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Science's 125 Big Questions
Shadow Wrought writes "To celebrate their 125th anniversary Science is running a series of articles on the 125 Questions of Science. The top 25 each link to an article exploring the subject of the question in depth. Included are such questions as: Are we alone in the Universe? What are the limits of conventional computing? How did cooperative behavior evolve?"
Are we alone in the Universe? What are the limits of conventional computing? Why I can't I get a date?
We already know the answer to the ONE question... What we REALLY need to do is build a machine to figure out what that question is - who's with me?!
Really? I'd think swapping them round might be a good idea. I won't comment on the ordering of biology vs physics though, as it's hard to fairly rank the two.
A preditor/parasite found that it's easier to keep eating if it doesn't kill off it's host completely. Small steps from there could make it benign to it's host; and further small steps can make it cooperative.
42 * 2.9761904761904761904761904761905 == 125 Coincidence? I think not!
through one of his prophets Niven - "The perversity of the universe tends towards a maximum"
Have you been touched by his noodly appendage?
Given this average height, toast doesn't have time rotate more than half a turn before hitting the ground. If tables and people were something like 10 feet tall, then people would be wondering why toast allways falls with the butter side up.
Well, the 10 feet figure is made up but that's the basic idea from the article.
Generally answers seem to cluster around the idea of kinship and the furthering of an individuals gene pool.Perhaps the answer will come in tandem with the solution to another evolutionary riddle pertaining to our kind, why is it we have such relatively small canines? The males of most primate species have large canines especially for fighting, usually other males in order to win controll of groups of females. Some speculation has it that monogamy in our kind did away with the need for large canines, or maybe, in our kind females did away with the male perrogative of controlling breeding?
!Happy Birthday Canada!
"Academicians are more likely to share each other's toothbrush than each other's nomenclature."
Cohen
Or to put it another way: Why does the entropy of any closed system always increase? Why do we take the 'causal' solution to Maxwell's equations when determining the field generated by an accelerating charge? Why does the evolution of a quantum system appear to involve an irreversible step - wavefunction collapse? These may in fact be the same question in different guises. I think it's the number one question in physics. Every fundamental law of physics has time reversal symmetry (or at least CPT symmetry) and 'future' and 'past' look as similar as 'left' and 'right' at a fundamental level. So the arrow of time we see so blatantly around us is in serious need of explanation. It's almost as if physicists live in denial about the fact that their fundamental theories clearly just don't seem to match up with reality. But there are some good books on the subject such as Zeh's.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
I'm sorry, for a second there, I thought your post included the phrase "the rotational speed of toast".
My Bad.
No folly is more costly than the folly of intolerant idealism. - Winston Churchill
More than half of the top 25 were biology questions. You'd think physics would be a little more strongly represented. But I'm all for answering the evolution questions if it'll stop my in-laws from giving me creationist literature.
The article on why humans have so few genes does some nice hand-waving but fails to answer the core question. Sure, the genome can do some interesting combinatoric stuff to get more out of a given length of DNA, but that does not answer the question -- why should humans have fewer genes than something so simple as a mustard plant or rice?
I suspect the answer is related to human (mammalian) mobility and thermoregulation. If a rice plant gets stuck in a hot place, all it can do is use a different part of its genome to make proteins suited for hotter weather. In contrast, people can move out of the sun while their body basically maintains a constant temperature. Similarly if the plant faces too much cold, too much water, too little water, to much sun, too little sun, too much salt, etc. it can do nothing but sit there and hopefully pull something out of its genome that can cope.
The point is that plants must adapt to whatever their environment gives them much more so than humans. Human mobility and the ability to modify its environment means it is less reliant on gene-based adaptability.
Two wrongs don't make a right, but three lefts do.
Hmm. Myth-busters I recall disproved that one.
XML UI Browser/Platform
I didn't see Mythbusters. How did they explain it?
Yes they did. They found that it landed butter-side down because when one applies butter on the bread, they make a parabolic indentation, therefore, changing the aerodynamics of the toast.
Yes! I listen to NYC Speedcore and do math at 3AM. I suggest you try it too.
What is the nature and origin of the Universe?
Now that is the real question. And I'm not talking Big Bang or Grand Unified Theory or whatever. I'm talking "Big Picture" here.
What existed before our universe? What is the original nature of existence...of what we call "reality"?
That for throwing it from a building. For it falling off the table, it has enough time for rotating 180 degrees. That simple.
