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** STICKY ** Science, layman and language

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** STICKY ** Science, layman and language
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FaithlessThinkerUser avatarPosts: 618Joined: Wed Apr 07, 2010 10:41 am Gender: Cake

Post ** STICKY ** Science, layman and language

I was planning to post something similar earlier but scrapped the idea. Now I got re-inspired by AndromedasWake's video about fine-tuning.

Let us all put together from our knowledge a list of terms that are commonly misunderstood by creationists, theists and regular people as opposed to the scientific community. Please include for each term:
  • How it is misunderstood by laymen.
  • What it actually means in science.
  • An easy definition for a regular person to correctly understand it.
  • And if possible, some examples and media.
The first one ought to be the inspiration behind this topic: "fine-tuning," and who is better qualified to talk about it than AndromedasWake!

I will add another term when I'm prepared to do so. I have a few terms in mind, but can't recall right now. Also need to do some research.

This is my first time asking to sticky a post. If we have enough terms listed, I think it will be worthy being stickied as a reference.
It was my honest attempt to find a more pure form of God that made me realise that there was none.”
— Master_Ghost_Knight
Previously known as anon1986sing. You can call me FT. :)
Thu Aug 12, 2010 12:40 am
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lrkunUser avatarPosts: 3831Joined: Wed Jun 23, 2010 8:37 pmLocation: R. Gender: Tree

Post Re: Sticky please: Science, layman and language

Is it okay if we start by posting a term commonly misinterpreted by the general public?

Ex. The term Theory in science is different from the term theory as used in a general sense.

Then maybe someone can come up with the other steps?
Unsupport unthink.
Thu Aug 12, 2010 2:22 am
TylzenUser avatarPosts: 156Joined: Wed Oct 21, 2009 4:58 pmLocation: Denmark Gender: Cake

Post Re: Sticky please: Science, layman and language

Big Bang, was not actually an explosion.
It can drive me nuts, and of course the "It is just a theory" argument, which is so fallacious that it kills kittens every time it is spoken.
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Thu Aug 12, 2010 6:51 am
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FaithlessThinkerUser avatarPosts: 618Joined: Wed Apr 07, 2010 10:41 am Gender: Cake

Post Re: Sticky please: Science, layman and language

lrkun wrote:Is it okay if we start by posting a term commonly misinterpreted by the general public?

Sure! That's also something I mean when I say "misunderstood." :)
It was my honest attempt to find a more pure form of God that made me realise that there was none.”
— Master_Ghost_Knight
Previously known as anon1986sing. You can call me FT. :)
Thu Aug 12, 2010 10:44 am
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AndromedasWakeAdministratorUser avatarPosts: 598Joined: Fri Feb 20, 2009 11:38 pmLocation: Captain's Chair, League HQ Gender: Cake

Post Re: Sticky please: Science, layman and language

Fine-Tuning


In physics, fine tuning is an undesirable consequence of being unable to explain variables which must be precisely set to make the model accurately describe the observable Universe. When something has to be finely tuned by a physicist, the immediate question is, "why should that be exactly right?"

If the physicist has an answer, then there is no fine tuning problem, because the mechanism for the given outcome has been established. Out-standing fine tuning problems indicate which parts of a particular model need work. Fine tuning is not the same as the speculative term "fine tuned Universe". This term is used to discuss the extent to which seemingly fundamental parameters in nature must take very precise values in order for us to be here. For example, in the standard model of particle physics, there are several values which, if changed even a tiny amount, would forbid any kind of higher chemistry to take place. Because fine tuning is a classical term which describes the action of a physicist (i.e. a person) the term "fine tuned Universe" has unwelcome connotations.

