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Beyond “Fermi’s Paradox” II: Questioning the Hart-Tipler Conjecture
universetoday.com ^ | Paul Patton

Posted on 04/10/2015 11:52:04 AM PDT by BenLurkin

The argument claiming that extraterrestrials don’t exist was actually proposed by the astronomer Michael Hart, in a paper he published in 1975. Hart supposed that if an extraterrestrial civilization arose in the galaxy it would develop interstellar travel and launch colonizing expeditions to nearby stars. These colonies would, in turn, launch their own starships spreading a wave of colonization across the galaxy.

How long would the wave take to cross the galaxy? Assuming that the starships traveled at one tenth the speed of light and that no time was lost in building new ships upon arriving at the destination, the wave, Hart surmised, could cross the galaxy in 650,000 years.

Even allowing for a modicum of time for each colony to establish itself before building more ships, the galaxy could be crossed in two million years, a miniscule interval on a cosmic or evolutionary timescale. Hart asserted that because extraterrestrials aren’t already here on Earth, none exist in our galaxy.

Hart’s argument was extended by cosmologist Frank Tipler in 1980. Tipler supposed that alien colonists would be assisted by self-reproducing robots. His conclusion was announced in the title of his paper ‘Extraterrestrial intelligent beings do not exist’.

Why is it important that Hart’s argument wasn’t really also formulated by the eminent Enrico Fermi? Because Fermi’s name lends a credibility to the argument that it might not deserve. Supporters of the search for extraterrestrial intelligence (SETI) want to search for evidence that alien civilizations exist by using radio telescopes to listen for radio messages that extraterrestrials may have transmitted into space. Interstellar signaling is vastly cheaper than a starship, and is feasible with technology we have today.

(Excerpt) Read more at universetoday.com ...


TOPICS: Science
KEYWORDS: enricofermi; fermiparadox; fermisparadox; franktipler; harttiplerconjecture; michaelhart; xplanets
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To: BenLurkin

In other words, because extraterrestrials don’t conform to his equation, they don’t exist. Scientific arrogance.


41 posted on 04/10/2015 2:25:04 PM PDT by I want the USA back (Media: completely irresponsible. Complicit in the destruction of this country.)
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To: BenLurkin

It is not possible to do faster than light speed, no matter what the equations say. Equations that don’t describe reality are wrong. Reality is not obligated to follow the equations.


42 posted on 04/10/2015 2:28:34 PM PDT by I want the USA back (Media: completely irresponsible. Complicit in the destruction of this country.)
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To: attiladhun2

Actually there is. When we mature enough - presuming we will - to understand the genius of our founders and the foolish tyranny of the left we will finally be rid of the elitists who are convinced they can control everyone else. This will lead, inexorably, to and end of warfare and an age of strong independence for the world’s citizens. Once we have thrown off tyranny as a legitimate style of governing we will be able to survive for the long haul.


43 posted on 04/10/2015 3:00:47 PM PDT by Louis Foxwell (This is a wake up call. Join the Sultan Knish ping list.)
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To: BenLurkin

Maybe we live in a bad neighborhood. I moved to a crappy part of town when I was 25. I couldn’t get ANYONE to visit.


44 posted on 04/10/2015 4:41:10 PM PDT by Vermont Lt (When you are inclined to to buy storage boxes, but contractor bags instead.)
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To: onedoug

You start by going downhill, with two guys pushing. Then you pop the clutch. Light speed is just over the next hill.


45 posted on 04/10/2015 4:46:22 PM PDT by Vermont Lt (When you are inclined to to buy storage boxes, but contractor bags instead.)
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To: FredZarguna

How did that Duell myth get such legs?


46 posted on 04/10/2015 5:10:58 PM PDT by 1010RD (First, Do No Harm)
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To: BenLurkin

We dont know the answers because we can’t imagine the questions


47 posted on 04/10/2015 5:22:10 PM PDT by muir_redwoods ("He is a very shallow critic who cannot see an eternal rebel in the heart of a conservative." G.K .C)
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To: rbg81

It’s been noted that animals that evolve fastest are the most parasitized and isolated from each other. However, horseshoe crabs do have at least some parasites.

