Tag Archives: how to time travel

Diagram of a double slit experiment setup showing a monochromatic light source, double slit, and interference pattern on a screen.

The Classic Double Slit Experiment Is a 100 Year Old Time Travel Paradox that Continues to Baffles Modern Science

First, let’s define a time travel paradox. It is an occurrence that apparently violates some aspect of causality typically associated with time travel. Many science students are introduced to the oddities of the double slit experiment in an advanced high school science class or in an entry level college science class. The double slit experiment is a paradox that has to do with the the future changing the present or the past. The effect has been known for well over a hundred years. It continues to this day to baffle science.

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. See the figure below:

3-17-2014 3-08-41 AM Double Slit Fig 1 small

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 (see glossary), which I discussed in my first book, Unraveling the Universe’s Mysteries—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:
    1. The individual photon light acted as a wave and went through both slits, interfering with itself to cause an interference pattern.
    2. 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:
    1. 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.
    2. 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.

  1. 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.

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

Aliens and UFOs

Are UFOs Time Travelers from the Future?

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 COMETA membership 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. Does this rule out that they are future generations of humans, visiting the past? In my opinion, it does not. Even the conclusions of the 1999 COMETA study did not rule out this possibility. However, there is no conclusive evidence either way.

You will find an English translation of the 1999 COMETA study at this website address: https://www.ufoevidence.org/newsite/files/COMETA_part2.pdf.

The main questions regarding time travel and UFOs are:

  • Are the UFOs future generations of humans, time traveling back to our past and present?
  • Are the UFOs alien spacecraft, or secret government experimental spacecraft, able to traverse great distances using technologies essential to time travel, like a matter-antimatter propulsion system?

I suggest you read the complete 1999 COMETA study and draw your own conclusions.

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

A black and white image of a clock face with a spiral effect distorting the numbers and hands.

Twisting the Arrow of Time

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

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

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

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

Abstract fractal pattern resembling a cosmic or underwater scene with glowing blue and white textures.

How Negative Energy and Time Travel to the Past Are Connected

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

A silhouette of a person with a clock face behind them, symbolizing the concept of time and human existence.

The Greatest Engineering Challenge to Time Travel

Without doubt, harnessing sufficient energy is  the largest obstacle to time travel. For example, time dilation (i.e., forward time travel) is only noticeable when mass approaches a significant fraction of the speed of light or sits in a strong gravitational field. To date, we have been able to accelerate subatomic particles to a point where time dilation becomes noticeable. We have also been able to observe time dilation of a highly accurate atomic clock on a jet plane as it flies over the airport, which contains another atomic clock. Using sensitive instruments, we can measure time dilation. We have also been able to measure time dilation due to differences in the Earth’s gravitational field. However, these differences are only evident using highly accurate atomic clocks. Our human senses are unable to detect a high mounted wall clock moving faster than our wristwatch, which gravitational time dilation predicts is occurring.

The fastest humankind has traveled is 25,000 miles per hour, using the Apollo 10 spacecraft. The speed of light in a vacuum is approximately 186,000 miles per second. This means that a spacecraft would have to go about 13,000 times faster than Apollo 10 for humans to experience noticeable time dilation, or a speed of about 90,000 miles per second, which is roughly half the speed of light. Today’s science has not learned to harness the amount of energy required to accelerate a spacecraft to a velocity of 90,000 miles per second.

Let us consider a simple example to illustrate the amount of energy required to achieve the above velocity. If we have a mass of 1000 kilograms (i.e., 2204 pounds), and we want to accelerate it to 10% the speed of light, the resulting kinetic energy would be about 1017 (i.e., a 1 with 17 zeros after it) joules, whether you calculate the kinetic energy using Newton’s classical formula or Einstein’s relativistic formula for kinetic energy. To put this in perspective, it is more than twice the amount of energy of the largest nuclear bomb ever detonated. It would take a modern nuclear power plant about ten years to output this amount of energy.

The above example gives us a conceptual framework to understand the amount of energy that would be required to accelerate a sizable mass, 1000 kilograms, or 2204 pounds, to just 10% the speed of light. If we wish to accelerate the mass, for example, a spacecraft, to a greater percentage, the energy increases exponentially. For example, to accelerate to 20% the speed of light would require four times the amount of energy.

Today’s engineering is unable to harness this level of energy. In the popular Star Trek television series and movies, the starship Enterprise is able to travel faster than the speed of light using a warp drive, by reacting matter with antimatter. Factually, there is almost no antimatter in the universe. This is one of the mysteries associated with the big bang science theory, which I discussed in my book, Unraveling the Universe’s Mysteries. In theory, during the big bang, matter and antimatter should exist in equal quantities. Our observation of the universe, using our best telescopes, detects almost no antimatter. However, Fermi National Accelerator Laboratory (Fermilab) in Illinois is able to produce about fifty billion antiprotons per hour. This, though, is a miniscule amount compared to the amount needed to power a starship. According to Dr. Lawrence Krauss, a physicist and author of The Physics of Star Trek, it would take one hundred thousand Fermilabs to power a single lightbulb. In essence, we are a long way from using matter-antimatter as a fuel. In addition, the Enterprise was able to warp space. This provided a means to skirt around Einstein’s well-established special theory of relativity, which asserts no mass can travel faster than the speed of light. There is no similar physical law that prohibits space from expanding faster than the speed of light. If we are able to manipulate space, similar to our discussion of the Alcubierre drive in the previous chapter, then scientifically the spacecraft could collapse space in front of it and expand space behind it. However, the Alcubierre drive requires negative energy. Today’s science is unable to create and harness negative energy in any significant way.

Therefore, topping our list of major scientific obstacles regarding time travel is generating huge amounts of energy, in either positive or negative form.

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