ALL SCI-FI

[Gord Green]

https://www.forbes.com/sites/startswithabang/2018/04/05/the-drake-equation-is-broken-heres-how-to-fix-it/

This is a rather long article, but I found the concepts discussed fascinating!

The Drake Equation Is Broken; Here's How To Fix It

From FORBES: by Ethan Siegel

In 1961, scientist Frank Drake wrote down a simple-looking equation for estimating the number of active, technologically-advanced, communicating civilizations in the Milky Way. From first principles, there was no good way to simply estimate a number, but Drake had the brilliant idea of writing down a large number of parameters that could be estimated, which you would then multiply together. If your numbers were accurate, you'd arrive at an accurate figure for the number of technologically advanced civilizations that humanity could communicate with, within our own galaxy, at any given moment.

It's a brilliant idea in concept, but one that's become less and less useful as we've learned more about our Universe. As it stands today, the Drake equation is broken, but we know enough about the Universe to construct an even better framework.

The possibilities of having another inhabited world in our Milky Way are incredible and tantalizing, but if we want to know whether it's real or not, we absolutely have to get the science right.

The Drake equation, to be specific, said that the number of civilizations (N) we have at any given time within our galaxy, is equal to the product of seven different unknown quantities from astronomy, geology, biology, and anthropology, each of which build off of the previous element. They are:

1. R∗, the average rate of star formation,

2. fp, the fraction of stars with planets,

3. ne the average number stars-with-planets that have one that could support life,

4. fl, the fraction of those planets that developed life,

5. fi, the fraction of life-bearing planets that developed intelligent life,

6. fc, the fraction of these intelligence-having planets that are technologically communicative across interstellar space, and

7. L, the length of time such a civilization can broadcast-or-listen.

Multiply these numbers all together, in theory, and that will give you the number of technologically advanced, broadcasting civilizations we have in the Milky Way today.
But we might not have to find another Earth-like world to find life; our own solar system may have all the ingredients we need. We simply don't know how ubiquitous life is.

Only, there are huge problems with this setup. There are a number of unspoken assumptions that simply writing down the equation this way makes, that simply don't reflect reality.

Problems for its modern-day usefulness include:

⦁ The fact that the equation was written before the Big Bang was validated and the Steady State model was disfavored.

⦁ The equation assumes that only one planet per star system could support life.

⦁ That intelligent, technologically advanced life will never spread to other worlds.

⦁ And that broadcasting-and-listening-for radio signals is the method by which an intelligent species would choose to communicate across interstellar space.

That last assumption, in particular, was the motivation for SETI — the search for extraterrestrial intelligence (with radio dishes) — which has, of course, come up empty.
The Atacama Large Millimeter submillimeter Array (ALMA) are some of the most powerful radio telescopes on Earth. They are only one small part of the array forming the Event Horizon Telescopen and can image the Magellanic Clouds ) and all of the stars in the southern sky, unlike most northern hemisphere observers.

This doesn't mean, however, that there aren't other worlds out there with intelligent life on them! Despite our uncertainties about what's out there or whether/how they might attempt to search for or contact us, the possibility of intelligent, communicative, or spacefaring extraterrestrials is one of tremendous interest to not only scientists, but all of humanity.

Many of the steps of the Drake equation may be problematic, and they contain the major issue that there are huge uncertainties associated with them: so large that they render any conclusion about N, the number of civilizations within our galaxy, meaningless. But it's 2018 now, and there are a huge number of things we know about our galaxy and our Universe that we didn't know in 1961. Here's a better approach.

By surveying star clusters and field stars in and out of our galaxy, as well as measuring the extent of the Milky Way, we can simply determine the number and types of stars that exist.

1.) Ns: the number of stars in our galaxy. Why estimate the rate of star formation when we can simply look at the number of stars we have today?

