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by Eebster the Great
Sat Apr 24, 2010 7:28 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

Even if there's nothing to observe (you're in a box), you still must know that you are travelling slower than your acceleration suggests? Can you really blame it on the Lorentz transformations even though you don't know how fast you're actually travelling... just that you're accelerating? How fast ...
by Eebster the Great
Fri Apr 23, 2010 5:57 pm UTC
Forum: Logic Puzzles
Topic: The Period Numbers
Replies: 47
Views: 6833

Re: The Period Numbers

I read through this thread and am totally baffled. Was the mention of an "American friend" supposed to refer to the different spellings of Aluminum? A reference to Americium? I really don't get it. You are supposed to call an American friend: USA telephone area codes , e.g. Alumunium = Al...
by Eebster the Great
Fri Apr 23, 2010 5:55 pm UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

It is the kind of acceleration that changes direction, not raises speed. Uh, the "kind of acceleration" is irrelevant, I am talking about speed, not acceleration. There are many distant objects that we can currently see, because when the light was emitted, they were within our observable ...
by Eebster the Great
Fri Apr 23, 2010 5:51 am UTC
Forum: Logic Puzzles
Topic: The Period Numbers
Replies: 47
Views: 6833

Re: The Period Numbers

I read through this thread and am totally baffled. Was the mention of an "American friend" supposed to refer to the different spellings of Aluminum? A reference to Americium? I really don't get it.
by Eebster the Great
Fri Apr 23, 2010 5:40 am UTC
Forum: Logic Puzzles
Topic: Given that you have a brother...
Replies: 41
Views: 7336

Re: Given that you have a brother...

It is slightly more likely that you are male. There is only one case where the gender of one sibling affects the gender of another, identical twins. Not only this, but some people are more inclined to have children of a particular gender, whereas nobody is more inclined to have an equal ration of s...
by Eebster the Great
Fri Apr 23, 2010 5:03 am UTC
Forum: Logic Puzzles
Topic: The Arctic Explorers
Replies: 9
Views: 2138

Re: The Arctic Explorers

I've seen this one before. (It was "lost at sea" and "albatross soup", but your version actually makes more sense). Anyway, as these types of puzzles go it seems pretty reasonable. Why do you feel it's stupid? Have you heard other ones like this? "Two lovers laying dead in ...
by Eebster the Great
Fri Apr 23, 2010 4:31 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

BlackSails wrote:You are always moving faster than c with respect to a great number of things. You just cant see these things.

To the contrary, we see many distant objects with recession velocities greater than c.
by Eebster the Great
Thu Apr 22, 2010 6:31 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

BlackSails wrote:And if you break quantum mechanics, you can violate the no-cloning theorem and send information via entanglement.

I seem to remember there were special lodestones used to communicate in the His Dark Materials trilogy that basically did this.
by Eebster the Great
Tue Apr 20, 2010 9:38 pm UTC
Forum: Science
Topic: Could quantum computers generate random numbers?
Replies: 32
Views: 3906

Re: Could quantum computers generate random numbers?

I guess the question really is whether you are worried that a hacker with a huge supercomputer is willing to devote a large amount of her life to trying to crack your keys. If not, your native CSPRNG is probably fine. Really, I think this is mostly paranoia.
by Eebster the Great
Tue Apr 20, 2010 9:31 pm UTC
Forum: Mathematics
Topic: Trig challenge
Replies: 20
Views: 2038

Re: Trig challenge

I didn't even realize there were algebraic real numbers that could not, even in principle, be expressed in the manner I intended (without imaginary numbers). I kind of thought that was what "algebraic" implied.

I guess not.
by Eebster the Great
Tue Apr 20, 2010 6:16 am UTC
Forum: Science
Topic: Could quantum computers generate random numbers?
Replies: 32
Views: 3906

Re: Could quantum computers generate random numbers?

