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CraigS
25-02-2011, 10:59 AM
Been doing some reading this week, and have encountered some interesting facts. As a result, I thought it may be interesting to start a thread to capture some factual, counter-intuitive snippets. (The counter-intuitiveness, of course, depends on the viewer) ;).

Here’s a couple I’ve encountered this week (credits to others):

Gravity:
1. The force on a point mass decreases as (1/r^2), when the mass is located outside the sphere. If the sphere is hollow, the force on a point mass inside the sphere is zero, and is independent of r. If the sphere is solid, and of uniform density, the force on a point mass inside the sphere, decreases with decreasing radial distance between the point mass and the centre of the sphere (decreases linearly with r).

2. Imagine an infinitely long line of mass (ie: a cylinder). The acceleration, ‘g’, due to the gravity of the line mass, at a perpendicular distance r from the mass, decreases as (1/r). (The ends contribute zero gravity).

3. Imagine an infinite plane of mass. The acceleration, ‘g’, due to the gravity of the plane at a perpendicular distance r from the plane, is a constant ! Ie: the acceleration due to gravity for an infinite plane of mass, is completely independent of the distance, r, from the plane!

Time and Quantum Mechanics:
4. Time is not an observable quantity in quantum mechanics.
5. In quantum mechanics, the observer and the observed, can be one in the same.
6. If something isn't observed, then it can be said to be in all states simultaneously.

Interesting ... please feel free to contribute any other counterintuitive facts you may have encountered !
(I suggest contributers stick with ‘facts’ which can be demonstrated and are reproducible. ;) )

:)

Cheers

renormalised
25-02-2011, 11:06 AM
Here's one...when you're overtired you actually don't feel tired:)

CraigS
25-02-2011, 01:35 PM
Good one ...!!…
(I don't want to be the test subject, mind you).
:)
I find it actually quite tricky to state a fact.
Stating a counterintuitive one makes it ... 'interesting' ..
:)

Cheers

sjastro
25-02-2011, 02:23 PM
One that you are familiar with Craig.

Excluding a vertical straight wire, what should the shape of a wire be such that a bead released from one end of the wire will slide to the opposite end under gravity in the shortest period of time.

Common sense says the wire should be straight but the answer is in fact a cycloid.
http://en.wikipedia.org/wiki/Cycloid

Regards

Steven

renormalised
25-02-2011, 02:45 PM
From a photon's point of view it sees the entire universe instantaneously, yet it takes light 8.3 minutes to get from the Sun to us. Yet both facts are true.

ballaratdragons
25-02-2011, 03:04 PM
You don't die, or explode, of liquify or anything else 'instantly' in the vaccuum of space like they do in movies.

Even without a spacesuit It is possible to live in the vacuum of space for up to 3 minutes.
So if you accidentally fell out of an airlock (I don't know how you can 'accidentally' fall out of an airlock :lol: ), you could be rescued if others are quick enough to get you.
Fact :thumbsup:

CraigS
25-02-2011, 03:56 PM
Interesting .. I'm enjoying this thread !
:)
Just so we can justifiy this thread in the Science Forum, (and for the record), I found a reasonable definition of scientific 'fact':



.. oh .. what the hell .. here's the rest of 'em … :) …



Keep 'em coming !! I'll probably update this thread when I uncover some more of my own, in the future !
:)
Cheers (& thanks for the contributions !)

Bassnut
25-02-2011, 04:27 PM
Parallel lines meet at infinity?.

mjc
26-02-2011, 09:23 AM
0.9999 (recurring) is identical to 1 and not infinitesimally smaller than one.

Proof divide one by three
1/3 = 0.33333 (recurring)

Multiply both sides by three

1 = 0.99999 (recurring)

http://en.wikipedia.org/wiki/0.999...

Mark C.

OICURMT
26-02-2011, 11:08 AM
Could you supply a reference for this? I'm struggling to figure this out, as the partial pressure of H2O under a vacuum at body temperature would result in boiling...


I could surmise that the body itself must be under pressure due to "containment" by the epidermis... but don't know if that would be enough.

CraigS
26-02-2011, 11:45 AM
Ok .. so this one's got me stumped, also.
(I'm sure what Steven says is correct, but my brain needs more !! :) )

If a vertical wire is fastest of all, then why wouldn't a wire, slightly off the vertical, also be faster than a Brachistochrone Curve (cycloid) ?

If such a wire did result in a faster descent, then there must be an angle at which it wouldn't be a faster descent .. what is that angle if friction is excluded ? :question:

(The second question may be irrelevant if the inference in the first question is proven invalid. I suspect the issue here is in the wording. There is something about the bead having to be 'constrained'. It would appear that there must also be constraints applying to the end-points, as well. (??). I'm not sure of the significance of these constraints, however .. ).

Cheers

sjastro
26-02-2011, 02:30 PM
Craig,

It depends if a cycloid can be formed in the first place.
The vertical wire not only takes of the shortest distance and time, but also a cycloid cannot reach the bottom point if the endpoints are vertically aligned.

If the wire is even slightly off vertical the cycloid path will take the shortest time if it is able to reach the lower point.

Regards

Steven

mithrandir
26-02-2011, 05:39 PM
I think you will find that the vertical wire is the limit case of the brachistochrone when the points become vertically aligned. I don't feel up to remembering enough of my Calculus of Variations course - more than 30 years ago - to prove it.

Andrew

sjastro
27-02-2011, 06:28 AM
What you will find is that the partial derivatives in Euler LaGrange equation vanish as there is no horizontal component. This reduces the equation to the trivial case 0=0. There is no stationary value.

From a physics perspective since the wire is frictionless, the wire does not provide a constraint when the endpoints are vertical. The bead falls purely under the effect of gravity which is in a straight line.

Regards

Steven

mithrandir
27-02-2011, 07:52 AM
However, the function [image that won't paste] is particularly nice since x does not appear explicitly. Therefore, [another image] and we can immediately use the Beltrami identity ...
http://mathworld.wolfram.com/BrachistochroneProblem.html

Are you suggesting there is no limit as delta x approaches zero, and the the vertical line is a discontinuity? Physics and discontinuities don't get on well together.

Doesn't that assume a non-rotating frame of reference? A falling object in a rotating frame follows a parabola. (Ignoring any effects of air resistance.)

sjastro
27-02-2011, 10:07 AM
The Beltrami identity doesn't apply.
If you look at equation (4) if the endpoints are vertical, dx=0 hence ds=dy.
The integrand in equation (6) becomes dy/(2gy)^.5

The functional (http://en.wikipedia.org/wiki/Functional_(mathematics)#Integral ) in this case is of the format f(y, x, x')dy not
f(x, y, y')dx as in the mathworld link where there is both a vertical and horizontal component of the endpoints.

In the f(y,x, x')dy format the partial derivatives of the Euler Lagrange equation are with respect to x and x' (for f(x,y,y')dx are these are with respect to y and y').

Since x and x' do not appear explicitly in the integrand, all the partial derivatives in the Euler LaGrange equation are zero.
Hence we have the trivial case of 0=0.



