ET call home

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Re: ET call home

Post  pinhedz on Wed Dec 14, 2011 5:23 am

Let's try an experiment: Flip a coin 20 times.

I predict that your coin will not land heads-up 20 times in a row.
Am I certain? Well I'm pretty darned sure anyway.

In fact, if I watched a coin land heads up 20 times in a row, I would begin to question my own sanity and senses.

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Re: ET call home

Post  Andy on Wed Dec 14, 2011 7:51 am

While I think I'm basically agreeing with most of what you say, I would like the use a demonstration of why I find the 'flipping coins'-analogy inadequate to point out where I think I'm taking a different perspective.

Bear in mind that the question at hand is the existence life on another planet.

What is the situation we are presented with when flipping a coin?
One in which we know that a certain procedure must lead to either one of the 2 predeterminate outcomes.
It can not be so that there is no outcome and wathever the outcome is, we already know the 2 options in advance.
How likely is it that certain patterns will or will not arrive when we repeat this procedure often enough?
Well, that's what statistics are for.
And you're absolutely right in using them to voice your belief that I won't be able to repeat the exact same outcome over a certain number of consecutive trials.

But can we compare this situation with the one in which we ask for the actual existence of being?
While it might be tempting to answer 'yes' to this question, I would like to present a counter example to demonstrate that this really is a different sort of question.
Suppose I showed you a coin that you have never seen before in your life, but I only show you the side that indicates the coins value.
I declare to you that on the heads side there is a portrait of a man who once held an important political function in the country that issued the coin.
Could statistics ever provide you with a similar degree of confidence to judge wether or not my declaration is true as in the previous example?
Sure, I could show you statistics that tell you what percentage of issued coins hold portraits of male politicians and all but I can't see how you could ever attain a similar degree of probability as in the previous example.

Personally I find the process of assuming the existence of a being from purly statistical motivation a modern variant of a well-known but very problematic style figure: the ontological argument.
The medieval rationality which thought in terms of essences rather than numbers achieved a culmination in its demontration of the actual existence of a being from logical inquiry into its essence.
The modern mind might be tempted to take a similar chance in postulating the necessity of the existence of a being - and I'm not saying this is how far you're taking things, let that be clear - upon the grounds of its sacred math.

As an after-thought I also find it quite funny how in this debate existence is linked up with probability while some closer reflection upon statistics must teach us that each and every being we actually know to exist is extremely improbable. From the Big Bang to you staring at this computer screen in your own here and now, seriously: what are the odds to that happening? It's hard to think of anything even less likely. The figures that are used to demonstrate the probability of extra terrestrial life - how enormous they might seem - are dwarfed by an immense order of magnitude by the figures that demonstrate how improbable each and every one of us is.

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Re: ET call home

Post  pinhedz on Wed Dec 14, 2011 12:30 pm

The improbable becomes inevitable given sufficient time. If you flip a coin over and over, it is inevitable that eventually you will get 20 heads in a row.

Inevitable--not just highly likely.

Statistical analysis is much more trustworthy than an eye witness. What a Face

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Re: ET call home

Post  Guest on Wed Dec 14, 2011 12:33 pm

alien

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Re: ET call home

Post  Andy on Thu Dec 15, 2011 8:21 am

pinhedz wrote:
Inevitable--not just highly likely.

Cool - but 2 questions:

1. How do you calculate 'x' if 'x' = the number of times one has to toss a coin so as to be 100% sure that it has come up the same side 20 times in a row;

2. Is there an upper limit to this? That it becomes 'highly likely' that this configuration will appear in reality if you persist long enough seems plausible to my intuition. But if I up the 20 to 20 billion times in a row it actually becomes highly unlikely to my intuition. And yet if it is possible to calculate the X from question 1, there must be a method to find 'X2' which tells us how many times we have to toss to be 100% sure that the coin has flipped to the same side a staggering 20 billion consecutive times;


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Re: ET call home

Post  pinhedz on Thu Dec 15, 2011 1:55 pm

andy wrote:And yet if it is possible to calculate the X from question 1, there must be a method to find 'X2' which tells us how many times we have to toss to be 100% sure that the coin has flipped to the same side a staggering 20 billion consecutive times; ...
There is a method, but it won't give a specific X (or "N," which is more usual for integers). The probability function P(N) is a function of N were N is the number of flips. P(N) will be less than 1 (i.e. less than 100%) for any number of flips that is finite. For some very large N the probability will be 99.99999999999999999999999999999999999999999999999999999999%. For some much larger N, there will be a billion 9s, or any number of 9s you can name, but P(N) will not be 100% for any finite N.

