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 Author Thread: In an infinite universe...
 The other guy

Joined: 1/19/2008
Msg: 101
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In an infinite universe...
Posted: 10/9/2008 9:55:18 PM
Just as a side note: intelligence is got nothing to do with living a "life worth living"...according to another forum on here allot of people seem the think it has everything to do with an IQ score....problem solving ability!?! (not my opinion). The "life worth living," thing is too subjective and allows an easy way out while offering no meat and potatoes for the dinner table of wisdom. Abelian, is trying to get around this subjectivity, by offering a few old ideas re-heated on a new plate. His approach is fresh and note worthy; only his tone needs adjustment.
 Light Storm

Joined: 5/23/2006
Msg: 102
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In an infinite universe...
Posted: 10/9/2008 11:56:38 PM
To OP

I like the alternate view on universes from the perspectives of the mathematical string theories. If anyone reading this is unfamiliar with string theories, they are basically the building blocks of exsitance (if there real at all) . To give you an idea... if you where to look at it from the levels of magnification you have 1. Macroscopic level - Matter 2. Molecular level 3. Atomic level - Protons, neutrons, and electrons 4. Subatomic level - Electron 5. Subatomic level - Quarks... and than... you reach 6. String level.

Considering the LHC was built to understand more about level 5, level 6 can still only be made up in math. Anyways... "...All string theories predict the existence of degrees of freedom which are usually described as extra dimensions. Without fermions, bosonic strings can vibrate in a flat but unstable 26-dimensional space time. In a superstring theory with fermions, the weak-coupling (no-interaction) limit describes a flat stable 10-dimensional space time. Interacting superstring theories are best thought of as configurations of an 11 dimensional supergravity theory called M-theory where one or more of the dimensions are curled up so that the line-extended charged black holes become long and light..." ~http://en.wikipedia.org/wiki/String_theory
 abelian

Joined: 1/12/2008
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In an infinite universe...
Posted: 10/10/2008 10:20:05 AM

Lets take the nuclear bomb as an example. The creation of this technology was by a group of people so pre-occupied with "could we" they never stopped to ask themselves "Should we?"


Your comment is specious. The fact is, that by studying nature, one is going to find out how nature works. After that, developing a use for that knowledge is engineering. Knowledge has no morality either way and the people who drive applications for it like bombs are politicians and the people who elect them. The internet started as a military project. Does that make it bad or does the concept of ``bad'' depend upon how people use it?
 abelian

Joined: 1/12/2008
Msg: 104
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In an infinite universe...
Posted: 10/10/2008 10:31:56 AM

I'd like to suggest that tolerance is paramount with people we don't agree with today (ie: Webweebill) because the conflict of ideas is a necessary condition to learning, and getting ideas from all angles is a good thing. Let's encourage discussion rather than try to silence a few we don't agree with. Do we have to label things we don't agree with as crap?


I have a great deal of tolerance when someone is willing to think. I've become very intolerant with those are willfully ineducable. The willfully ineducable who persist in believing whatever they want to believe believe because thinking is hard, are the ones responsible for the misery that exists in the world. Have you ever noticed the extent to which anyone with an agenda can acquire a following by becomming the conduit and spokesperson to some supernatural force? I'm willing to listen to anything for which concrete evidence exists for any phenomenon which can't be explained by science. But that isn't what webweebill is offering. He's offering the chance to de-educate people to bring them down to his level of ability to understand the world around him. No educated person should tolerate advocacy of ignorance.
 quietcowboy

Joined: 12/25/2007
Msg: 105
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In an infinite universe...
Posted: 10/10/2008 10:39:00 AM

Lets take the nuclear bomb as an example. The creation of this technology was by a group of people so pre-occupied with "could we" they never stopped to ask themselves "Should we?"


Had they stopped to ask "Should we" and not done it then it probably would have happened any way. It is rocket science in terms of what we know today, in fact the materials & science behind it was serendipidously discovered by Fermi and others in an attempt to fill out the periodic table. Using that knowledge to develop a weapon was engineering.

Having said all of that, the scientist involved probably did more for world peace than the could have ever known. For two hundred years leading up to the development of atomic weapons, the world was averaging a huge war between super powers about every forty years. Since then none. I don't like the idea of putting a gun to someone's head and telling them if they commit a violent act they will be killed instantly, which seems to be what atomic weapons accomplishes, but I'd have to say that it has worked out so far!
 stargazer1000

Joined: 1/16/2008
Msg: 106
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In an infinite universe...
Posted: 10/10/2008 10:39:38 AM

Though I like what I'm hearing from and agree pretty much with Abelian, I'd like to suggest that tolerance is paramount with people we don't agree with today (ie: Webweebill) because the conflict of ideas is a necessary condition to learning, and getting ideas from all angles is a good thing.


I agree OT, but that tolerance is something that has to take place on both sides of a clash of ideas for a higher level of discourse to take place. Otherwise, it just becomes a childish exchange of insults which is something that happens on an all-too-frequent occasion on these forums.
 quietcowboy

Joined: 12/25/2007
Msg: 107
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In an infinite universe...
Posted: 10/10/2008 10:46:43 AM

It is rocket science in terms of what we know today, in fact the materials & science behind it was serendipidously discovered by Fermi and others in an attempt to fill out the periodic table.