Linguistically speaking, it may imply that a person has set the natural laws which govern the Universe, and so is often used underhandedly by apologists such as William Lane Craig. He has used the phrase "the fine tuning of the Universe" thus merging "fine tuning" and "fine tuned Universe" together. The former describes intelligent action by its definition, the latter is an unfortunate overlap that would be better replaced with the word "precision" to avoid confusion. On pragmatic grounds, scientists must assume the precise values are a physical necessity if they are to uncover the process which relates them. William Lane Craig dismisses this on the basis that the values are "just arbitrary". This is where he exposes his inability to distinguish a model (a map) from reality. These values are arbitrary in their respective models, which is why they represent fine tuning problems. Thus they are also indicators of the incompleteness of their respective models. The apologist's perspective is that the models must already be 100% accurate, meaning out-standing fine tuning problems indicate a fine tuning of reality. No scientist puts so much faith into the current state of physics! :lol:

Singularity


Not to be confused with technological singularity. In mathematics, a singularity is a region of undefined solutions from a given equation or function. If you've ever plotted a function on a graph to see an asymptote, you are looking at the region close to a singularity in that function. For example, the function f(x)=1/x approaches singularities as x approaches 0. When x=0, the solution f(x) is undefined (commonly called infinity, but that isn't a real solution.)

In physics, specifically the General Theory of Relativity, there are similar instances called gravitational singularities. Two types are known; black hole singularities and the big bang singularity. Hopefully I don't need to go into too much detail here, but simply refer to the example above. These singularities are not themselves objects - they do not have any physical meaning whatsoever. It is as relevant to say the Universe was an infinitely dense, infinitely small point, as it is to say it was a cat, a proximity mine, and an accident waiting to happen. There is simply no physical meaning in the term singularity when used to describe the state of the real Universe. A black hole, which appears as a singularity in GR, almost certainly harbours a quasi-singular (incredibly dense) corpse of a star with a real volume.

A singularity, like a fine tuning problem, is an indication that a model is incomplete, or not sufficient to give a complete description of a system on its own. GR approaches a singularity in two real instances, black holes and the big bang, so in order to fully understand those things, we need to extend GR. Considering that singularities occur when a dead star, or the whole Universe, is volumetrically small, it makes sense to look to quantum mechanics for a more complete description. QM has already proved invaluable at describing the other fundamental forces at small scales (i.e. field theory) and a quantum field theory of gravity would be the next logical step. Such a thing is not easy to obtain though, because gravity is not like the other forces (it's much weaker, it has one charge and we can't escape the accuracy of GR in predicting things like gravitational lensing.)

An extended theory of gravity may remove singularities altogether, or put them somewhere else. Only time will tell. It is expected from quantum mechanics however, that "real singularities" cannot exist.

More to come when I find the time. ;)
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Thu Aug 12, 2010 11:16 am
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RichardMNixonUser avatarPosts: 1047Joined: Thu Jul 30, 2009 8:45 pmLocation: USA Gender: Pinecone

Post Re: ** STICKY ** Science, layman and language

Evolution: the change in the inherited traits of a population of organisms through successive generations. ~ Wikipedia

Quantum physics: a branch of physics providing a mathematical description of much of the dual particle-like and wave-like behavior and interactions of energy and matter. ~ Wiki

Homeopathy: :roll: see Water.

There's nothing magical about any of these.
"When I come to my own beliefs, I find myself quite unable to discern any purpose in the universe, and still more unable to wish to discern one." ~ Bertrand Russell
"If we do not succeed, we run the risk of failure." ~ Dan Quayle
Thu Aug 12, 2010 2:34 pm
JessePosts: 1Joined: Thu Aug 12, 2010 3:15 pmLocation: Calgary, Alberta, Canada Gender: Male