We know how large our galaxy is, how thick it is, how large the central bulge is, and what their mass distribution is. Based on what we can observe with extremely powerful all-sky and pencil-beam (where you look at one narrow region very deeply) surveys, we can simply state that there are between 200 and 400 billion stars in our galaxy. An uncertainty that's only a factor of 2 is pretty good, and tells us that we have a very optimistic starting point: each star has a chance for success.

Let's pick the larger number here.
Kepler has found thousands of planets around stars in the Milky Way, teaching us about the mass, radius, and distribution of worlds beyond our Solar System.

2.) fp: the fraction of stars with planets. This is one we can keep from the original Drake equation, but in the aftermath of Kepler, it isn't all that interesting. Why? Because it's close to 100%! The fraction of stars with planets around them, based on the number of stars we've surveyed and what we've learned about them, is somewhere in the ballpark of at least 80%. To say "the fraction of stars with planets" is 1 is a nice, easy victory for the optimists out there.

Earth, around our Sun, has the right conditions for life. But what about other stars?

3.) fH: the fraction of stars with the right conditions for habitability. This gets more interesting now! Of the major classes of stars, how many of them have worlds that could support life?
A star like our Sun — with our Sun's mass, radius, and lifetime — could do it, as evidenced by our existence. But what about a more massive star? At some point, they'll be massive enough to burn through their fuel too quickly, and intelligent life could never arise.

On the other end, a low-mass star may be too unstable, flaring and blowing off a planet's atmosphere, or with little enough ultraviolet light that life cannot arise. We might worry about if there are enough heavy elements to support life on a world, or if a certain location in the galaxy renders the environment too chaotic for life. These may be unknowns, but we can probably safely say that at least a quarter, or 25%, of stars in our galaxy can have a potentially habitable planet.

4.) np: the number of worlds around habitable stars with the right conditions for life. This is something we've learned a tremendous amount about from our exoplanet studies, but tremendous questions remain. What makes a world habitable? In the early solar system, Venus, Earth, and Mars all had similar conditions. In the outer Solar System, worlds like Enceladus and Europa, with sub-surface oceans, may have underwater life. In systems with gas giants at Earth-like locations, large moons could see life arise on them. Although the uncertainties are very large here, I think it's a fair estimate to say that of the stars which can have a potentially habitable world, on average there will be one world that clearly has the best chance for life. That's the world we're interested in, and so we'll say np = 1.

At this point, by the way, we can multiply those first four numbers together to get an estimate for the number of worlds with good chances at life within our galaxy: 100 billion.

That's a promising start.

5.) fl: the fraction of these worlds where life arises. This is a great time to line up with Drake again, because this is one of the great unknown questions in the search for life beyond Earth.
Of all the potentially habitable worlds, how many of them take that first incredible step, where life arises from non-life? Or, if primitive life originates in interstellar space, how many worlds see life take hold on the surface, in the oceans, or in the atmosphere? We don't even know the answer for our own Solar System, where it's arguable that we may have as many as 8 other worlds where life arose at some point.
Life may be common; optimistically, it may have a 10% chance of arising from non-life.
Or, alternatively, it could be exceedingly rare: a one-in-a-million shot or worse.

Signatures of organic, life-giving molecules are found all over the cosmos, including in the largest, nearby star-forming region: the Orion Nebula. Someday soon, we may be able to look for biosignatures in the atmospheres of Earth-sized worlds around other stars.

The uncertainties here are huge, and any number that you can pick is as ill-motivated as any other. Someday in the future, we'll have the capability of performing our first tests, however.
When our telescope technology enables us to determine the atmospheric contents of worlds, we can look for the presence or absence of biosignatures like methane, molecular oxygen, and carbon dioxide. It will be indirect evidence, but it should be an incredible step towards inferring whether worlds have life on them or not.

If we say there's a 1-in-10,000 chance that a potentially habitable world has life on it, as good a guess as any, that means there are 10 million worlds in the Milky Way where life exists.