I'm not sugesting anything of the kind.

The Euler Lagrange equations applies to functionals not functions. A functional that satisfies the EL equation has a stationary or extremal value. Vertical endpoints are simply a particular case. Here the functional does not have a stationary solution.



The Brachistrome problem assumes there are no fictitious forces.

Regards

Steven

OneOfOne
28-02-2011, 07:13 AM
I recall seeing something like this on "Why is it so?". They had a series of clear tubes finishing at a lower point to one side, each with a ball inside, one straight, one cycloid, one parabolic. All three balls were dropped simultaneously, with the one in the cycloid finishing first. Do we have a dilemma? :) Loved that show!

CraigS
28-02-2011, 08:51 AM
Changing the topic slightly … I love Mark's (mjc's) contribution !!

Such simplicity … tremendous stuff !

Hard to top that one … a real beauty !
:)

Cheers

renormalised
28-02-2011, 10:05 AM
Here's a counterintuitive fact.....Anthony Peratt = plasma cosmology/EU advocate (nut) = respected scientist :):P:P

CraigS
28-02-2011, 10:31 AM
Actually, I'm going to have to (sort of) challenge part of that one … from the Los Alamos National Laboratory 'Plasma Universe' (http://plasmauniverse.info/) website …



Now, whilst the Los Alamos Laboratory site doesn't fully represent Peratt's views, this IS where most of his papers are found, and he IS quoted on their homepage, and he WAS a 'Member, Los Alamos National Laboratory Associate Directorate for Experiments and Simulations, 1999–2003".

… close ... but I don't know that we can assume he's an EU advocate (nut).

Perhaps a co-conspirator of a slightly different ilk ??? :question:

… perhaps a 'plasma cosmology (nut)' ??? :question:

:P:)
Cheers

renormalised
28-02-2011, 10:42 AM
And yet he comes out and publishes a paper like this...

"Characteristics for the Occurrence of a High-Current, Z-Pinch Aurora as Recorded in Antiquity"

I think the conclusions of this paper fairly and squarely put him in the EU nut category without a shade of doubt. Even if LANL or he, himself, doesn't think so.

The archaeologists (apart from others) would be having fits of laughter if they ever read that paper:):P

CraigS
28-02-2011, 10:44 AM
Problem there is … what is EU ?
… I don't think even they know ..
:)

Cheers

renormalised
28-02-2011, 10:48 AM
A very good point:)

Which is also counterintuitive because you'd think they would know:):P

CraigS
28-02-2011, 10:51 AM
.. boom .. boom …
:lol:

Can't argue with that one !!
:lol: :)

Cheers

renormalised
28-02-2011, 10:55 AM
They would. But, hey, what would you expect:):P

Brian W
28-02-2011, 01:28 PM
with absolutely no attempt at humour or modesty this thread has shown me just how much education I am lacking.

And an honest thanks for taking the time to occasionally dumb things down so I can begin to understand things.
Brian

CraigS
28-02-2011, 01:54 PM
Gee Brian;

1/3 and 3 x 1/3 isn't all that hard.

:sadeyes:

:P :)

Cheers

ballaratdragons
28-02-2011, 02:24 PM
Here's a few links. There are lots of them.

http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19650027167_1965027167.pdf

http://www.geoffreylandis.com/vacuum.html

http://imagine.gsfc.nasa.gov/docs/ask_astro/answers/970603.html

http://www.accessplanetary.com/space/how-long-can-you-survive-in-space-without-a-space-suit

http://space.about.com/cs/basics/a/bodyvacuum1.htm

etc
etc :thumbsup:

bojan
28-02-2011, 02:46 PM
EU stands for European Union :P

CraigS
28-02-2011, 02:54 PM
Doh !! Of course !!

… sheer genius, I tell ya, sheer genius !!

:)

Cheers

renormalised
28-02-2011, 04:10 PM
They don't even know what they're on about, either :):P

OICURMT
28-02-2011, 07:25 PM
Too cool... thanks.



Now I have a valid reason for getting fat... must be the vacuum in my head ;)

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sjastro
01-03-2011, 12:22 PM
Another interesting property of a cycloid is that if the object is released from any point on the cycloid it will take the same time to reach the bottom.

Regards

Steven

avandonk
01-03-2011, 01:56 PM
Nearly all of science is counterintuitive. It has taken thousands of years by many very smart people to work this out.

You only have to look at some of the ancient Greek 'laws' of science.

For a constant velocity a constant force needs to be applied.

Experimental proof. When the force is removed the object stops.
There was an anomaly with arrows, spears and rocks. But it was proposed that force supplied by the air from the thrower kept the object in flight.
Sound familiar as a fudge factor?

There were four elements whose correct place was earth at the lowest point then water, air and fire. It was evil that kept misplacing these elements.

Experimental proof.
Earth sank in water. Air rises in water. Fire rises in air. And all the other combinations.

The Sun, Moon, Wanderers (planets) and stars go around the earth.
Experimental proof.
Go outside and look at the sky. It is exceedingly obvious!

I could go on for a very long time, but I am sure you could come up with your own version.

Bert

CraigS
01-03-2011, 03:12 PM
Thanks Bert … cool … our paradigms of understanding (which change over time), are an an essential part of our intuitiveness.

Here's another interesting one .. The Archer's Paradox (http://en.wikipedia.org/wiki/Archers_paradox) (done a bit of this in my past, so I can confirm the validity of it from first hand experience ..)

In order to strike the center of the target, an the arrow shot from a bow, must be pointed slightly to the side of the target.

The stiffness of the arrow determines whether (or not) it clears the bow (without striking it on the way out).

Here's why (http://www.texasarchery.org/Photos/LloydHS/Sung-HyunPARKKOREAArrow.WMV) … its like a lump of wet spaghetti … (I never tire of watching hi-speed video of this .. amazing !)

Cheers

avandonk
01-03-2011, 06:51 PM
You totally missed my comment on fudge factors Craig. If ancient Greeks needed to invoke some sort of mythical air propulsion against their known theory of mechanics it only showed they did not have a fully developed theory.

We find ourselves in the same conundrum with dark energy and dark matter.

I still think it is all the quantum entanglements that are still linking all possible particle interactions for all time!

Bert

Screwdriverone
01-03-2011, 07:43 PM
Just thought of one, not sure if it qualifies......

If you lose something and go looking for it in multiple places and then find what you were looking for, it will ALWAYS be in the LAST place you look. Even if you find it in the FIRST place you looked, it will ALWAYS be the LAST place you looked for it....

??? (don't hurt me)

Cheers

Chris

CraigS
02-03-2011, 06:24 AM
Well Chris;
I suppose even Irish Logic is counterintuitive …
:lol: :)
Cheers
PS: No disrespect to any Irish Logicians out there !! :)

mjc
02-03-2011, 12:05 PM
Or very intuitive - but counter expected logic-

A tourist in a village outside of Dublin asks a local, "What's the best way to get to Cork?"

Local: "Well that depends - are you on foot or do you have a car?"

Tourist: " I have a car"

Local: "Well, that's the best way!"