A typo, it should have read "It ISN'T rocket science" ...sorry about that.
 stargazer1000

Joined: 1/16/2008
Msg: 108
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In an infinite universe...
Posted: 10/10/2008 10:48:29 AM

Knowledge has no morality either way and the people who drive applications for it like bombs are politicians and the people who elect them.


Knowledge has no morality, but its the application of that knowledge that must. That said, "morality" is a very subjective viewpoint. It's easy for us standing off 60 years hence to debate the application of the atom bomb since few of us were around at that time.

At the risk of getting into word games, to me "morality" is a question of intent. As abelian points out, religion has used morality - often a set of specific and restrictive rules - as a means of subjugation ("behave as we dictate or you will go to a horrible place when you die") and a method of gaining followers, usually for the leader's own gratification.
 stargazer1000

Joined: 1/16/2008
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In an infinite universe...
Posted: 10/10/2008 10:49:52 AM

A typo, it should have read "It ISN'T rocket science" ...sorry about that.


In some ways, it was.
 The other guy

Joined: 1/19/2008
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Posted: 10/10/2008 12:18:49 PM
"Knowledge has no morality either way and the people who drive applications for it like bombs are politicians and the people who elect them"

I think scientists have to maintain a sense of "morality" about what knowledge they pass over to the rest of society. Just because they seek knowledge for the sake of knowledge, it does not exempt them from being responsible individuals within a global society. On a smaller scale, most people would agree it would be unethical for me to hand a bunch of kids a piece of paper showing them how to make a simple bomb from common household items. Then when confronted about it, I just say, "hey dude, I just sold some information, what they do with it is no concern of mine, I never told them to actually build a bomb and take it to school." It seems scientists should be more concerned about who they work for, and what the implications are of what they are developing. Double of the same goes for the engineers. If everyone took more responsibility in this area, the dangers of discovery and invention would be greatly reduced, however, so would the pay cheques of scientists and engineers.

Ok no more digressions... in an infinite universe where everything is infinitely infinite and nothing can be of the same value as everything, there is nothing more infinite than the conflicts within our own thinking. An infinite universe in idea is impossible for us to work with as a theory. Besides, even if we prove it is conceivable, what's the point? What is gained?

The other guy
 Light Storm

Joined: 5/23/2006
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In an infinite universe...
Posted: 10/11/2008 7:49:15 AM

Your comment is specious. The fact is, that by studying nature, one is going to find out how nature works. After that, developing a use for that knowledge is engineering. Knowledge has no morality either way and the people who drive applications for it like bombs are politicians and the people who elect them. The internet started as a military project. Does that make it bad or does the concept of ``bad'' depend upon how people use it?


I don't care about the politician that wants a hundread nuclear missiles... I'm scared shi!less of the person who wants one.

Your right knowledge has no morality until that knowledge becomes reality... kinda like VX Gas... "Oh... lets see what happens when we put this stuff together.... oh, so not cool!" now it's a technology so evil that even the people that came up with it wish it was something they could dis-invent.

You might call them 'intelligent' for being able to come up with it... I would call them an 'idiot'
 The other guy

Joined: 1/19/2008
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Posted: 10/11/2008 8:28:01 AM
I agree knowledge can have no morality in itself, but the PEOPLE developing the knowledge can, and should have morals. Just don't develop anything knowing full well where your knowledge will end up (ie: working for the highest bidder in the nicest labs but developing some of the most nastiest things for no good use).
 ExtraSalty

Joined: 11/17/2006
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Posted: 10/11/2008 8:36:27 PM
This question is being completly misunderstood here. There is no data that indicates that there are multiple universes just as there is no definitive proof that dark matter exists (as dark matter does not act any different then matter that is just nearly impossible to observe). This theory has been created to explain more philosophical reasons of why this universe exists as it does. The thought behind this is if there is an infinite ammount of universes and each universe abides by each of thier own set of laws (it is not nessesary for alternate universes to have the same laws ex the same value of constants) then only a certain set of universes can exist that that could support life at all immagin a universe where electic or gravitational force was an order larger or smaller. Because of this you can assume our universe is of a select few universes that can support life and allow us to even ask this question. Any mention of black holes as warpholes or whatever is moot as that was an application after the fact and noone can possibly know what happens on the other side of a singularity, even if it was true most theorists beieve a warmhole wouldve been warped back into space time into another part of this universe.

In short this is more of a philosophical question to answer why our universe.
 karma9800

Joined: 6/21/2007
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Posted: 10/11/2008 8:49:34 PM
This is an intriguing part of theory that verges onto the same boat as the religious possibility of a God. God being a word or definition of something omnipotent and all knowing.

How big is our universe?

Well to answer that we have to look around it and attempt to scale it or measue it.

But here is the first problem.

How far can we actually see?
Is the Universe merely as big as our radio telescopes?
If we can listen or look x amount of billions of miles then what exists 1 mile beyond that limitation?

We can only comprehend or acknowledge as far as we can perceive. If we were to be able to see beyond and all encompassing, then would we not be, for want of a better word, God.

Generally we think in terms of spatial distance and perception. We all know what a mile is, how far it is, we can see a mile, we can run a mile, we know how long it can take to pass that mile.

Once we get into the numbers and distances offered by our present and known universe things can start to look multi dimensional. And if the pub was 4 universes and 8 dimensions over from where we live, oh my god all we want to know is how long will it take to get a pint!!!

:)
 meetheye

Joined: 1/2/2008
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Posted: 10/11/2008 9:25:05 PM

There is serious investigation taking place into the possibility that all we see is only a small part of a much greater whole, specifically that our universe is only one of perhaps an infinite number of universes. It's part of a matrix of continuous "creation" for lack of a better, less religiously-charged phrase.

