s equations of relativity, is widely accepted by the scientific community. The next question, which is the most popular question, is how to time travel. Of all the questions in science, the keyword phrase “how to time travel” is close to the top of Internet search engine searches. According to Google, the largest search engine in the world, there are 2,240,000 worldwide monthly searches for the keyword phrase “how to time travel,” as of this writing. Unfortunately, it is the most difficult question to answer.

Obviously, interest in time travel is high, and what people want to know most is how to time travel. This high interest, combined with the intriguing real science behind time travel, is what inspired me to write this book.

At this point, I would like to set your expectations. We are going to embark on a marvelous journey. We will examine the real science of time travel, the theoretical foundation that has most of the scientific community united that time travel is possible. We will also examine the obstacles to time travel, and there are many. However, even in the face of all the obstacles, most of the scientific community agrees it is theoretically possible to time travel. The largest issue in time travel is not the theoretical science. It is the engineering. Highly trained theoretical physicists understand the theoretical science of time travel. However, taking the theory and building a time machine capable of human time travel has proved a formidable engineering task. It has not been done, but we are amazingly close. We have already built time machines capable of sending subatomic particles into the future. If you will pardon the pun, it is just a matter of time before we engineer our way through the time travel barrier and enable human time travel.

In setting your expectations, I promise you significant insight into the real science of time travel and an equally incredible insight into the obstacles to time travel. I cannot promise that with this knowledge you will be able to overcome the obstacles and engineer how to time travel. However, you may be the one person destined to harness the science, glean the engineering simplicity, and journey in time. There is only one way to find out, namely, read on.

To browse the book free on Amazon, click this link: http://amzn.to/1dWyEkp

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Is Humankind Ready for Time Travel?

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There is a high probability that scientists will unlock the secrets to human time travel before the end of this century. The technologies needed to develop a real time machine are already coming together.

Let us consider forward time travel, also known as “time dilation”. Particle colliders, like the CERN Large Hadron Collider, are routinely able to accelerate subatomic particles, like a muon (i.e. a negatively charged particle about two hundred times heavier than an electron), and cause time dilation (i.e. extend the life span of the particle by a factor of ten or more). How does this relate to human time travel?

It is a scientific fact that humans within a spacecraft traveling at a velocity near the speed of light would experience time dilation (i.e. forward time travel). A one-year journey, measured on a clock onboard the spacecraft, would be equivalent to decades on Earth. One technology envisioned to power such a spacecraft is a matter-antimatter propulsion engine. CERN scientists, using the Large Hadron Collider, are able to produce and store small quantities of antimatter. The United States Air Force has been funding antimatter research since the early 1960’s. If this research is successful, it could result in a spacecraft with a matter-antimatter propulsion engine, capable of velocities we can only read about in science fiction.

Time travel to the past may be just a decade away, according to Dr. Ronald Mallett, an American theoretical physicist, author, and full professor at University of Connecticut. Dr. Mallett is attempting to twist spacetime using a ring laser (i.e. a laser that rotates in a circle) by passing it through a through a photonic crystal (i.e. a crystal that only allows photons of a specific wavelength to pass through it). The concept behind “Spacetime Twisting by Light” is that by twisting space, via the laser, closed timelike curves will result (i.e. time will also be twisted). A closed timelike curve means that an object, like a neutron (i.e. a subatomic particle), will be able to travel backward in time. Dr. Mallett’s work is still in the research stage, but it represents serious time travel research by a solid member of the scientific community.

While all signs point to humankind having the ability to travel in time by the end of this century, will humankind be ready for time travel?

Most people think of time travel as either science fiction or just another frontier of science. Few realize the weapon potential of time travel. However, it is the ultimate weapon. Any government capable of enabling human time travel can dominate the world. That government can control history. If they can control history, they can control their future. The government’s agents, the time travelers, can intervene and change the past. Similarly, time traveling agents to the future will know with certainty the outcome of any event. The need for spies, secret agents, spy satellites, and the like, will become obsolete. The time machine will be the ultimate weapon, time travelers the ultimate soldiers.

If the capability to time travel is acquired by more than one government, wars as we know them will likely cease. In their place, governments will fight over “history”. Each government will seek to write its own history, and assure its future success. The “world line” (i.e. the four-dimensional path each reality traces in spacetime) will bend and twist to the will of the time machine.

The potential of using time travel as a weapon is real, and we do not know if humankind will be able to control it. If we look to history, humankind has deployed weapons, like nuclear bombs, without knowing the full long-term impact. For example, the Fat Man nuclear bomb detonated above the city of Nagasaki, not only killed 60,000 – 80,000 people in the first four months, but the long-term effects included a 25% increase in the cancer rate of survivors during their lifetime.

There is hope. Humankind recognized the uncontrollable nature of biological weapons before deploying them as weapons of mass destruction. In a 1969 press conference, United States President Richard M. Nixon stated, “Biological weapons have massive, unpredictable, and potentially uncontrollable consequences.” He added, “They may produce global epidemics and impair the health of future generations.” In 1972, President Nixon submitted the Biological Weapons Convention to the U.S. Senate: “I am transmitting herewith, for the advice and consent of the Senate to ratification, the Convention on the Prohibition of the Development, Production, and Stockpiling of Bacteriological (Biological) and Toxin Weapons, and on their Destruction, opened for signature at Washington, London and Moscow on April 10, 1972. The text of this Convention is the result of some three years of intensive debate and negotiation at the Conference of the Committee on Disarmament at Geneva and at the United Nations. It provides that the Parties undertake not to develop, produce, stockpile, acquire or retain biological agents or toxins, of types and in quantities that have no justification for peaceful purposes, as well as weapons, equipment and means of delivery designed to use such agents or toxins for hostile purposes or in armed conflict.”

Will humankind be able to control time travel in a similar fashion to biological weapons? If the answer is yes, then time travel and the associated technologies may serve humankind, assuring humankind’s survival. If the answer is no, the world line may become the new battleground, as each nation seeks to rewrite their history. Would it be possible to twist the world line beyond recognition? Will time itself fall victim to humankind’s carelessness?

With nuclear weapons, the doctrine of nuclear deterrence kept humankind from destroying itself. With time travel, we need a similar doctrine. I submit for your consideration that doctrine needs to be: Preserver the World Line.

Lou Del Monte’s new book, How to Time Travel, is expected to be released on Amazon in early September 2013.