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 ...
you’re sure of that?
any other scientific theories you can prove impossible for us?
should we close the patent office?
You must be lots of fun at the office Christmas party.
;^)
5.56mm
True, humans can’t even get the present straight. With lefties at the helm of world-civilization, I definitely see no hope. They rob from the future, exacerbate tribal tensions, and think equity includes allowing gangster regimes access to nukes and ICBMs. There is no reason to suppose a future of hyper-drive spaceships and terra-formed planets.
Evidently, you are of the opinion that there are time-travelers. I ask the same question of you that Fermi asked, mutatis mutandis:
"If there are time-travelers, where are they?"
Oh yes, they absolutely should say hello.
Me and the taxidermist are eager to meet one.
f intelligent species only last 100,000 years on average, they are biological “flashes in the pan”. But if they are as durable as horseshoe crabs or coelacanth fish, at 450 and 400 million years.
People literally don’t want to hear it. I think they instinctively sense there is more truth in my view of the future than Gene Roddenberry’s.
First, your use of that statement betrays that you don't know what you're talking about. Charles Holland Duell, the head of the patent office who supposedly said this, never made such a statement. In fact, he said EXACTLY THE OPPOSITE: "In my opinion, all previous advances in the various lines of invention will appear totally insignificant when compared with those which the present century will witness. I almost wish that I might live my life over again to see the wonders which are at the threshold."
Second, neither Duell nor the various others to whom this claim is attributed are/were physicists. At one time, long ago, I was one.
Third, what I would urge you to "close" is your office at the Flat Earth Society, because we have roughly as much evidence that superluminal travel is impossible as we have the the Earth is round.
If Liberals win out, we will slowly devolve back to the primordial ooze.
They have won out and we are “devolving” back to tribalism.
They may not any smarter than us. We ourselves may only be one lucky technological break away from interstellar travel. Who knows?
And suppose there is a superior intellect — it could very well be more like the gap between us and chimps, than us and ants.
It's never been done before so there is no way to know if it's even possible.
Actually it would take much longer because you can not travel through the center of the galaxy.
That means that star travelers will have to travel along the rim to reach us.
Maybe. Or maybe we are their intellectual ants. For every Einstein, Shakespeare, or JohnPaul2 — we have thousands of islamonazis and obama voters. The numbers aren’t favorable.
Taking E=mc² as a staring point, could you please elucidate that statement?
I predict that you and I will go the rest of our lives and never see an alien. Will never hear any authority announce that there is (intelligent) alien life. Will continue to be entertained by whispers, rumor, fantasies and thoerization on the possibility of aliens.
Not to say there aren’t any — just not here.
please...
E=mc^2 has nothing to do with GENERAL relativity, which is the theory on which wormholes are based. In order to travel the distances of space you cannot go there without distorting the gravity field and moving space closer to you.
There is enough evidence to suggest there have been visitors to this planet before, so that means there must be ways to accomplish space travel.
Yes. Exactly. They’re almost certainly out there but have no reason to come to such a primitive place as here. Indeed they’ve probably quarantined earth as a source of dangerous primitivism- infection to them
Havent you seen what’s Occupying our White House recently?
If you don’t believe in the existence of hostile extra- terrestrial alien invaders from outer space - then how do you explain the current Occupier of our American White House? (He hides his Certificate of Live Hatching because it’s written in Ferengi )
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.