If that is the case, don't all probabilities begin to approach 100 per cent? Somewhere, somehow, a species of "pig" actually evolved the capacity to fly? There's actually an honest car salesman? The government is really there to help someone?

Silly examples, I know, but you see my point. What are the implications of it?[/quote


well from my perspective this is a vey religiously charged proposition. to deal with the scientific implications first though... for a multiverse of infinite universes to exist time as it is relative to your perception would have to cease to exist, it would only be a quantum system where your only point of reference for time would be your current manifestation. What I mean is that your birth and death way of life would become a sort of eternal state of existance. This seems impossible with the current model of the universe as generally accepted by science. If you were to think outside the box though, and focus on the possibe and accept the existance of such 'infinities' rather than closing your mind and saying it's impossible because there is no proof of such existance, then we have a debate because this universe and all it's laws would most definitely want to be eternal relative to all other universes. kind of like ego.

As for your flying pigs example, it wouldn't nessesarily happen in our universe, but in other universes it could be the norm. just because something is the norm for most universes doesn't mean it isn't impossible in whatever universe you're focusing on(1+1 will always be 2 not three because that is the law in this universe). take gravity for example, it is one of the laws that actually gives you a perception of what the universe is. I think gravity exists in the multiverse aswell. Not so much as it relates to matter but on a quantum level where only similar manifestations occur relative to the patterns that emerge. sort of like the similarities and difference from the dream world to the real world. perhaps the honest salesman would get a true sense of self worth because he subconciously knows that he is the only one not only in his universe but the multiverse aswell.
 scorpiomover

Joined: 4/19/2007
Msg: 116
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In an infinite universe...
Posted: 10/12/2008 4:05:28 AM
RE msg 75 by loverofwisdom:
While there aren't any applications of Cantor's work on transfinite numbers I'm not going to say that they can't be applied in physics.
There ARE plenty of applications of Cantor's work on transfinite numbers. Scientists in Physics and the rest of Science are just ignoring Cantor's work right now, because Cantor showed that the ZF axioms don't properly describe our world, and that really scares scientists, because it means that everything they know is "relative".

As a side note I take issue with your usage of "abstract concept" as you seem to be using it as "nonexistent". Abstract concepts may very well exist and they may exist independent of minds (Plato, Frege, et al).
I agree. 2 is just such an abstract concept. You can argue that 2 is just a re-ification, that it has been created by our own minds. But we all have it, we all use it, and no-one could imagine the laws of science working without it. If it was abstract, we could just forget about it, and the world would continue the same anyway. I really cannot see that happening.

RE msg 76 by INTOART:
If you don't already know that quantum mechanics is the basis of modern electronics, then you have far more to learn about that subject than I or anyone could teach you on a mere forum! Start with a basic textbook.
Even the transistor (the fundamental unit of integrated circuits) is based on electron tunneling, which is a quantum effect.
In my opinion, it would be clearer to say that modern electronics relies almost completely devices on ONE flexible type of device, semiconductor devices, such as the solid state transistor, which were based on quantum theory. It's a subtle difference. It's the difference between saying that vaccines are based on science, and vaccines are based on germ theory. One is a lot clearer than the other.

RE msg 78 by loverofwisdom:

This is true. But your two new spheres will still have the same volume as the old one.
I think that's what I said but I'm not sure what you're saying. Are you saying that each new sphere has the same volume as the original or are you saying that the sum of their volumes are equal to the original?
I'm saying that the sum of the 2 spheres is the same volume as the original. Each sphere will end up having half the volume of the original.


It's a description of something we're heading towards, but never actually achieve.
Because we never achieve infinity, we never find out what happens at infinity.
This distinction, minimally, dates back to Aristotle in that infinity is always potential, never actual because we never "get there". This was Poincare's objection to Cantor's work.

Cantor's work is actually in contradiction to Aristotle's thesis here. From what I understand he does actually take time to argue why there can actually be an actual infinity but I haven't read his argument. What I can tell you is that actual infinity is essential to mathematics. Bertrand Russell found it necessary to assume the axiom of infinity; he tried desperately to avoid it but was unable to do so. ZFC also has as one of its axioms the axiom of infinity. So as far as mathematicians are concerned, infinity is not merely potential. An actual infinity seems to be indispensable to mathematics unless some able mind can figure out how to do mathematics without it.
There are 3 potential views:
1) That infinity doesn't exist, and we only approach it.
2) That infinity does exist, and it exists as a number as real as 1, 2, or 3.
3) That infinity does exist, and it exists, but not as a number, and not in the same way as 1, 2, or 3.
I choose #3.

Consider the distance between 0 and 1, say on a ruler. That distance exists. We can see it, and it has a length of 1.
Now cut it in half. Then cut that in half. Do that again and again and again. We can keep cutting it in half, so there are an infinite number of dissections, and an infinite number of distances between 0 and 1. But the distance between 0 and 1 is still 1, and still finite. So infinity exists but we never get there, relative to the distance between 0 and 1.

Now, let's argue the opposite: imagine that there is a finite distance, that we will reach, and at that distance, we cannot subdivide the ruler any more. Then we cannot measure that distance, because if we did, then we could cut it in half too. But then we cannot see that distance. The distance between the 2 ends of that subdivision are right next to each other. So that distance is 0. But then if we add all those subdivisions up, we are just adding zeroes to each other, and hence the total distance of the ruler is 0. But we know that the distance of our ruler is 1. That is a contradiction.

