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#276 Re: Help Me ! » Shift of Geometric Series » 2008-10-31 23:31:22

roll

The term (j-1)q[sup]j[/sup] when j=n+1, or the term iq[sup]i[/sup] when i=n

You see, I did the index shifting j=i+1, and I did the shifting of summation interval correspondingly, which may cause some confusion.

#277 Re: This is Cool » Zero !!! » 2008-10-31 23:22:56

Ricky wrote:

The only real difference is that the mathematican proves arbitrary difference whereas you have some magical value that is "small enough".  Praytell, what precisely is that value?

Ricky wrote:

George, I've said a million times that when we say "approaches infinity", we mean the value gets arbitrarily close as N gets sufficiently large.  N only need exist, it does not have any restriction on the value.

Ricky, I do not have a physical evidence that all that approximation has a stop point. I do have some for particular formulas which in fact deals with a multiple of smallest divisions - the formula to calculate mass and electricity, for example

And what is more, I have logical evidence that the concept "arbitarily small" embeds "infinitesimal" as an essential part and hence is paradoxy and hence cannot exist even before any physical evidence is found.

Let's define a pair of quantities, either one is larger than the other at the same time. I do not need to list all possible two quantities to convince you that such pair cannot exist through pure logic. And do you buy it? Do you just say that because I cannot find all pairs of quantities to present them in front of you so that you believe there is some room for such a paradoxy pair to really exist?

There is priori knowledge beyond empirical knowledge, and this is LOGIC. You are free to make assumptions and make definitions, but your assumption and definition cannot be self-contradictory.

And the proof of potential infinitesimal containing real infinitesimal was the main topic of my essay, the gravity break down was just the appetizer. I regret not putting the argument of priori knowledge in it to present it more convincing.

And forgive me for not sharing the proof just for now. I can give a hint, my proof only use rationals, or fractions, without even a touch on Reals, and it doesn't have to, since Reals are found on the assumption of all fractions' existence.

#278 Re: This is Cool » Zero !!! » 2008-10-31 04:49:38

TheDude wrote:
All_Is_Number wrote:

It seems you don't understand Newtonian gravity. The model doesn't break down; it was never intended to be used at d=0. Such a scenario cannot exist on the macro-scale for which Newton created his model. Of course that doesn't change the fact that mathematics, at our current level of understanding, breaks down when we attempt to divide by zero.

This is true, but it's also the reason I ask why you consider it to be a mathematical breakdown when the model isn't even intended to be used at such small distances.  Yes, under certain situations that the model was never intended to be used it requires the impossible (division by 0), but I fail to see why you would blame it on the shortcomings of math rather than the shortcomings of the model.

Well it is like this. When one time maths model fail to explain reality, we say it is coincidence. When again and again this kind of thing happens, are they just coincidences? There could be some fundamental reason that maths isn't able to universally describe university, and the reason is its logic flaw.

#280 Re: Help Me ! » Shift of Geometric Series » 2008-10-31 02:25:15

How about now? I found the term q[sup]n+1[/sup] needs a coefficient n. And thank you for pointing that out.

#281 Re: Dark Discussions at Cafe Infinity » Debate #001: Is math a science? » 2008-10-31 02:03:49

Just like the neo-liberalism and market-fundamentalism. We haven't come up with a substitute, so folks just bear with it and listen to our preach it is the truth we know so far even we know its assumptions are ungrounded.

#282 Re: Dark Discussions at Cafe Infinity » Debate #001: Is math a science? » 2008-10-31 02:01:46

People will take the result of a theory based on wrong assumption for granted and then for a long time accidentally "discover" the fault in reality, how smart!

#283 Re: Dark Discussions at Cafe Infinity » Debate #001: Is math a science? » 2008-10-31 01:59:12

. Just as Euclidean geometry is "wrong" in the context of the real world, so are Newtonian mechanics. Yet, both are still extremely useful

Well, it doesn't mean we use them without recognizing their faults, and without knowing how they coincidentally discribes things right in some cases, but will definately fail in other cases.

If the assumption is wrong, the theory is doomed to fail in some cases, even if it looks right, funcitions well in other cases. History acknowledges this fact and people's ignorance very often.

#284 Re: Dark Discussions at Cafe Infinity » Debate #001: Is math a science? » 2008-10-31 01:53:47

Ricky, since maths is free of examination of reality, I wonder- is it free of examination of logic as well?

