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yup here it is. Real scientists doing real science on the possibilities of ET.
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April 26th, 2014, 08:27 PM
Does the Rapid Appearance of Life on Earth Suggest that Life Is Common in the Un
yup here it is. Real scientists doing real science on the possibilities of ET.
I don't think anyone on this forum would debate the possibility of life on other planets. To think that it doesn't exist on one of the billions of worlds in one of the billions of galaxies in our known universe seems a little absurd.
But Reiku will say it means they must have visted us.
Actually, given 8 billion years evolution (this is about as much time allowed for life to appear before us) we are relatively new kids on the cosmic estate. To think aliens have no chance of getting here, or that they couldn't have in the 8 billion years we haven't been about, may turn out to be one of the most selfish mistakes of mankind. It might cost us in the future. A unprepared civilization is a race in danger.
As for rapid development, the Cambrian explosion comes to mind Cambrian explosion - Wikipedia, the free encyclopedia
This was the rapid development of simple into complex life.
Timeline of evolutionary history of life - Wikipedia, the free encyclopedia
Or rapid appearance of life... 4 billion years ago? More like a rapid evolution of life, with five mass extinctions. And it still found a way.
The anthropic principle guarantees our existence irrespective of how small the probability of our existence is. Therefore, it cannot be inferred from our existence that the probability of our existence is not extremely small. And because the anthropic principle does not extend to the existence of other life in the universe, the likelihood of other life existing in the universe in addition to our existence may be so small that we may indeed be alone in the observable universe. To argue that life is common in the universe is to argue that life is statistically easy to produce, but one cannot use life on earth as evidence that it is easy to produce.
Originally Posted by KJW
the Anthropic principle? Which one says this, there are about four versions, and I am not brushed up on them.
That is the problems with mathematicians, they confuse math theories with reality.
There might be other living things in the universe, and someday we might even find some evidence to support that hypothesis.
However until we do find some evidence and figure out how to make contact the question remains moot.
That is the problems with mathematicians, they confuse math theories with reality.
There might be other living things in the universe, and someday we might even find some evidence to support that hypothesis.
However until we do find some evidence and figure out how to make contact the question remains moot.
So cynical. I don't believe the question is moot. Where is the inspiration in humanity these days?
Surely these are exactly the sort of interesting questions physicists should be asking.
Why do you think the Drake equation matters to anything at this time?
Why do you think the Drake equation matters to anything at this time?
Well I don't know if it ''matters'' as such, but it is a statistical way to test civilizations. Statistics isn't the same thing as real life, but statistics may be a good indication to how much life we could be dealing up to.
I think the lowest estimate is anything from a thousand to a million civilizations in the milky way alone.
I actually pointed out some of those facts of Drakes equation in some other work...
Consider some figures to help you make your decision: There are roughly around 300 billion stars alone in this small portion of the universe we call our galaxy, the Milky way. There are in fact hundreds of billions of galaxies in this universe. Some say as large as 500 billion!
There is no viable way to know exactly how many stars are in the universe in total. We know the universe is massive possibly even infinite, it has a diameter of about 93 billion light years. A light year is how long it takes for a particle of light to travel in a year. Since a particle of light, like all massless radiation in the universe travels at the fastest speed known... in just one second, to give you an idea, light can travel 186,000 miles, it then has taken about 13 billion years for a photon to reach us from the farthest reaches of space... that is a lot of space and a lot of time.
In a universe, where so many galaxies reside in so much openness it is hard to imagine that Earth is the only planet that harbours life... Earth came onto the cosmic stage around 4.5 billion years ago, but we know star systems have been forming much earlier than this. The earliest galaxy discovered may have clumped together as early as 450 million years old. It was around 600 times more denser and 8.5 times smaller than our own. Star formation alone happened much earlier than this, it was at it's maximum rate of production about 5-8 million years after Big Bang.