6.) fx: the fraction of life-having worlds with complex, differentiated organisms. Defining life as "intelligent" or not is a hazy prospect at best, as even the top scientists still argue over the classification of dolphins, great apes, octopi, and many other organisms as intelligent or not. What no one will argue about, however, is whether an organism is complex and differentiated: with different body parts with different functions and structures, in a macroscopic, multicellular arrangement.

It took billions of years of life thriving on Earth until we evolved the first multicellular organism, and then hundreds of millions of years more until we developed gender in reproduction; without both, out-competing single-celled life would be impossible, as they'd out-evolve the larger forms of life.

A bonobo 'fishing' for termites is an example of a complex, differentiated organism that uses primitive tools. It may not count as a scientifically/technologically advanced species, but it certainly counts as multicellular, differentiated, and highly interesting from an astrobiological perspective.

Again, Earth is our only laboratory for this, but let's be optimistic in the absence of evidence, and assume there's a 1-in-1,000 chance that a world that starts with a primitive, replicating, information-encoding strand of life can lead to something like the Cambrian explosion.

That gives us 10,000 worlds in the Milky Way teeming with diverse, multicellular, highly differentiated forms of life. Given the distance between the stars, that means there's likely another planet where this has occurred just a few hundred light years away.

7.) ft: the fraction of those worlds which presently house a scientifically/technologically advanced civilization. This is a superior question to the ones asked by the Drake equation. Who cares if this is the first or the tenth time a technologically advanced civilization arose?
Who cares if they're using radio waves? Who cares if they blow themselves up or self-extinct, or whether they have spacefaring ambitions or not? The big question is whether there are extraterrestrials who are intelligent the way we're intelligent, and that means scientifically and technologically advanced.

The 'holy cow' mosaic of the Mars Phoenix mission, with revealed water-ice clearly visible underneath the lander's legs. In order to learn the maximum amount possible about the presence or absence of life on a world, you absolutely must touch down and look, explicitly, for the surefire signatures.

There's no evidence for this anywhere other than Earth, of course, which means there's a huge range of possibilities. It could be easy, like 1% of them get there, or it could be a freak coincidence that humanity arose at all, and the odds could be more like one-in-a-billion.
Here on Earth, it's been about 500,000,000 years since the Cambrian explosion, and we've only had a technologically advanced species on the planet for less than 1,000 years. Assuming humanity lasts for a few thousand more in this state, that means that Earth will have spent 1-in-100,000 of our time with complex, differentiated organisms in a technologically advanced state.

Even with 10,000 such worlds in the Milky Way, there's only approximately a 10% chance, under these estimates, that another scientifically/technologically advanced civilization exists at the same time as us.

Once intelligence, tool use and curiosity combine in a single species, perhaps interstellar ambitions become inevitable.
But with all that said, it's those last three numbers — fl, fx, and ft — that have such large uncertainties that make accurate estimates an impossibility right now.

Knowing how many worlds there are out there in the Milky Way with life on them, and finding even one, would have tremendous implications for our existence, and for understanding our place in the Universe. Taking even the next step, and learning that there were complex, differentiated, large organisms on a world, like we have with the fungal, animal, and plant kingdoms on Earth, would revolutionize what's possible. And finally, the chance we'd have to have communication, visitation, and a knowledge exchange with a scientifically or technologically advanced alien species would forever alter the course of humanity.
It's all possible, but there's so much more we need to know if we ever want to find out. We must take these steps; the rewards are too great if there's even a chance of learning these answers.

Astrophysicist and author Ethan Siegel is the founder and primary writer of Starts With A Bang! His books, Treknology and Beyond The Galaxy, are available wherever books are sold.
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There comes a time, thief, when gold loses its lustre, and the gems cease to sparkle, and the throne room becomes a prison; and all that is left is a father's love for his child.

[Custer]

[Gord Green]

Just consider the fact that we've only had electric lights, automobiles, telephones and airplanes for a little over 100 years.