Can mathematics use logic when it needs it, and throw it away when it gets in the way?

then indeed it is the queen, very powerful and very inconstant.

Can a paradox be a legal concept in mathematics? And how should mathematicians regard it? What need they explain to outsiders who just need to use mathematics in reality? Do they say, you see, there is a flaw here, but we like it ,we really love it, it is the only way we think we come up with it, take it or leave it?

If you are a customer, what will you feel when a sales representitive says something like this about a car?

#285 Re: Dark Discussions at Cafe Infinity » Independence of Kosovo » 2008-10-31 01:43:56

before 100 years,their parents said to them that in that time,there were any serb around.Serbia has expulsed albanians from their houses,because that regions is a riched long plain  because of it's river,and tool albanians prorietary and give them to serbs wich tehy placed in the albanians proprieties.This is an "ethnic  cleaning

Again, before 200 years, what happened in America? 50 years ago, what happened in Palestan? You see, there is no justice in land. You can think it is just for you to own the land, while the other think they can own it too. Sometimes the native win, while other time the immigrants win. There is no justice whatsoever in this zero-sum game, everybody says they are right. What's behind is the power rules.

In this sense, I don't believe the international law, which is just conciliation by big powers.

#286 Re: Dark Discussions at Cafe Infinity » Independence of Kosovo » 2008-10-31 01:39:00

Okay, thanx for sharing your experience. I trust you. But again, you think it is for justice. Ethnic violence happens almost every day in this planet, totalitarian regime rules every day too. You may be the lucky one who gets attention because of geographic importance.

#287 Re: Help Me ! » Shift of Geometric Series » 2008-10-31 01:24:43

This is to compute the weighed average life of maturity by discount value for Annuity.

An Annuity gives you A amount of every year.

Discount "all" of them to now gets you A/(1+r)+A/(1+r)[sup]2[/sup]+...=A/r

And the weighed average life is (1A/(1+r)+2A/(1+r)[sup]2[/sup] +...)/(A/r) = (1+r)/r

#289 Re: Help Me ! » Shift of Geometric Series » 2008-10-31 00:38:20

Oh I got it. Just deduct the first term and get substraction.

#290 Help Me ! » Shift of Geometric Series » 2008-10-31 00:35:00

George,Y
Replies: 8

Just curious, can anyone come up with the answer to the series sum:

(0<q<1)

?

#291 Re: Puzzles and Games » How much would you need to invest? » 2008-10-31 00:32:28

Post 5 is correct. Both the formula and the justification.

#292 Re: This is Cool » All Piecewise Defined Functions Unnecessary? » 2008-10-31 00:22:51

In fact, heaviside function is more often used.

H(x-t)=1 when x>=t, =0 when x<t

#293 Re: Dark Discussions at Cafe Infinity » Independence of Kosovo » 2008-10-30 19:07:02

started violence in albian people

well officially it could be that Serbs started violence, but it may just as the same as the claim that Indians attacked whites in America.

I just need to remind you some group of people are prone to start violence in cordiance under the same rligion basis. This can happen in a large scale, as we observe in Indonesia Massacre, or in a small scale, local bully basis.

And above all, history is written by men. The source may determine its view point. Wars often start with good reason, but often than not, a war is a war, good reason is just one point. Remember the invasion to Greece? To establish a totalitarian government in order to fight communism? Remember the long history of totalitarism in Spain long after the WWII is over? These were under "good reasons". And ironically, Ben Laden was trained by US Intelligence Agency in 1970's during Afgan war, terrorist's technique, how to bomb, was taught to them. and they started their drug business ever since their start. But Uncle Sam just torlarated them, under "good reasons".

Saudi Arabia is authoritarian, but is never considered a threat, while Iran is democratic (at least more deomocratic than the former) but considered evil. But I will never be suprised that some day media (CNN, CNBC, BBC) will cover a small incident in Iran in a large scale for 1 month and for some "good reason", Iran is invaded. And I will never buy it, small things are often excuses, a country wouldn't be that noble to help out on the risk of their own soldiers, they have done the calculation already but won't show it. They often seek their interest or power under a noble excuse.

#294 Re: This is Cool » All Piecewise Defined Functions Unnecessary? » 2008-10-30 18:47:06

|x| is piecewise defined
Here is the point, dude.
Deducting others to this one doesn't necessarily make the case simpler.

