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Posted Nov 18, '11 at 4:15pm

gamer66618

gamer66618

274 posts

They actually just proved relativity instead of disproving it. They forgot add relativity into the equation when they were calculating it's speed, so once they did, the numbers made sense.
I guess that makes sense... Although I don't learn about neutrinos until February/March time. So I don't have a full understanding of the theory or relativity yet...
 

Posted Nov 18, '11 at 5:20pm

gamer66618

gamer66618

274 posts

No? Nothin? Alright then, how about mercury then eh? Not the planet, I mean the elemental transition element. Wanna talk about that or Bromine, synthetic elements, organelles, breathing system, respiratory system (slightly different), maths, anything?

 

Posted Nov 18, '11 at 5:27pm

Somewhat49

Somewhat49

1,669 posts

Is it possible to have a seeable object (no microscopes) made of pure glucose?

 

Posted Nov 18, '11 at 6:06pm

gamer66618

gamer66618

274 posts

Thats pretty interesting.
Thanks. I'd explain it all, but then it would leave no topic for discussion.

Is it possible to have a seeable object (no microscopes) made of pure glucose?
Yes it is. I used it.
 

Posted Nov 19, '11 at 9:08am

gamer66618

gamer66618

274 posts

Alright then, if nobody is willing to have a conversation about it, then I will answer my own suggestion questions.

No? Nothin? Alright then, how about mercury then eh? Not the planet, I mean the elemental transition element. Wanna talk about that or Bromine, synthetic elements, organelles, breathing system, respiratory system (slightly different), maths, anything?
Mercury is the only transition metal that is a liquid at room temperature and pressure. This is because its outer electron subshell is full therefore it is more difficult to remove the outer electron. Because it most closely resembles the noble gases it has a closer structure because of it therefore it is liquid. Bromine is a holegen. Going down the group there is an increase in volatility and therefore Bromine is a liquid. Organelles are mitochondria, chloroplasts, tonoplasts, vacuoles, plasma membrane, cell wall, plasmodesmata, ribosomes, smooth endoplasmic reticulum, rough endoplasmic reticulum, golgi apparatus, cytosol cytoplasm, nucleus, centrioles and lysosomes. Breathing system your lungs expand. The pressure change causes the air to be sucked in through your trachea, bronchi, bronchioles and alveoli. The wet alveoli with a large surface area causes the oxygen to dissolve into the bloodstream. The Nitrogen which makes up 70% of the air we breath in doesn't affect it at all. You then expel the carbon dioxide. The respiratory system. The oxygen moves along the bloodstream. The cells absorb the oxygen molecules by diffusion. The mitochondria absorbs the oxygen and synthesises ATP which then is used to provide the cells with energy. No one's interested in maths, so I ain't talkin bout it. Somebody reply!
 

Posted Nov 19, '11 at 10:46am

aknerd

aknerd

1,431 posts

air to be sucked

There really is no such thing as suction. Moving on...

I like math(s?)... If I had enough time in my life, I would probably make a thread about cool math things. But I don't, so I guess I'll just post on here.

So, this is something I learned this year which is pretty nifty. As many of you probably know, we run into problems when we try to take square roots of negative numbers. So, as a nice little workaround, we just define the square root of -1 as the number "i"*, an imaginary number. This gives us a whole domain of complex numbers (we call them z's, by convention) of the form z = x + iy, where both x and y are real numbers (so iy is the imaginary part of z, and x is the real part).

This is where things get interesting: in order to keep track of complex numbers, we don't use a number line like we do for real numbers, but a plane (called the complex plane). We represent each point z=x+iy on the plane by its x and y coordinates, just like we would if we were graphing an equation of one variable onto a real graph.

However, something cool we can do with this complex plane is "map" it onto a sphere (in this case called a Riemann sphere). We create a basic bijective, conformal function that takes each point on the complex plane, and relates it to a 3D point on the sphere. Similarly, we take the inverse of the function to map every point on the sphere back onto the plane.

When we do this, we see that all lines through the origin (the point 0,0) on the plane are mapped to circles on the sphere that intersect the north and south poles, IE longitudes.

THIS is the interesting part (I SWEAR). So, the circles intersect each other twice (once at each pole) but the lines only appear to intersect each other once. Because the function we are using is conformal, we know that every intersection on the sphere must be mapped from an intersection on the plane. So, where is the missing intersection on the plane? I'll tell you! It is at the POINT at infinity! You see, in the complex plane, there is no difference between "negative" infinity and positive infinity. I mean, what would infinitely imaginary mean, anyway? So, we consider all the different kinds of complex infinity to just be one point on the plane that all lines must pass through.