But when I said "given sufficient time," that means there is no limit on time or the number of flips--you keep flipping until it happens.

In mathematical notation, you would integrate the probability function over the number of flips N, where N goes from N = 0 to N = INFINITY.

The integral of the probability function integrated from N = 0 to N = INFINITY will be 1 (100%).

There is no such thing as failure in this exercise because there is no giving up until you succeed (i.e., you don't stop at any finite number). As long as you haven't flipped 20 billion heads in a row, that just means you keep flipping.

And it will happen at a finite number N (even thought the calculated P(N) will be less than 1). It could happen at P(N) = 50%, or P(N) = 99%, etc. It can happen at P(N) = any number; it could even happen on the first try. Infinity can't be the destination because infinity isn't actually a number.

In other words, you will, with 100% certainty, get 20 billion heads in a row because you won't stop until you do.

Just as we know INFINITY isn't a number, we also know that NEVER is not a number either.

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Re: ET call home

Post  Andy on Thu Dec 15, 2011 5:59 pm

So unless you would be able to prove that the universe is infinte in its materiality, statistics could never guarantee us with 100% certainty that there is at least one other planet with life on it.

Correct?

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Re: ET call home

Post  pinhedz on Thu Dec 15, 2011 11:37 pm

Correct, but I'm not sure what you are getting at.

I think we started with this:

pinhedz wrote:I think that most scientists believe there are other planets like ours.
Anything wrong with that?

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Re: ET call home

Post  Andy on Fri Dec 16, 2011 1:46 am

I already answered that question:

Andy wrote:While I think I'm basically agreeing with most of what you say, I would like the use a demonstration of why I find the 'flipping coins'-analogy inadequate to point out where I think I'm taking a different perspective.

So nothing wrong with that.

I'm not entirely sure how you manage to go from:

pinhedz wrote:In fact, if I watched a coin land heads up 20 times in a row, I would begin to question my own sanity and senses.

to

pinhedz wrote:In other words, you will, with 100% certainty, get 20 billion heads in a row because you won't stop until you do.

in the space of a single page. But that's irrelevant to the matter at hand.

P.S.: I do know 'infinity' is part of the answer, yes. Still: going from questioning your own sanity if a result is produced 20 times to assuring that it must be produced 20 billion times - you gotta admit it sounds a bit fishy.

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Re: ET call home

Post  pinhedz on Fri Dec 16, 2011 3:36 am

Andy wrote:P.S.: I do know 'infinity' is part of the answer, yes. Still: going from questioning your own sanity if a result is produced 20 times to assuring that it must be produced 20 billion times - you gotta admit it sounds a bit fishy.
I don't know why that's fishy--after all, the number of flips I could execute in my lifetime is infinitesimal. To say 20 billion heads is inevitable is not the same as saying we would expect to ever see it. Nonetheless, given unlimited time, heads 20 billion times is just as inevitable as heads one time.

Yes, I really said that--heads 20 billion times is just as inevitable as heads one time.

If you flip a coin 20 times, are you 100% certain you'll get heads even once? How about 200 times? If you flip a coin 20 billion times, are you 100% certain you'll get heads at least once? The answer is No for any finite number, but yes if the limit is infinity--whether we're talking about heads one time or 20 billion times.

As for my being crazy, there is some probability of that (I'd say it's a low probability) and there is also a probability (also low) of 20 heads in a row. On balance, I think the probability that I am crazy is higher than the probability of 20 heads in a row. That is why I would question my own senses.