Jellyfish, another ancient organism, may have a trick up its sleeve, for at least one jellyfish, called the “immortal jellyfish”, after reproduction reverts to its juvenile form, so does not die of old age.

http://en.wikipedia.org/wiki/Turritopsis_dohrnii


48 posted on 04/10/2015 5:47:27 PM PDT by yefragetuwrabrumuy ("Don't compare me to the almighty, compare me to the alternative." -Obama, 09-24-11)
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To: Mr. K

These people are infuriating and have been saying “no” since the beginning of humankind.


49 posted on 04/10/2015 6:06:58 PM PDT by SgtHooper (Anyone who remembers the 60's, wasn't there!)
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To: BenLurkin
Me and the taxidermist are eager to meet one.

Reminds me of the source of the name of that beautiful valley, Yosemite.

It comes from a phonetic repetition of the phrase the natives outside of the valley used about the natives inside the valley: "they are killers."

50 posted on 04/10/2015 6:40:08 PM PDT by Talisker (One who commands, must obey.)
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To: Talisker

Hooah!


51 posted on 04/10/2015 6:44:24 PM PDT by BenLurkin (The above is not a statement of fact. It is either satire or opinion. Or both.)
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To: BenLurkin

LOL, barbarian!


52 posted on 04/10/2015 6:48:09 PM PDT by Talisker (One who commands, must obey.)
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To: Mr. K

What evidence? I’d really like to know.


53 posted on 04/10/2015 7:29:33 PM PDT by onedoug
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To: 1010RD

Probably because it seems like a just comeuppance for some know-it-all; the irony of it, and all that.


54 posted on 04/10/2015 9:22:00 PM PDT by FredZarguna (It looks just like a Telefunken U-47 -- with leather.)
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To: Pontiac
Actually it would take much longer because you can not travel through the center of the galaxy.

Why not?

55 posted on 04/10/2015 9:36:33 PM PDT by FredZarguna (It looks just like a Telefunken U-47 -- with leather.)
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To: FredZarguna

Superluminal travel IS impossible, thats why you have to distort space/time to make the distance shorter.

The sun has proven this is possible by bending light showing starts that are BEHIND it, during an eclipse

You must not have been much of a physicist with such a closed mind


56 posted on 04/10/2015 10:06:49 PM PDT by Mr. K (I)
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To: Mr. K
Light passing near the sun bends, but it doesn't move any faster. Light falling into a Black Hole doesn't fall any faster.

I am so closed minded I believe that the Earth is round, and people who claim it's flat are wrong.

No [employed] physicist spends his time entertaining ideas that have been demonstrated in literally thousands of experiments to be impossible.

Wormholes are pure speculation. If they exist, you've got no chance of using them for transportation anywhere, because a) it's unlikely you could survive the trip and even if you could b) they only come out between fixed locations in spacetime.

57 posted on 04/10/2015 10:57:42 PM PDT by FredZarguna (It looks just like a Telefunken U-47 -- with leather.)
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To: FredZarguna
Radiation

The density of the star population produces so much radiation that the trip would be fatal.

58 posted on 04/11/2015 4:48:20 AM PDT by Pontiac (The welfare state must fail because it is contrary to human nature and diminishes the human spirit.)
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To: Pontiac
In which case, those regions could not be populated, so they'd be avoided anyway; which actually shortens the saturation time.
59 posted on 04/11/2015 8:44:21 AM PDT by FredZarguna (It looks just like a Telefunken U-47 -- with leather.)
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To: Louis Foxwell

Ain’t going to happen. The natural state of things is tyranny, not freedom.


60 posted on 04/11/2015 2:11:05 PM PDT by attiladhun2 (The Free World has a new leader--his name is Benjamin Netanyahu)
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