Mark C (living in suburbs of Dublin)

Robh
02-03-2011, 12:28 PM
Hi Craig and all,

For counter-intuitive, you can't go past this one from the mathematicians.
It is possible to take a solid sphere S and divide it up into a finite number of pieces and then reassemble them (using only translations and rotations) into two identical copies of the original sphere. This is known as the Banach-Tarski Paradox.
In fact, ignoring the original sphere's centre, it can be divided into precisely 4 pieces S1/S2/S3/S4 that can be re-assembled into two spheres S1+S2 and S3+S4 each of the same volume as the original.

A more impressive statement of the theorem says that it is possible to take a solid sphere the size of a pea and divide it into a finite number of pieces that can be reassembled into a sphere the size of the Sun.

Regards, Rob.

mjc
02-03-2011, 12:30 PM
Mathematics is a rich source of counter-intuitive facts.

There are some infinities that are "bigger" than others.

http://en.wikipedia.org/wiki/Infinity#Cardinality_of_the_continu um

Take the natural numbers (counting numbers - whole numbers) - one can have an infinite number of them.

Now consider the real numbers (those numbers that can have arbitrary decimal precision). There are an infinite number of numbers between 0 and 1 and between 1 and 2 - in fact between any two decimal numbers.

These two infinities are of different scale.

Cantor had real resistance to this idea.

Mark C.

mjc
02-03-2011, 12:35 PM
Rob

That's one that I've heard of - but that is seriously beyond my comprehension.

Mark C.

Screwdriverone
02-03-2011, 01:33 PM
:lol:

That one is a bit like the blonde walking along the banks of a river, she sees another blonde across the river and calls out: "HEY!, how do you get to the other side?" To which the other blonde says: " You ARE on the other side!".....

Cheers

Chris

Robh
02-03-2011, 01:47 PM
Mark. I think the proof is one for mathematicians with specific knowledge of set theory.
But your previous post gives an analogy.
Consider the set of positive integers Z:
1,2,3,4,5,6,7,8,9,...
This is, of course an infinite set.

Now lets split it into even numbers:
2,4,6,8,10,12...
and odd numbers
1,3,5,7,9,11,...
Both infinite sets.

Take the even numbers and divide by 2:
2/2,4/2,6/2,8/2,10/2,12/2... = 1,2,3,4,5,6... which is the same as set Z
Take the odd numbers subtract 1 then divide by 2:
(1-1)/2,(3-1)/2,(5-1)/2,(7-1)/2,(9-1)/2,(11-1)/2... = 0,1,2,3,4,5... which, if the zero is ignored, is also the same as set Z.

Thus set Z is split into two sets each of the same size as Z.

Rob

sjastro
02-03-2011, 01:59 PM
I suppose this thread can evolve from the counterintuitive to the incomprehensible, such as the Klein bottle which is a two dimensional object that can only exist in four dimensions.

Klein bottles however can be purchased.:D
http://www.kleinbottle.com/

I like the Acme Klein Bottle lifetime guarantee.

:lol:

Regards

Steven

CraigS
02-03-2011, 02:08 PM
Thanks all. I appreciate everyone's contributions on this thread .. I think its terrific.

I suppose if I had to disclose my point in raising this thread, I would have to make use of the following two quotes (thanks to Bert and Mark):





Science would have to be counterintuitive, because science is fundamentally built on rationality. Wiki defines rationality as:



And mathematics I think, is an essential part of that strategy.

The counterintuitiveness arises when we compare our expectations, (which aren't always rational ... as the above quote asserts), with the outcomes of a rational process.

Thanks to everyone for the previous examples. I don't think any one of them could escape being put to the test using mathematics, as the litmus test for rationality and ultimately, factuality.

The embedding of mathematics within Science, is so often accused of divorcing science from reality and yet, all I can see is that its presence prevents us from deluding ourselves, and being solely dependent on frequently flawed human 'intuitiveness'.

I see this as being particularly important in astronomy, as I find it easy to get caught up in the aesthetics and the deceptiveness of the image ..

Cheers

CraigS
02-03-2011, 05:37 PM
Rob;
I'm havin' trouble with this one, too.
There's some tricky wording around how to do this …


So what exactly is an infinite scattering of points if:


I guess I need a refresher on my set theory definitions … :question:
:)
Cheers
PS: Clearly a pea and the Sun have different masses. So, there's some trickiness around what these 'points' actually are. Seems to me, this maybe one which exists in set theory, but may not necessarily have a one-to-one mapping with the physical world :question:

Robh
03-03-2011, 09:28 AM
Craig,

The concept challenges the way we think about volume. When we calculate volume, we give it in terms of so many m^3, cm^3 or mm^3. But why stop there? We could give it as so many nanometres^3 or picometres^3. In fact we could give it as the number of atoms of hydrogen gas that make up that volume.
I think the idea is that the sphere is considered to be made up of an infinite number of lattice points rather than a finite number of individual atoms. Analogous to the concept that an interval consists of an infinite number of points rather than a finite chain of atoms.
In that sense, the sphere could not be physically divided into 4 pieces (ignoring the centre) that can be reassembled into two identical spheres as the original. Simply because the sphere cannot be physically divided down past the size of an atom. It is probably best to think of each divided piece as a cloud of an infinite number of points scattered in the lattice of the sphere.
From my understanding, the paradox says nothing about the shape of the pieces. They may appear as a random framework of an infinite number of points that are loosely connected. However, remember also that physically atomic nuclei are actually strung out in a lattice with spaces between them.
As a theoretical possibility, the concept of division of a solid sphere into a finite number of pieces and then reassembly into two copies of itself is still extraordinary.

Regards, Rob

multiweb
03-03-2011, 09:41 AM
Here's another one: drinking more alcohol dehydrates you... not fair. :P

CraigS
03-03-2011, 09:49 AM
Yes thanks for that Rob;

I was thinking along similar lines, but I wasn't sure if I was getting the point.

If (theoretically), you keep dividing an atom into more and more smaller particles, you end up drifting towards all that string theory stuff, which we've discussed before. However, from a QM point of view, we can't get smaller than Planck size so, this would seem to be where theory departs from practice, eh (??) (Ie: in practice, there's an asymptotic limit ?)

If this is the case, then I think this paradox may fit in the theoretical box. :question:

Cheers

CraigS
03-03-2011, 09:56 AM
I reckon you should keep working on that one, Mark.

Here's the next step … drinking too much water can kill you …
Water intoxication (http://en.wikipedia.org/wiki/Water_intoxication) .. looks like Andy Warhol, (& others), (http://en.wikipedia.org/wiki/Water_intoxication#Notable_cases) died from it.

