Mart Posted January 30, 2005 Posted January 30, 2005 Which bit is the problem? Do you mean by charateristic something like the intersection of the shadow-volume with the ground and by identity as the shadow-volume (and the ground)?
noz92 Posted January 30, 2005 Posted January 30, 2005 I was reading this thread: http://www.scienceforums.net/forums/showthread.php?t=8033and was thinking about multi-universes when this though occured to me. We live in a 3 demensional world. Everything we perceive through our senses' date=' and even things that require instuments to perceive have volume (h,l and w). However, is it possible for object...even other life forms to exist in a different dimensional world, say 2 demention. Say there was a colony of rats with only length and width, but it was impossible for us to percive them, becasue they completely lack height. It's hard for humans to imagine this, as we live in the 3d part of the universe, but could this be true. Could different objects exist in alternate dimension...maybe even in dimensions we have not even thought of yet?[/quote'] Your idea of a 2-D rat colony couldn't work. Any 2-D creature couldn't digest food. Let's just pretend that paper is 2-D (since I can't describe anything 2-D). If the paper rat has a digestive sistem, it would be like cutting it into 2 pieces starting from the mouth, and ending at the butt. It would litterally tear the creature a part.
5614 Posted January 30, 2005 Posted January 30, 2005 just reading that post... i though, is anything truely 2D because it will still by travelling through time (at 1 second per second kinda thing)... so the 2D object is travelling through a 4D world... how many dimensions would a truely "2D" object have?
syntax252 Posted January 30, 2005 Posted January 30, 2005 someone said something about things existing in more that 3 dimentions. I always thought that time was the 4th dimention, but what other dimentions would there be?
Cadmus Posted January 30, 2005 Posted January 30, 2005 someone said something about things existing in more that 3 dimentions. I always thought that time was the 4th dimention' date=' but what other dimentions would there be?[/quote'] To say that time is the fourth dimension is in itself not very meaningful. It is important to state, or at least imply, the domain. There does exist a commonly used domain of modern physics wherein it is considered that there exists 3 dimensions of space and 1 dimension of time, the total of which is 4 dimensions. Do we live in a 3 or 4 dimensional world? Such a question belongs more to philosophy than to physics currently. When you suggest that time is the 4th dimension, you are implying the domain of science that you accept. There are other domains as well. There is currently a trend in physics, among many scientists, to postulate more dimensions of space. There are those who propose 10 dimensions, other propose 11 dimensions, others propose 26 dimensions. These are only the most well-accepted, hypothetically, proposals. It time really a dimension? Is it only 1 dimension? Philosophy has better answers than physics at this point.
ecoli Posted January 30, 2005 Author Posted January 30, 2005 Your idea of a 2-D rat colony couldn't work. Any 2-D creature couldn't digest food. Let's just pretend that paper is 2-D (since I can't describe anything 2-D). If the paper rat has a digestive sistem, it would be like cutting it into 2 pieces starting from the mouth, and ending at the butt. It would litterally tear the creature a part. Sorry...but you have the wrong idea...you description would make sense...if 2d rats ate 3d food. But this wouldn't be the case. In relation to other posts on this thread: There are other theories that in upward of 6 dimensions, there are different curvatures of space-time...so maybe objects existing in these dimension could have the ability to be in two places at once?? Discuss...
Cadmus Posted January 30, 2005 Posted January 30, 2005 Sorry...but you have the wrong idea...you description would make sense...if 2d rats ate 3d food. But this wouldn't be the case. In relation to other posts on this thread: There are other theories that in upward of 6 dimensions' date=' there are different curvatures of space-time...so maybe objects existing in these dimension could have the ability to be in two places at once?? Discuss...[/quote'] I think that you are skirting the bounds of science and tending more toward science fiction when you suggest that some objects live in certain dimensions and other objects live in other dimensions. I think that more common theory is that objects live in all dimensions, however many that is. Our species may not be aware of all dimensions, and so we search for understanding what dimensions exist, but variations in existence are not generally thought to occur in certain dimensions but not in others in any given case.