Unless of course I actually kept flipping until I could reasonably expect to get 20 heads in a row, in which case I would certainly (with 100% certainty) have to be crazy. geek

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Re: ET call home

Post  eddie on Fri Dec 16, 2011 8:35 pm

From the ZD Net UK site:

That Random Coin Toss?

By timdaily , 13 December, 2009


One of my all-time favorite scenes in a play and movie, is the scene in Tom Stoppard's Rosencrantz & Guildenstern Are Dead where every coin toss comes up heads, leading to a bit of a philosophical discussion on probability. Of course, the randomness of the coin toss is the quintessential example of a random event and is used regularly for a variety of situations in which randomness is required, let alone expected. Except... it turns out the common wisdom may be wrong. Paul Kedrosky has the news of a test that showed that if you ask people to try flip a coin and get more heads than tails, they will, and not by a small margin either. In the test, 13 people were asked to flip a coin 300 times, trying to get as many heads as possible. All 13 participants got more heads than tails. Seven out of the thirteen had statistically significant margins of heads over tails (meaning almost certainly not a matter of chance). The highest was one individual had 68% of the coin flips land heads. In other words, a coin toss isn't particularly random

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Re: ET call home

Post  eddie on Sun Jan 15, 2012 4:03 am


Berger & Wyse.

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Re: ET call home

Post  eddie on Thu Jan 26, 2012 10:47 pm

http://www.youtube.com/watch?v=ZPvau0RBYPk&feature=related
Waiting For the UFO's- Graham Parker & The Rumour.

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Re: ET call home

Post  eddie on Sun Mar 18, 2012 4:57 am


Stephen Collins

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Re: ET call home

Post  eddie on Sat Apr 07, 2012 7:17 pm


Stephen Collins

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Re: ET call home

Post  pinhedz on Tue Dec 23, 2014 11:16 am

"Where Is Everybody?": An Account of Fermi's Question
Eric M. Jones, Los Alamos National Laboratories
original source | fair use notice

Summary: Fermi's Famous question, now central to debates about the prevalence of extraterrestrial civilizations, arose during a luncheon conversation with Emil Konopinski, Edward Teller, and Herbert York in the summer of 1950. Fermi's companions on that day have provided accounts of the incident.

Part of the current debate about the existence and prevalence of extraterrestrials concerns interstellar travel and settlement [1-3]. In 1975, Michael Hart argued that interstellar travel would be feasible for a technologically advanced civilization and that a migration would fill the Galaxy in a few million years [4]. Since that interval is short compared with the age of the Galaxy, he then concluded that the absence of settlers or evidence of their engineering projects in the Solar System meant that there are no extraterrestrials.

Newman, Sagan, and Shklovski [2,5] recall that a legend of science says that Enrico Fermi asked the question, "Where are they?" during a visit to Los Alamos during the Second World War or shortly thereafter. Fermi's question has been mentioned in several other recent publications, but historical basis for the attribution has not been established. Thanks to the excellent memory of Hans Mark, who had heard a retelling at Los Alamos in the early 1950s, we now know that Fermi did make the remark during a lunchtime conversation about 1950. His companions were Emil Konopinski, Edward Teller, and Herbert York. All three have provided accounts of the incident.

We begin with Konopinski: "1 have only fragmentary recollections about the occasion.... I do have a fairly clear memory of how the discussion of extra-terrestrials got started while Enrico, Edward, Herb York, and I were walking to lunch at Fuller Lodge.

"When l joined the party, I found being discussed evidence about flying saucers. That immediately brought to my mind a cartoon I had recently seen in the New Yorker, explaining why public trash cans were disappearing from the streets of New York City. The New York papers were making a fuss about that. The cartoon showed what was evidently a flying saucer sitting in the background and, streaming toward it, 'little green men' (endowed with antennas) carrying the trash cans. More amusing was Fermi's comment, that it was a very reasonable theory since it accounted for two separate phenomena: the reports of flying saucers as well as the disappearance of the trash cans. There ensued a discussion as to whether the saucers could somehow exceed the speed of light."