With some idea how long we have for some life to appear in the universe, we can draw some conclusions from home. Life appeared on our planet about 3.6 billion years ago... Earth was less than 10 billion years old! Taking into account how long it probably took for Earth to produce just the right conditions, known as the primordial sea, in a time scale compared to the universe, life on Earth appeared rather dramatically and quickly. But just as dramatic, many of these lifeforms where destroyed in what is called a mass extinction. There are have been five estimated mass extinctions, which can be related to a number of different factors... but the main point is, that as soon as that original single celled life appeared on Earth, life in general has been relentless. Today, over 8 million species of life exist on planet Earth.
So we know life must want to thrive and as the famous statement from Jurassic Park says, ''life will find a way.''
So has it found a way on any other planet?
Most likely it has and most scientists would seem to agree that the universe is far too big to suggest that life elsewhere is improbable. In fact, life elsewhere should be expected, we certainly cannot be special enough to be the only organism ever to observe the universe.
Since galaxies where forming as early as 450 million years after big bang, that gives us about 8 billion years for the universe to allow life elsewhere, that would be, for an alien civilization an 8 billion evolutionary jump start. Now, I am not suggested that life appeared in the universe 8 billion years ago, but life may have appeared any time since then. Even a civilization only 1 billion years old would be like gods to us. Their technology will be far more advanced, they will have mastered interstellar space travel and they will know all sorts of new physics we are yet to discover.
Drake's equation, attempts to mathematically answer the question about how much life is in the universe. Probabilistically-speaking, given uncertainties as well, the equation can make an estimate of anything between 1000 and 100,000,000 civilizations in our galaxy alone. Keep in mind some figures I hit at you earlier, there being something around 500 billion galaxies in the universe alone. If all galaxies where roughly the same (which they are not, but for smudging purposes) this could mean there could be anything up to 500,000,000,000,000,000 civilizations in the universe! Even if we cut that number to half and by half again for good measure, it is still a large number!
How true this is, we will not know for a very long time. But it is safe to say, that if any of these large numbers are true, we must begin to be open to the idea that aliens may have in fact the technology to reach us from whatever distant star system they may be in. Today, some people think such thinking to be delusional that any alien civilization has ever visited our planet. After the little statistical lesson I have given, do you feel these sceptics are correct in what they say?
Thanks, I am quite aware of what the Drake equation is.
My question to you was, "Why do you think the Drake equation matters to anything at this time?"
Your first answer was, "Well I don't know if it ''matters'' as such, but it is a statistical way to test civilizations. Statistics isn't the same thing as real life, but statistics may be a good indication to how much life we could be dealing up to."
After looking at a few of your other threads I suspect you want to use the Drake equation to support your belief that UFOs are extraplanetary.
Whatever, I am not here to confront your belief in space aliens. I recognize that it would likely be a pointless exercise.
My comment was that the Drake equation doesn't matter and the question of whether aliens exist is not answerable unless something dramatically changes, like some actual evidence appearing.
Have fun looking for such evidence and try not to go full crank and conspiracy theorist over it.
(You should never go full crank.)
Why, did you want to meet your neighbors?
Thanks, I am quite aware of what the Drake equation is.
My question to you was, "Why do you think the Drake equation matters to anything at this time?"
Your first answer was, "Well I don't know if it ''matters'' as such, but it is a statistical way to test civilizations. Statistics isn't the same thing as real life, but statistics may be a good indication to how much life we could be dealing up to."
After looking at a few of your other threads I suspect you want to use the Drake equation to support your belief that UFOs are extraplanetary.
Whatever, I am not here to confront your belief in space aliens. I recognize that it would likely be a pointless exercise.
My comment was that the Drake equation doesn't matter and the question of whether aliens exist is not answerable unless something dramatically changes, like some actual evidence appearing.
Have fun looking for such evidence and try not to go full crank and conspiracy theorist over it.
(You should never go full crank.)
I don't think the Drake equation actually proves anything other than possibilities.
I think of alien life in much the same way. I ask in 8 billion years what are the possibilities some alien life could have become intelligent enough for intersteller travel. If we can gauge this on ourselves, then we appeared in only 15,000 years ago and our intellect is remarkable: That is 533,333,333 times smaller the amount of time other civilizations could have had. That's plenty time on the cosmic real estate.