So the only way that we can measure distance is to accept that distance can be measured, and subdivided infinitely at the same time, but that an infinite number of subdivisions of the ruler cannot be compared to the whole ruler itself.

Infinity only exists as an approximation to the number system that we are comparing it to. But in its own right, it must exist.

That is what Zeno's Paradox shows us. That

Our systems of measuring and counting are relative to our system of measurement, and our system of counting.
That is why Xeno had a paradox. That is why Cantor's theorem relies upon a proof by contradiction. Our very system of counting must be self-contradictory, for it to work in the first place. But it doesn't have to be contradictory within its own system, only when comparing different levels of the same system.

RE msg 99 by Light Storm:
Lets take the nuclear bomb as an example. The creation of this technology was by a group of people so pre-occupied with "could we" they never stopped to ask themselves "Should we?"
Lots of people ask that question every single day. You think that only Einstein considered the possibility of getting access to the incredible power that binds matter together? You think that only Alfred Nobel was interested in chemical explosions? There are plenty of people out there right now, who could make weapons far in advance of our own, yet who choose not to work in weapons research, because they see how people use existing weaponry, and see little point in making more. But you don't hear of them, because they don't publish their ideas. If they did, then those ideas would be available, and that is exactly what those people have chosen not to do.

But there are some advantages to the bomb. After all, we have nuclear power, and we're not dead yet. But it cost a few hundred thousand lives, and a lot of anxiety. So there are 2 sides to the story.

RE msg 103 by abelian:
Knowledge has no morality either way and the people who drive applications for it like bombs are politicians and the people who elect them. The internet started as a military project. Does that make it bad or does the concept of ``bad'' depend upon how people use it?
If someone tells you how to make a weapon that will make you rich, but is easily copyable, and if ONE such weapon ever falls into the hands of terrorists, that would make it easy for any terrorist to kill thousands with one push of a button, would you give it to the military, knowing that at some point, it almost certainly will fall into the hands of terrorists? Or will you gamble that all the terrorists will be killed or incarcerated before that happens, and there won't be any more terrorists, before any of them gets hold of that weapon?

Either you are optimistic about the security services, and pessimistic about the abilities of terrorists, or you aren't. I am not going to gamble with your life, based on who I want to feel. My feelings will help me, but they aren't very interested in your happiness.

RE msg 100 by The other guy:
Are we still talking about the reality and/or theory of an infinite universe, or are we just trying to show who is best at casting shadows on other peoples life perspectives?
When we are start talking about infinities, then we start wanting to understand what infinity is. Infinity is a paradox in its own right, in that it does and does not exist, according to what you are comparing it to.

Let's encourage discussion rather than try to silence a few we don't agree with. Do we have to label things we don't agree with as crap? Can we be a little nicer even when we beg to differ?
I agree. Let's be like infinity. Infinity can exist and not exist at the same time, that things can be right and wrong at the same time. Can we accept that? That we can be right and be wrong, both at the same time?
 stargazer1000

Joined: 1/16/2008
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In an infinite universe...
Posted: 10/12/2008 7:16:05 AM
Something that adds to this discussion (I hope) is this article on Space.com:

http://www.space.com/scienceastronomy/080923-dark-flows.html

Upshot: Matter is moving in a uniform direction but without any apparent cause. The idea is that - perhaps - there is a source of gravity that is beyond our observable horizon acting on matter on the universe. This was, of course, counterintuitive. After all,how can something exert an influence and yet be invisible.

One physicist on an RASC discussion board I belong to suggested that - perhaps - it is matter on a separate "Brane" from ours that could be exerting a gravitational influence. Not the final word by any stretch of the imagination but certainly evocative of the subject at hand, dontcha think?
 stargazer1000

Joined: 1/16/2008
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In an infinite universe...
Posted: 10/12/2008 7:21:16 AM

In short this is more of a philosophical question to answer why our universe.


Except that answering such questions is behind what science is trying to accomplish. Actually, the title of my post should probably have read "In an infinite multi-verse" since that is really what we're discussing. Our universe as only one of a multitudes.

And that is something not just the purview of string theory. Quantum theory also suggests that universes are "budding off" our universe and our universe likely budded off another, and so on.

A lot of this is so far unproveable. However, that isn't stopping scientists from doing the math and seeing where it takes them.
 loverofwisdom

Joined: 1/24/2004
Msg: 119
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In an infinite universe...
Posted: 10/12/2008 12:04:24 PM
scorpionmover wrote:


There ARE plenty of applications of Cantor's work on transfinite numbers. Scientists in Physics and the rest of Science are just ignoring Cantor's work right now, because Cantor showed that the ZF axioms don't properly describe our world, and that really scares scientists, because it means that everything they know is "relative".


ZF is post-Cantor. I assume you are referring to Godel's theorem though that isn't problematic for physics as such - it just shows that mathematics is not reducible to formal systems.


I'm saying that the sum of the 2 spheres is the same volume as the original. Each sphere will end up having half the volume of the original.


That's incorrect. What makes the Banach-Tarski Paradox a "paradox" is the fact that it goes against our geometrical intuitions: the two spheres are both individually the same size of the original; the volume is doubled in the process.