Teller remembers: "My recollection of the event involving Fermi . . . is clear, but only partial. To begin with, I was there at the incident. I believe it occurred shortly after the end of the war on a visit of Fermi to the Laboratory, which quite possibly might have been during a summer.

"I remember having walked over with Fermi and others to the Fuller Lodge for lunch. While we walked over, there was a conversation which I believe to have been quite brief and superficial on a subject only vaguely connected with space travel. I have a vague recollection, which may not be accurate, that we talked about flying saucers and the obvious statement that the flying saucers are not real. I also remember that Fermi explicitly raised the question, and I think he directed it at me, 'Edward, what do you think? How probable is it that within the next ten years we shall have clear evidence of a material object moving faster than light?' I remember that my answer vas ' 1 o-6.. Fermi said, 'This is much too low. The probability is more like ten percent' (the well known figure for a Fermi miracle.) "

Konopinski says that he does not recall the numerical values, "except that they changed rapidly as Edward and Fermi bounced arguments off each other."

Teller continues: "The conversation, according to my memory, was only vaguely connected with astronautics partly on account of flying saucers might be due to extraterrestrial people (here I believe the remarks were purely negative), partly because exceeding light velocity would make interstellar travel one degree more real.

"We then talked about other things which I do not remember and maybe approximately eight of us sat down together for lunch." Konopinski and York are quite certain that there were only four of them.

It was after we were at the luncheon table," Konopinski recalls, "that Fermi surprised us with the question 'but where is everybody?' It was his way of putting it that drew laughs from us ."

York, who does not recall the preliminary conversation on the walk to Fuller Lodge, does remember that "virtually apropos of nothing Fermi said, 'Don't you ever wonder where everybody is?' Somehow . . . we all knew he meant extra-terrestrials."

Teller remembers the question in much the same way. "The discussion had nothing to do with astronomy or with extraterrestrial beings. I think it was some down-to-earth topic. Then, in the middle of this conversation, Fermi came out with the quite unexpected question 'Where is everybody?' . . . The result of his question was general laughter because of the strange fact that in spite of Fermi's question coming from the clear blue, everybody around the table seemed to understand at once that he was talking about extraterrestrial life.

"I do not believe that much came of this conversation, except perhaps a statement that the distances to the next location of living beings may be very great and that, indeed, as far as our galaxy is concerned, we are living somewhere in the sticks, far removed from the metropolitan area of the galactic center."

York believes that Fermi was somewhat more expansive and "followed up with a series of calculations on the probability of earthlike planets, the probability of life given an earth, the probability of humans given life, the likely rise and duration of high technology, and so on. He concluded on the basis of such calculations that we ought to have been visited long ago and many times over. As I recall, he went on to conclude that the reason we hadn't been visited might be that interstellar flight is impossible, or, if it is possible, always judged to be not worth the effort, or technological civilization doesn't last long enough for it to happen." York confessed to being hazy about these last remarks.

In summary, Fermi did ask the question, and perhaps not surprisingly, issues still debated today were part of the discussion . Certainly, the line of argument that York remembers became familiar a decade later as the Drake-Greenbank Equation [6,7].

A final point: the date of the conversation. York is clearest on the date. "The conversation was either in the summer of 1950, 1951, or 1952, very probably 1951, and took place . . . when I was visiting LASL in connection with the forthcoming Greenhouse tests - specifically, the George shot." The George test occurred on May 8, 1951, suggesting a 1950 date. Surviving correspondence from the time indicates that Fermi was an annual summer visitor during the years in question. Unfortunately, attendance and travel records for those years have been destroyed. However, we have the evidence of the cartoon Konopinski mentions. Drawn by Alan Dunn, it was published in the May 20, 1950, issue of The New Yorker. It seems quite probable that the incident of Fermi's question occurred in the summer of 1950.

I am grateful to Hans Mark and to the three surviving participants for their accounts. These accounts, together with my letters of inquiry, are reproduced in the following pages.

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Re: ET call home

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