Better stick with the alcohol … (safer).
:)

Cheers

multiweb
03-03-2011, 10:38 AM
Wow! Scary... You gotta die of something. I'd rather go with a nice after taste of good Port than chlorine :)

troypiggo
03-03-2011, 11:56 AM
2 of my favs:

You can't slam a revolving door.
You can't grow beer in a beer-garden :(

Not very scientific, sorry.

gman
03-03-2011, 04:33 PM
Something simple
-40 Celcius = -40 farenheit

Somthing hard
Double slit experiment
www.youtube.com/watch?v=DfPeprQ7oGc

CraigS
27-03-2011, 07:58 AM
Hi Folks;
Its been bugging me, so the best way (I figure) for me to get this off my chest, without annoying everyone forever after, is to resurrect this thread and record the fact.

So here comes the counterintuitve fact …

(Full credits to Bert: Thanks Bert).

(There are many other examples, but I love the simplicity of this one).

So now for the non-fact (speculative side of this):
I can't help wondering about the possibility that life in the universe may have emerged following this same pattern, ie: it can still obey all of the known Laws of Physics, but may still not have a repeatable outcome. I emphasise that there is no evidence that this is possible, but there is also no evidence to the contrary. Inferences can be made, and these are entirely dependent on the frequency of occurence of the 'right conditions', suitable for the emergence of life.

So, I emphasise that the possible non-deterministic nature of exo-life emergence idea, is purely speculative (and somewhat tenuous) on my part.

I can't resist refraining from looking at the huge the diversity of exo-environments, staring us square in the face, and wonder about mainstream science's propensity for leaning towards classical deterministic physics, to explain it all. Whilst predictable, replicated patterns clearly exist in the universe, on other scales, they don't. We seem to be living amongst a mixture of systems defined by both deterministic and non-deterministic physics. Scientists look for constraint limits, when exploring seemingly complex phenomena, and if observations align with classical, deterministic physics, the unknowns are then unable to influence the explanations. (Ie: we don't know what we can't explain with deterministic physics).

Quantum mechanics has taken us part of the way into this world, and may apply at the smaller scales, but does this mean that non-deterministic physics can't explain phenomena at other scales, and in other areas ?

All of this exo-life idea will instantly change of course, once a single instance of exo-life is found.

I just love the frailty and precariousness, of the exo-life situation in science. Tremendous stuff !

Another comment (by Robh) the other day nudges me along even more:
… And the pattern continues in other areas …

Incredible stuff !
I'm done ! Comments welcome.
:)
Cheers

avandonk
27-03-2011, 09:47 AM
Craig even life on Earth would not follow the same evolutionary path given the exact same starting conditions. Evolution is a random process only constrained by the laws of physics and chemistry.

Of the many life forms with different body morphologies that were produced in the pre Cambrian explosion only a few survive today. All mammals have essentially the same body plan. From whales to mice.

The same rules would apply to exolife and exoevolution.

The brick pulled by a rubber band on an inclined plane of carborundum paper is a very good model for fault behaviour driven by tectonic plate movement. Where the pull is tectonic plate movement. The rubber band is the energy in the rock and the sudden movement of the brick is the earthquake.

There is a new program on SBS on 0830 PM tues 5th of April all about fractals chaos etc and the associated mathematicians and mathematics. Did you see the very early fractal animals on David Attenborough's First Life?
I only heard about this on the Science Show yesterday.

The counter intuitive thing that comes out of chaotic systems and fractals is that self regenerating order can arise from total randomness. LIFE!

The underlying quantum mechanics just gives us a glimpse of the connectedness of all matter and energy at a multidimensional level we cannot perceive directly.

Bert

Brian W
27-03-2011, 11:12 AM
Hi Craig, you were doing great right up to the point where you said that all of your speculation changes once a single instance of exo life is found.

No it doesn't it just means one and only one form has been found.

Humanity has always made itself the centre. Centre of the universe... wrong, centre of the galaxy... wrong, centre of the solar system... wrong.

Admittedly deciding where a ship is going next from its wake is a pretty dumb idea but if history holds true carbon may well not be the unalterable necessity for life many think it is.

Not that there will not be carbon based life forms but there may not be. And not there are life forms using a non carbon structure but there may be.

It is after all one incredibly huge place we inhabit with unfathomable stores of energy and a really really really long life span where pretty much anything is possible.

Brian

CraigS
27-03-2011, 03:16 PM
Hi Bert;
Thanks for your words. I really do appreciate, read and consider them very carefully, whenever I see them.

Bert, I’m a little confused by this. I’m just trying to understand. Previously you said:


So, just trying to understand, in my own words, given the same starting conditions, we can infer and conclude that life will inevitably occur, but I’m trying to understand what other paths might occur and would we ever recognise the end result as ‘life’ ?

This is tricky !

So, in my own words, physics and chemistry are determinate and predictable, so the process constraints are predictable. However, the ‘end’ result of an unpredictable evolutionary path is unknown (due to lack of data) ... other than it would result in life, which we may, or may not, recognise as life ?

So the same evolutionary process ‘rules’ would apply elsewhere, but the evolutionary paths might differ, because the starting conditions may be the same or different.
So, this was a example of a Complex System ... and from the same rationale, I’m pondering the chances of whether the emergence of life may also follow complex system principles. Interesting !


Haven’t seen Attenborough’s, but I did pour through Mandelbrot’s ‘Colours of Infinity’ (several other books on Chaos, Complexity and Small Worlds).

I think this is the definition of ‘Emergence’ (??)
Simply amazing stuff !
I appreciate your responses.
This is absolutely fascinating !
:)
Cheers & Rgds

CraigS
27-03-2011, 05:06 PM
I suppose so, Brian.
But sceptics would be known as outright 'Deniers' if they didn't flinch to some degree !

I don't think they could hold up against the sheer pent-up tide of humanity and emotion, should such a discovery be confirmed !


Perhaps your mind is less constrained than mine ! :question:

.. "just the facts, m'aam, just the facts ..."
:)
Cheers

Brian W
27-03-2011, 07:20 PM
Sergeant Friday quoted on Iceinspace...gotta love it.

My reality may have been more exposed to things that just don't make sense in the rational world a little more than yours.

One example; there is a graveyard that I once had the right to wander in. It was, and is, a truly culturally historic area. There were many unique headstones which I photographed. There was however one headstone which I was unable to photograph. I tried 4 times and every time the pictures in front of the headstone were fine as were the ones following but the pictures of the headstone were a mass of lines.

I have my beliefs about why no picture turned out but this is not the time nor place for such a discussion.

For myself there is very little difference between saying this world view as supported by this (put in your favourite religious institution) is correct because it is impossible for it to be another way than those who say this is the way it is because of (put in your favourite scientific paradigm) and math or physics or geometry shows that it has to be this way.

I have simply experienced too many things that I cannot explain to believe in a finite set of either questions or answers.
Brian

avandonk
27-03-2011, 09:53 PM
Craig there is no confusion. All I was saying that given the same exact starting conditions, life on Earth would be different. Over ninety nine percent of once living species are extinct.

We mammals only really got going after the dinosaurs were rendered extinct by an asteroid.

As humans are we all that intelligent? I see us being like an ants nest where the individuals follow simple rules and the result is a very complex well organised super organism. We of course follow far more complex rules but the result is the same. I guarantee you that 99% of humans have no clue as to how even all our technology works even at a simple level.
Yet give a twelve year old a modern phone he will find all the features very quickly while a highly educated physicist like me only uses it to make phone calls. Which one of us is smarter?