Why, did you want to meet your neighbors?
Ohhh... You'll never get me in space. Even if the sun collapsed, if you think I am sitting on about 600 tonnes of fuel you can think again
I'd quite happily shoot myself before that. I wouldn't enjoy space, not for me.
I was using the term "anthropic principle" in a generic sense.the Anthropic principle? Which one says this, there are about four versions, and I am not brushed up on them.
I was using the term "anthropic principle" in a generic sense.the Anthropic principle? Which one says this, there are about four versions, and I am not brushed up on them.
ok.
I believe it's reasonable to expect there to be life elsewhere in the Universe.
Even if there as only an average of one life-viable planet per galaxy, there's still a LOT of galaxies out there.
As for why we've not detected anything, well, if we're the only life in our galaxy - how likely is it that'd we'd be able to detect life all the way over in another galaxy?
Also, we may be one of the very first lifeforms (or life-viable planets) to have developed in the Universe so far. We're still practically at the very first day of the Universe's lifespan, aren't we?
I agree altho' I would replace the word "Universe" with the phrase "our galaxy and the other galaxies". I also think there is a reasonable chance that primitive, or simple, life forms exist somewhere in the Solar System.
I'm sure I have read, here and in other sources, the argument that altho' life, and an advanced technological civilisation, exists on our planet this does not prove, or even provides real evidence, life exists elsewhere.
The situation, on the Earth, certainly does not offer conclusive proof about anything, but surely must be considered a major piece of evidence that life exists in other places.
I have to add I'm not certain this topic should be in the Physics sub forum.
Last edited by Halliday; April 27th, 2014 at 08:00 AM.
Why do you think life on another planet would have evolved along our path? Why do you assume they would be builders or travelers? What if they were highly intelligent, but immobile, plant-like lifeforms? Why can't the aliens simply remain as bacteria? How do you know in what way their environmental pressures will cause them to evolve?
To think that the aliens would have such immaculate evolutionary timing as to be roughly on our level of sentience, yet be capable of travelling thousands of light years, avoiding our detection equipment only to be spotted by some 14 year old on a camping trip is a pretty severe stretch. What if most life exists in the dark universe and we're the odd man out? Maybe we aren't detectable by the other life out there.
There are so many "what if" scenarios that settling on the little green men in a saucer one seems like bad judgment.
"Wibble"
Nobody seems to bother about the medium-ish height sort-of-purple ones.
Statistically, every Lottery winner should have lost.
Somethings I've always wondered about: We have successfully landed spacecraft on various celestial bodies within our solar system. Great efforts were taken to keep these machines clear of microbes and such but I can't help thinking nothing's perfect, so is it almost or is it truly a certainty that we have already sprinkled life on other planets? Could this life have survived and already be evolving on those worlds? If we are, as some people say, somewhere near the bottom of the intelligence scale when compared to the probability of other developed intelligences, then to what scale could the higher beings plant life elsewhere. Seems to me that if interstellar travel is in our future or may have already been successfully achieved then all it takes is for life to develop on only one planet amongst the trillions of existing planets in order for life to be distributed amongst the cosmos.
I get panspermia. I'm just playing devil's advocate. If one planet billions of years ago developed life and it got blasted into space to become sustainable chunks of frozen microbes then you might still only require one planet to develop all the life for the cosmos. Do I believe this, no.
*dirty laugh*
"sperm"
Now that is just childish.*dirty laugh*
"sperm"
(In other words I held off long enough for someone else to beat me to it).
I am more in favor of pseudo-panspermia, although I cannot state that panspermia is an unreasonable hypothesis,
as it is possible that life originated elsewhere in the universe and was ejected via impact-expelled rocks, so that it landed on several young planets (including Earth).
Ever heard of wormholes proposed by Einstein?Why, did you want to meet your neighbors?
Ohhh... You'll never get me in space. Even if the sun collapsed, if you think I am sitting on about 600 tonnes of fuel you can think again
Ever heard of wormholes proposed by Einstein?Why, did you want to meet your neighbors?