So, all non-parallel lines in the complex plane intersect twice, and all parallel lines intersect once. Crazy!

*The interesting this about this definition is that imaginary numbers have no inherit concept of size or polarity (like positive versus negative) the way real numbers do. Think about it: what is i squared -1. But, What is negative i squared? -1. (just like how -2 x -2=4). So, what is the square root of -1? both i and -i. So, every time we define i, we don't know if we are getting negative i or positive i. So we can't say things like -i < i, since, we don't actually know which is which!
 

Posted Nov 19, '11 at 11:09am

gamer66618

gamer66618

274 posts

I like math(s?)...
I'm English. In USA you say math, in England you say maths or mathematics and statistics etc.

There really is no such thing as suction. Moving on...
I know I was just trying to describe the movement of air molecules from an area of high concentration to an area of low concentration inside the lungs when the pressure changes this causes the air to move in. You're right, it isn't suction.

Yeah. I did surds and I also do quadratics and the discriminant. You cannot reach a normal answer on a calculator if you try to square root a negative. However odd number roots (e.g. 3, 5, 7, 9 etc.) do have real numbers that are negative, because if you times a number by itself it would be a negative timesed by a negative. Negatives timesed together give positives. However if you times that by another negative it becomes negative, however if you times it by yet another negative you end up with a positive. Therefore even number roots don't have real number negatives but odd number roots do. I know that from AS-Level maths.
This is where things get interesting: in order to keep track of complex numbers, we don't use a number line like we do for real numbers, but a plane (called the complex plane). We represent each point z=x+iy on the plane by its x and y coordinates, just like we would if we were graphing an equation of one variable onto a real graph.
Did not know that...

Is that degree level? Did you get that off wikipedia, or did you already know it? My maths teacher has done a degree in Mathematics and Statistics and she said that she's worked with imaginary roots and numbers etc. 3 dimensional, eh?

When we do this, we see that all lines through the origin (the point 0,0) on the plane are mapped to circles on the sphere that intersect the north and south poles, IE longitudes.

THIS is the interesting part (I SWEAR). So, the circles intersect each other twice (once at each pole) but the lines only appear to intersect each other once. Because the function we are using is conformal, we know that every intersection on the sphere must be mapped from an intersection on the plane. So, where is the missing intersection on the plane? I'll tell you! It is at the POINT at infinity! You see, in the complex plane, there is no difference between "negative" infinity and positive infinity. I mean, what would infinitely imaginary mean, anyway? So, we consider all the different kinds of complex infinity to just be one point on the plane that all lines must pass through
Wow this is beyond my knowledge... You sure this is not degree or at least advanced level?
So, all non-parallel lines in the complex plane intersect twice, and all parallel lines intersect once. Crazy!
Interesting.
*The interesting this about this definition is that imaginary numbers have no inherit concept of size or polarity (like positive versus negative) the way real numbers do. Think about it: what is i squared -1. But, What is negative i squared? -1. (just like how -2 x -2=4). So, what is the square root of -1? both i and -i. So, every time we define i, we don't know if we are getting negative i or positive i. So we can't say things like -i < i, since, we don't actually know which is which!
Okay now that bit I get. If you are operating with imaginary numbers and roots, then how do you know that it is positive or negative therefore how can you polarise? This is quite complex, just like anything divided by 0 could equal either positive or negative infinite! OMG! So therefore it is difficult to quantify because you don't know when working with imaginary numbers and roots whether you are adding a negative or a positive with a negative or a positive number? More importantly it gets more difficult to determine if you have a negative decimal imaginary number; I'm fairly sure this is degree level, and therefore beyond my expertise, but I don't know because I don't do further maths...
 

Posted Nov 19, '11 at 11:12am

gamer66618

gamer66618

274 posts

Wait, wait, wait... Do you do science and maths or just maths? I'm confused...

 

Posted Nov 19, '11 at 11:39am

aknerd

aknerd

1,431 posts

I'm English. In USA you say math, in England you say maths or mathematics and statistics etc.

That's interesting. I mean, we say statisticS and mathematicS too, so really we should say maths (we do say stats, by the way, and not stat). But it sounds weird... anyway.

Is that degree level? Did you get that off wikipedia, or did you already know it?