Here's something else interesting:
Tumbling toast, Murphy's Law and the Fundamental Constants
European Journal of Physics 16 172-176 1995
There's a widespread suspicion among the public that toast sliding off a plate or table has a natural tendency to land butter side down, thus providing prima facie evidence for Murphy's Law: "If something can go wrong, it will". Most scientists, in contrast, dismiss such belief as ludicrous. Indeed, an investigation by the BBC-TV science programme Q.E.D. in 1993 claimed to have proved definitively that the whole notion was nothing but an urban myth. However, as I show in the paper, the experiments carried out by the programme were dynamically inappropriate (in that they consisted of people simply tossing buttered bread into the air - hardly common practice around the breakfast table). When the problem of toast sliding off a plate or table is examined more carefully - with the toast modelled as a thin, rigid, rough lamina - it turns out that the public perception is quite correct. Toast does indeed have a natural tendency to land butter side down, essentially because the gravitation torque induced as the toast topples over the edge of the plate/table is insufficient to bring the toast butter-side up again by the time it hits the floor. Note that this has nothing to do with some aerodynamic effect caused by one side being buttered - it is just gravity, plus a bit of friction.However, I go on to show that the tumbling toast phenomenon has far deeper roots than one might expect. If tables were a lot higher - around 3 metres high - the problem of toast landing butter-side down would go away, as the toast would have enough time to complete a full rotation. So why are tables the height they are ? Simple: to be convenient for humans. So why are humans the height they are ? Using a simple chemical bonding model of the human frame, I show that there is a limit to the safe height for bipedal, essentially cylindrical creatures like humans. The limit is around 3 metres - above that height, a simple fall results in gravity accelerating the skull to such a high kinetic energy that the chemical bonds in the skull are ruptured, causing severe fracturing. This limit, in turn, sets a maximum height on tables suitable for creatures with human articulation of about 1.5 metres - which is still not high enough to prevent toast landing butter-side down. It thus seems that human-like organisms are doomed to experience this manifestation of Murphy's Law.
But then comes the real cosmic twist in the tale. The formula giving the maximum height of humans turns out to contain three so-called "fundamental constants of the universe". The first - the electromagnetic fine-structure constant - determines the strength of the chemical bonds in the skull, while the second - the gravitational fine-structure constant - determines the strength of gravity. Finally, the so-called Bohr radius dictates the size of atoms making up the body. The precise values of these three fundamental constants were built into the very design of the universe just moments after the Big Bang. In other words, toast falling off the breakfast table lands butter-side down because the universe is made that way.
Having made this depressing discovery about the nature of our universe, I felt duty-bound to come up with some ways around it. After all, we should not be fatalistic about such things. There are any number of daft ways (eating from 3 metre high tables, eating tiny squares of toast, putting the butter on the underside, tying the toast to a cat, which of course knows how to get right-side up during a fall, etc. etc). The physicist's approach is to minimise the amount of time the toast is exposed to the turning effect of gravity. This means doing the opposite of what you might expect. If your toast is sliding off the table, you should give it a swipe with your hand, to increase its ho
The article on why humans have so few genes [sciencemag.org] does some nice hand-waving but fails to answer the core question. Sure, the genome can do some interesting combinatoric stuff to get more out of a given length of DNA, but that does not answer the question -- why should humans have fewer genes than something so simple as a mustard plant or rice?
Actually, it's mostly that evolution has created DNA sequences, mitochondrial DNA, and various fragments and editing/copying mechanisms that allows it to get a lot done with less than you think, by silencing segments, reusing segments, having offsets for copying, and allowing proteins to shift and rotate.
The world is way more complex than the old days of DNA makes proteins and each segment makes one and only one - everything interacts, mutations occur, copying errors happen, and it's all really kind of beautiful on the proteomics level.
So that isn't really a question anymore - we have enough genes to get the job done, because they have more capabilities than anyone imagined ten years ago.
-- Tigger warning: This post may contain tiggers! --
If the Big Bang isn't a big enough picture that you must be a hard person to satisfy!
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
What, no room for: Yes, but does it run linux?
...your eyes! Not for too long however, just a glimpse would do.
Doesn't it make you feel good to know that our freedoms are protected by politicans, lawyers and journalists.
...What is conventional computing?
Is it binary operations implemented with semiconductors? Is it the use of a monolithic computation device to perform generic tasks?
Or is it something more nebulous, like the ability for an individual's performance to be improved through the use of a computer? The use of an extremely configurable tool to aid in specific tasks with real-world results?
tasks(723) drafts(105) languages(484) examples(29106)
Saturn is rotating slower: And Saturn is rotating seven minutes more slowly than when probes measured its spin in the 70s and 80s - an observation experts cannot yet explain.