Post Re: ** STICKY ** Science, layman and language

The term BY DEFINITION is more a mathematical term than a scientific one, but I hear it used for rhetorical purposes all the time. Theists will often say 'god is, by definition, the thing that necessarily exists' without realizing that there are are at least two fundamental problems with doing so. The term is supposed to be used to indicate that a thing with a certain set of properties satisfies a definition (itself a list of properties). It is naive to think that one can merely add existence to the definition of a thing - and all of a sudden 'by definition' it exists. It's not a magic spell. And if you say something 'necessarily' exists, it does not mean that it actually exists, but that it's defined as a 'necessary being' which still has to be found in the world of things. Definitions only make clear what it is we are looking for.
Thu Aug 12, 2010 3:48 pm
negativepositivePosts: 1Joined: Thu Aug 12, 2010 4:05 pm Gender: Male

Post Re: ** STICKY ** Science, layman and language

One that bugs me, which is not necessarily a science topic, but rather one of argumentation, is how many of them think the definition of "fallacy" is JUST something that it incorrect or that "fallacy" is a simple synonym for "lie," rather than an argument based on flawed inference.
Thu Aug 12, 2010 4:16 pm
AndromedasWakeAdministratorUser avatarPosts: 598Joined: Fri Feb 20, 2009 11:38 pmLocation: Captain's Chair, League HQ Gender: Cake

Post Re: Sticky please: Science, layman and language

Entropy and the 2nd Law


Entropy is something that some people, even some physicists I've met, find horribly confusing. I suspect the problem is down to the two possible interpretations of the term, depending on whether you use Thermodynamics or Statistical Mechanics. We'll start with the latter, because that's where one of the major errors comes in.

In Statistical Mechanics, a system is described in terms of the probabilities of its components having certain configurations or states. The simplest system to consider is just some ensemble of atoms in a gas. You can set them off in a nice orderly state, at even distances to one another in a lattice. Over time, the atoms will fly around in random directions, interacting when they get close enough and "bouncing" off each other. Provided that the state variables like pressure/volume and temperature have been accounted for, you can make an even assessment of the probability of each atom having a given position and velocity. The prime state, in which the atoms were all uniformly positioned and had no velocity would be considered the least "entropic" state, because there is only one arrangement like it. However there are immeasurable configurations in which the atoms are flying about, making any such state highly entropic.

This is where the idea of order and disorder comes from. Imagine a glass. It begins in the least entropic arrangement, but if dropped it will smash and there are numerous outcomes which are similar to each other, but nothing like the original state. Once the glass is in one of the more likely states, it has gained entropy. It's easy to see from examples like this why people consider higher entropy as being more disorder, but what is statistically disordered might be something we humans consider to be orderly.

Another analogy would be the energy distribution at the Hubble scale (about 70Mpc, i.e. the transition to homogeneity). In the early Universe, energy was very smoothly distributed with only minor fluctuations, like a clean sheet of paper. Over time, the Universe has become lumpy, like screwing/crumpling up paper, with mass-energy (Baryonic/Dark) becoming concentrated in a web with huge voids. This lumpy/screwed up configuration could be slightly different, but still be lumpy/screwed up. However, only one state exists where the energy/paper is perfectly smooth, and only a few where it is slightly less than perfectly smooth. So whilst galaxies might look ordered, the large structure they belong to is highly entropic. This is why order/disorder can be a bad way to describe entropy.

This statistical interpretation basically tells us the number of possible configurations, and as things become more "disordered" that number should rise. Ergo entropy always goes up.

I'm sure you recognise this as the second law of thermodynamics, but what is entropy in thermodynamics? Well, it's nothing more than a measure of unusable energy in a thermodynamic system. Such systems will always act to reach equilibrium, and achieve maximum entropy. At this point, the system can no longer perform work (transfer energy) because all the usable energy is gone. The most familiar analogy is that of a cup of tea left on a table. The room/tea system is not in equilibrium, and the temperature of the tea (characterised by the kinetic energy of its tea molecules) enables it to perform work on the room by slightly warming it. As it does so, the tea becomes less and less able to perform work, because it has less and less energy for doing so. The entropy of the whole system increases until the tea and room are at the same temperature, at which point the entropy is at maximum.

