uncool

Congratulations on saying in a thousand words what one sentence is enough to describe.

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Your numbers are incorrect, sjbouscher. Read Bignose's post. Read the correct answer in post #6. Read the problem. It says right up front that the cow eats the same amount as the duck and goat combined and that the duck and goat eat all the grass in 90 days.

 

You set the problem up incorrect in post #10 and arrived at a nonsense answer. What is the right way to set up the problem?

 

The underlying assumption is that the grass grows at some unspecified linear rate, call this rate r. If the initial height of the grass is h, the height h_0 (the subscript 0 denotes no critters are eating the grass) at time t is [math]h_0(t)=h+rt[/math]. That is assuming no critter is munching on it, of course.

 

This is not a particularly realistic assumption (grass stops growing at some height), but it becomes a lot closer to reality when critters keep the grass trimmed. Suppose some critters are munching on the grass -- the cow and goat, for instance. These critters are going to eat fixed amounts of grass per day. Denote the amount eaten by the cow as c and the goat as g. Now the height as a function of time is [math]h_{c,g}(t) = h+(r-(c+g))t[/math]. The cow and goat eat all the grass in 45 days. In other words, the height is zero at t=45. In math, [math]h+45(r-(c+g)) = 0[/math] or [math]45(c+g-r)=h[/math]. Continuing in this regard,

 

[math]45(c+g-r)=h[/math]

[math]60(c+d-r)=h[/math]

[math]90(d+g-r)=h[/math]

[math]c=d+g[/math]

 

That final equation reflects the given information that the cow eats as much as the duck and goat combined.

 

One thing that makes this problem interesting is that the problem is uniquely solvable even though there are only four equations and five unknowns (c, d, g, h, and r).

That would be because it is effectively a problem in 4 unknowns:

h/c, h/g, h/d, and h/r.

=Uncool-

It will take time for the pattern to be destroyed - the interference pattern is a result of the light propagating. If you place your detector right next to the splitter, only after the appropriate interval will the pattern be destroyed. In the meantime, the person would be unable to detect the difference.

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What are a, b, p, and q?

And why is (C - B) equal to b^n, and (C - A) equal to a^n?

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Length is the measure of how long a object is. So when you say length contraction you mean the object contracts thus the length contracts.

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Merged post follows:

Consecutive posts merged

The same way a clock doesn't measure the time in the universe, the ruler doesn't measure the length.

The best way to say what you are saying is that there is no absolute time, nor absolute length, for any object or event. However, there is a rest length for the object, and as it begins to move, its length contracts.

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Just fyi guys, coberst is an old, old spammer. Look up this exact topic. I've seen it on at least 3 fora I go to. It's apparently on at least 30 of them, according to google.

The idiot rarely returns to his threads - I've only ever seen it 3 times, and with barely any real contributions. Usually he just reposts an old reply when people ask the same questions as others did on other fora, without even trying to do anything new with it. He doesn't discuss anything.

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Gasparri:

The dimension of a manifold (such as the mobius band) is defined as what Euclidean space it "looks like" locally - that is, if you take a small enough neighborhood of any point on a manifold, it will look like R^n for some n, and n is defined to be the dimension.

The mobius band locally looks like 2-space, or a plane - and so is defined to be 2-dimensional.

The whole notion of transluminal speeds is interesting. I have found at least

one case (that implies there are more) where light seems to travel faster than light. This I see as virtual but the fact is the question remains unanswered as far as I know. Here it is, you can plainly see this laid out in black & white

here:

 

Two things are big hangups as they are non entities. These are

Gravity and Time. Neither exist in reality but in the virtual world of the

human mind they do, as mirages that cannot be approached.

 

Gravity is a result, nothing more. It has no entity, no particle, no wave.

No graviton will ever be found by CERN.

 

Time is simply a method of metrication of motion and nothing more.

Motion and time are one in the same thing equally resolvable as

as something they are not. There will be no time travel. A trillion

years ago and 1 day from now are the same instance timewise but

motionwise things are always changing. Obama wants change? Look

at the universe, that's all it is. Change.

 

I await my asschewing by those that 'know' the truth.

As a response to the video:

He is mixing his frames entirely wrong. In the frame of the ships, yes, it would only take one second to cross the distance between them. However, in the frame of the observer, the light would not be going perpendicular to the velocity of the ship - it would have to "catch up" to the other ship, as he seems to say later in the video. If he stopped mixing his frames, the "superluminal" messaging would clearly not exist.

=Uncool-

Z512

Z256*Z2

Z128*Z4

Z128*Z2*Z2

Z64*Z8

Z64*Z4*Z2

Z64*Z2*Z2*Z2

Z32*Z16

Z32*Z8*Z2

Z32*Z4*Z4

Z32*Z4*Z2*Z2

Z32*Z2*Z2*Z2*Z2

Z16*Z16*Z2

Z16*Z8*Z4

Z16*Z8*Z2*Z2

Z16*Z4*Z4*Z2

Z16*Z4*Z2*Z2*Z2

Z16*Z2*Z2*Z2*Z2*Z2

Z8*Z8*Z8

Z8*Z8*Z4*Z2

Z8*Z8*Z2*Z2*Z2

Z8*Z4*Z4*Z4

Z8*Z4*Z4*Z2*Z2

Z8*Z4*Z2*Z2*Z2*Z2

Z8*Z2*Z2*Z2*Z2*Z2*Z2

Z4*Z4*Z4*Z4*Z2

Z4*Z4*Z4*Z2*Z2*Z2

Z4*Z4*Z2*Z2*Z2*Z2*Z2

Z4*Z4*Z2*Z2*Z2*Z2*Z2*Z2

Z2*Z2*Z2*Z2*Z2*Z2*Z2*Z2*Z2

Way more than 10 possibilities.