Ohhh... You'll never get me in space. Even if the sun collapsed, if you think I am sitting on about 600 tonnes of fuel you can think again
I have. Just like the Alcubiere drive, we need exotic matter for wormholes to keep them open long enough. We do actually have a negative pseudo-negative region of energy in the Casimir effect. Scientists are asking if we can somehow harvest it. No easy task.
I am more in favor of pseudo-panspermia, although I cannot state that panspermia is an unreasonable hypothesis,
as it is possible that life originated elsewhere in the universe and was ejected via impact-expelled rocks, so that it landed on several young planets (including Earth).
I am a big fan of Panspermia.
*dirty laugh*
"sperm"
Well, it's about fertilizing planets.
But factually there are lottery winners. Factually we have never met an alien race. (I know, what's a fact doing in a "cluelessone" thread?)
But factually there are lottery winners. Factually we have never met an alien race.
Statistically, the universe should be thriving. It might not be fact, but there isn't much fact you will win the lottery tomorrow, but someone is very likely to.
Just like someone is very likely to, in our history to visit us.
Citation needed.
Citation needed.
Michio Kaku
''It isn't a matter of if, it's a matter of when they visit us.''
or how of ten they visit us. lo lCitation needed.
Michio Kaku
''It isn't a matter of if, it's a matter of when they visit us.''
Again, appeal to authority. And it's not even someone who is considered particularly credible.Citation needed.
Michio Kaku
''It isn't a matter of if, it's a matter of when they visit us.''
Yes, you are a well rounded crank, Reiku.
I am more in favor of pseudo-panspermia, although I cannot state that panspermia is an unreasonable hypothesis,
as it is possible that life originated elsewhere in the universe and was ejected via impact-expelled rocks, so that it landed on several young planets (including Earth).
I am a big fan of Panspermia.
Last edited by Howard Roark; April 27th, 2014 at 06:02 PM.
My post was more meant to convey the fact that statistics can't prove anything.But factually there are lottery winners. Factually we have never met an alien race. (I know, what's a fact doing in a "cluelessone" thread?)
Even if there was a 99.999% chance of there being life on another planet - that doesn't mean there is.
Again, appeal to authority. And it's not even someone who is considered particularly credible.Citation needed.
Michio Kaku
''It isn't a matter of if, it's a matter of when they visit us.''
How about Hawking? He is already warning us of alien visitation. Is he credible enough for you>?
This is not what he said. He said something different (just as kooky as YOUR claims):Again, appeal to authority. And it's not even someone who is considered particularly credible.Citation needed.
Michio Kaku
''It isn't a matter of if, it's a matter of when they visit us.''
How about Hawking? He is already warning us of alien visitation. Is he credible enough for you>?
"Over the years, Hawking maintained his public profile with a series of attention-getting and often controversial statements:[261] he has asserted that computer viruses were a form of life,[262] that humans should use genetic engineering to avoid being outsmarted by computers,[263] and that aliens likely exist and contact with them should be avoided.[264][265]" (from wiki)
This is not what he said. He said something different (just as kooky as YOUR claims):Again, appeal to authority. And it's not even someone who is considered particularly credible.Citation needed.
Michio Kaku
''It isn't a matter of if, it's a matter of when they visit us.''
How about Hawking? He is already warning us of alien visitation. Is he credible enough for you>?
"Over the years, Hawking maintained his public profile with a series of attention-getting and often controversial statements:[261] he has asserted that computer viruses were a form of life,[262] that humans should use genetic engineering to avoid being outsmarted by computers,[263] and that aliens likely exist and contact with them should be avoided.[264][265]" (from wiki)
what are you talking about, you don't have the first clue what I am on about do you, yet again, trollisms!
BBC News - Stephen Hawking warns over making contact with aliens
Seriously, what has computer viruses got to do with alien visitation???
BOLD ENOUGH??
You didn't manage to read his post all the way through, did you.
Reiku,
You have problems with reading and comprehension.
In fact, his statement implies a total opposite of what you lot are saying.
And what does that have to do with computer viruses?
And what does that have to do with computer viruses?
Obviously he has no idea what Hawking is saying. Hawking likened alien visitation to a similar scenario when columbus reached the America's.