We've only had radio and television for about 100 years and we've still just stuck our toe in the shallow end of space.

Heck, WE"RE the infant civilization!
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There comes a time, thief, when gold loses its lustre, and the gems cease to sparkle, and the throne room becomes a prison; and all that is left is a father's love for his child.

[Custer]

Indeed... I think it has been said that, if humans began on January 1st, then, if it's now 11:59 pm on December 31st, then Julius Caesar was killed at, um, supper time on New Year's Eve?

[Gord Green]

[Gord Green]

Fermi's paradox asks why, if the universe is full of planets and at least some could host technologically advanced civilization, there are no signs of aliens to be found.

One possible and pessimistic solution to Fermi's paradox proposes that such civilizations are too short-lived to make contact with each other.

Maybe a civilization self-destructs or quickly exhausts the resources of the planet and degrades the environment. So a quick rise is followed by a sudden collapse.

There is also a more optimistic solution, when a civilization finds a more sustainable way of living. Limiting its consumption a civilization will reduce its impact on the planet. It will also limit the energy waste and output.

Doing so, may a civilization becomes harder to detect from beyond its planetary boundaries, but it will ensure its longevity and not only as traces in the geological record.

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There comes a time, thief, when gold loses its lustre, and the gems cease to sparkle, and the throne room becomes a prison; and all that is left is a father's love for his child.

[Robert (Butch) Day]

The entire Drake Equation is a fraud! It is based upon assumptions with NO supporting data!
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Common Sense ISN'T Common

[Gord Green]

Humans alone in universe, depressing study finds

http://www.foxnews.com/science/2018/06/25/depressing-study-suggests-humans-are-alone-in-universe.html

E.T. has not yet phoned home because he may not be smart enough to know how to do it. Or simply put, he may not exist at all.

A new study from the Future of Humanity Institute (FHI) at Oxford University, aptly named "Dissolving the Fermi Paradox," suggests that humanity is alone in the observable universe, putting a damper on the theory that there is intelligent life somewhere in the known universe.

"When the model is recast to represent realistic distributions of uncertainty, we find a substantial ex ante probability of there being no other intelligent life in our observable universe, and thus that there should be little surprise when we fail to detect any signs of it," the study's abstract reads.

"This result dissolves the Fermi paradox, and in doing so removes any need to invoke speculative mechanisms by which civilizations would inevitably fail to have observable effects upon the universe."

The Fermi paradox, named after physicist Enrico Fermi, is the contradiction between the lack of any evidence that Earth has been visited by intelligent extraterrestrial civilizations and the high probability that one or multiple civilizations exist, due to a number of factors.

The factors include: there are billions of stars in the galaxy similar to our Sun; many of these stars have Earth-like planets; and some of these civilizations may have developed interstellar travel, something that is being discussed now by experts, including theoretical physicist Dr. Michio Kaku.

The study, which was published earlier this month, was conducted by Anders Sandberg, Eric Drexler and Toby Ord.

Sandberg, Drexler and Ord also look at the famous Drake Equation, a seven-term equation that attempts to look at the differing variables that would be relevant for intelligent lifeforms. This includes factors such as formed stars and their planets, the average number of planets that can potentially support life. Other factors inclue a fraction of those planets that can develop life and a fraction of these civilizations that have become intelligent.

In this study, Sandberg, Drexler and Ord reconsidered the Drake Equation, looking at adding chemical and genetic transitions to it.

They noted that by incorporating these into the equation, it brings up significant amounts of scientific uncertainties.
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There comes a time, thief, when gold loses its lustre, and the gems cease to sparkle, and the throne room becomes a prison; and all that is left is a father's love for his child.

[Gord Green]

A follow-up to the above article :

http://thefederalist.com/2018/08/17/study-humans-almost-surely-sentient-life-universe/

There are 19,000,000,000,000,000,000,000 Earth-like planets in the observable universe. Out of all 19 sextillion of these, Earth is likely to be the only one with sentient life.