If you look, they chose to ask very specific questions about biology and very general questions about physics. That very first question on the list, "what is the universe made of?", could have been easily split into five to ten different specific questions; similarly the list in general contained a number of groups of five to ten biology questions that are in a similar enough category they possibly could have been in some way collated. If they'd done either of these things the balance of the list would have seemed quite different even though the article as a whole was asking the exact same things.
But the way they did it makes sense to me, since it seems (to me) like right now biology has a good grasp on the big picture but is a little confused about specifics, whereas physics is absolutely drowning in specifics and at one of those points where they need some general answers about how all of these specifics fit together.
Irritable, left-wing and possibly humorous bumper stickers and t-shirts
A: 42
Q: a/s/l?
Now you know what the answer means.
A deity capable of creating an entire universe is obviously capable of deceiving you.
--RIAmAses! Let my MP3ople go!
...if the slashdot effect can be successfully used to initiate a self-sustaining fusion reaction.
Clearly, it should have been "the rotational velocity of toast".
LOAD "SIG",8,1
> Saturn is rotating slower: And Saturn is rotating seven minutes more slowly than when probes measured its spin in the 70s and 80s - an observation experts cannot yet explain.
Also check out the Pioneer anomaly.
Sheesh, evil *and* a jerk. -- Jade
Why? Would you still eat it as long as the toast landed butter/jam side up? Does this have something to do with the three second rule?
The Chronic *WHAT* les of Narnia!
That's one that I've wondered about and, last I heard, there was no good answer. It's been about five years since I heard about it, but back then nobody really knew why glass could be seen through.
Martin Gardner says that the superultimate question is: Why does the universe exist?
Or, put another way: Why is there something rather than nothing?
Perhaps this is more of a philosophical or metaphysical question, but I think it fits in well with the great scientific questions.
If you think about it, you'll realize that things would be alot simpler if nothing existed at all. Why does the universe go to all the bother of existing? It's a pretty overwhelming thought -- a good reminder that we still don't know much about the fundamental rules of nature. As Gardner said, "the night is large".
The most rabid believers in American Exceptionalism are the exact same people whose policies are destroying it.
Tidal locking. The increased gravitational field towards the bottom of the toast will act to brake the rotation of the higher mass of the jam as it reaches the lowpoint and starts to rotate upwards.
As an aside, this theory predicts that, dry, unadorned toast will tend to land on it's edge.
Play Command HQ online
The simplest solution is usually the best. Are we alone? yes. Its much simpler to say yes than to expect the insanely high odds that some more elements should combine in the perfect way to create an organism from not much.
"Of all tyrannies, a tyranny sincerely exercised for the good of its victims may be the most oppressive." - C.S. Lewis
It depends on the form you put the problem.
The problem as they describe it (find the shortest possible route through all the locations) is, as far as I know, NOT easy checkable in the way they describe.
If I recall correctly, NP actually describes a set of decision problems for which a positive answer is very easily checkable, but a negative answer might or might not be.
For example, take the question "Is a number composite?". If the answer is yes, it is possible to find a certificate of compositeness (in this case the two factors) that can be used to confirm the result very quickly. However, for a long time it was unknown whether a fast test existed to test the negative of that result (though a polynomial time certificate of primality has recently been found).
In the travelling salesman case, the proper formulation for an NP problem would be "Given a set of distances and a number x, is there a cycle visiting all the vertices with total length less than x?" Now there is a certificate for a positive answer (the cycle in question), but a certificate of the negative result is much harder to come by.
Indeed, and if you strapped a piece of buttered toast to a cat and dropped it, would it just spin in mid air??
The simplest way to solve this problem is to just not drop your toast.
NP defines a set of decision problems, problems with 1 bit of output (yes/no). dictionary.com So the TSP decision version would be "Is there a path visiting all nodes with total length less than X," for some number X. Given a path, to check if it solves the problem you just calculate the length of the path and see if it is less than X.
The snow doesn't give a soft white damn whom it touches. -- ee cummings
TSP is considered NP-complete not because of the optimization version but because of the decision version (given a graph with weighted edges and a length L, is there a tour of length at most L? It's very easy to check whether a solution to this problem is correct--just see if it's well-formed and of length
If I recall rightly, problems whose decision version is NP-complete are called NP-hard.
From the Internet Oracle Best of Digests :
make world, not war
Interesting, I like your answer better than mine :-) I never considered checking negative answers before - are there any NP problems for which a negative is verifiable quickly?