This clearly has fuck all to do with computer virus'. clearly, he had no context in which Hawking made his statement. Hawking clearly see's the possibilities of alien contact, whilst you lot, seem to think it is crank.
It's not, this is a wake-up call, not for this forum, but for our whole race.
Then why did you bring it up?
Why ask questions about computer viruses when they have "fuck all" to do with alien visitation?
Well, who says the aliens won't be in the form of a computer virus?
The notion that they have to be biological seems very egocentric.
Super-duper-mega-ultra advanced aliens could possibly take the form of Von Neumann probes.
i see von neumann probes as the most likely visitors we'll get. with really low values of "likely".
So now it seems like a good time to mention the Fermi paradox.
If space aliens are as common as the Drake equation suggests then where the effing hell are they hiding? We should be tripping over them all the time and be inundated with Von Neuman probes but so far nothing, nada, zilch.
Same thing with time travelers.
So now it seems like a good time to mention the Fermi paradox.
If space aliens are as common as the Drake equation suggests then where the effing hell are they hiding? We should be tripping over them all the time and be inundated with Von Neuman probes but so far nothing, nada, zilch.
One of the explanations could be that the majority of the extraterrestrial life forms have not yet reached the stage of multicellularity:
On endosymbiosis (link to an article by Ed Yong)
Except that isn't what the paper says. Never mind, interesting anyway.Life Should be Common in the Universe, physicists say
That is an excellent article.
Well then, you have not seen my neighbor yet. But his planet of origin may well be chemically induced--jus' sayin'.So now it seems like a good time to mention the Fermi paradox.
If space aliens are as common as the Drake equation suggests then where the effing hell are they hiding? We should be tripping over them all the time and be inundated with Von Neuman probes but so far nothing, nada, zilch.
Same thing with time travelers.
If, for what ever reasons, we can not exceed the speed of light, or create worm holes or whatever we as imaginative human beings can think up to travel through space in a timely manner, then we may never know of others out there. I think "life" is as inevitable as the universe is. Statistics say there are X amount of intelligent life inevitable. But if the laws can not be broken, our worlds may never cross. IF, the rules can be broken, we may never have the mental capacity to break those rules. IF, the number of intelligent beings that may be able to break rules are so few and far between that we may never know each other exist. Then we may be doomed to live out our species lives and never know they are out there. It may be the most cruel trick against intelligent life ever perpetrated.
We can guess, imagine, contemplate, extrapolate, formulate, and wish all we want, we may just never know. But it's not in human nature or possible not in intelligent nature to ignore the possibility. Just like all inventions, it starts with a dream.
Mark
There are 300 billion stars in our galaxy.
Even if we could travel faster than light, we might still never find the life out there.
Some answers I've heard relate civilization collapse to aggression, hedonism, or suggest that human level intelligence might be rarer than we think, because lots of life forms survive perfectly well without it. Pretty much all of them on earth.
But in answer to the Fermi paradox, a friend of mine suggested that perhaps few civilizations survive becoming dependent on fossil fuels. That may sound ridiculously anthropomorphic for a number of reasons, but fossil fuel does seem like low hanging fruit for any carbon based intelligent life form that started setting things on fire and developed mechanization. Does every civilization like us either run out of it, fail to discover a cheap alternative to sustain their large numbers and complex society, or over heat their planet long before they ever colonize space?
We've only been sending signals (radio) out for less than 90 years. If they are only 90 light years or more away or more then they are only just getting radio from us now. Or not at all if farther. Why would they come here if they had no idea we are here? It would be one hell of a mission to undertake for no reason. There may be billions of possible aliens out there, but the closest ones could be several trillions of miles away.
Mark
If aliens ever visit, it’ll probably be an archaeological expedition rather than social.
Is there any evidence that the emergence of life is unlikely? No matter how low the probability is per-roll-of-the-dice, if you roll more dice than that, you can always overcome it. How many die rolls were made in the first billion years of the Earth's existence?
It seems to me that any planet with the right conditions would make well more die rolls than were needed to win the game. All that is needed is for the game to be win-able.