The take home message is that our ants nest has produced a very complex society where we can follow our individual specialities without knowing how to make the tools to make the tools ...... to make the object we need and use.

Just try and make a $20 pop up toaster from scratch. A metal axe head would be easier. Mine the ore after finding it. Refine the ore to metal etc you get the idea?

It took single cell bacteria over three billion years to explore some of the many possibilities of biological molecular interactions. They 'invented' photosynthesis which uses quantum mechanical tunnelling to transport protons before multicelled organisms developed.

Once multicelled organisms started we then have far more complexity space for them to randomly explore.

Your body is a super organism of many cells following 'simple' rules. Thirty percent of your dry weight is foreign bacteria without which you would die.

All your primal behaviours are programmed by your DNA because of the unbroken chain of your ancestors all the way to single cells that survived and procreated. So you hopefully carry all the 'correct answers' when you are born.

It is all simple really once you realize what is going on. It is fractal layers of complexity all the way down and up!

Bert

CraigS
28-03-2011, 12:13 PM
Bert;
Thanks for clarifying.

'Twas only me who was a little confused .. it takes a while for these things to sink sometimes. :)

Its much clearer now for me.

If found an extremely interesting article which takes me further along in my quest. It is an interview with Stuart Kauffman (http://www.salon.com/news/environment/atoms_eden/2008/11/19/stuart_kauffman/), an American theoretical biologist and complex systems researcher, concerned with the origin of life on Earth.

His life's work has resulted in the perspective that complexity of biological systems and organisms, might result as much from self-organization and "far-from-equilibrium" dynamics, as from Darwinian natural selection.

Bert, you may know of him …

The interview style article poses questions about Complexity, Chaos, Evolution, God, Consciousness, Philosophy and the Emergence of Life.

I am really excited about the research this guy has done, as it encapsulates everything we've been touching on, in this thread.

I think I'm also excited by the fact that it all fits within the fundamental Laws of Physics, whilst stepping beyond the confines imposed by reductionism inherent in the approach of Classical Science.

This article is tremendous, and I fully recommend a thorough read and 'soak' in all that is said.

Its made my day.

Now, Bert don't spoil my fun too much, by telling me this guy is regarded as a Biological Science Outlaw !

(Just kidding).

:)
Cheers

avandonk
28-03-2011, 12:57 PM
He is a god fearing wanker! Another religious idiot posing as an atheist!
Bert

Brian W
28-03-2011, 01:09 PM
Bert, lighten up, just cause some of us do not share your views does not give you the right to be nasty.
Brian

avandonk
28-03-2011, 01:21 PM
OK just for you this man is propounding ideas against his own logic. He invokes a mythical god when he just said there is none. He then goes out to say that Dawkins is totally wrong because he believes in something higher he cannot define. He again is deluded like all religious people are.

I am sorry I was not being nasty just correct.

I am arguing science here not the tooth fairy or the easter bunny or some fictitious god. I am just like all you believers, you do not believe in gods of all the other faiths. I just happen to believe in one god less!

Bert

Brian W
28-03-2011, 01:29 PM
Actually Bert you have no idea of how restrictive or how ecumenical my beliefs may be. You also have no idea of what god or gods I may believe in.

With absolutely no attempt to find out any of the datum required to make a true analysis of my position you simply jump to your own biased, bigoted and unfounded conclusions.

To paraphrase one of my favourite authors; and these are the actions of a scientist!

Brian

avandonk
28-03-2011, 01:31 PM
Brian I really hope so! Bert

CraigS
28-03-2011, 01:42 PM
Actually, I find him invoking 'God' in a very similar sense to Hawking.

I'm pretty sure he's talking down the mythical 'God'. He seems to be attempting to use it, in order to hook into the psyche of the masses he is attempting to reach with his message. He is, after all speaking to a primarily US audience.

Apart from his beliefs, his mainstream research on Complexity in Biological processes, might be an interesting read sometime.

Cheers

avandonk
28-03-2011, 01:57 PM
Please be aware for millenia the 'bit' we did not understand was called GOD. This is a total copout.
We are just as ignorant now as our ancestors when I see drivel about non existent beings seriously considered as real I really worry about the sanity of my fellow humans.

Next time I give a lecture on chemistry or physics I will start off with how god makes it so! In the immortal words of John Makenroe 'YOU HAVE GOT TO BE KIDDING!'

Bert

snas
28-03-2011, 02:39 PM
Craig

Does this thread bring us back around to somewhere that we have been in a previous thread on life? I think I have previously written that I feel that complex exo-life is likely to have numerous similarities to life on Earth. It will need an external source of energy (in our case, food and also oxygen to assist with turning that food into energy). It will therefore require the ability to catch, ingest and digest food and, if it is using oxygen like we do will clearly need some sort of respiratory system. It will need to be able to perceive light and probably also sound, so there will therefore be a need for some sort of visual and auditory system which will also require that it has some sort of central nervous system. because the CNS is a very important part of the life form, it will be encased in some tough material (in our case, a bony skull). And so on it goes.
I'm not saying that either exo-life or a complex life form on earth that started from the same point as we did must be human; just that there would be certain similarities to the complex animal life forms on Earth.

And yet, given the exact same starting condition, life on Earth would be different; yes, I totally agree that humans would be very unlikely to be here, but also feel that the "basic plans" would be here.

Stuart

CraigS
28-03-2011, 03:35 PM
Yes Stuart.

That's also what Bert is saying .. message received and understood !

This model fits well with the principles of deterministic classical physics and chemistry, and Evolution by Natural Selection.

The thing I'm querying however, are the assumptions behind a purely deterministic (and predictable), chemistry and physical environment, like that we think existed on Earth before life got started, and will this always result in life (of some form or another). How much do we rely on inferences within this scenario. What are the inferred bits, and what is known ?

And how complete is our knowledge of those conditions and the processes leading to Emergence ? Are they complex processes, chaotic or purely deterministic ? Is our knowledge complete enough for us to reasonably expect that life will evolve from those same conditions elsewhere ? Is there the possibility of a null (ie: 'no life') outcome, also ? What effect does Chaos/Complexity play in the pre-biotic, primordial environments ? Can we learn anything from this ? What implications does this have on our search for exo-life ? At what scales is the Chaotic/Complexity view of it all relevant ? How might it then influence our thinking ?

The whole modern way of thinking about this, has a lot of empirical evidence coming from physics, chemistry, biology and mathematics. The tools are there to be used, provided we understand how to use them. I don't understand them yet, others do.

Coming back to the theme of this thread, what counter-intuitive aspects might we discover, by thinking more about the chaotic origins of our own beginnings, and then what might emerge when we think about exo-environments ?

Cheers

avandonk
28-03-2011, 03:55 PM
Craig the most complex thing in the Universe is the human brain with over 100 billion neurons and more possibilties of connections than all the atoms in the Universe. Those whales and dolphins have just emailed me and they claim their brains are bigger and more complex and reckon us humans are stupid.

