Introduction
You often watch science fiction and wonder if faster-than-light travel or teleportation could ever actually happen. You enjoy the futuristic wonders on your screen, but you suspect that many beloved tropes might violate the fundamental laws of nature.
Lawrence M. Krauss explores how the physics of Star Trek separates real scientific possibilities from science fiction impossibilities. You discover that science fiction writers use plausible physics to hook your imagination while quietly bending the rules to serve the plot.
The book investigates Newtonian mechanics, relativity, quantum mechanics, and cosmology through familiar technological marvels. You learn how the universe operates at its most fundamental level by examining what happens when science fiction pushes against reality.
- Can you ever outrun the speed of light?
- How much energy does it take to run a replicator?
- What happens to your body inside a transporter beam?
1. Newtonian Physics and Space Travel
When a starship accelerates, fusion reactions push gases backward, causing the engines and the ship to recoil forward. The captain's seat exerts a lethal force on the body, preventing blood from flowing to the head and causing unconsciousness and death.
High accelerations without protection would kill a spacecraft crew due to severe G-forces.
Lawrence M. Krauss notes that human physiology cannot handle extreme velocity changes without mechanical aid. You must limit ordinary movement to a 3G maximum acceleration to avoid exceeding safe limits without dampers. Achieving halfemporal speed of light at this rate requires 5 million seconds or about 2.5 months of continuous thrust.
A crew member at the helm of the starship Defiant near Iconia experiences an intense pressure in the chest and loses consciousness because the ship lacks inertial dampers.
Inertial Dampers
To prevent the crew from turning into chunky salsa during rapid accelerations, inertial dampers act as cosmic shock absorbers by setting up an artificial gravitational field that pulls in the opposite direction of the reaction force.
Inertial dampers must create an artificial gravitational field to cancel out reaction forces during acceleration.
The technology requires an astonishing 60 milliseconds response time for the inertial dampers on the Enterprise to protect the personnel.
The Enterprise almost gets destroyed when the microchip life-forms known as Nanites start eating the central-computer-core memory, leading to a loss of inertial dampers.
Tractor Beams and Momentum
According to the laws of motion, pulling something with a rope, grappler, or tractor beam requires an anchor. In the depths of space, a ship attempting to pull another will experience recoil and move toward the target object unless its momentum is compensated.
Pulling an object with a tractor beam in deep space without an anchor causes both objects to move toward each other due to inertia.
Captain Jean-Luc Picard orders Lieutenant Riker to turn off the tractor beam during "The Battle" because the towed ship would continue moving beside them by its own momentum.
2. Relativity and Spacetime
Space, time, and gravity are fundamentally intertwined. Einstein's theories of special and general relativity dictate these constraints.
Special Relativity
As an object approaches the speed of light, time slows down, lengths contract, and mass increases toward infinity. Because the speed of light is constant for all observers regardless of relative motion, space and time become relative. Clocks tick slower, yardsticks shrink, and massive objects get heavier, making light-speed travel for massive bodies impossible.
Atomic clocks carried aloft in high-speed aircraft have been observed to lag behind their terrestrial counterparts.
Starships set normal impulse operation speed limit at 0.25c or 75,000 km/sec. At half the speed of light, clocks slow down and yardsticks shrink by 15 percent. Space shuttle clocks around Earth tick less than one ten-millionth of a percent slower.
Hermann Minkowski demonstrated that space and time are relative projections of an underlying four-dimensional manifold. Relative motion can mix up different observers' notions of space and time while keeping the spacetime distance absolute. Hermann Minkowski introduced four-dimensional spacetime in 1908.
Monocular vision and depth perception illustrate how two observers viewing a ruler from different angles see different two-dimensional projections of a three-dimensional object.
Time travel in science fiction and general relativity creates severe causal paradoxes. Traveling back in time creates loops where an effect can precede its cause, such as killing one's mother before being born or sending binary messages through a severed head to the future before the journey even takes place.
In "Time's Arrow", Picard taps a binary code into Data's severed head in the nineteenth century, which is later reattached by LaForge in the twenty-fourth century.
The first two series featured twenty-two episodes dealing with time travel.