If the room were to reheat the tea by giving it some of its energy, this would result in a decrease in system entropy which is forbidden by the second law. This might seem mundane, but its fundamentally important to the Universe that this process has a definite direction, because this is the direction of the arrow of time.

At very small scales and short time-scales, physics "looks" the same forwards as it does backwards. As such, there is no reason why it should have to go in one direction, but at macroscopic scales (approximately the Avagadro scale of 10^23 atoms) time ceases to be symmetrical. The second law of thermodynamics forcefully violates this symmetry (known as Time- or T-Symmetry) such that physics no longer works both ways. Having fragments of an egg fly together and jump off the floor would require entirely different physics to those which cause it to fall and smash. Some say entropy gives us the direction of time, others say the direction of time gives us entropy. Whichever it is, the two are very tightly coupled.

Entropy and the second law are often misused in two major ways. The first is the simple error in equating statistical disorder with decay, and suggesting that beautiful, complex organisms are more ordered and thus violate the second law. Obviously, these systems undergo a remarkable variety of processes, but let's just assume that evolution requires atoms to perform work, and they should have run out of usable energy. The problem with this kind of argument is that entropy only has to increase in an isolated system, and the Earth isn't isolated. The Sun performs work on the Earth, giving us lots of usable energy. Yes, the Sun is losing its usable energy but it has a lot to spare, at least for a few more billion years.

At this point I should note that there is no consensus on whether the concept of entropy can be applied to the Universe as a whole, because there is no clear description of the Universe as a system. This is sort of related to the second misuse of the second law, which is to try and prove that the Universe must be finite in age. If entropy always increases, wouldn't it have reached its maximum by now in an eternal Universe?

The answer is... huh? We start around the time of the Big Bang, a distinct change in state for our Universe. At this time, crudely speaking it has low entropy. What's to stop some other unknown process from setting low entropy? What's to stop a process which flips the arrow of time? If T-symmetry is coupled to other major symmetries (such as Charge and Parity) we'd need to figure out what happens with CP-violation to even begin to use entropy at this time. It sounds speculative, because it is. There is simply no way of knowing with current physics how the initial state of the Universe came to be the way it was, and using it to make an argument is like sticking your fingers in your ears and yelling "I DON'T WANT TO WORK OUT ANY MORE!"

Ironically, those who invoke the second law in this way seem to completely ignore the first, which is that very famous energy conservation law. To those people, this is as blunt as I can make it: The second law of thermodynamics is no more proof of a temporally finite Universe than the first law is proof of an eternal one.
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(( "We are 'star-stuff'. We are a way for the cosmos to know itself." - Carl Sagan | Music! | Twitter - [ AndromedasWake | SiriusStargazer ] ))
Thu Aug 12, 2010 5:14 pm
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TheFlyingBastardUser avatarPosts: 787Joined: Wed Jun 30, 2010 3:17 am Gender: Male

Post Re: ** STICKY ** Science, layman and language

I'm a complete and utter physics newbie, and though I understand how energy works (that if there is never any energy added to a system, the energy in the system will eventually cause the system to become "stable"), but I still don't understand the difference between entropy and disorder.

If tea would warm the room ever so slightly and eventually there would be no more energy to expend, causing a certain "balance", how does that mean that there's "maximum entropy"? That term sounds (but only intuitively) like the exact opposite of there being no energy that flows around.

Perhaps this stems from an incorrect understanding of what entropy is, but could you give me another example that shows the difference between entropy and disorder, in Sesame Street language?
Thu Aug 12, 2010 5:40 pm
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AndromedasWakeAdministratorUser avatarPosts: 598Joined: Fri Feb 20, 2009 11:38 pmLocation: Captain's Chair, League HQ Gender: Cake

Post Re: ** STICKY ** Science, layman and language

TheFlyingBastard wrote:If tea would warm the room ever so slightly and eventually there would be no more energy to expend, causing a certain "balance", how does that mean that there's "maximum entropy"? That term sounds (but only intuitively) like the exact opposite of there being no energy that flows around.