The snow doesn't give a soft white damn whom it touches. -- ee cummings
Of course this would inevitably launch the Buttered Toast arms race, as depicted in Dr. Seuss's Butter Battle Book.
make world, not war
What Is the Universe Made Of? No we don't know what dark matter is, that's why it's called dark.
..probably in S. Korea.
..just some ideas
What is the Biological Basis of Consciousness? If you could solve this you would in essence be "God". The sum of the parts is greater than the whole, and because we tend to determine the workings of all the parts, it's difficult for any one person or persons to see the big picture.
How Much Can Human Life Span Be Extended? For as long as the brain can hold out.
How Can a Skin Cell Become a Nerve Cell? This won't be answered in the US
How Does Earth's Interior Work? Ever watch The Core?
Are We Alone in the Universe? "If we were, it would be an awful waste of space"
Is an Effective HIV Vaccine Feasible? Not if the pharmaceutical companies have anything to say about it!!
How Hot Will the Greenhouse World Be? What you mean you can't tell right now?
What Can Replace Cheap Oil -- and When? The US is the world's largest grower of corn. It can provide enough *biodiesel* for the entire US and then some. The oil cartels and the politicans (e.g. Bush) who have alot to lose if we switch to biodiesel fear this. So government pays corn farmers money (called subsidies) to underproduce or burn excess crop. Granted biodiesel does burn at a higher temperature and would require modification of engine components (probably would be more expensive initially), but in the long run this would be much cheaper for everyone. Currently companies such as Cummins and its subsidiaries are looking into biodiesel.
Are we alone? Almost certainly not; there's no reason it should have happened here and not elsewhere in this insanely large universe. Will we ever find out? Maybe not... how many technologically sophisticated cultures are there actively broadcasting their presence, in the wavelengths we're watching, close enough that we can hear them?
Me (Blog)
Didn't you hear?
The first message has been decoded.
Clear as a bell!
"Send moce Chuck Barry."
That is to a large extent restricted to the US, happily.
Me (Blog)
Dark matter and the biological basis of consciousness are well below the big question: What is knowledge? What is consciousness, and what is truth? This should be answered before the question of what the biological basis of consciousness can be known. We don't even know what consciousness is, so why do we look for its biological basis first?
(The answer to the last question is: We didn't. But we haven't found any good answer yet, unless we believe in Plato et al. But science is, metaphorically speaking, a house of cards built in the air. And I'm saying that with no disrespect to science. (And yes, I'm a bit drunk, but I'm still serious.))
I would have to say that aliens exist. This is based on the fact that if aliens really did exist, no one would tell us. There is alot we're not told
They call me the wookie man, I guess that's what I am
Just how fast do you drop your toast ?????
I'm surprised they didn't mention the great mystery that is gravity.
Probably not, but instead of just having to sweep up some dry crumbs, because it lands on the buttered/jammed face, you have to clean up a sticky mess.
After all, I am strangely colored.
They estimate that this exotic dark matter makes up about 25% of the stuff in the universe--five times as much as ordinary matter.
5 times as common as "ordinary matter", So then... How exactly does this constitute as exotic?
Go ahead and call me unreliable; reliable is just a synonym for predictable.
You are right that polynomial verification of the TSP decision problem exists, and that such verification of the optimization problem doesn't. Interestingly, polynomial solution of the decision problem would imply polynomial solution of the optimization problem (just use binary search).
If I recall correctly, NP actually describes a set of decision problems for which a positive answer is very easily checkable, but a negative answer might or might not be.
Right. Problems (aka languages) for which membership certificates exist are in NP. Problems for which proofs of non-membership exist are in a class called co-NP. If P=NP then NP=co-NP, or conversely if NP != co-NP then P != NP. Obviously, the only problems which are currently known to have both YES and NO certificates are in P. Since TSP is NP-Complete, if certificates of non-membership exist then P=NP. This is unlikely to be true.
That's the best question on the list. If you didn't say it was a joke, would have gotten +25 Insightful.
Actually, it is far more fun to spray a cat's feet with non-stick "buttery" spray, and send the cat off across the linoleum floor... Especially if there is a dog nearby :)
-WS
An operating system should be like a light switch... simple, effective, easy to use, and designed for everyone.
Hmm. Myth-busters I recall disproved that one.
Actually, the proved it. When they slid buttered bread off a table, it landed butter side down, because of the rotational speed of toast and the height of the table. However, if they dropped toast off of a high building, or dropped it edgewise to eliminate this factor, it didn't.