They said something about that they never enslaved their fellow swimmers and would you land people stop killing us and stop stealing our fish!

Bert

CraigS
28-03-2011, 04:11 PM
I wonder what else they think about while they're conscious, Bert ?

:)

Cheers

snas
28-03-2011, 04:11 PM
Craig

What follows is what I FEEL on this subject. I use the word "feel" rather than the stronger word 'believe' because I am not a believing type of person.

Anyway, what I feel:

Given the conditions on Earth at the time that life first arose, I suspect it was perhaps almost inevitable for life to arise. (But, remember, this is just what I feel.) Yet how can I dismiss the "null life" possibility? I cannot. But, given certain conditions such as chemical composition of atmosphere, ocean etc, temperature and whatever extra little, non-supernatural "spark" needed to be added to trigger the change from no life to the origin of life, it was just going to happen. I think Bert has actually said this earlier on.

As for the complex or chaotic system that was the early Earth, and still is today. If you change one or two things slightly it was maybe going to be impossible for life to arise at all or we may well have ended up with completely different life from what we have today. However, I still believe the basic plan of macroscopic life would still be present.

We may have seen the same original progenitor of life appear and stumble along for a billion or two years almost without change (a major problem with asexual reproduction; no exchange of genetic information) but if the asteroid of 65 million years ago had swung by the Earth in a near miss, we may still be small mammals (I think up to the size of a domestic cat was about the largest mammal of 65 million years ago) and hiding from dinosaurs. But who knows; would the dinosaurs have survived the climate changes asociated with the break up of the continents?

Well, it's all very interesting , but we can never know for sure. It's fun to speculate though.:)

Stuart

Karls48
29-03-2011, 10:15 AM
No, they don't enslave their fellow swimmers - they kill them. http://www.jwildlifedis.org/cgi/reprint/38/3/505.pdf

Brian W
29-03-2011, 10:50 AM
Hi all, the above is the type of close minded crap that I have no desire to be associated with. I joined this group for discussions that were honest and interesting but the above is just a bigoted rant from an angry person who does care who he insults or hurts.

I'm out of here.
Brian

CraigS
29-03-2011, 02:47 PM
Yeah .. they're wild, intelligent animals .. same goes for polar bears !

They're certainly not these cuddly, cute things certain people make them out to be !

We're all in a struggle for survival. Humans are also part of the same nature systems as these animals. We are not separate from nature and imposing our wills on it .. we are part of it .. and are imposing our wills on it.

Perhaps our destiny is to destroy ourselves .. just like these dolphin brutes !

bojan
29-03-2011, 03:10 PM
Quite possible...
We evolved in very rough , cut-throat environment, full of predators and prey... and we are both of them. Our basic instinct is one of pack animals..

Recently, we have a situation where our (real) predators are actually gone.. so we must turn against each other (individually and collectively) to discharge the instinct.
Yes, most of those urges are channelised and sublimed by laws, and by substitute activities (sport, business etcetera).. but is this enough to ensure our survival in the long run?
Maybe not...

CraigS
29-03-2011, 03:19 PM
Brian ;
I for one, do not share Bert's style, nor the depth of his emotions on this topic. There is no 'group' here either. There are a bunch of individuals who voice their views in their own different ways.

Bert;
I am aware of your reasons for the position you take, however I also have difficulty when you express, with such aggression, your opinions on sensitive topics. You have grossly offended another individual, and as such, you should take some measures to correct for the impact of your actions.

My greatest concern here, is that this interaction between the two of you, has diminished our abilities to explore tricky topics with due care. I must protest Bert's behaviour on this basis. Whilst Brian could easily have responded in kind, this is not his way, and I have much respect for him, because of it.

The only reason I think we get away with discussing such topics here, I had hoped, is because we try to refrain from going to extremes of emotiveness and expression, and make a genuine attempt to listen to others' views, and not respond from pure bald-faced instinct.

I am very disappointed that this has happened.
:(

Craig

CraigS
29-03-2011, 03:23 PM
Does our survival matter ?
If so, why and to whom ?

bojan
29-03-2011, 03:36 PM
It matters to our genes (or DNA).. because that's what genes do - they multiply and survive (after all, they evolved by this very mechanism) , and they are using us in a process :eyepop:
(not willingly of course.. they just do..)

CraigS
29-03-2011, 03:58 PM
'Tis why I think the best chance for humans moving elsewhere is simple transport of genes, food and water, to elsewhere (panspermia).

This human space travel business seems so far away (in time) and is fraught with some many problems, why not start the easy way ?

(… and who says we haven't already accidentally done this, already ?)

The counterintuitive facts in all this ?
Microbes survive a year and a half in space (http://www.physorg.com/news201938033.html) ..
and ….
Where man boldly goes, bacteria follow -- Are we contaminating space? (http://www.physorg.com/news131259710.html) (this one's an oldie .. but a goodie).
and finally, this …
Battle of the bugs leaves humans as collateral damage (http://www.physorg.com/news195996047.html) ..

Good question and a good paradox for evolutionists ..

Cheers

bojan
29-03-2011, 05:42 PM
If we accept the idea that mutations are random and meaningless/purposeless.. then this is not a paradox at all...

CraigS
29-03-2011, 06:13 PM
Yep .. the circumstances which cause these bacteria to become toxic, may well result in this species being on the well-trodden path towards extinction. However, you could also say that this species has been around for a very, very long time, and has clearly demonstrated its survival capabilities.

Therein lies a paradox .. if its been happy living in a symbiotic relationship with hosts for all that long, why does it still posses the ability to kill itself off in this manner ?

Cheers

bojan
29-03-2011, 06:41 PM
Again there is no paradox here.

You can safely assume that a bad mutation took place... and bacteria with this will not survive.

But, if a good mutation takes place - for example, bacteria multiplies a bit more but doesn't kill the host BEFORE it manages to jump to another one- then this strain will survive (read: that DNA will survive).

No paradox at all.

mjc
30-03-2011, 06:09 AM
A good example, that comes to mind, is the ebola virus (okay not a bacteria - but same evolutionary principles apply). Ebola is too virulent to spread - it's not a very successful virus. Its hosts tend to die faster than new hosts are infected. However, some part or parts of its genome will (probably) be doing very well in other (non-ebola) viruses which do better in spreading and increasing the over all populations. The genes that are common are the genes that prosper.

Even better, some of those genes may have gotten merged with the human genome and doing quite well.

http://www.scientificamerican.com/article.cfm?id=virus-genes-human-genome

Mark C.

snas
30-03-2011, 06:26 AM
Why would Strep pneumoniae start down a path that may kill its host and therefore kill itself? You and I would make a risk assessment and decide that this is a bad thing to do. But bacteria do not have the benefit of foresight. They can only respond to the current stimulus but cannot not know what may happen as a result. The bacteria are not intentionally setting out to kill us, they are simply doing what it takes to survive, even if that may, without them knowing in advance, kill off their host and therefore maybe themselves. Actually, the death of the bacteria is not guaranteed just because the host dies, as long as they have a suitable environment in which to continue.