Mathematician Kurt Gödel developed a solution to Einstein's equations involving a uniformly spinning universe where one could travel back in time by moving in a large circle in space.
General relativity allows for closed timelike curves, meaning time travel is theoretically supported by Einstein's equations. The Enterprise gets caught in a temporal causality loop after being hit by the Bozeman emerging from a temporal distortion.
By accelerating to warp speed for an instant, a ship travels faster than light and overtakes the light rays that left it previously. This Picard Maneuver makes it appear in two places at once to an enemy observer using subspace sensors. Jean-Luc Picard became famous for introducing this tactic while stationed aboard the Stargazer.
Curved Spacetime and Time Travel
Astrophysicists noticed that Mercury's perihelion precessed in a way inconsistent with Newtonian gravity. They hypothesized a planet named Vulcan inside Mercury's orbit to perturb it, similar to how Neptune was discovered via Uranus's orbit. Einstein later showed that general relativity's curved space explains the discrepancy without needing Vulcan.
The hypothetical planet Vulcan was suggested to solve the anomalous perihelion precession of Mercury, but it does not exist.
Arthur Eddington confirmed general relativity in 1919 by showing that starlight bends around the Sun twice as much as Newtonian physics predicts. Calculations based on flat space and baseball trajectories predict a certain amount of light bending due to gravity. Sir Arthur Stanley Eddington led an expedition in 1919 to observe star positions near the Sun during a solar eclipse, confirming Einstein's predictions.
General relativity dictates that clocks in stronger gravitational fields tick more slowly. Robert Pound and George Rebka measured gamma radiation frequencies in a Harvard building's basement versus 74 feet higher on the roof in 1960. They found a frequency shift of 1 part in a million billion size, proving clocks run slower closer to the Earth.
GPS devices calculate positions by comparing arrival times of signals from satellites in high orbits. GPS units in modern cars rely on signals from orbiting satellites whose clocks are corrected for gravitational time dilation because these satellites experience different gravitational fields.
Mathematically consistent wormholes in general relativity are transitory and pinch off faster than a traveler can pass through them.
To keep a wormhole's mouth open against gravitational collapse, Kip Thorne argued it must be threaded with exotic material that exerts negative energy, acting gravitationally to blow rather than suck.
Stephen Hawking discovered in 1974 that black holes emit radiation due to quantum fluctuations. Empty space is filled with virtual particle pairs from quantum fluctuations. Near a black hole's event horizon, one virtual particle can fall inward while the other escapes, contributing negative energy that decreases the black hole's mass.
By moving one mouth of a wormhole at high sublight speed through space and returning it, special relativity dictates that its clock will lag behind the stationary mouth. Kip Thorne designed a wormhole time machine scenario where dragging one mouth through space creates a time travel loop, making a date like 9 days earlier visible through the moving wormhole mouth in the author's theoretical example.
Miguel Alcubierre derived a general relativity solution corresponding to warp travel by expanding space behind a spacecraft and contracting it in front. The vessel rides like a surfboard on a wave, staying locally below the speed of light so clocks remain synchronized while globally traversing vast distances instantly. The Enterprise-D reaches warp 9.6 which equals 1909 times the speed of light, before a recalibration sets the warp speed limit to 10.
Nature endows empty space with a non-zero energy known as dark energy, which is three times more significant than all matter in galaxies combined. While it causes the universe's expansion to speed up similarly to Einstein's cosmological constant, it cannot be harnessed for spacecraft propulsion.
3. Atoms Bits and Transporters
Recreating human beings via matter streams forces a choice between physical transport and immense information storage.
Transporting a human involves moving roughly $10^{28}$ atoms. While digital information can be duplicated and transmitted efficiently like books or computer bits, human transport requires either moving the actual atoms or extracting the information and recombining it with matter at the destination.
In the Star Trek episodes The Enemy Within and Second Chances, transporter malfunctions result in individuals being split into two distinct physical copies.
The Cost of Information
Storing the complete information pattern of a human body requires vastly more data capacity than all books ever written. Assuming a conservative estimate of one kilobyte to encode each atom's location and internal state, a human pattern requires $10^{28}$ kilobytes. This exceeds the storage of all books in existence by roughly sixteen orders of magnitude.
