Knocked-Up Cnidaria, Expectant Echinodermata

This must be Thursday. I never could get the hang of Thursdays.
— Arthur Dent (Douglas Adams, The Hitchhiker’s Guide to the Galaxy)

Last Thursday, my wife gave birth to our second child. Nine months of prenatal vitamins, heartburn, lower back pain, kicking, and sleepless nights culminated in the delivery of a beautiful baby girl.

However, the process of delivery leaves much to be desired. For those who have never experienced mammalian reproduction, allow me to summarize it thus. (Warning: no storks, buns, birds, or bees are involved.)

Continue reading “Knocked-Up Cnidaria, Expectant Echinodermata”


Faster than Slower than Light

In the last article on Tachyon Rocketry, it appears that even a rocket propelled by tachyons is limited by the lightspeed barrier.

The problem is that our bodies (and our starship) are made of electrons, quarks, and other particles with real, non-zero mass. In the context of faster-than-light tachyons, such particles are known as bradyons or tardyons, and are always constrained to travel slower than light.

What if we got rid of the starship altogether? Instead of traveling the galaxy the slow way, what if we could just transmit ourselves to our destination? Sort of like Star Trek’s transporter technology?

Continue reading “Faster than Slower than Light”

Tachyon Rocketry

In my last article, I fiddled with an interstellar spaceship propelled by a photon rocket. The maximum speed (more correctly, delta-v) of a rocket depends on the exhaust velocity of its propellant. Since we know of nothing that travels faster than light, photons seem to be the best possible propellant.

But what if our propellant traveled faster than light? Particles that travel faster than light are generally called tachyons, and if they exist, they have some very strange and inconvenient properties. (In fact, FTL Pizza recently closed its Tachyonic Anti-Telephone Booth because kids kept making prank calls to Albert Einstein.)

As the saying goes, “relativity, causality, and FTL: pick any two”…
Continue reading “Tachyon Rocketry”

Photon Rockets for Interstellar Travel

Say you want to build an interstellar rocket. Cool beans. What’s the best way to go about it? Well, to get the highest possible delta-v, you want the highest possible exhaust velocity for your rocket propellant.

So what’s the fastest thing in the universe? Unless you’re living in a universe with FTL, that would be light, which travels at about 300,000,000 meters per second. We’ll use a jet of photons (otherwise known as a beam of light) to propel our starship.

The problem? Photons are the fastest things in the universe, but the thrust-to-power ratio of a photon rocket is pretty low. How low? In the words of the Atomic Rocket engine list, “three hundred freaking megawatts” for every Newton of force.

In other words, the maximum output of a typical nuclear power plant would (given a 100% efficient photon rocket) just barely be able to levitate a measly paper clip against Earth’s gravity.

Well darn.
Continue reading “Photon Rockets for Interstellar Travel”