The existence of extremophiles on Earth should tell us that exact conditions aren't necessary.
Extremophile - Wikipedia, the free encyclopedia
The main thing is for the planet in question to be at the right temperature, and preferably have elements in all three stages (liquid, solid, and gaseous), with a view toward the sky from its surface.
Life could start without a view of the sky, but it would eventually fizzle out if it didn't eventually migrate toward photosynthesis.
If they did visit us, they probably wouldn't go out of their way to make their presence known when they did.Citation needed.
Michio Kaku
''It isn't a matter of if, it's a matter of when they visit us.''
When human researchers venture into the rain forest to observe apes, or lions, or what-have-you, they take great pains to avoid interfering in the animals' natural behavior. It ruins their research if the animals start to react to them, because then they can't sort out what is natural and what is the result of interaction.
I think it's just really hard on humanity's ego to think that, from some other life form's perspective, we might just be interesting wild animals.
There's a great variety in stars, but also similarities derived from properties and similarities in the environment.
For example, someone suggested an intelligent immobile plant-like alien. Its possible, but rather unlikely, since it appears that intelligence is on earth is related or correlated to mobility(ability to act with respect to) and perception(ability to make decisions based on) of the environment.
Dolphins and Sharks are different but have some similarities in general shape because they have both evolved while using hydrodynamic mobility as an advantage, where as other organisms that might be highly venomous and feeding on immobile preys could be expected not to have an hydrodynamic shape. A rhino has poor eyesight it doesnt need it. If human ancestors were venomous armour plated monkeys with the ability to eat virtually anything like a goat imo we might never have developed higher intelligence and might have less accurate eyesight because survival would have been easy without intelligence and good eyesight. There might be exo life forms with different shapes from what we know but also others with similar shapes as marine life (prehistoric life forms, jelly-fish, fish, crustaceans. octopus, sea slugs etc)
We do not know what the odds are for life on other planets, we have no data so imo equations are a bit bull shite, what we do have is information about one sample, earth, and information about the properties of earth (water planet, molecular concentrations, etc) and it appears that the earth is not exotic, unique within our tiny perception sample, but I dont see why there would not be many liquid water planets with a moon, and that under similar environments, its reasonable to assume that a certain portion will have similar molecular interactions.
As for encountering alien life forms, lets hope it would not be something like the movies The Thing(the color remake and remake prequel)
etc...
Shortly after that photo was taken, the mother gorrila smashed David Attenborough's skull with a rock and they started eating him...
You had me going. I finally decided to look him up to confirm he is, in fact, not dead.
David Attenborough - Wikipedia, the free encyclopedia
So I see that some scientists do prefer to interact with the animals they are trying to film.
I wonder what aliens would gain by interacting with us humans?
There are probably laws about what alien visitors are allowed to do. If you go into the Amazon Jungle in Brazil where some tribes still exist that have had little or no contact with modern society - you can't just do whatever you want with/to them. You'd get in trouble if you terrorized them and the authorities found out about it. Why wouldn't space traveling aliens be part of nations also, and have to obey laws?
How about the Fermi Paradox? Where are they all? I would post a link to Wikipedia, but I cannot post links yet.
Max Tegmark says that he believes that we are the only life in the universe. No attempt at appeal to authority here, just a statement. Max also believes in the multiverse, so he definitely out on the edge in some areas.
>Where are they all?
Taking into account the exponential nature of evolution, the time-window two civilization may communicate with each other is getting smaller for more developed stages. For example, Infusoria is unlikely a life form human may want to get in contact ;o)
There are two key parameters:
1) The fact we see no visitors we may communicate
2) The percentage of stars a home for some ET civilization
If every star harbors at least one civilization and time they stay at level we may communicate with them lasts ~XXXXXX years (XXXXXX years from the moment they obtained the interstellar travel ) then having fact of no-communication we may asses the maximum XXXXXX to be consistent with fact of no-communication. Every second star assumption gives different XXXXXX and so on...
UFO observations may manifest the cases when contact has lost any sense (like Infusoria example)
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