Close. A problem is NP-hard if every language in NP has a polynomial-time reduction to it. If the problem is also itself in NP then it is called NP-Complete.
The simplest solution is usually the best. Are we alone? yes. Its much simpler to say yes than to expect the insanely high odds that some more elements should combine in the perfect way to create an organism from not much.
Occam's Razor is not a basis for determining which hypothesis is correct. Indeed, historically, the simplest hypothesis has usually turned out to be wrong.
What Occam's Razor really is is an algorithm for ordering the universe of possible hypotheses for testing. It is most efficient to start by eliminating the simplest hypotheses, then the next simplest, etc.
Its much simpler to say yes than to expect the insanely high odds that some more elements should combine in the perfect way to create an organism from not much.
In this case, the simplest hypothesis is that the odds are not enormously high, and that given the appropriate conditions, the evolution of life is a near certainty. This would fit with the fact that life seems to have appeared on earth fairly early, almost as soon as the earth's crust stabilized. If it is really such an improbable event, then the average waiting time for life to form should be long. So if formation of life is really improbable, then our planet is not only remarkably lucky to have life at all, but remarkably lucky to have developed it so quickly.
A more practical question: Why is it so hard to make a safe weight-loss pill? Some people are naturally skinny. Why? Enough of this bondage-and-discipline diet and strain crap.
Table-ized A.I.
Once you're using tensor analysis for your physics and engineering homework space/time is a four-dimensional vector. IIRC the spatial dimensions are real, the temporal dimension is imaginary.
For every complex problem there is an answer that is clear, simple, and wrong. -- H L Mencken
"You'll get nothing, and you'll like it!"
That layout *might* have been cutting edge close to a decade ago. Made for painful reading. I expected better from the American Association for the Advancement of Science. Maybe the AAAS should partner with a few artists - you know, hire a web designer... or something.
- Why do we dream?
- Why are there critical periods for language learning?
- What are the limits of learning by machines?
- What Are the Limits of Conventional Computing?
- How Will Big Pictures Emerge From a Sea of Biological Data?
I'm sure Science Magazine would've added more if they had more space, but I really wonder if this is all we're going to solve in the next 25 years...[o]_O
What is knowledge? What is consciousness, and what is truth?
A little bit off topic, but weren't these questions, or some like them, asked in the original recording of Jesus Christ Superstar?
This should be answered before the question of what the biological basis of consciousness can be known.
The ultimate question is, "Is Roger Penrose conscious?"
Tag lost or not installed.
Yes. Death. I have come to the conclusion that acne is a sign of good health. We are living longer than ever and have acne longer than ever. The acne caused by the agricultural poisoning of the Ukrainian prime minister has made me think though. It may be caused by weed and insect poison in out food.
Oh well, what the hell...
What Can Replace Cheap Oil
It's only very expensive oil (perhaps much more than the current $60/barrel) that has a chance of being replaced by something else, something less costly.
I dunno what it would be, but I'm NOT betting on fusion, regardless of temperature.
Tag lost or not installed.
Causality, the very existence of causality, is unprovable within our current frame of reference but that doesn't mean it can't exist, because experientially it does exist.
Ergo if the theory does not fit the observed facts, revise the theory. Of course that gets into what do we mean by experientially? What is the frame of reference that we use to experience the evidence of realty?
Ugh! Too heavy for me...
I'l go back to playing a cowboys & indians with Homer. D'oh!
MSBPodcast.com The opinions expressed here are my own. If you don't like 'em... Think up your own stuff.
Are you entirely certain that it's not the angular acceleration of toast that is the question?
(In fact, glass is a fluid much like water - only a LOT more viscous.)
a ss_being_liquid_at_room_temperature
I've often heard this, and the windows of several-hundred-year-old buildings are often cited as an example of this (a high school physics teacher told this story to the class), with the bottom part of the glass pane being thicker than the top, but I recall hearing an alternative explanation of this. Also, many precisely made pieces of glass, such as binocular lenses and telescope lenses and mirrors, do NOT flow measurably over decades or centuries at normal temperatures.
Googling glass flow bring several relevant links such as this one:
http://en.wikipedia.org/wiki/Glass#The_myth_of_gl
Okay, perhaps glass does flow, but if so the rate of flow is many orders of magnitude slower than would be indicated by the thicknesses of the old glass windows.
Tag lost or not installed.
A major part of science is asking the right questions in the first place.
Questions like "How did cooperative behavior evolve?" make an assumption that cooperative behaviour evolved. Starting out with dubious assumptions often leads to research going in wrong directions.
