Frank J. Tipler

That's just one of 20 known hard steps.

I mean, it was John Barrow and Frank Tipler who published this, gee, back in 1986.

When they wrote their book, The Cosmological Anthropic Principle, they came up with 10 hard steps where they're arguing.

This seems to defy a naturalistic explanation.

They agreed.

They cited Frank Tipler's work on rotating cylinders and referenced Kerr metrics for rotating black holes.

They discussed the Everett Wheeler model of quantum mechanics and the many worlds interpretation.

Talked about this stuff as if it was settled science where they came from.

He described it as a stationary mass temporal displacement unit powered by two topspin dual positive singularities.

Those are miniature black holes contained and rotating.

It created what he called a standard offset Tipler Cinezoid.

It's a gravity field that bends spacetime enough to move through it.

Perhaps the simplest explanation to this conundrum is that we are alone.

It was Michael Hart in 1975 and Frank Tipler in 1980 who first introduced a version of what I'm calling the direct Fermi paradox.

Tipler even titled his paper, Extraterrestrial Intelligent Beings Do Not Exist, concluding this to be the sole explanation to this dilemma.

In it, he argued that intelligences such as our own will eventually develop a self-replicating universal constructor with intelligence comparable to the human level.

and that such a machine could colonize the galaxy in less than 300 million years with present-day rocket technology.

Tipler's ideas are particularly ominous in that he predicts that the transition is being held back by a deficiency in computer technology and not rocket technology.

I concede that Tipler's solution clearly naturally explains the Fermi Paradox, but I don't agree that it's the only explanation.

There is another possibility, one that actually dawned upon me during a recent vacation a few weeks back.

And of course, you can also tinker with the simulation sandbox I made.

Honestly, I'm still trying to process the implications of this cosmological Hart-Tipler conjecture, but I'll leave you with a few thoughts.

I think, intuitionally, we kind of get a feeling that something must be wrong here.

Like, how does this make sense? And I've certainly been searching for some way to undermine this argument.

Oh, I mean, you point out, um, that, um, there are lots of al- so the point is they're not, they're not communicating with us, they haven't come visit us, and there are a number of reasons why.

And you elaborate in the book for some of the reasons, um- Why, and in fact, I think that you point out, ah, ah, Hart and Tipler, Frank Tipler, who, who, ah, I've debated on, on other things.

Um, ah, ah, nevertheless, they argued that there were reasons why aliens, ah, would, if they existed, would not be, um, um, would not be communicating with us.

And I guess Jill Tarter, you point, su- summed up, ah, I'll read these.

It requires sophisticated engineering, certainly, but no exotic technology beyond what a moderately advanced civilization might plausibly develop.

In 1980, astrophysicist Frank Tipler applied this concept directly to the Fermi Paradox and produced an argument so sharp it has never been fully answered.

Imagine a civilisation that builds a single self-replicating probe, a robotic spacecraft capable of travelling to another star system, mining local asteroids and comets for raw materials, constructing two or more copies of itself, and launching those copies toward further star systems.

The probe does not need to carry living beings.

And yet, no such probe has ever been detected in our solar system.

No artefact, no signal, no sign that the galaxy's most obvious and efficient colonisation strategy was ever executed by anyone.

Tipler himself drew a stark conclusion from this.

He argued that the absence of self-replicating probes in our solar system was near proof that intelligent life did not exist anywhere else in the galaxy.

In practice, The expansion would not proceed as a perfect exponential because some target systems would lack suitable raw materials, some probes would fail and the expanding wavefront would eventually encounter diminishing returns as nearby systems were already visited.

Mathematical models published in the astrophysics literature, including a landmark analysis by physicist Frank Tipler in 1980, and subsequent refinements by researchers including Eric Jones, Robert Freitas, and others, estimate that a civilization using von Neumann probes, traveling at even a small fraction of light speed, could saturate the entire Milky Way galaxy within approximately 1 million to 100 million years.

The exact figure depends on assumptions about probe speed, replication time and the fraction of star systems that provide suitable resources.

100 million years.