The best way to generate random numbers is rolling dice. Seriously, why go to such great lengths for other RNGs? Or if you really need thousands of bits, just measure movements of the read/write-head or something that computers do quickly; you don't have to go around buying expensive equipment and m...
by Eebster the Great
Tue Apr 20, 2010 5:51 am UTC
Forum: Mathematics
Topic: Trig challenge
Replies: 20
Views: 2038

Re: Trig challenge

Can you also find sin pi/7 or sin pi/9? C.F. Gauss says "No". A regular n-gon can be constructed with compass and straightedge if n is the product of a power of 2 and any number of distinct Fermat primes. Yeah, I guess not. That shouldn't be necessary for my solution, though, as I put the...
by Eebster the Great
Tue Apr 20, 2010 5:08 am UTC
Forum: Mathematics
Topic: Trig challenge
Replies: 20
Views: 2038

Re: Trig challenge

Also, I dont know what you did, but wolfram|alpha gives me a closed form solution. There is of course, the trivial solution \sin(\frac{\pi}{180})=\frac{e^{\frac{-i*\pi}{180}}-e^{\frac{i*\pi}{180}}}{2i} , but thats cheating since e is trancendental. The solution wolfram gives is \frac{-1}{2}...
by Eebster the Great
Tue Apr 20, 2010 1:19 am UTC
Forum: Mathematics
Topic: Trig challenge
Replies: 20
Views: 2038

Trig challenge

K, this is a tough one. Find and prove the exact value of [imath]\sin \frac{\pi}{180}[/imath] (i.e. the sine of one degree), expressed using only a finite number of integers and the operations +, -, *, /, and ^, in simplest form.

Yes, this is possible. No, Wolfram|Alpha will not help you out here.
by Eebster the Great
Sun Apr 18, 2010 5:10 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0727: "Trade Expert"
Replies: 172
Views: 40897

Re: “Trade Expert” discussion

... *cough* pedant *cough* .... That would be true, but only from the point of view of where you are on the graph of interconnected computers. From a geographical point of view, it doesn't make much lemon curry. (Ignoring, of course, the geographical correlation.) A better question would have been ...
by Eebster the Great
Sat Apr 17, 2010 5:12 pm UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

Yakk wrote:
Eebster the Great wrote:
lavina wrote:But there is an indirect way of testing it. If the universe as we know it has a spin on its movement, it could be one way of corroborating the theory.

Um, how are we supposed to test that?

Add up the spins on the components!

lol
by Eebster the Great
Sat Apr 17, 2010 5:11 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 0727: "Trade Expert"
Replies: 172
Views: 40897

Re: “Trade Expert” discussion

Since this has begun to drift onto the topic of bad tech understanding in general, here's one from my great aunt (who had mild Parkinson's at the time, and just two days ago from today broke her hip :(). She had somehow heard about some British students in an exchange program that had come to the J...
by Eebster the Great
Sat Apr 17, 2010 4:55 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

lavina wrote:But there is an indirect way of testing it. If the universe as we know it has a spin on its movement, it could be one way of corroborating the theory.

Um, how are we supposed to test that?
by Eebster the Great
Sat Apr 17, 2010 4:54 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0727: "Trade Expert"
Replies: 172
Views: 40897

Re: “Trade Expert” discussion

I hate when teachers write "www.example.com". It turns out that this actually works, which somewhat surprised me, because the text of the page begins: You have reached this web page by typing "example.com", "example.net", or "example.org" into your web browse...
by Eebster the Great
Thu Apr 15, 2010 11:53 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 0727: "Trade Expert"
Replies: 172
Views: 40897

Re: “Trade Expert” discussion

That's a good point, perhaps I should call it a virgule instead? :thoughtful That could still be potentially confusing, as "virgule" is French for "comma" (and also because nobody will know what you're talking about). Maybe "slant" is a better way to go. But really, wh...
by Eebster the Great
Thu Apr 15, 2010 11:43 pm UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

Hi! What do you guys make of this? http://news.nationalgeographic.com/news/2010/04/100409-black-holes-alternate-universe-multiverse-einstein-wormholes/ The reason I'm posting this here is because of the following quote: "'What is new here is an actual wormhole solution in general relativity th...
by Eebster the Great
Thu Apr 15, 2010 5:32 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0727: "Trade Expert"
Replies: 172
Views: 40897