August 17, 2018
By Jonah Gottschalk


I’ve got some tough news for those of you toting around a towel, hoping to be whisked off as a hitchhiker around the galaxy: We’re probably alone. And I don’t mean there’s no other intelligent life near us. I don’t even mean there might not be any other life in the galaxy. I’m talking about the entire universe.

About a month ago, three of the world’s most esteemed scientists and thinkers, Eric Drexler, Dr. Anders Sandberg, and Toby Ord (I put the Oxford comma here only out of respect for them), released a fascinating study about the Fermi Paradox.

For those of you who don’t frequent astrophysicist circles, the Fermi Paradox is the contradiction between our current scientific knowledge of life, which holds that life should be relatively common in the universe, and the fact that there seems to be no evidence for extraterrestrial life, despite our best attempts at contact.

The study in question takes a harsh reevaluation of the paradox, finally coming to the conclusion that life, if it exists elsewhere at all, isn’t nearly as common or likely as we used to think. Their final estimate holds that there is a 53 percent to 96 percent chance that we are alone in the galaxy, and a 39 percent to 85 percent chance that we are alone in the entire observable universe.

So, long story short, there are 19,000,000,000,000,000,000,000 Earth-like planets in the observable universe. Now it seems that, out of all 19 sextillion of these, Earth could be the only one with sentient life.

If you want to take a deep breath now, or maybe grab a drink, I don’t blame you. That’s a lot of space. And it looks like it’s all ours to handle, a responsibility of almost incomprehensible proportions.

But, in a way, this isn’t the first time this has happened. There have been many times in history that our vision has been expanded larger than ever before. And to understand why we have to look back to a single verse, from a story that has been with us since the beginning of human civilization.

Ancient Knowledge for Modern Problems

Most Christians I’ve met have one of two opinions about Genesis 1. It is either the exact way the universe was created 6,000 years ago, in seven days, (may the Inquisition take those heretics who doubt it!) or it is an old Israeli story of minimal importance compared to the main event in the New Testament.

Young Earth Creationism, while wrong in my opinion, is essentially harmless. Who are we to tell people how to read into the Bible? But simply glossing over the opening act of the Bible, as I did until recently, will cause you to miss out on of the most important passages in the entire Bible: Genesis 1, verse 26. “Then God said, ‘Let Us make man in Our image, after Our likeness, to rule over the fish of the sea and the birds of the air and the livestock, and over all the earth itself and every of creature that crawls upon it.'”

The meaning of this is key to our existence; We, as humans, are made unique among the creations of the world, with the task of overseeing the earth. But what does God mean by the earth? The world used to, in the eyes of the ancient Hebrews, be a much smaller place, containing just the Near East.

Over time, of course, this expanded, to include the rest of Asia, Africa, and Europe, and later the Americas and the rest of the world. As you can see, humanity has been in a continual process of realizing that we were given control over much more than we ever previously guessed. Now, as we know the galaxy is full of trillions of uninhabited earth-like planets, we must understand what this passage really means.

To look at it from a semantic perspective, the Hebrew word we always translated to earth, “‘erets,” really means more “land” or “creation.” This means we have to, once more, expand what we thought we knew of creation, and by extension, what our gift from God contains.

Science and our species’ experience has shown us that we could very well be the lone thinking species out there. Now we must ask why we are alone and what does it mean. For Christians, the answer has been sitting there under our noses the whole time.

The universe is a gift, and if there is one thing we can all agree on it’s that we should make the most of what has been given to us. Humans are meant to be caretakers of life in the universe, and as terrifying and awe inspiring as that duty is, it is vital that we remember this as we go about our life.

As citizens of the nation that leads the free world, it is our duty to ensure that humans, and by extension, life, goes on.



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There comes a time, thief, when gold loses its lustre, and the gems cease to sparkle, and the throne room becomes a prison; and all that is left is a father's love for his child.