Its something I learned/figured out* in my complex variables class, which is pre-graduate level class. I am currently over halfway done with completing my Math major in college. Wikipedia can sometimes be helpful with math, but often their proofs of concepts are very bad, or they assume that the reader has a PhD in math.

*in higher level math classes you have to figure out as many things as you are taught. Which can be both rewarding and annoying.

Wow this is beyond my knowledge.

Well, maybe! But I don't think it is beyond your understanding. If you think of the sphere as a ball placed on the origin of the plane, and then wrapping the plane around the sphere, it kind of makes sense. All of the "edges" of the plane (ie the points infinitely far from zero) would meet at the top of the ball.

Notes that this also implies that all lines can be thought of as circles through infinity.

More importantly it gets more difficult to determine if you have a negative decimal imaginary number


What's really weird is when you compare real numbers and pure imaginary numbers.

For instance, which is greater: i, or 1?

For reasons such as these, we don't try to compare sizes of complex numbers. Instead, we compare sizes of their absolute values, which is just their distance from the origin in the complex plane (just like how with real numbers the absolute value is the distance from zero on the number line). Of course, this mean that all complex numbers on a circle with the same radius centered at the origin have the same absolute size.

(so, to answer my own question, |i| = |1| = |-1| = |-i|).
 

Posted Nov 19, '11 at 12:06pm

gamer66618

gamer66618

274 posts

That's interesting. I mean, we say statisticS and mathematicS too, so really we should say maths (we do say stats, by the way, and not stat). But it sounds weird... anyway.
Yeah, I agree. We say stats too as well as statistics and algorithms.
Its something I learned/figured out* in my complex variables class, which is pre-graduate level class. I am currently over halfway done with completing my Math major in college. Wikipedia can sometimes be helpful with math, but often their proofs of concepts are very bad, or they assume that the reader has a PhD in math.

*in higher level math classes you have to figure out as many things as you are taught. Which can be both rewarding and annoying.
Yeah I don't do variables. I do less complex stuff like integration, differentiation, quadratic, cubics and other polynomials, circles, co-ordinate geometry and surds. BTW: very good on figuring that out! :) I'd've never've guessed that; I'd've been had to've been taught that, no?
Well, maybe! But I don't think it is beyond your understanding. If you think of the sphere as a ball placed on the origin of the plane, and then wrapping the plane around the sphere, it kind of makes sense. All of the "edges" of the plane (ie the points infinitely far from zero) would meet at the top of the ball.
Yeah, weirdly I heard that about theoretical physics at and beyond PhD level using that kind of advanced mathematics in their formidably difficult physics equations (you gotta be good at maths if you wanna be good at physics, ya know?...). That's kinda beyond my knowledge and probably beyond my understanding as well. I prefer biology and I prefer stats to variables within maths (hence why I picked Mathematics and Statistics instead of Decision Maths because even though they otherwise have the same modules they have the last exam as optional between Decision Maths (algorithms, variables etc.) and statistics (exponent function, other things etc.)). Circles through infinity? Hmm...
I have done 3 dimensional coordinate values, but never spherically so. I've done circles and 3D affects, but never combined! As far as I've ever gotten was drawing cuboids! Still a sphere is
area=(2/3 pi r)cubed (i.e. the radius multiplied by pi multiplied by 2/3 all cubed). So you could probably work out the area of the sphere even if it circles round infinite.
For instance, which is greater: i, or 1?

For reasons such as these, we don't try to compare sizes of complex numbers. Instead, we compare sizes of their absolute values, which is just their distance from the origin in the complex plane (just like how with real numbers the absolute value is the distance from zero on the number line). Of course, this mean that all complex numbers on a circle with the same radius centered at the origin have the same absolute size.

(so, to answer my own question, |i| = |1| = |-1| = |-i|).
Well, yeah. I mean if you try to compare x squared to x cubed you not gonna get an answer, know what I mean? You need to figure out the values they stand for to compare them (like 4 and 7 or something...). And you can't compare ionisation energies because of the extreme differences between them; plotting a graph with appropriate scales would be a nightmare! But if you find the "log." (i.e. logarithm) of the ionisation energies, you can plot those points instead and see that the differences lie between changes in the energy shells as one shell is removed, you're closer to the nucleus and the attraction is more and the shielding is less. You learn that sorta stuff as AS-Level Chemistry. So therefore you just compare the distances from the origin. That makes sense...