The Physics of

Presentation for the American School In Japan

Astronomy, Physics and Futuristic Lit classes on 11/18/04

By: Mr. John O’Leary, member of AAPT and ASP

What is wrong?

• Can’t hear explosions in outer space• Light and sound/particle waves never travel

the same speed.• You can’t see photon beams cross the sky

What is right?•Spherical Drops of Blood at 0 gravity

Science Fiction

• If it is not all correct, that is ok

• Star Trek is about possibilities of the Universe….just like Physics!

• Provides a medium for people to connect with each other and science

• Stephen Hawking says “Expanding our minds-where our minds can go!”

Star Trek’s Stage

• The Andromeda Galaxy is similar to our Milky Way Galaxy: 100,000 light years across!

Chunky salsa

• 1g = acceleration at Earth’s surface= 9.8 m/s2

• When the captain says: “Engage” (the impulse drive)

• Accelerate to 150,000 km/sec (1/2 speed light)

• If accelerations are < 3g’s• then it takes 2.5 months to reach that speed.

Dealing with Newton’s

3 Laws of Motion

The lack of seatbelts…

• Inertial dampers: invented to overcome Newton’s Laws—shock absorbers.

• Theory: artificial gravitational field that pulls in the opposite direction to the reaction force?

• Reaction time: 60 milliseconds

Einstein created 2 Major Problems

• #1:Fast Clocks tick slow

• If you go very fast, your on board clock ticks very slowly compared to the clocks on other planets and ships

• Can you return home?

• If across the Galaxy: Should I shoot?

• Answer would arrive more than 100,000 years later.

Synchronicity

• Faster you go, the slower time appears to go relative to outside time

• At close to the speed of light, a journey to centre of galaxy in 10 years (to people on ship)

• But 25,000 years would pass for Earth• Synchronisation of clocks and calendars

across vast federation of civilisations• --> must use F-T-L travel

How much!?!• Problem #2: Energy needed• Impulse engines for slower than light travel• Nuclear fusion (hydrogen => helium)• 1% mass -> energy (come out at up to 1/8th speed of

light)• Accelerate Enterprise to 1/2 light speed => need 81

times its mass in Hydrogen fuel• 4 Billion kg of ship requires 320 Billion kg of fuel• Use matter-antimatter drive (2 x mass)• Ships can not go the speed of light, it takes >mass of the

Universe to accelerate 1 molecule to the speed of light.

It gets worse...

• That was acceleration, now you need to stop…

• Same factor of fuel (81x)

• So to accelerate to 1/2 light speed and then stop again would require 81x81 = 6561 times mass of ship

Super-duper-scooper

• Collect hydrogen as you fly along?• Average density = 1 molecule per cm3

• To collect 1 gram =>

need collection panels with

diameter of over 40 km• This would give you 1 hundred-

millionth of fuel needed

Federation Prime Directive

• Members of Starfleet will not interfere in the cultures of pre-warp civilizations in any way.

• Starfleet officers are required to understand that allowing cultures to develop on their own is an important right and therefore must make any sacrifice to protect cultures from contamination, even at the cost of their own lives.

Temporal Prime Directive

• The Temporal Prime Directive : policy of 29th century Starfleet (when time travel becomes much more accessible) to not directly interfere with history and thus alter the timeline. Unlike the Prime Directive, however, Starfleet time travelers are further charged with a duty to maintain the current timeline and prevent history from being altered.

Time Travel

• 22 episodes in first two series alone.

Killing your mother before you were born: Paradox

“Hello? Hellooooo?”

• Pure energy beings

• Travel at light speed => internal clocks infinitely fast compared to ours

• Impossible to interact

with

A singular wormhole

• Stable wormholes?

• Transitory and minute

Warp Drives

• Warp space-time itself• Expand space-time behind you and contract

space-time in front of you• Faster-than-light travel• No time dilation• No rocket fuel• Energy for a Warp Drive? 1000 x Mass of the Galaxy!

Nifty side effects

• Tractor beams

• Deflector shields

That was the good news

• Possible on microscopic scale

• Energy requirements make impulse engines seem trivial

• Mass of sun bends light by 1/1000 th of a degree.

• What strength of gravitational field to bend phaser beam by 90o?

Atoms or Bits?(aka “Shift ‘em or fry ‘em?”)

• One human = 1028 atoms• extract info -> recombine it to form person• “matter stream” -> atoms *are* sent• If only use info, what happens to original?

50kg -> 1000 kiloton hydrogen

bombs• So take the atoms as well?• (Create atomic matter stream)

My hard drive floweth over

• To store info in human body• 1 kilobyte data per atom(one page)• 1028 kilobytes of data• Storage -> retrieval• If on 10Gb HD’s

(10cm ea)• 1/3 to the center

of the Galaxy!• Take 2000 times

age of Universe

Virtual playgrounds

• Interact with holo-objects and characters• Illusion of 3D surrounding environment• Replicator technology for objects

Hyperspace

Searching for ET

• 400 billion stars in our Galaxy

• Most have planets

• Life may be everywhere

• Intelligent life may not be abundant

• Earth has only sent out radio signals for last 60 years

SETI

• SETI (Search for Extra-terrestrial Intelligence

• Has been searching for years

• Now searching billions of frequencies

• We are still waiting for a signal

References

• Permission to use some materials were granted by Seranne Howis at Rhodes University from her presentation to the Rhodes University Astronomy Society. http://rucus.ru.ac.za/~wolfman/Essays/Trek/trektalk.html

• Lecture notes were taken by Mr. O’Leary at Prof. Lawrence Krauss at his lecture: The Physics of Star Trek at the American Association of Physics Teachers in San Antonio, Texas in August of 1999.

• Further information was taken from: The Physics of Star Trek, book by Lawrence M. Krauss, 1995.