The reason is because the system is in equilibrium once the tea and room are the same temperature. Because the tea/room will not just spontaneously start heating the other after they've reached this state, we can say that there is no more usable energy left in the system. The usable energy was present in the tea when it was warmer than the room, and it gradually expended it by warming the room a tiny bit, cooling itself in the processes. All of that usable energy has thus become unusable in the process, because it is not reversible. That energy would still be usable if it were possible for the room to expend the same amount of energy and reheat the tea, but this process doesn't occur naturally. Therefore, since the usable energy at the start of the process has all now become unusable, and entropy is a measure of the unusable energy, the entropy has reached its maximum. In order to reheat the tea I must perform work on it, but I'm external to the system. Each time I do this, I'll give the system more energy to use and it will keep using it up, continuously increasing the entropy.

Regarding entropy and disorder, this comes from the statistical treatment, where entropy gives us a measure of the uncertainty of a system being in a particular state. A sheet of paper* which is completely flat is 100% certainly flat. There is only one way it can be completely flat, so my certainty is 100% and my uncertainty is 0%. There are two ways I could fold it in two, along the long or short axis. Therefore, if I know the paper has one fold, I can only be 50% certain as to which way it has been folded. The number of potential states has increased from one to two. This increase in uncertainty is an increase in entropy. If someone screwed up the paper so it had 50 folds and no longer looked rectangular, I could hardly be certain as to what state it was currently in, because there are trillions of ways I could make 50 arbitrary folds in a paper and distort its shape. So the more scrumpled the paper becomes, the more entropic its state becomes.

In a natural example, say a collection of atoms zipping about, there will be a tendency to adopt states like this, ones which are not ordered in a way which limits their probability. But the reason entropy and disorder are not perfectly equivalent is because the word disorder is a generally negative term meaning mess or chaos to most people. A snow flake is highly entropic, but is it disorderly? Statistically yes, but what would most people say? I reckon most would say a snow flake is a very ordered arrangement of water, because it looks nice. Creationists think galaxies and people look nice, and so do I, but they then conclude that galaxies and people are statistically orderly (like uncrumpled paper) but they aren't. You are a very disordered arrangement of your atoms. So equating entropy and order as we commonly use the word leads to fallacious reasoning.

*Obviously in the paper example I can just look at it, so I don't need to use Statistical Mechanics to predict the state of the paper, but it's used to predict the behaviour of an ensemble of atoms, which we can't just look at. Therefore we have to make some probabilistic assessment of the state of the atoms, informed by the laws which govern them.
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(( "We are 'star-stuff'. We are a way for the cosmos to know itself." - Carl Sagan | Music! | Twitter - [ AndromedasWake | SiriusStargazer ] ))
Thu Aug 12, 2010 5:57 pm
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MokyUser avatarPosts: 175Joined: Tue Feb 24, 2009 4:41 am Gender: Female

Post Re: ** STICKY ** Science, layman and language

Micro evolution - Small changes in time that don't actually change a species.
Macro evolution - Species evolving and new species coming about as a result of evolution.

They are basically the same things, but creationists kind of cherry picked micro evolution because they can't provide evidence against it, so they accept it, but then they turn around and say that these small changes don't lead to large changes that separate species. I'm sure a biologist here can better explain this because I heard these terms only a handful of times.
Thu Aug 12, 2010 6:01 pm
TheFlyingBastardUser avatarPosts: 787Joined: Wed Jun 30, 2010 3:17 am Gender: Male

Post Re: ** STICKY ** Science, layman and language

AndromedasWake wrote:Therefore, since the usable energy at the start of the process has all now become unusable, and entropy is a measure of the unusable energy, the entropy has reached its maximum.

Aaaand that was the click I needed for the law of thermodynamics.

So what you're saying basically is that people are confusing the kind of entropy that means there's no more usable energy left with...