If one really wished to understand such phenomena the question would be phrased something like:
"What are the origins of cooperative behaviour?"
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife
We all know that particles (i.e. electrons, protons) with opposite charges get attracted to each other.
My question is...
WHY? Yes, I know they're opposite charges, and the Coulomb's law and everything... but why? Any quantum physicist to enlighten me?
The Mythbusters tackled this one. They came up with two explinations.
1) Toast nocked off a table tends to flip only once before landing.
2)When buttering toast, you tend to compress the center of the toast, forming an airfoil alowing the toast to glide down, butter side down.
Sure, it's not hard science, but it's good television.
The opinions in this post are ficticious. Any similarity to actual opinions, real or imagined, is purely coincidental.
Never in this universe.
And there's an army of Parking Wardens out on those mean streets to prove it...
well not wasted but suprisingly interesting.
Indeed!
It is slightly depressing how hand waving the description of the maths problems are, even from a magazine like Science. The desccription of the Poincare conjecture is not much better.
How nice that you have worked it all out for yourself, but, frankly, that's all pseudo-scientific bullshit. Photon's don't "experience" things, and people don't "observe the universe from the outside".
Now if they would finally make cubic baguels, those damn things keep rolling away whenever i drop them
It turns out that the better question to ask is: Why is (opaque substance X) not transaprent?
This is because the 'natural motion' (whatever that may mean) of a beam of light it to pass right through somthing, unless stopped.
Once you answer the question of opacity in general, then the reason that glass is transparent [0] is answered: by the absence of anything to make it opaque.
There are, from memory, two major causes of opacity.
Every surface will scatter some light. Indeed, you can see a reflection in a window, even for a material that is accepted 'transparent'. This is the reason that snow quartz is white and opaque, and rock crystal is clear, despite being exactly identical [1] in chemical composition. Snow quartz is make up of very many small grains, and at the boundary between these grains, a small part of the light is scattered. This mounts up through the thickness of the material, and the result is white and opaque. Rock crystal have very large grains - indeed, it's possible to get lumps that are single crystal as large as several feet across. In practice, one or two grain boundaries can't be seen by the naked eye.
You can also get quartz (same chemical composition again [1]) that has 'small ish' grains. A lump about 3 to 4 inches across will be translucent - you can see light through it, vaguely make out dark patches and light patches when you look throuugh it, but no more detail than that. That just happens to have a grain boundary density somewhere in the middle, to produce this effect.
Glass, as in window glass, is made in such a way that there are no grain boundaries in it. It's actually totally different to the crystaline substances I mentioned above, but the principles of transparency are the same. Glass is an amorphous solid, sometimes described as a 'supercooled liquid'. Indeed, the very conept of grain boundaries can only be found in substances with long range order - i.e crystals, so you'd never get opacity produced in a liquid or a glass from this origin.
Other than grain boundaries, the other major cause of internal changes of surface is a mixture of a solid and something else. This can be two solids (fine dust inside a glass will make it look opaque), a liquid or a gas (the white effect on ice cubes is air that was dissolved in the water, but can't disolve in ice. This forms tiny [and not so tiny] bubbles inside the ice, giving the white bands common to homemade ice cubes.)
So that's one way something can be opaque. Onto an other, and to being, let's also consider colour.
Specifically, lets think about ruby (which is red), and sapphire (which is any colour but red, lets think blue, and clear). Both are mostly the same material, aluminium oxide (Al203), which is clear in a pure, single crystal. Gem quality ruby and sapphire are single crystals, so there are no internal surfaces to scatter light. You can see clearly through such gems, but the light that gets through them is coloured by the material.
In ruby, there is a small quantity of chromium ions present distributed through the structure. These chromium ions absorb light in the visible spectrum (which then gets reemmited in a random direction, somtimes as the same colour, more often as light of longer wavelength [some sort of infra red typically]). The titanium and iron in a blue sapphire do the same sort of thing [2], but the light absorbed results in a different colour.
As I've implied, the exact wavelengths of light absorbed are determined by the chemical make up of the substance. All substances have paricular wavelengths of light that they will absorb - it is only where a substance absorbes strongly in the visible region of light that colour arises. Most materials absorb in the infrared and ultraviolet, depending on what process occurs when it absorbs light.
There are a few more, more obscure, methods of generating colour - if the particle size of a dust is similar to the wavelength of light, then it'll show a colour,
DONT DO THIS!!!
:-)
If you try this, the universe would have to do something drastic to prevent the rest of the universe knowledge of what happened.