Re: “Trade Expert” discussion

Here, in Germany, people like to say "minus" for hyphens in web addresses. They're just too lazy to say "Bindestrich" :| Well, the official name for the character is "hyphen-minus," because it is essentially a stroke of intermediate length between the two and used for ...
by Eebster the Great
Thu Apr 15, 2010 3:19 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0727: "Trade Expert"
Replies: 172
Views: 40897

Re: “Trade Expert” discussion

The punctuation mark was not introduced until 1960, for the express purpose of computer programming ... Citation needed. I've been casually and cursorily researching the history of the backslash since soon after this thread started. I have found no hard evidence for or against its existence prior t...
by Eebster the Great
Wed Apr 14, 2010 10:15 pm UTC
Forum: Individual XKCD Comic Threads
Topic: 0727: "Trade Expert"
Replies: 172
Views: 40897

Re: “Trade Expert” discussion

I have seen people mention that the backslash is never used outside of computers. Which raises an interesting question, because in my "abstract math" class, we are covering the basics of set theory. And we use the notation A\B to represent a set of all objects in A that are not in B. Now ...
by Eebster the Great
Wed Apr 14, 2010 4:53 am UTC
Forum: Individual XKCD Comic Threads
Topic: 0727: "Trade Expert"
Replies: 172
Views: 40897

Re: “Trade Expert” discussion

This bothers and confuses me. It bothers me, because of all times to misspell something, a URL is arguably the worst. You could conceivably misdirect people this way (in fact, this probably happens sometimes). It confuses me because backslashes are almost never used. Really, the character hardly eve...
by Eebster the Great
Mon Apr 12, 2010 9:13 pm UTC
Forum: Mathematics
Topic: Favorite math jokes
Replies: 1452
Views: 468467

Re: Favorite math jokes

pernero wrote:Made this up right now:

What do you call a graph where every vertex is visible through your pants?

A Camel-Tonian Graph.

Oh God . . .
by Eebster the Great
Mon Apr 12, 2010 4:24 am UTC
Forum: Serious Business
Topic: Why shouldn't we kill off a large percentage of the Earth?
Replies: 198
Views: 28884

Re: Why shouldn't we kill off a large percentage of the Eart

You mean the vegans that you can spot just by looking at them because their body is eating their own muscle mass to get what it needs? As for olive oil and legumes etc.. you are on 0.07hA remember. Do you even know any vegans? Or are you just intentionally lying to make a point? As for the land req...
by Eebster the Great
Sun Apr 11, 2010 11:10 pm UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

Thanks for all the replies, however I have to say I still do not feel any the wiser. I am happy to accept that I am missing something, that is why I asked the question. Your system by contrast, can be reversed under the much less stringent "reverse all changes". No, that is not what I am ...
by Eebster the Great
Sat Apr 10, 2010 9:22 pm UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

Give me a real world example where I can fully reverse a physical process, get back all the energy and undo all the change - and this is science so I want an experiment that I can reproduce. If you want a thermodynamic experiment, the Carnot cycle is a good example. But really, almost all fundament...
by Eebster the Great
Sat Apr 10, 2010 1:54 am UTC
Forum: Serious Business
Topic: Why shouldn't we kill off a large percentage of the Earth?
Replies: 198
Views: 28884

Re: Why shouldn't we kill off a large percentage of the Eart

For example, the fundamental limit for food production is not ".5 hA per person" like you suggest, or .22 hA per person like we use now, but your number of .07 hA a person, in which case our current land usage would supply 21 billion people, and all arable land would supply 586 billion pe...
by Eebster the Great
Sat Apr 10, 2010 1:32 am UTC
Forum: Language/Linguistics
Topic: Think Before Naming Your Child
Replies: 1622
Views: 327229