AndromedasWake wrote:I reckon most would say a snow flake is a very ordered arrangement of water, because it looks nice. Creationists think galaxies and people look nice, and so do I, but they then conclude that galaxies and people are statistically orderly (like uncrumpled paper) but they aren't. You are a very disordered arrangement of your atoms. So equating entropy and order as we commonly use the word leads to fallacious reasoning.


...the kind that leaves socks somewhere in the gutter because stuff can go anywhere wherever it damn well pleases. (In the case of a snowflake, there are a billion shapes a snowflake could have, but in this case it just happened to have this form.)

Am I getting warmer closer to understanding it?
Thu Aug 12, 2010 6:21 pm
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RichardMNixonUser avatarPosts: 1047Joined: Thu Jul 30, 2009 8:45 pmLocation: USA Gender: Pinecone

Post Re: ** STICKY ** Science, layman and language

AndromedasWake wrote:A snow flake is highly entropic, but is it disorderly? Statistically yes

Be careful with this, by my understanding a snow flake does have less entropy than the liquid water that formed it. Freezing is exothermic, so it's the entropy term of the Gibbs energy that stops it from being spontaneous at higher temperatures. The formation of a snow flake in a closed system of air and water is of course entropically favorable but I think this is because the air gains more entropy than the water loses. But in an open system considering only the water, which is all that I imagine a layman would consider, I believe the entropy does go down by 22 J/mol-K - the entropy of fusion.


...the kind that leaves socks somewhere in the gutter because stuff can go anywhere wherever it damn well pleases

My professors like to use the example of every air molecule in the room suddenly flying into a dense cluster in the right-hand corner. This would be like throwing a handful of ping pong balls at the ceiling and having them land stacked in a column. You could try it until the end of time and it would never happen.

When you're counting states, states that are equivalent in energy, "degenerate," are counted as the same. 10 ping pong balls on the floor have 0 gravitational potential energy and ~0 kinetic energy if they're all going in different directions. There are many possible ways you can arrange them to get 0 energy. Stacking them in a column would give some of them gravitational potential energy making it a nondegenerate state and counting it separately. There are much fewer possible states with gravitational potential energy so it is higher in entropy.

That's where the two entropies are connected - states with useful energy are entropically unfavorable, so they'll eventually transition into states with no useful energy.
"When I come to my own beliefs, I find myself quite unable to discern any purpose in the universe, and still more unable to wish to discern one." ~ Bertrand Russell
"If we do not succeed, we run the risk of failure." ~ Dan Quayle
Thu Aug 12, 2010 7:06 pm
BiggiePosts: 1Joined: Thu Aug 12, 2010 7:33 pm Gender: Male

Post Re: ** STICKY ** Science, layman and language

League of Reason - A scientific term that is commonly misunderstood by laymen to mean a group of people with actual philosophical insight and intellectual and academic integrity. The origin of this misunderstanding spouts primarily from the North American definition of "reason(able)" which usually is used to denote things which are considered proven to be rational and logically sound. This moniker is actually misleading considering that almost every time a philosophical question is asked of them they (especially the user known as Thunderf00t) go into a logical fallacy frenzy. What the laymen must understand is that while these men are very intelligent, hold a great deal of scientific knowledge, and reach very reasonable conclusions, that does not mean that they are actually 100% intellectually honest. What they say must be closely and skeptically examined, especially when the conversation strays one iota away from a scientific topic.

Another misunderstanding that comes from this moniker is a almost zealot-like faith in the scientific method to produce accurate results. While the scientific method is certainly the greatest triumph of intelligence for our species, it does not hold a monopoly on truth. In fact, the scientific method itself refutes such a claim. To believe that one knows something with absolute certainty is intellectually dishonest irrational. Science is a methodology that helps us (as TF00t said) "build models of utility." This does not mean that the theories that are built from our scientific pursuits are accurate. Science will always be a work in progress, it must always self-scrutinize and self-correct. We must never hold something to be absolutely true because we have good evidence to believe it to be so. We must keep open and skeptical minds at all times, while always taking the most reasonable path. We are naked apes in the dark, barely able to open our feeble and pathetic eyes, we just started to be able to accurately understand and predict the world around us, much less control it, and some people would have you believe that we hold absolute knowledge on most of the questions asked by us sentient apes.