This would either be by creating an event horizon arround the cat + toast or by preventing the cat from ever falling (which seems to violate the principle of determinism in the universe or at least something about time travel).
The creation of a event horizon would on the other hand solve the problem form the point of view of the universe, as no information abot what happened would ever escape.
The bad part about this (from our point of view) would be that anything crossing the event horizon arround the cat+toast would stay inside (in effect creating a black hole) which would eventually eat the whole earth.
Come to think of it. Astronomers always wants to study the curvature of spacetime arround a spinning black hole. If they did this experiemnt (somewhere safe like on the moon) and instead of just dropping the cat sent it spinning towards the floor, the conservation of momentum vould create a spinning black hole once the cat+toast almost hit the ground. If done properly, the moon would be transformed to a spinning black hole which could be investigated safley and cheaply by normal astronomy, thus awouding the use of hugely expensive space based telescopes.
At the same time, a spinning black hole conviniently close to the earth could also possibly be used for FTL spaceflight by use of wormholes created close to the event horizon.
Note do not say this to greenpeace etc, they'll likely crucify me for suggesting this..
Yours Yazeran.
Plan: to go to Mars one day wiht a hammer.
What a load of crap. If you held any consistency you would lay it out like this. God has the power but no motive to deceive. A universe without a deity likewise has no motive to deceive. Some humans have the motivation to deceive because they don't want to believe in god (spurious at best, but more likely just lazy thinking), and some humans are motivated to convince you that there is a god. Or how about this. A church has a financial interest in convincing you that there is a god and he wants you to tithe. Or how about by convincing you there is a god, and that god speaks through them, forgives through them, or whatever through them, that therefore you must submit to them and do as they say. I mean really what you wrote is utterly lazy thinking at it's best.
It seems to me if you can answer how memories are stored you automatically answer what is concesness, and then it should be trivial to answer 'How did cooperative behavior evolve?'
'Why Do Humans Have So Few Genes?' and
'To What Extent Are Genetic Variation and Personal Health Linked?'
Are also tightly linked, since genes also have a survival of the fittest battle amongst themselves. A low number of genes must mean that higher numbers of genes are lightly to cause death before you can reproduce.
'What Is the Universe Made Of?' and 'Can the Laws of Physics Be Unified?' are pretty much one of the same too.
thank God the internet isn't a human right.
Nope, actually, they found out that it almost never landed butter side down. From a normal table hight, the bread seemed to land about 50% butter side down. From a great hight, the dent in the slice of bread caused by buttering the toast made the balance tilt towards landing on the UNbuttered side.
In other words, the myth was busted.
Somehow I can't take an argument seriously from a person who doesn't quote sources and can't even spell the main terms of their subject... ... but maybe that's just me.
Interestingly enough, the answer to these sorts of questions (not 100% sure this is one but if not it quickly becomes one), is "because." Either it is simply because the math works out that way (and it is true of the real world), or if you happen to be a theist / etc., its "because god said so."
"Why does it rain? Because God is in Heaven pours water from a huge watering can."
"It's turtles all the way down."
Part of the intent of these answers is to stop the questioning. Even when the answer is "clearly correct" as in the force of gravity, f=G*M1*M2/d^2, it is still appropriate to ask the questions "Is this correct?" and "Why?" These are asked in many high schools and colleges everywhere.
Only 100 years ago, at the advent of powered heavier-than-air human flight, people believed it to be immoral to fly (The old quote "If God had intended man to fly, He would have given him wings" was meant literally). With time, advances in aerodynamics, and cheap commercial airline tickets, most people don't even know it used to be considered immoral.
I am in favor of investigating why each and every turtle is there.
Tag lost or not installed.
I'm surprised that no one is wondering when microsoft will finish winfs?
--- Don't ever trust a woman until she's dead- B.B. King
Questions like "How did cooperative behavior evolve?" make an assumption that cooperative behaviour evolved. Starting out with dubious assumptions often leads to research going in wrong directions.
If one really wished to understand such phenomena the question would be phrased something like:
"What are the origins of cooperative behaviour?"
As I say in the subject, that's an excellent point overall, but as far as use of the word 'evolve' in this question, I would not be hung up on a literal or dictionary definition of that word. The assumptions I would use are: Cooperative behavior did not exist at some past point in time. Cooperative behavior does exist now. How did this change happen?
A problem I see with this particular question is getting a good, objective definition of cooperative behavior, OTOH the scientists who look at this sort of thing (sociologists? anthropologists?) are probably WAY ahead of me on this.