The way I suggest: Find the element of largest magnitude, and mod the group by it. Repeat until you have the trivial group. The list of orders should be the group itself. Note: You must use the largest-magnitude element, as otherwise, you could be modding out incorrectly.

Guys:

One of the assumptions of relativity is that there are such things as inertial paths. Once you assume that, you can take any inertial path. Then anything moving at the speed of light will be moving at the speed of light relative to any other inertial path.

You can also get the speed of light from Maxwell's equations, which state how fast an electromagnetic wave moves through space (hint: it's at a familiar speed...)

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I've been trying to find the exact definition of a CQF in many places, but I have not been able to actually find it. Does anyone know the exact definition of a conjugate quadrature filter?

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Can't gravity still be used in special relativity, so long as the distortion effects are ignored? That is, you assume that gravity does not affect the speed of light/etc.?

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How does special relativity affect a gravitational field? I'd think that because the radius becomes smaller and the masses become bigger, the field is magnified by a factor of gamma^4. Is that right?

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To Mr. Skeptic

 

It has been said that sarcasm is the last resort of the incompetent. I am sure you are not incompetent or at your last resort, so the sarcasm is not appropriate.

I do agree, sarcasm is the last resort of the incompetent. That is why I use sarcasm much more quickly.

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Hrm...gravitons interact weakly with other gravitons? Because I'd think that would falsify General Relativity in a way - you would be able to distinguish between acceleration and gravity simply by watching the effect on gravitons, wouldn't you?

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Actually, what does happen when you throw a charged particle into a black hole? Doesn't the black hole basically "swallow up" the charge, because the electrical force works through photons?

Shouldn't it also do that for gravitons, if they exist? As in, wouldn't this be a proof that gravity is a change in spacetime rather than by particles?

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You have a star. Photons travel out one side of the star at c. Photons travel out the other side at c. If you are a lucky quark that somehow got to hitch a ride on one of these photons, surfing through the universe, then the photons travelling in the other direction would be travelling at double c relative to you. As swanson pointed out, they would not be travelling faster than the speed of light, except via special relativity.

That's not even correct - if you are a quark traveling very close to the photon relative to the star (because nothing can travel with the photon, not even a viewpoint), the other photon would still seem to be traveling at c. This is because your system has different lengths and different time intervals than the original system - as shown by special relativity. This is actually the first thing you find in relativity - the second postulate: anything going at the speed of light in one inertial frame is going at the speed of light in any inertial frame.

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Sorry, just in general don't like giving out my e-mail. Think you could at least make your proof somewhat more formal?

And to use latex, just use the [ math ] [ / math ] things without the spaces.

[math]\frac{1}{2}[/math]

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Adib, think you could latexise it? I cannot read what you wrote.

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Not quite - P(0) is not (n-1)!/n!. For example, P(0) for 4 is 3/8, not 1/4. The actual answer is:

1/1! - 1/2! + ... + (-1)^(n - 1)/n! (iirc). See

http://en.wikipedia.org/wiki/Derangement

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The series for e^x is

1 + x + x^2/2 + ... + x^n/n! + ...

So the series for e^(-x^2/2) is

1 - x^2/2 + x^4/4 - x^6/(3!2^3) + ... + (-1)^n x^(2n)/(2^n n!) + ...

Therefore, the series for erf(x) is

C + x - x^3/6 + x^5/20 - x^7/(7*3!*2^3) + ... + (-1)^n x^(2n + 1)/(2^n n! 2n+1) + ...

C = 0, so the series is

erf(x) = x - x^3/6 + x^5/20 - x^7/(7*3!*2^3) + ... + (-1)^n x^(2n + 1)/(2^n n! 2n+1) + ...

=Uncool-

swansont

 

The following quotation is taken from "Concepts of Mass"

 

If it were possible to define the mass of a body or particle on its own in purely kinematical terms and without any implicit reference to a unit of mass, such a definition might be expected to throw some light on the nature of mass.

 

Please compare that with my explanation of mass.

...there's nothing to even compare. The quotation simply is saying it's nice to have an explanation. That's it. There's no "compare," there's no "contrast," there's nothing.

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Do you mean factoring? That is an NP problem, and finding a way to solve that in polynomial time is worth big $$$.

Nah, I mean actually finding a prime. I know the usual methods today are simply finding a pseudoprime, which is very likely to be prime, by checking fermat's little theorem. However, that doesn't guarantee the primality of the number found.

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Just toying with ya. A trivial polynomial isn't much of much value. I don't think Jone's polynomial has much more than academic interest, either It was an interesting offshoot of the work done on Hilbert's tenth problem. On the other hand, the polynomial-time AKS primality testing algorithm (for-the-masses review and the paper itself) won immediate accolades and awards, including a nomination for the Fields medal.

Yeah...now that's an interesting find - that prime testing can be done in poly time of the log of the prime. What is the current least prime-finding algorithm so far?

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I'm sorry. I thought you might want to add a polynomial that actually does find primes to your spreadsheet. I see now that your spreadsheet is reserved for polynomials that purport to find primes, but fail to achieve that objective.

 

 

The polynomial f(x)=3 generates a prime for all x.

Gah...bad terminology. I meant to say that it wouldn't work for any nontrivial (nonconstant).

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