Now, let's argue the opposite: imagine that there is a finite distance, that we will reach, and at that distance, we cannot subdivide the ruler any more. Then we cannot measure that distance, because if we did, then we could cut it in half too. But then we cannot see that distance. The distance between the 2 ends of that subdivision are right next to each other. So that distance is 0. But then if we add all those subdivisions up, we are just adding zeroes to each other, and hence the total distance of the ruler is 0. But we know that the distance of our ruler is 1. That is a contradiction.


I'm not entirely following you on this point. I think the supposition that, say, length has natural units (something derived from the Planck length) and that all lengths are some multiple of those natural units and therefore cannot be divided further. This doesn't imply you couldn't measure them per se, their measure would be "1" or to put it another way, you can't measure them but you can count them. Our forms of measurement then are reduced to forms of counting (a distinction that can potentially address some of Zeno's paradoxes.) So we aren't adding "0's" we'd be adding "1's". (Even if we were adding "0's" it still wouldn't necessarily be 0. This is how calculus proceeds by dividing up, say, the area under a curve into infinitely small parts and adds them up to get some value which isn't necessarily equal to 0.)

On Zeno, we can introduce this notion of "measuring" and "counting" and the concepts that go with them and suggest that some of his paradoxes are category mistakes of this kind. One of his paradoxes can be sketched in the following way:

Suppose I am at some point A and I want to arrive at some point B different from A. In order to do that I must get half way between A and B at some point C. Now in order to get to point C I must arrive at some half-way point we'll call D and so on. In this way I will never arrive at the next point.

The next point might be thought of as an intuition that comes from our counting methods. We always have a next number (1, 2, 3, 4, and so on) and we can specify what the next number is. When dealing with sets that are "dense" such as the rationals, there is no next number; there are infinitely many rationals in between any two rationals. The notion of "next" only applies when we are counting, not measuring.


That is why Cantor's theorem relies upon a proof by contradiction. Our very system of counting must be self-contradictory, for it to work in the first place. But it doesn't have to be contradictory within its own system, only when comparing different levels of the same system.


I'm not sure where you're even going with this. Proof by contradiction is a standard technique in mathematics and logic. It simply assumes some statement P, derives a contradiction from assuming that proposition and then concludes that P must be false.
 abelian

Joined: 1/12/2008
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In an infinite universe...
Posted: 10/12/2008 2:00:48 PM

If someone tells you how to make a weapon that will make you rich, but is easily copyable, and if ONE such weapon ever falls into the hands of terrorists, that would make it easy for any terrorist to kill thousands with one push of a button, would you give it to the military, knowing that at some point, it almost certainly will fall into the hands of terrorists? Or will you gamble that all the terrorists will be killed or incarcerated before that happens, and there won't be any more terrorists, before any of them gets hold of that weapon?


I have news for you. Building an atomic weapon is not very difficult. It requires collecting enough fissionable material as close together as possible in a very short amount of time. This has been known for over half a century. The only thing which prevents any country (or group of terrorists) from constructing one is getting enough enriched 235U to make it. One needs only to calculate the probability of fission from an incident neutron as a function of energy to determine the volume of a sphere (or any other shape) of 235U required to go supercritical. (It doesn't have to be particularly efficient, so there is no reason to get fancy.) If the data weren't available, a peecee and a few data points would make the task fairly straight forward.

Stop appealing to emotional arguments. Those have zero merit and are a dead giveaway for a lack of any logic. The real secrets of any concern here are designing efficient weapons and creating encrypted interlock schemes to prevent someone from making use of bomb which gets dropped but fails to explode. Even where encryption is concerned, encryption is not considered secure if it depends on hiding the encryption algorithm or the details of the implementation.

No one has the right to supress knowledge.
 abelian

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Posted: 10/12/2008 2:12:22 PM

In my opinion, it would be clearer to say that modern electronics relies almost completely devices on ONE flexible type of device, semiconductor devices, such as the solid state transistor, which were based on quantum theory. It's a subtle difference. It's the difference between saying that vaccines are based on science, and vaccines are based on germ theory. One is a lot clearer than the other.


You seem to get the cause and effect backwards a lot. Quantum mechanics tells you what properties the materials must have to produce the phenomena needed for things like transistors and it also tells you all of the ways to change its properties to create lots of variations so that it's very flexible, as you put it. The choice of materials is dictated by the materials that exist in this universe which have the properties necessary to function as the equations predict. The choice of materials was not arbitrary and semiconductors were not discovered blindly by trial and error. Since there exists no theory which is an alternative to quantum mechanics, quantum mechanics and science are the same thing. Ditto for the germ theory, unless you dispute the existence of microorganisms or their responsibility for infections and disease AND have a better theory which explains germ theory as a subset.
 scorpiomover

Joined: 4/19/2007
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In an infinite universe...
Posted: 10/12/2008 4:38:09 PM
RE msg 119 by loverofwisdom:

There ARE plenty of applications of Cantor's work on transfinite numbers. Scientists in Physics and the rest of Science are just ignoring Cantor's work right now, because Cantor showed that the ZF axioms don't properly describe our world, and that really scares scientists, because it means that everything they know is "relative".
ZF is post-Cantor. I assume you are referring to Godel's theorem though that isn't problematic for physics as such - it just shows that mathematics is not reducible to formal systems.
From what I understand, the ZF Axioms needed to be re-written to avoid calling the "set of all sets" a set, and it was Cantor's theorem that pointed to it being a set. I do kind of think of Godel's theorems as consequences of Cantor's theorem, because he relies on the negative self-referential construct, "this statement is a lie", and so does Cantor's, and the conclusions of both are so similar to me, that it is a bit hard for me to separate them. However, I've thought long and hard about Cantor's theorem, and what I've realised is that even with the maths that I was taught, you cannot escape a lot of consequences of that theorem, that show severe flaws in the way mathematics is currently approached. But that's my opinion. I haven't published any of it. I've just worked out some ideas on my own.