Re: Think Before Naming Your Child

My parents luckily did rethink their initial plan to name me "Dor" (they might have spelled it differently, the point is it sounds like "door"). They considered this because one had a grandfather named Theodore, and the had one named Isadore(not sure that was how it was spelled....
by Eebster the Great
Fri Apr 09, 2010 1:00 am UTC
Forum: Serious Business
Topic: Why shouldn't we kill off a large percentage of the Earth?
Replies: 198
Views: 28884

Re: Why shouldn't we kill off a large percentage of the Eart

I don't have a cite at the moment, but I'd be willing to say theres a good chace that Grass->chicken->egg-> human is possibly more efficient than spinnach -> human I'm not exactly sure what you mean by "efficient," but typically about 90% of the energy input is lost in each successive ste...
by Eebster the Great
Thu Apr 08, 2010 5:18 am UTC
Forum: Serious Business
Topic: Why shouldn't we kill off a large percentage of the Earth?
Replies: 198
Views: 28884

Re: Why shouldn't we kill off a large percentage of the Eart

This seems fairly reasonable so far, although I should mention that non-arable land can be and often is turned into arable land. The estimate of total arable land that I used included non-arable land that can be transformed in to arable land such as forests. However, the large scale removal of fore...
by Eebster the Great
Thu Apr 08, 2010 12:24 am UTC
Forum: Serious Business
Topic: Why shouldn't we kill off a large percentage of the Earth?
Replies: 198
Views: 28884

Re: Why shouldn't we kill off a large percentage of the Eart

Based on what? Sorry, I should have gone a bit more in depth (this is SB after all :lol:). I should mention that the statement is only true if the population growth trend and consumption trend hold true. The variables: Total Arable Land on Earth - 31-41,000,000 km 2 This is an estimate which includ...
by Eebster the Great
Thu Apr 08, 2010 12:05 am UTC
Forum: Language/Linguistics
Topic: Think Before Naming Your Child
Replies: 1622
Views: 327229

Re: Think Before Naming Your Child

Just go with Sebastian. That name is sweet.
by Eebster the Great
Tue Apr 06, 2010 8:56 pm UTC
Forum: Serious Business
Topic: Why shouldn't we kill off a large percentage of the Earth?
Replies: 198
Views: 28884

Re: Why shouldn't we kill off a large percentage of the Eart

I can't take resource depletion seriously. I'm sorry, but I can't. If we EVER get to the point where we completely overcome the Earth's ready supply of a certain Resource (where Resource is ANY THING NECESSARY for the continued existence of our eternal 'quality of life') to the point that the Earth...
by Eebster the Great
Tue Apr 06, 2010 1:57 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

This should be a simple question, and one I'm curious as to whether my suspicions are correct. Does a particle that emits light (say the filament in a light bulb) lose mass as it's emitting light? Can you state some examples of why it does or does not / evidence that we may see, but not notice it f...
by Eebster the Great
Sun Mar 28, 2010 12:28 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: RELATIVITY QUESTIONS! (and other common queries)

Aren't there some cute string theory models that make our universe a Brane in a higher dimensional space, and model the big bang as a collision bewteen two Branes? Yes, a cyclic model, in which the extra large dimensions were extremely warped, so that gravity still seemed to behave according to an ...
by Eebster the Great
Fri Mar 26, 2010 3:05 am UTC
Forum: Serious Business
Topic: Why shouldn't we kill off a large percentage of the Earth?
Replies: 198
Views: 28884

Re: Why shouldn't we kill off a large percentage of the Eart

May I ask what your definition of "over" and "under" populated is? A country is overpopulated if its land is unable to support its population, regardless of the political and economic situation. By this definition, Las Vegas is overpopulated, but India is not. A more useful defi...
by Eebster the Great
Fri Mar 26, 2010 2:36 am UTC
Forum: Science
Topic: Miscellaneous Science Questions
Replies: 2870
Views: 657268

Re: Common Questions

Free-falling objects experience the same acceleration no matter their mass. Neglecting air friction. Just to be perfectly correct... I've never understood this. Is it because the extra inertia an object has due to having more mass cancels out the increased pull of gravity? Exactly so. The gravitati...

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