So Craig, I agree with Bojan that there is no paradox here. Maybe just an unhappy result of a bacterium trying to survive.

Bojan: Are mutations random and meaningless/purposeless? Well, some mutations (many?) are totally random, a simple, accidental error in gene transcription. So we cannot therefore ascribe any foresight of purpose to such a purely random event. Other gene mutations are not so random. At some point in its evolution, Strep pneumoniae developed the genes to allow it to beef up its defences against our immune systems. There is a very small chance that this was a random accident but more likely was a result of it responding to what it was faced with. And clearly this mutation was not purposeless. Not withstanding this, the vast majority of mutations, which I would point out occur in all of us every day, are totally random and many of them are purposeless.

Stuart

bojan
30-03-2011, 07:56 AM
Stuart,
Apart from everything else that you wrote, I disagree with you on the above...
Bacteria can't "developed" genes....
The mechanism of “bacteria response to what it was faced with” is actually this: DNA mutates (randomly and all the time regardless of environment the cause of this are numerous - from instability of DNA multiplication process to ionising radiation), the good (or not harmful enough) changes stay and then they are passed on the next generation. The wrong or bad mutations kill the system (bacteria).
Over time, these "good" or "not bad enough" or just “do nothing” mutations combine into what looks like the "beefing up its defences against our immune systems"… simply because they are passed on to offspring.

My problem here is more your choice of words than actual facts - bacteria doesn't beef up its defences.. it survives because it was just lucky enough that it's predecessors' DNA mutated in such a way that didn't jeopardise the life of it's offspring....

I noticed on many occasions that such kind of approach to public was used to describe the evolution concepts to people.. however I find it misleading (to most of them), because it implies, like here above, some kind of "intentions of genes or bacteria to develop defences".

There was no intention or purpose here, certainly there was no plan.. and the resulting outcome over many generations – despite it may look like from the outside as the gradual "beefing up defences" - is actually a lucky collection/combination of pure accidents.. (do we know how many bacteria died because of bad mutations and the spread of their DNA was blocked? )
Of course, the term "randomness" can be more closely elaborated..
I think it is safe to assume the chances of certain kind of mutations to happen are higher than some others, But I think we can still safely say it is a random process (within some boundaries).
At least, this is how I understand the evolution and it's mechanism.

CraigS
30-03-2011, 08:29 AM
Bojan;
I've gotta laugh … chuckle, chuckle … (not at you, or what you've said, mind you) …

You disagree (in a gentlemanly way) with Stuart's wording and then go onto use use words like 'lucky' and 'jeopardise' …
Both of these words imply 'purpose' … ie: the 'purpose' is survival ! What else is survival, if it is not a purpose ?

And herein is my point, Evolutionists (like Dawkins) use words like 'selfishness' all the time, and yet they argue there is no intent behind anything related to Evolution, (I actually agree with you, & others, on this interpretation).

The paradox which people like Dawkins give us, is that there is a 'blind, unthinking, uncaring, process', which somehow has the intent of surviving, and yet they argue there is no conscious intent !

Hilarious !

Therein lies the paradox !! . And its not with Evolution .. its with those who hold Evolution so closely as to become their belief, that they then impose their own fundamental motivations of existence, (ie: survival), upon the very thing which they argue has no such motivation ! A trap of their own making !

Wryly humourous !
:)
I also have more to say on 'randomness' .. for another post, when I get the time.

Cheers

bojan
30-03-2011, 09:59 AM
Well, it may be my English (as you know it is not my first language) ... but I don't see what you see here ;)

I used those words in quotes, and my intention of doing so was to emphasise the very inaccuracy or inappropriateness of their use.

So let me rephrase:
There is no intent in survival of DNA - this is just a statistical outcome from random process.. which LOOKS or may look like intention (or this word is intentionally used by some people).

CraigS
30-03-2011, 10:06 AM
Yep .. and I agree with you …
:)
My point was about how the Dawkins' of this world use paradoxical language which serves to undermine the whole point .. which is that Evolution has no purpose .. it just happens .. no rhyme or reason (other than those defined by Classical Physics and Chaos/Complexity Theories, and as described by fractal geometry).

I'll have to think about randomness. I don't agree that its purely random, however .. there's more to it than pure randomness.

Cheers

bojan
30-03-2011, 10:17 AM
The only non-random thing that I can understand is that DNA can change in certain direction because of it's inherent chemical properties.
Other changes are impossible or after them DNA is not DNA any more, or the information encoded in it from then on is lethal for the very cell the DNA "lives" in, so it's not passed on any further (again quotes - meaning, DNA doesn't live in a cell.. it is physically there and it processes information as a part of the cell machinery, and that's all.)
The statistical outcome of all this will look like it has certain direction... which may not look like random (as I mentioned earlier, this randomness obviously has certain interval within which the system variables can change).. but it's definitely not intentional.

My feeling is that Dawkins et al sometimes do not do a good service to their ideas. However, I can understand their frustrations.. they are just trying too hard, and most of public simply have nor ability neither training to understand the scientific concepts and principles.

mjc
30-03-2011, 11:25 AM
I think I'm on board with what Bojan has been advocating - particularly with respect to the "no paradox" idea. I agree with Craig with respect to difficulties of language usage. There isn't any selfishness per se - nor any purpose or design - it just the way things tend to happen after the (physical) laws of nature pan out. When a mutation occurs its usually detrimental - sometimes its beneficial. In the case where its beneficial its because of what benefits this change has rather than what this change was "intended" to do that aids in the propagation of a species. But underlying all this is a bunch of genes - of which some are shared widely (between species) and the tendency is that there is a core bunch that do better than others. It doesn't matter what species survives or is demised - the only significant outcome is that some bunch of genes dominate - regardless of what host they contribute to the definition of.

Two observations I'd like to raise:-
1) Randomness - we can go down a dark road on that one, "God does not play dice" etc. But there are events that we cannot predict and the concept of randomness - with the appropriate mathematics works well (Gaussian and Poisson distributions, for example).
2) Life has a tendency to organise - which is counter to the over-all universe's tendency to transition from order to disorder. If I'm correct - you can always find a way of burning things that were alive.

Just some thoughts.

Mark C.

bojan
30-03-2011, 11:44 AM
Yes... apparently life does not obey the laws of thermodynamics...
But, a simple fact that DNA by it's chemical properties tends to self-replicate makes it subject to Darwinian evolution .. self-organising definitely has beneficial effect on DNA multiplication and spread.. and you have the situation where entropy starts to go lower (of course, that means you have to have energy source... in our case, Sun, or sub-water vents or whatever)
I have seem many computer simulations (based on random changes of some parameters of an object that multiplies. and then subject to natural selection) where the outcome in most cases is increase of complexity.. So here you go.
However, since life is a minuscule player in overall energy budget of the Universe.. here and there there may be exceptions to the rule... just like quantum fluctuation...
No paradoxes at all ;)

CraigS
30-03-2011, 11:47 AM
DNA encoding can be altered under certain environmental conditions. This doesn't necessarily compromise the replication and propagation of the DNA.
In some cases though, it may.