I'm saying that the sum of the 2 spheres is the same volume as the original. Each sphere will end up having half the volume of the original.
That's incorrect. What makes the Banach-Tarski Paradox a "paradox" is the fact that it goes against our geometrical intuitions: the two spheres are both individually the same size of the original; the volume is doubled in the process.
I imagine that is what the paradox proposes. However, I did look up the paradox, and the proof. I didn't understand it completely, as I really need to discuss it with someone to get it clear in my mind, and it's been years since I was studying it full time, so it's not something I can just pick up and read right now. However, a few things stood out to me, and one of them was that infinite subsets were used within the proof in order to prove the penultimate part, but not as part of the final solution. What occurred to me, was that if we restricted the proof to not use infinity at all, then the proof would probably not hold as true. But then the use of infinity would seem to me to be integral to the proof. So if we considered restructuring the proof to make the use of infinity clearer, it seemed to me that the it would become clear that the proof relies upon us being able to subdivide the old sphere into an infinite number of segments, but that when we combine the segments into 2 new spheres, we rely upon being able to combine only a finite number of segments. So I believe that the proof is unbelievably useful in understanding how we can alter the structure of matter, but that it is flawed in proving we can end up with twice the volume.

Consider the same sphere. But now, imagine that it is made of water, enclosed by a covering of infinitely thin, but infinitely strong plastic. Imagine that whenever we subdivide the sphere, we enclose each part in a covering of the same type of plastic. Because the plastic is infinitely thin, it has no volume, so we can ignore it, and only consider the volume of the parts. In the beginning, we have the sphere S, with volume V. If we cut it into 2 parts, S1, and S2, with respective volumes V1 and V2, then V1 + V2 = V. We can confirm this by opening the plastic, and pouring them into a jar, and measuring the liquid.

If we then subdivide S1 into 2 parts, S11 and S12, with respective volumes V11 and V12, then V11 + V12 = V1. We can do the same for V2. We can keep repeating the process, until we have enough parts that will recombine to make 2 new spheres, T1 and T2, each composed of several parts of S. But at every point, the sum of all the volumes of the S-parts, the Vs, will always add up to V, the original volume.

Even if we reach an infinite number of segments, then at that point, we must rely on integration. But since the parts are composed of water, not solid mass, they are already continuous volumes, and so any integration will yield the same result as when we still have a finite number of parts.

So I really don't see how it is possible to get more than we started with, even on a theoretical basis.


Now, let's argue the opposite: imagine that there is a finite distance, that we will reach, and at that distance, we cannot subdivide the ruler any more. Then we cannot measure that distance, because if we did, then we could cut it in half too. But then we cannot see that distance. The distance between the 2 ends of that subdivision are right next to each other. So that distance is 0. But then if we add all those subdivisions up, we are just adding zeroes to each other, and hence the total distance of the ruler is 0. But we know that the distance of our ruler is 1. That is a contradiction.
I'm not entirely following you on this point. I think the supposition that, say, length has natural units (something derived from the Planck length) and that all lengths are some multiple of those natural units and therefore cannot be divided further. This doesn't imply you couldn't measure them per se, their measure would be "1" or to put it another way, you can't measure them but you can count them. Our forms of measurement then are reduced to forms of counting (a distinction that can potentially address some of Zeno's paradoxes.) So we aren't adding "0's" we'd be adding "1's". (Even if we were adding "0's" it still wouldn't necessarily be 0. This is how calculus proceeds by dividing up, say, the area under a curve into infinitely small parts and adds them up to get some value which isn't necessarily equal to 0.)
I can see your argument. But consider that in order to say that we count those parts, say as Planck lengths, then we still have x many Planck lengths. But we never measured them. We cannot say they are Planck lengths. They could be a different length than the Planck length, and we wouldn't know the difference because we never measured them. Even if we did know that all of the smallest lengths are Planck lengths, we still might not know if we split them far enough and they are really multiples of Planck lengths. Even if we split them to the smallest length possible, we would still need to be sure that we split ALL of the segments to the smallest length possible. So if we recombined them, we could have x many Planck lengths, which add up to y metres, but the actual length of the distance might be z metres, which could be less or more than y.

In order to count these finitely small lengths without measuring them, we would first have to state that we have a theory that proves that everything is composed of Planck lengths, and that we have a way to unique determine which objects are the Planck length, without ever measuring them, but using some other property.

That is quite a leap. If we did that, we wouldn't need to consider infinity as a real concept in the microscopic world. But there still might be an infinity in the macroscopic world, by how big a single object could get. So we'd need a maximum length, and a way of detecting whether an object achieved that length, without measuring it.

We would need a similar theory and detection method for counting.

That's quite a tall order. But if we did all that, we would only have eliminated the need for infinity within the measurements and counting of the physical world. We would not have shown that infinity doesn't exist, only that we don't need it for THIS unvierse.

In a universe without such theories and methods, the principle would still apply, so infinity would still exist. Since infinity would still exist in ONE universe, infinity must exist. We just wouldn't need it in THIS universe.