mrbc19 Posted January 30, 2005 Posted January 30, 2005 I know that in the Elegant Universe, Greene gives a good example of how to understand more than 3 spacial dimensions, I forgot exactly what it was, but I know it enlightened me at the time I read it. If anyone has read it and remembers, could you please post it?
noz92 Posted January 30, 2005 Posted January 30, 2005 Sorry...but you have the wrong idea...you description would make sense...if 2d rats ate 3d food. But this wouldn't be the case. In relation to other posts on this thread: There are other theories that in upward of 6 dimensions' date=' there are different curvatures of space-time...so maybe objects existing in these dimension could have the ability to be in two places at once?? Discuss...[/quote'] How would it eat 2-D food. It has no debth, so how could you have a hole going through it?
ecoli Posted January 30, 2005 Author Posted January 30, 2005 You're still thinking 3 demensionally...
noz92 Posted January 30, 2005 Posted January 30, 2005 A lot of people say that we're 3-D. But if time is the 4th dimension, since we move and are effected by time (we gain entropy), then would that mean that we're 4 dimensional? I would think of something like light as 3 or less dimensional because it isn't effected by entropy (it never changes).
ecoli Posted January 30, 2005 Author Posted January 30, 2005 Liight does change forms...it changes wave lengths
syntax252 Posted January 31, 2005 Posted January 31, 2005 couldn't a 2 dimentional life form get it's energy from light? If so, would that solve the ingestion problems?
Edward Duffy Posted January 31, 2005 Posted January 31, 2005 The whole question of 2 dimensional beings is a good example of how math doesn't necessarily translate to reality. We can imagine 2 dimensional beings, but you'll never meet one. In math I can have 0 apples and you can still take 3 apples from me. You'd have 3 apples, I'd have -3 apples and since they still add up to 0 everything is hunky dory. In reality if I have 0 apples, you're not getting any apples from me. The inability to recognize that just because something is mathmatically correct doesn't make it real leads to such beliefs as the notion that an object that reaches the speed of light takes on zero mass and infinite volume. In actuality an object surpassing the speed of light might as well have zero mass because we can no longer detect it, and it might as well be everywhere (infinite volume) because we can never pinpoint it. The math represents the limits of human perception, not reality.
Sayonara Posted January 31, 2005 Posted January 31, 2005 Do you mean by charateristic something like the intersection of the shadow-volume with the ground and by identity[/i'] as the shadow-volume (and the ground)? His question implied that the thing he was talking about and the thing I was talking about were two different but analogous entities, wheres in fact he was describing a characteristic of the thing that I was identifying.
Cadmus Posted January 31, 2005 Posted January 31, 2005 The whole question of 2 dimensional beings is a good example of how math doesn't necessarily translate to reality. This is an excellent point, and deserves to be emphasized. The inability to recognize that just because something is mathmatically correct doesn't make it real leads to such beliefs as the notion that an object that reaches the speed of light takes on zero mass and infinite volume. Actually, this is not quite correct. In Newtonian physics, nothing but light can reach the speed of light, whereas in relativity everything moves at the speed of light. I think that you mean to say as an object appraoches the speed of light the mass approaches ... In actuality an object surpassing the speed of light might as well have zero mass because we can no longer detect it, and it might as well be everywhere (infinite volume) because we can never pinpoint it. Are you suggesting that objects can move at a speed greater than the speed of light? The math represents the limits of human perception, not reality. Math represents models of nature, yet they are not nature. People who believe that math represents nature, rather than being one way to model nature, are limiting their ability to perceive, as you say.
Mart Posted January 31, 2005 Posted January 31, 2005 Sayonara³, this was the question I asked you Do you mean by characteristic something like the intersection of the shadow-volume with the ground and by identity as the shadow-volume (and the ground)? This was your answer His question implied that the thing he was talking about and the thing I was talking about were two different but analogous entities, wheres in fact he was describing a characteristic of the thing that I was identifying. What stops you answering my simple question with a simple answer? Why do you complicate the situation by referring to something else which is only indirectly connected? Here's my question again Do you mean by characteristic something like the intersection of the shadow-volume with the ground and by identity as the shadow-volume ? Attempt to answer my question in a direct and simple way. You can do it. Try.