Tag lost or not installed.
If it existed, we wouldn't be trying so hard to replace it.
I hereby place the above post in the public domain.
I believe that would be (1/2)+bi.
I hereby place the above post in the public domain.
Isn't it common Knowledge?: 42
Or better wet, just strap the toast to a cat's back and the two will just stand in the air, rotating until the end of times.
What is interesting is that the time it took to pass from condensed order into uncondensed and expanding chaos from which matter could form, on through today, has happenned along a seemingly reverse exponential curve. One could argue that we are at or slightly beyond the knee of this curve. This is the essense of the laws of thermodynamics, particularly the second law of increasing entropy in a closed system. Unless of course there is something feeding the universe from the outside of it, in which case all bets are off. We have no evidence of this case, though.
Assuming the universe is a closed system, and from order will ultimately come chaos - where does that leave us? Well - what about evolution and intelligence, particularly sentient consciousness? If we look at the system as a whole, we see the universe going from an "ordered" singularity to a chaos of atoms and such, while at the same time, at least in our neck of the woods, we see from this chaos arise life and intelligence. From the general chaos, local order and intelligence arises. This isn't in violation of the laws of thermodynamics. Life and intelligence seems to have arisen from the chaos of the general universe. We know of at least one case. Furthermore, given the immenseness of the universe, there is ample reason to believe that there are other intelligences "out there" as well.
What is further interesting is to look at the advancement of life on the one case we do have that we can look at, here on Earth. Particularly the development of intelligence and technology. Technology can be defined as "improvement of tools in a culture which utilizes tools, along with a record of those advancements". Some insects, birds, and other lesser primates utilise and build tools, but they do not have technology, because they do not keep a history or knowledge of what tools worked best in the past, and how to improve upon them. Only humans have done this (particularly homo sapiens neanderthalensis and homo sapiens sapiens - of which only the latter survived to become us - some have postulated that this may have occurred because of "violent conflicts" between the two groups, with our line winning the conflicts). In a very, very short span of time (compared to the age of the universe), our technology and intelligence has pushed us from hiding in caves to exploring other planets and beyond. Furthermore, our intelligence has enabled us to create machines which in theory, someday soon, could rival our intelligence, and beyond.
Indeed, if you follow the progression of intelligence, technology, and communications among humans (pick a point, say the approximate date of the development of the abacus, and move forward from there with other devices and technology to measure, calculate, and communicate - everything our brains can do) - you will find that if you graph "computing capacity/capability" against "date/time of advance" - that this curve follows on its own, an exponential curve. According to this curve, we are at (or once again, just beyond) the knee of this curve.
These two curves, that of the universe becoming more chaotic, and intelligence becoming more, well, "intelligent" (due to mainly convergence and synergy between technological advances, particularly those which utilize computational technology - a feedback loop of sorts) - have been coined "The Law of Time and Chaos" and "The Law of Accelerating Returns" by RayKurzweil, principally in his work The Age of Spiritual Machines. Interestingly, as the universe moves from order to chaos, life and intelligence seems to arise from this chaos, and from there, intelligence, and
Reason is the Path to God - Anon
or to eat while sitting on or near the floor.
Ergo, time (as is measured inside the Universe) is entirely contained within the Universe, so anybody who stepped outside would not be subject to time.
Time can be likened to the third dimension within a mobeus strip - the mobeus strip itself exists in two dimensions but must encompass a third for the twist to exist. Those on the mobeus strip are incapable of seeing the twist and can only theorize that it must be there for their observations to be valid.
Anyone who stepped off the mobeus strip would see the entire construct, with all dimensions present.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
The Aristotalian model of space/time was from the perspective of a theoretical outside observer. Later corrections to this model, by Newton and Einstein, are based on mathematical models and cases that are largely outside the realm of day-to-day observation.
(I consider Aristotle's observations of carts and boats to largely agree with those of modern people, as such objects do not undergo forces or accelerations such that the corrections are significant.)
Since the "external" frame of reference is closest to actual, day-to-day mundane observation, that is the "common sense" frame of reference and therefore the one that people will use unless there is reason to do otherwise.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
If I have "figured anything out", it is that "big questions" rarely need big answers, and even Occam got there before me.
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Ah, but this is only a theory. The far more "useful" theory tend toward creating this toast-cat mixture, then strapping magnets to its back, thus creating a generator of unlimited power! Enough cats and enough buttered toast, and who needs cold fusion?
Seriously now if the editors can post dupes why can't re readers post duplications in the comments. And yes this is meant as a joke