What a fucking joke in my opinion.

I hope this clears some misunderstandings up.


-Biggie Smalls

"The demand for certainty is one which is natural to man, but is nevertheless an intellectual vice. " -Bertrand Russell

"The whole problem with the world is that fools and fanatics are always so certain of themselves, and wiser people so full of doubts." -Bertrand Russell
Thu Aug 12, 2010 7:34 pm
TheFlyingBastardUser avatarPosts: 787Joined: Wed Jun 30, 2010 3:17 am Gender: Male

Post Re: ** STICKY ** Science, layman and language

RichardMNixon wrote:When you're counting states, states that are equivalent in energy, "degenerate," are counted as the same. 10 ping pong balls on the floor have 0 gravitational potential energy and ~0 kinetic energy if they're all going in different directions. There are many possible ways you can arrange them to get 0 energy. Stacking them in a column would give some of them gravitational potential energy making it a nondegenerate state and counting it separately. There are much fewer possible states with gravitational potential energy so it is higher in entropy.


You use big words.
Big words that are totally lost on me.
I should read a book on this subject.
Thu Aug 12, 2010 8:09 pm
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hackenslashLime TordUser avatarPosts: 2376Joined: Mon Feb 23, 2009 3:43 pm Gender: Cake

Post Re: ** STICKY ** Science, layman and language

Moky wrote:Micro evolution - Small changes in time that don't actually change a species.
Macro evolution - Species evolving and new species coming about as a result of evolution.

They are basically the same things, but creationists kind of cherry picked micro evolution because they can't provide evidence against it, so they accept it, but then they turn around and say that these small changes don't lead to large changes that separate species. I'm sure a biologist here can better explain this because I heard these terms only a handful of times.


That's pretty good, but not entirely rigorous.

Evolution is defined as the change in frequencies of alleles. An allele is a particular version of a gene. When defined in this way, micrevolution is changes in allele frequencies in a population, or below species level. Macroevolution is changes in allele frequencies at or above species level. This can indeed include speciation, as you suggest, but that isn't the whole picture. Another type of macroevolutionary event is extinction, because in that scenario, alleles at species level go from 'some' to 'none' which is a change in allele frequencies at or above species level.

Of course, there is one scenarion in which an extinction event constitutes a speciation event simultaneously. Where you have a ring species, the entire ring is defined as one species under the Biological Species Concept (BSC), becase under that definition of species, which is the most broadly accepted definition in the relevant scientific circles, a species is 'a population throughout which gene flow occurs'. In the case of a ring species, there is a continuous chain of gene flow, but at either end you have outliers of the species for which the interchange of genes is not possible, but they are still the same species. If, for example, there was an event wiping out a portion of the middle of the ring, meaning that gene flow is interrupted, you have a speciation event, thus a speciation event caused by extinction.

Edit: @ AW, that's a beautiful deconstruction of entropy there. I have been planning an essay on that very topic, and you have completely taken the wind out of my sails. Good work.
Thu Aug 12, 2010 8:12 pm
MokyUser avatarPosts: 175Joined: Tue Feb 24, 2009 4:41 am Gender: Female

Post Re: ** STICKY ** Science, layman and language

@hackenslash I kinda felt it would be wrong for me to try and go into detail because the last time I learned anything biology related was a small segment on biochemistry for Forensic Science ^^'
Thu Aug 12, 2010 10:22 pm
RichardMNixonUser avatarPosts: 1047Joined: Thu Jul 30, 2009 8:45 pmLocation: USA Gender: Pinecone

Post Re: ** STICKY ** Science, layman and language

TheFlyingBastard wrote:
RichardMNixon wrote:When you're counting states, states that are equivalent in energy, "degenerate," are counted as the same. 10 ping pong balls on the floor have 0 gravitational potential energy and ~0 kinetic energy if they're all going in different directions. There are many possible ways you can arrange them to get 0 energy. Stacking them in a column would give some of them gravitational potential energy making it a nondegenerate state and counting it separately. There are much fewer possible states with gravitational potential energy so it is higher in entropy.