Even if we showed that such theories and methods applied to ALL universes, we could still state the infinity would exist in an abstract universe without these theories and methods, so infinity stil exists, but we couldn't be sure that it exists in the physical realm.

However, since we cannot be sure that infinity exists in the physical world anyway, we are no worse off than we started.

On Zeno, we can introduce this notion of "measuring" and "counting" and the concepts that go with them and suggest that some of his paradoxes are category mistakes of this kind. One of his paradoxes can be sketched in the following way:

Suppose I am at some point A and I want to arrive at some point B different from A. In order to do that I must get half way between A and B at some point C. Now in order to get to point C I must arrive at some half-way point we'll call D and so on. In this way I will never arrive at the next point.

The next point might be thought of as an intuition that comes from our counting methods. We always have a next number (1, 2, 3, 4, and so on) and we can specify what the next number is.
I can quite understand this. But imagine in Zero's example, that you get to infinitely many distances. How many distances can you count? Theoretically, you could count them all. But you'll never count them all, because it would take an infinite amount of time to count them.

When dealing with sets that are "dense" such as the rationals, there is no next number; there are infinitely many rationals in between any two rationals. The notion of "next" only applies when we are counting, not measuring.
I think you mean the Reals. The set of rational numbers is equivalent to the set of integers and the set of natural numbers (1, 2, 3, 4, ...)


That is why Cantor's theorem relies upon a proof by contradiction. Our very system of counting must be self-contradictory, for it to work in the first place. But it doesn't have to be contradictory within its own system, only when comparing different levels of the same system.
I'm not sure where you're even going with this. Proof by contradiction is a standard technique in mathematics and logic. It simply assumes some statement P, derives a contradiction from assuming that proposition and then concludes that P must be false.
Proof by contradiction is a very valid method. I've used it a lot. But that merely implies an alternative method of deduction is true, that doesn't need it. I guess that I could have said that our system of counting must be inconsistent, in that it must contain a contradiction. That doesn't mean that the system is wrong. That means that our understanding of counting doesn't quite explain the way that counting works, and that in reality there is a deeper system that we are using, that we hitherto have not explained.

In short, counting is not the whole story.

RE msg 120 by abelian:
I have news for you. Building an atomic weapon is not very difficult. It requires collecting enough fissionable material as close together as possible in a very short amount of time. This has been known for over half a century. The only thing which prevents any country (or group of terrorists) from constructing one is getting enough enriched 235U to make it. One needs only to calculate the probability of fission from an incident neutron as a function of energy to determine the volume of a sphere (or any other shape) of 235U required to go supercritical. (It doesn't have to be particularly efficient, so there is no reason to get fancy.) If the data weren't available, a peecee and a few data points would make the task fairly straight forward.
That might be so. I just came across a lot of people who believed that the reason why terrorists cannot get atomic weapons is they cannot find out how to make them. I tried to argue that it was possible, but they persisted. FYI, I believe that you used to be able to get Red Uranium (or is it Red Plutonium?) on the black market. I also saw a programme about a guy who managed to get enough fissionable material from household appliances, to build a small nuclear reactor. He didn't realise just how radioactive it was. Eventually, the police were involved. I believe it cost $750,000 to do a clear up from the radiation.

Stop appealing to emotional arguments. Those have zero merit and are a dead giveaway for a lack of any logic.
Fair enough. My main view is that if you ignore the emotions of it, it is still a moral argument, one that I considered, because I was thinking of going into weapons research after uni, as they seemed to work in cutting-edge technology, and so would appreciate someone who thinks scientifically outside of the box. But judging by what happened to weapons in the past, I realised that any weapons I developed would be left in hands that I felt didn't have the necessary self-control to ensure they would only be used judiciously, and might even be sold to other people and eventually fall into the hands of unscrupulous people. I consider that if I cause a car driver to swerve and have a fatal car accident, then even if the courts don't consider me culpable, I would consider myself culpable. I see myself just as culpable for weapons research, unless I truly consider the consequences, and consider that the benefits to society outweigh the costs. At this point, I doubt that for myself. So I stay out of it. My boss went into working for the MoD, and made the same decision, so he left. Shame, because it's very interesting, and can be quite well paid.

The real secrets of any concern here are designing efficient weapons and creating encrypted interlock schemes to prevent someone from making use of bomb which gets dropped but fails to explode. Even where encryption is concerned, encryption is not considered secure if it depends on hiding the encryption algorithm or the details of the implementation.
Interesting. But that would rely on the encryption system itself being impossible to crack. Suffice to say, it is possible. Fortunately, right now, no-one has yet put a method on the net, at least as far as I know, to crack public-key encryption systems. Problem for me is, I'm fairly sure that someone will do it one day, so I expect that one day all those encrypted systems will be broken. In the meantime, I just take it that G-d has a plan, and that He'll ensure that the terrorists will only get what is in His plan, so if they do get a weapon, and I get killed from it, may it never happen to us, then that was in G-d's plan, and that is the best thing for me. If I didn't think that, I'd be bricking it.

No one has the right to supress knowledge.
I consider that it's still knowledge to know how to kill people. I don't want to show that to people who might use it to unfairly hurt people.