Mart Posted January 31, 2005 Posted January 31, 2005 Math represents models of nature, yet they are not nature. People who believe that math represents nature, rather than being one way to model nature, are limiting their ability to perceive, as you say. The problem is that some mathematical models of nature predict outcomes much better than others. So it seems that either the models have some fundamental connection with what they represent or what we take to be nature is in reality our model of nature.
Sayonara Posted January 31, 2005 Posted January 31, 2005 What stops you answering my simple question with a simple answer? Why do you complicate the situation by referring to something else which is only indirectly connected? Here's my question again Do you mean by characteristic something like the intersection of the shadow-volume with the ground and by identity as the shadow-volume ? You can blame that on me posting at two in the morning after doing 14 hours straight of mathematics. The identity is the term 'shadow' (comprising the umbra and pen-umbra), and the characteristics comprise all of its properties (which does include projections due to intersection, yes). The reason I made the distinction was because syntax252 confused the identifying term 'shadow' with the characteristic 'area of lessened light', directly after I pointed out the difference.
syntax252 Posted January 31, 2005 Posted January 31, 2005 In reality if I have 0 apples' date=' you're not getting any apples from me. [/quote'] What if you sold "short" 3 apples? It happens every day on the NYSE.
Sayonara Posted January 31, 2005 Posted January 31, 2005 Presumably you'd be offered something else instead, seeing as he has no apples.
Cadmus Posted January 31, 2005 Posted January 31, 2005 The problem is that some mathematical models of nature predict outcomes much better than others. No disagreement here. Some models are more useful than others. So it seems that either the models have some fundamental connection with what they represent or what we take to be nature is in reality our model of nature. No disagreement here either. Many people confuse their model of nature with nature. For example, many people make such claims as a point is infintely small in 3 dimensions. In other words, they are citing the tenets of the ancient model of nature known as Euclidean geometry as though they are accepting this model as being true about nature. Yet, when I look around in nature, I have never seem anything that remotely satisfies the conditions required by the model. I think that it is useful to remember when making claims about nature which model of nature one is using for reference. This is particularly true when speaking about the speed of light for example. People fight constantly about the speed of light, all the while not recognizing that one person may be referring to the Newtonian concept while another is referring to the concept as it pertains to the theory of relativity.
Mart Posted January 31, 2005 Posted January 31, 2005 You can blame that on me posting at two in the morning after doing 14 hours straight of mathematics. The identity is the term 'shadow' (comprising the umbra and pen-umbra)' date=' and the characteristics comprise all of its properties (which does include projections due to intersection, yes). The reason I made the distinction was because syntax252 confused the identifying term 'shadow' with the characteristic 'area of lessened light', directly after I pointed out the difference.[/quote'] Thanks for the straight answer. Keep it up. It can only do you good! Pen-umbra is one word penumbra (modest help provided) Some people (like me) get edgy when they notice mistakes like the spelling above. It alerts them to the existance of ignorance (not stupidity) in the writer. Stupidity is when you know you're ignorant and either do nothing about it or can't do anything about it. To be very stupid is to not know any of your ignorances. You have made another mistake in the use of the phrase Devil's Advocate on another post to me. It's much worse than a trivial spelling mistake because it shows a lack of understanding of the phrase. I think this is a good example of a form of evidence.
Sayonara Posted January 31, 2005 Posted January 31, 2005 Pen-umbra is one word penumbra (modest help provided) Some people (like me) get edgy when they notice mistakes like the spelling above. It alerts them to the existance of ignorance (not[/b'] stupidity) in the writer. I refer you to post #21, where I first used the word penumbra in this thread. You can ascribe the later hyphenation to the four hours of sleep and blistering headache caused by last night's mathsathon, but I would point out that since pen is a non-native prefix the hyphenation is not incorrect, but redundant. You have made another mistake in the use of the phrase Devil's Advocate on another post to me. It's much worse than a trivial spelling mistake because it shows a lack of understanding of the phrase. I think this is a good example of a form of evidence. Actually, the definition you used is one of two, and it is the less 'correct' one (insofar as anyone cares how the Catholic church organised its bun fights in days of old.)
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now