Not all influences causing alteration to DNA, necessarily result in non-propagation.

These environmental changes may not be random, also.

Introducing non-randomness in this area results in a non-random process.


Not intentional, (unless human researchers haven't deliberately induced the changes).



Yep. I agree.

Cheers

bojan
30-03-2011, 12:02 PM
Yep..
But imagine this situation:
Let's say, the temperature of the environment has gone up.
This change of the environment will cause DNA more prone to mutation (it is not hard to understand why - atoms are moving more violently at higher temperature and it is easier for some of them to move out from where they were or to create other bonds with neighbours).
Now, the resulting mutation, from the DNA information point of view will have nothing to do with the resistance of the cell to higher temperatures - it may have quite the opposite effect... or the effect can change some totally unrelated property (colour of the cell... or it may grow a horn on one side). And if the temperature stays high and if it is lethal to a cell, it will die.
But, just one in thousand mutations may have right effect - increased resilience to higher temperature.. and cell's offspring survive and multiply further in changed environment.


This is the example of RANDOM mutation(s) of the DNA that resulted in adaptation of the species to a new environment.
No paradoxes....

CraigS
30-03-2011, 01:05 PM
Perhaps so .. but his does not alter the non-random influences and resulting adaptions, which dilute the randomness of the overall process.

I'm open to correction in this aspect .. but don't think there is any purely random process in nature, come to think of it. :question:

When we're talking virtually astronomical numbers, this is an important point.

When we're talking about DNA sequences, we're talking in astronomical quantities, also.

Take a look on SBS Tuesday 5th April (next week), at 8:30pm. There's a documentary on Chaos Theory and Fractals. I'll put a reminder in the Media Forum, shortly.

Cheers

avandonk
30-03-2011, 01:42 PM
It is woolly thinking that starts wars. Mutation of DNA is random. The laws governing the chemistry and physics are not.

The latest research has thrown up a new science called Epigenetics. This is where the environment an organism finds itself in switches off and switches on existing genes in your germ cells ie sperm and eggs.. It is all to do with the methylation of genes making them unreadable.

A simple example of starvation of whole populations due to crop failures caused the children and grandchildren to be smaller and less healthy. Meticulous records in scandinavian countries were the first historical human examples of this. It is even more insidious than this as even extreme stress in times of plenty can cause changes.

Have you ever wondered why we have so much depression in Australia a rich country, when it is almost unheard of amongst the teeming millions in third world countries such as Indonesia. Stress hormones will induce these changes so will pollutants.

Bert

CraigS
30-03-2011, 01:54 PM
How to bridge the gap … and distinguish the domain which exists between randomness and deterministic predictability, without provoking a war .. that is the question .. :question:

Better go and watch the tele next week .. SBS 8:30pm.

Be there ..or be square !
:)

Cheers

avandonk
30-03-2011, 02:11 PM
Here is two pictures. The first a fossil 600 million years old of the earliest multicelled fractal animals called Charnia.

The second a computer graphic reconstruction.

Bert

snas
30-03-2011, 02:39 PM
Bojan, I have to agree that I may have worded that better. You are quite correct, bacteria do not set out to "develop" genes.

Perhaps instead of

"Strep pneumoniae developed the genes to allow it to beef up its defences against our immune systems"

I could have written something more like:

"some Strep pneumoniae developed (by chance, not by intention or plan) the ability to produce a more robust external sugar capsule which gave them the ability to withstand human immune defences"

Still, while the bacteria did not set out to develop the genes, the genes must have developed for some reason. The more robust external capsule would not be present without the genetic information to code for it.

Craig, the "blind, unthinking, uncaring process" has no conscious intent. For example, I did not set out to develop immunity to a certain bacterium or virus, my body just did it as part of it's natural immune responses. (Not really a good example because developing an immune response like that is not an example of evolution, but you get the idea)

So at the "whole organism" level, there is no conscious intent. But at a much smaller level, down at the genes level things happen such as random mutations which may by pure chance happen to confer an increased chance of survival on the organism.

Stuart

bojan
30-03-2011, 02:45 PM
Yep, I am aware of this.. However this is much much "higher level".. way more complicated process than simple DNA mutation I was talking about earlier...
We have to start from somewhere :P

CraigS
30-03-2011, 04:58 PM
Not at all (http://en.wikipedia.org/wiki/DNA#DNA-binding_proteins) …


..more ..


Not random .. induced by the environmental changes which can easily be non-random !

Cheers

bojan
30-03-2011, 05:52 PM
Craig,
I think I disagree... I am afraid that this is all just the free use of metaphorical language to describe processes which are not known in detail (?)
But, I can't really comment any further, because this is beyond my understanding of the subject...
After all, I am just a humble RF electronics engineer, thinking about retirement :P,

CraigS
31-03-2011, 09:35 AM
Ok … found these words … they seem to encapsulate what we've collectively said however, I personally disagree that all genetic mutations are purely random, because there is clear recent evidence to the contrary. This aspect is important when considering the minimal subset of environmental conditions we think are necessary for the emergence of exo-life.

I also find that these words (and the concept), also assumes we know intimately beforehand, what is required for the survival of the organism and then conclude that if an organism survives over the long haul, it must therefore possess the survival characteristics we assumed in the first place.

In Darwin's day, this was obvious at the macro functional/feature level of a species. However, in modern times, we have discovered way more about the complexity of genetic interactions, their influences at the micro (DNA) level and what causes mutations. (Molecular Genetics).

For me, a large proportion of the diversity we see amongst life-forms, may be more a characteristic of not necessarily survival associated, but none-the-less, environmentally induced mutations. Perhaps its my own lack of knowledge, but I'm not sure Darwinian Evolution Theory addresses the reasons for propagation of what could easily be mutationally induced, non-essential characteristics (??) :question:

As a result, I feel that there are other processes which run in parallel, (ie: not necessarily contrary to Darwinian Evolution), which have clearly operated since life emerged from the chaos.

What does this perspective tell us about the chances of life emerging elsewhere ? Frankly, I have no supportable ideas, other than I can see this thinking does support the concept that diversity, (which includes the superset encompassing the 'null' no-life outcome), may be way more susceptible to the initial environmental conditions from which life originally emerged once, than perhaps we can envisage. It also lends legitimacy to the possibility of extreme rarity of more than once instance of it.

There is a Hypothesis called 'Differential Susceptibility' which speculates that individuals vary in the degree they are affected by experiences, or qualities of the environment they are exposed to. These characteristics are then linked to susceptibility factors which can range from emotional states like temperamental anxiousness all the way 'down' to the protein/DNA level. (Mind you, it remains as a 'considered' hypothesis ;) ).

Having made these statements, I find that the following words, do fairly describe the classical biological definitions pertaining to the role randomness plays in classical, traditional, Darwinian Evolution Theory:



Cheers

CraigS
02-04-2011, 07:03 AM
Hi Mark;

Have a look into Chaos Theory in particular, the emergence of self-organisation.
It really is truly fascinating !

Cheers