You use big words.
Big words that are totally lost on me.
I should read a book on this subject.


Sorry :oops: I have to teach this junk next month, I should probably figure out how... :|

Think of hot coffee in a cold room. Nature hates macroscopic gradients - it likes everything nice and uniform. Hot or cold things go to room temperature to eliminate temperature gradients, concentrated blobs of food coloring in water spread out to eliminate concentration gradients, air flows out of a balloon to eliminate pressure gradients.

Take a cup of water with a drop of food coloring in it. The food coloring is it's own molecule, different from the water. We'll say our cup is microscopic and there are 5 molecules of food coloring in 25 molecules of water. If all the color molecules stay precisely were you dropped them, there's only so many ways they can be arranged, only so many ways you can fit the puzzle pieces together. If the color molecules are dispersed throughout the water, there are many more ways you can assemble the color molecule-water molecule puzzle. Those additional states are what make the dispersion favorable. A glass of uniformly red water may appear more "ordered" than a wispy pattern like this:
Image, but at the micro-level, the red water has more entropy because there are more possible ways the same system could exist - more ways you could assemble the puzzle. You can even try it, lets use a grid with 5 rows and six columns. When you add the color, it's only in the first row. Here's the combinations, there's only six:

C C C C C W _ | C C C C W C _ | ... | W C C C C C |
W W W W W W | W W W W W W | ... |W W W W W W|
W W W W W W | W W W W W W | ... |W W W W W W|
W W W W W W | W W W W W W | ... |W W W W W W|
W W W W W W | W W W W W W | ... |W W W W W W|

(Cs are smaller textually than Ws, ugh)

Now consider how many combinations you could make if you could put the colors in any row. It's important to remember that every H2O molecule is exactly the same. You couldn't make a seventh state out of those above just by switching two waters; it would identical. The only way to increase the number of states is to mix the Cs into the lower rows. If the color is spread out and uniform, even if that seems more "ordered," it has more entropy.

The second law really comes into play when you consider the prospect of going backwards. Ever seen someone suck food coloring out of water? :lol:
"When I come to my own beliefs, I find myself quite unable to discern any purpose in the universe, and still more unable to wish to discern one." ~ Bertrand Russell
"If we do not succeed, we run the risk of failure." ~ Dan Quayle
Thu Aug 12, 2010 10:46 pm
Anachronous RexLeague LegendUser avatarPosts: 2008Joined: Mon Jun 07, 2010 4:07 pmLocation: Kansas City, MO Gender: Male

Post Re: ** STICKY ** Science, layman and language

I would point to the misconception that evolution denotes improvement by standards we judge to be good. That a species, for instance, cannot evolve to be smaller, weaker, or stupider. When, if fact, all that evolution by means of natural selection requires is that a species be better suited to its environment. If a species spends a great deal of energy maintaining a large brain in an environment where food is scarce but does not require a great deal of intelligence to acquire, having a smaller brain might actually be of great benefit. The same could be said of size and muscle mass.

It is probably the case that this falls under a broad category of misconceptions about evolution, but it is nonetheless annoying.

As for examples... well you run into it quite often, but the most recent time that comes to mind was Truthful Christian in the Leagues last show.
Our prefrontal lobes are too small. Much too small. That's a problem of the birth canal, I'm very sorry to say for those that like their birth canals... tight.
-C. Hitchens.
Thu Aug 12, 2010 11:09 pm
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