RE msg 121 by abelian:

In my opinion, it would be clearer to say that modern electronics relies almost completely devices on ONE flexible type of device, semiconductor devices, such as the solid state transistor, which were based on quantum theory. It's a subtle difference. It's the difference between saying that vaccines are based on science, and vaccines are based on germ theory. One is a lot clearer than the other.
You seem to get the cause and effect backwards a lot. Quantum mechanics tells you what properties the materials must have to produce the phenomena needed for things like transistors and it also tells you all of the ways to change its properties to create lots of variations so that it's very flexible, as you put it. The choice of materials is dictated by the materials that exist in this universe which have the properties necessary to function as the equations predict. The choice of materials was not arbitrary and semiconductors were not discovered blindly by trial and error. Since there exists no theory which is an alternative to quantum mechanics, quantum mechanics and science are the same thing. Ditto for the germ theory, unless you dispute the existence of microorganisms or their responsibility for infections and disease AND have a better theory which explains germ theory as a subset.
In pool, mechanics tells me what angle I need the cue ball to connect with the red ball to shoot it into the corner pocket. Put another way, mechanics tells me what properties my shot must have (the angle of the connection between the cue ball and the red ball) to produce the phenomena needed (shoot it into the corner pocket), to win a game of pool. But I'd still say that my pool-playing is based on mechanics, even if I didn't know any people who played pool without knowing anything about mechanics at all.

Let's put it another way: we say that A is dependent on B iff we can show that we will never get an example where A is not true and B is true.
So if we cannot find an example where quantum theory is true, but semiconductors don't work, we can say that semiconductors are NOT dependent on quantum theory. But not otherwise.

I think what you are trying to say is that the current design of semiconductors is an EXAMPLE of an application of quantum theory. Ditto for vaccines and germ theory. I accept that.
 INTOART

Joined: 3/12/2008
Msg: 123
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In an infinite universe...
Posted: 10/13/2008 7:39:31 AM

The fact that I don't genuflect at its altar has nothing to do with lack of intelligence.


Nobody "genuflects at its altar". Science is not a religion or a belief system, nor does it have anything to do with "ego" as you so insultingly imply. The scientific method is merely the only valid method that exists for learning about reality, because it is based on repeatable observations (as opposed to fleeting impressions or peexisting ideas.)
 abelian

Joined: 1/12/2008
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In an infinite universe...
Posted: 10/13/2008 9:23:04 PM

Consider the same sphere. But now, imagine that it is made of water, enclosed by a covering of infinitely thin, but infinitely strong plastic.


That is irrelevant.. The paradox concerns surgery on manifolds. There is no such thing as an infinitely strong anything nor an infinitely thin anything. Those kinds of approximations are only useful when your argument doesn't depend on them. In any case, the paradox is a mathematical result, not one that necessarily applies to any physical object.


So I really don't see how it is possible to get more than we started with, even on a theoretical basis.


That's becuse you are trying to build in constraints that aren't part of the theory from which the paradox is a result. Don't do that.


Fair enough. My main view is that if you ignore the emotions of it, it is still a moral argument,


Building weapons is an engineering issue. I wouldn't build weapons either, but I don't see what that has to do with anything.


That might be so. I just came across a lot of people who believed that the reason why terrorists cannot get atomic weapons is they cannot find out how to make them.


I'm a nuclear physicist by training. I don't have to speculate. We're talking about a bomb that explodes, not a fancy one or an efficient one or even a small one. The reason that 5 axis machining centers and other precision machine tools are export controlled is because the difficulty lies in building the equipment needed to produce enriched 235U, not because there's anything secret about what to do with the enriched 235U if all you want to do is make crude bomb. As an aside, all anyone has to do to find quite a bit of information about the relative yields of various fission fragements and which isotopes are most important for making weapons is to look in the atomic mass tables. it's no accident that isotopes which are important for weapons have masses given with precisions to many decimal places.


But that would rely on the encryption system itself being impossible to crack.


No, it doesn't. In fact, it'w well known that no encryption is unbreakable unless the key is at least as long as the plaintext, i.e., a one time pad. We don't need a digression on quantum cryptography here, either.


Fortunately, right now, no-one has yet put a method on the net, at least as far as I know, to crack public-key encryption systems.


Uh, real encryption is not dependent upon whether or not some script kiddie gets lucky and figures out how to break it. If a real encryption scheme like RSA, AES, etc., is broken, it will published in cryptography journals (unless it's broken by some organization like the NSA or MI6.) Breaking those requires solving the problem of factoring large numbers very fast.

But I'd still say that my pool-playing is based on mechanics, even if I didn't know any people who played pool without knowing anything about mechanics at all.


Huh? We aren't talking about playing pool.


I think what you are trying to say is that the current design of semiconductors is an EXAMPLE of an application of quantum theory.


Then I am at a total loss as to what all of the rest of that was about.
 abelian

Joined: 1/12/2008
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In an infinite universe...
Posted: 10/13/2008 9:33:35 PM
Your right knowledge has no morality until that knowledge becomes reality... kinda like VX Gas..


This argument is also specious. The knowledge to make VX gas (or some other chemical compound) is called chemistry. If you don't like how chemistry is used, then elect politicians who are opposed to using chemistry to create chemicals for warfare. Supressing knowledge of chemistry is not going to stop others from discovering it. All you have to do is look at the number of new syntheses for methamphetamine which appear every time the precursers used in a known synthesis become controlled. Those aren't developed by drug company chemists. They are developed by people with a basic knowledge of organic chemistry. Do you plan to outlaw introductory courses in chemistry to prevent the type knowlege required to prevent your example from being the result of studying chemistry in college?
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