#295 Re: This is Cool » Zero !!! » 2008-10-29 14:16:21

I personally believe that mathematics is a description of a pure universe rather than our real one, and that our real one is an approximation to that other universe.  But to me, existence in the pure universe means that it does indeed exist.

I got what you mean, Ricky. Sigh....

#296 Re: This is Cool » Zero !!! » 2008-10-29 13:08:14

This is pretty much exactly what an analyst means when he says "as n goes to infinity".
I am just very curious Ricky here do you mean n really gets to infinity?
How about it never does so the series {0.9, 0.99, 0.999, ...} doesn't gets to 1 anyway?
when the difference is {0.1, 0.01, 0.001, ..., 1/10^n, ...}

Don't invite your Real number friend, Ricky. You know perfectly a Real number is nothing but restating a series. It defines the problem, rather than solving it.

“√3 is thus only a symbol for a number which has yet to be found, but is not its definition. This definition is, however, satisfactorily given by method as, say
(1.7, 1.73, 1.732, …)”
   G. Cantor 1889

#297 Re: This is Cool » Zero !!! » 2008-10-29 12:57:15

This is pretty much exactly what an analyst means when he says "as n goes to infinity".
But not. I deny indefinate increase in most times or indefinite decrease in all times. I have a stop point while the above has not.

Hmm, physics can fail, but mathematics cannot. Mathematics is perfect, the only imperfection is the reality. Even when they do not meet, it is other that should change but mathematics. Good point!

I guess you can start a religion, Mathematicism, Ricky. Don't know if the ancient Greeks agree with you if their souls live to today.

#298 Re: This is Cool » Zero !!! » 2008-10-29 12:46:23

Then you accept the existence of infinity in mathematics because it allows you to accomplish things?

No, I accept N grows larger to an extent, but not further larger, or epsilon grows smaller to an extent, but not further smaller. I accept just throwing off the error term since its impact is minimal.
I accept spending money doesn't mean I accept spending more and more endlessly. You distort the point.

"by observation, it wasn't handed down by god."
Ha, what is handed down by god? Your infinity?

You're also assuming gravity functions continuously at 0, which of course does not have to be the case (considering that "gravity" doesn't make sense at d=0).
You are again trying to block my premise. My proof is against gravity formula is global to 0.
And very funny, if you agree it does not exist at zero, can you give a distance where the formula fails? Do you want to claim it is valid everywhere but just not 0? You are playing a dodge ball. And  good news for me is nature denies the above assumption.

Even at very close distance, the formula is plausible because there is doubt whether such huge force can be at balance while the energy of the universe is limited.

#299 Re: This is Cool » Zero !!! » 2008-10-29 12:36:57

it will be like
0 d/2 d
G 4G G

thus from 0 to d/2, G is increased to 4G
but from ∈ to d/2, ∈>0, we know  it is decreasing
Uh hah, how does this happen? Where is the darn turning point?

Moreover, I can prove G(0) is not smaller than any number. And I think you don't need me to do so, do you?

Thus it is fair to conclude G(0)>any positive number, which is infinity.
Well if you only think infinity is a symbol ∞,
you don't really what it means, Ricky. And of course you assume I cannot prove out a symbol ∞.
It has a meaning beyond its name.

#300 Re: Dark Discussions at Cafe Infinity » Fake Science ramphant in commercials » 2008-10-29 12:28:19

Even when I assume you meant "in most cases" or "for the average person", you're still making a statement and not providing any evidence.

Again, I do not have the funding to hire subjects to come up with how much percent.

"Try it for yourself" just doesn't hold up.  One case does not prove the rule.
But again, one case can prove the one case. Well a gross rule not.

Indeed if there is minimal interaction between your breath and the soft pallet (which I have no idea how much of a smell gets carried, nor how you could measure it), then it wouldn't affect a thing.

Here is where you start your assumption, Ricky. How do you conclude the "minimal interaction" between breath and soft pallet? I think it is as much as, if no more than, the interaction with the upper tongue. It's just arguing the ceiling hasn't been blown by wind while the floor has. And again, upper pallet is at the door to nose system, bearing more breath in normal nose breathing.

""I saw it, therefore it's true," just doesn't cut it"
Good point, Ricky! But again, "I haven't seen it, therefore it's not true" is ignorant as well.

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