Lawrence Maxwell Krauss compares his home computer's storage growth from a 400-kilobyte floppy disk to a 500-gigabyte hard drive over two decades.
If only information is beamed, the original 50-kilogram body's atoms must be destroyed. Using Einstein's formula $E = mc^2$, converting a 50-kilogram person entirely into pure energy would yield an explosive force equivalent to over a thousand 1-megaton hydrogen bombs.
The text references the real-world disappearance of Jimmy Hoffa as a metaphor for the severe disposal problem of leftover matter.
Quantum Limits
The Heisenberg uncertainty principle states that certain pairs of physical observables, such as a particle's position and velocity, cannot both be known with absolute precision. Observing an atom by bouncing high-energy photons off it inevitably alters its speed and direction.
Star Trek writers introduced fictional Heisenberg compensators to bypass this limitation and achieve quantum resolution.
Due to the wave nature of light and diffraction limits, resolving objects at atomic scales across a standard transporter range of 40,000 kilometers using electromagnetic radiation requires using short-wavelength X-rays or gamma rays, and a lens diameter of approximately 50,000 kilometers.
The Keck telescope in Hawaii and Mt. Palomar telescope in California illustrate how larger lenses are needed to resolve fainter and smaller objects.
Matter is held together by electric forces and binding energies. To completely break matter apart into quarks, matter undergoes a phase transition by heating it to about 1000 billion degrees, requiring about 10 percent of the energy needed for full matter-antimatter annihilation.
Fermilab's Tevatron accelerator in Batavia, Illinois, accelerates individual protons to high speeds, but cannot yet melt them into quarks.
Experiments in Vienna successfully destroyed the quantum configuration of a single photon and instantly recreated it elsewhere using quantum entanglement. However, macroscopic human bodies interact constantly with their environment, destroying all quantum entanglements and making quantum teleportation useless for moving people.
IBM placed a full-page advertisement in Rolling Stone Magazine suggesting future teleportation of goulash.
4. Energy Holodecks and Antimatter
Advanced starship power sources and holographic environments require managing extreme energy densities and containment constraints.
Antimatter Propulsion
Because antiprotons and positrons are electrically charged, a properly adjusted magnetic field forces them into circular orbits inside a doughnut-shaped container, preventing them from colliding with solid matter and annihilating. Fermilab uses a large ring of magnets in its Antiproton Source to store antiprotons before steering them into the Tevatron collider. An intense beam of antiprotons strikes protons at Fermilab 400,000 times a second, while the Tevatron high-energy collider ring has a circumference of 4 miles.
When matter and antimatter annihilate, they release pure radiation traveling at the speed of light. The energy of the resulting gamma-ray spike corresponds directly to the rest mass of the annihilated particles. Electron-positron annihilation produces a sharp spike of gamma radiation of 511 keV, while proton-antiproton annihilation produces a rest energy and gamma-ray spike of 1 GeV. In Star Trek, the Enterprise tracked the Crystalline Entity by searching for annihilation radiation, though the writers mistakenly searched for 10 keV instead of the 1 GeV expected from proton-antiproton annihilations.
Because special relativity and quantum mechanics dictate that all particles must have antiparticles, the early universe should have contained equal amounts of both. Calculations of cosmic background radiation reveal that a minuscule initial excess of matter allowed the universe to survive annihilation. Andrei Sakharov proposed in the 1960s that dynamic asymmetry could be generated if three specific conditions were fulfilled in the laws of physics during the early universe. The current ratio in the cosmic background radiation is 1 proton for every 10 billion photons, stemming from an original fractional excess of protons over antiprotons in the early universe of 1 part in 10 billion.
Operating accelerators to produce antiprotons requires immense budgets for electricity, personnel, and infrastructure, resulting in millions of antiprotons per dollar but costing vastly more energy to create than is recovered through annihilation. Consultation with former director John Peoples, Jr. and his staff at Fermilab revealed the exact financial and operational breakdown of producing antiprotons.
Fermilab produces 50 billion antiprotons an hour. Operations run for 6,000 hours at 75 percent efficiency, leading to a total annual production at Fermilab of 300,000 billion antiprotons. Capital cost of Fermilab antiproton components reached $500 million in 1995 dollars, alongside a total annual operating, capital, and administrative cost of $48 million. Current technology yields a wholesale value of 6 million antiprotons for a dollar.
Star Trek depicts matter-antimatter mechanics with fictional workarounds like quantum charge reversal and tunable ratios. The franchise invents devices that flip particle charges with minimal energy loss, handles neutral anti-atoms that defy magnetic containment, and incorrectly varies the matter-antimatter annihilation ratio when physics demands a strict 1:1 ratio. The technical manual claims a 24 percent net energy loss for quantum charge reversal devices. A starship storage pod on Deck 42 holds a total antimatter fuel capacity of 3,000 cubic meters, intended to last a starship mission on full fuel capacity for 3 years. This 3,000 cubic meters of rarefied plasma corresponds to a mass of 5 million grams, while the technical manual incorrectly described varied ratios ranging from 25:1 to 1:1. Wesley Crusher correctly points out in the episode "Coming of Age" that the Starfleet exam question regarding matter-antimatter ratios is a trick question because only a 1:1 ratio is valid.
Star Trek posits that porous dilithium lattices regulate antimatter density and reaction rates, bearing the formal name 2(5)6 dilithium 2(:)1 diallosilicate 1:9:1 heptoferranide. This mirrors pseudoscientific cold fusion arguments assuming that macroscopic chemical structures can directly alter subatomic nuclear reaction scales. During the short-lived cold fusion heyday lasting 6 months, proponents claimed chemical bonding could force atomic nuclei to fuse at room temperature, ignoring that atomic sizes exceed the size of atomic nuclei by a factor of 10,000.
Holographic Technology
Holograms record both the intensity and phase of light waves to reconstruct a three-dimensional visual image.
Dennis Gabor established that splitting a light beam into a reference beam and an object-scattered beam creates an interference pattern on film. Illuminating this pattern reconstructs the original light wave geometry so viewers can look around objects. Dennis Gabor won the Nobel Prize for elucidating holography in 1947, long before modern lasers made high-quality holograms widely feasible.
While pure holograms lack corporeal integrity and cannot be touched, the holodeck integrates replicator and transporter technology to temporarily materialize solid objects and characters that can be interacted with physically. Fictional characters like Cyrus Redblock, Felix Leach, and Professor Moriarty discovered they were trapped by solid holodeck matter until pattern buffers were deactivated.
10 Key Ideas
- High accelerations without protection would kill a spacecraft crew due to severe G-forces unless inertial dampers create an artificial gravitational field to cancel out reaction forces during acceleration.
- Because the speed of light is constant for all observers regardless of relative motion, space and time become relative and make light-speed travel for massive bodies impossible.
- Mathematician Kurt Gödel developed a solution to Einstein's equations involving a uniformly spinning universe where one could travel back in time by moving in a large circle in space.
- Mathematically consistent wormholes in general relativity are transitory and pinch off faster than a traveler can pass through them.
- Recreating human beings via matter streams forces a choice between physical transport and immense information storage.
- Stephen Hawking discovered in 1974 that black holes emit radiation due to quantum fluctuations because near a black hole's event horizon, one virtual particle can fall inward while the other escapes, contributing negative energy that decreases the black hole's mass.
- Andrei Sakharov proposed in the 1960s that dynamic asymmetry could be generated if three specific conditions were fulfilled in the laws of physics during the early universe.
- Nature endows empty space with a non-zero energy known as dark energy, which is three times more significant than all matter in galaxies combined, though it cannot be harnessed for spacecraft propulsion.
- Operating accelerators to produce antiprotons requires immense budgets for electricity, personnel, and infrastructure, resulting in millions of antiprotons per dollar but costing vastly more energy to create than is recovered through annihilation.
- The Heisenberg uncertainty principle states that certain pairs of physical observables, such as a particle's position and velocity, cannot both be known with absolute precision.