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JaKiri

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Posts posted by JaKiri

  1. It would, ignoring air resistance, be moving at some 80m/s, which isn't shabby.

     

    It would, in fact, just go splat.

     

    Taking air resistance into account, what YT said. It has an extremely significant effect for critters of that size.

  2. This thread is obviously a metaphor for the debate over Nietzsche's concept of the will to power in opposition to the nature/nurture argument.

     

    Batman is the superman, the ubermensch, and as such choosing Spiderman is just an expression of the author's embedded belief in a system which tells individuals that they fail because they lack some gift, some artificial crutch, a system which indoctrinates its young to believe that only those who are predetermined, or lucky, can strive to be the best; is it any coincidence that the vast majority of these "super heroes" (for they are not mere "men") arise form America, a country which represents itself as a meritocracy, yet only uses this to twist perceptions, to make its populace believe the truth of that statement when the reality is more of an unbalanced system than even feudal Europe.

     

    Plus Batman beat Superman in Alan Moore's The Dark Knight Returns, and Superman's a lot tougher than Spiderman.

  3. Is time a consequence of movement? this thought struck me as i was walking to work yesterday. if the universe was static there would be no need for a fourth coordinate to specify time. although impossible to be static in the quantum realm, theoretically it everything was static would time move foward? and could you tell the difference between the two states?

     

    If there was no motion, there would be no definition of time, because our definitions of time, and length, and the like are empirical approximations of what we perceive.

     

    Of course, this is somewhat impossible.

  4. If I say that at C2 mass exhibits the same characteristics as energy

     

    You'd be wrong. You're misinterpreting E=mc^2. c^2 is a constant of proportionality that arises from the mathematical axiom that the speed of light is constant for all observers.

     

    All it says is that if you turned a given mass m into energy, you'd have m * 299792458^2 joules.

     

    (The more accurate version is E^2 = m^2c^4 + p^2c^2, which also leads to a fundamental property of matter which is E-P invariance (rest mass is constant, therefore E^2 - p^2c^2 = constant).)

     

    what would lead you to assume that FTL travel is unlikely?

     

    E=mc^2 has little to do with FTL, or just plain lightspeed travel, being impossible.

     

    It's the gamma factor, 1/SQRT(1-v^2/c^2).

     

    For example, the relativistic definition of momentum is gamma mv. As v -> c, gamma -> infinity, therefore a massive object moving at the speed of light would have infinite momentum, and would therefore require an infinite impulse to reach said speed.

     

    Beyond the speed of light, the gamma factor becomes imaginary, but that's another issue entirely.

  5. Nowhere in your post do you really respond to the meat of my argument.

     

    I don't, really. I like to attack arguments in, occasionally stupid, different ways to see if they hold up, or rather, to see how the person proposing this thing I don't know much about holds up.

     

    It's been a reasonably successful method of learning about new things; if someone can't hold their position and give evidence in the face of an attack, then it's not really worth learning about.

     

    Obviously this works better in an academic environment, when people are more likely to know a fair bit about their subject area, but you seem a fairly intelligent chap.

  6. for what values of x can you get negative numbers from (x^2)^½ ?

     

    Any. Squaring something is a many to one function, square rooting something is a one to many function. The square root of 5 squared is ±5; one's not just the inverse of the other.

     

    also make sure you balance two sides of your equations

    SQRT(5) = 2.24 (2 DP)

     

    I used SQRT(5^2) at first, and I lost the ^2 at some point. I did, however, edit it to SQRT(25) some 10 minutes before you posted.

  7. i said absolute value because (x^2)^.5 only give positive values.

     

    What?

     

    |(x^2)^½| gives only positive values, (x^2)^½ = ±x.

     

    it does equal ±x, but |x| is more accurate.

     

    Again, what?

     

    Ignoring that I have no idea what you're talking about, ±x gives more information than |x| and so would be more "accurate" by any useful definition of accurate.

     

    For example,

     

    SQRT(25) = ±5.

     

    This has described both possible outcomes.

     

    SQRT(25) = |5| is wrong, as |5| = 5 and SQRT(25) = -5 (in one of the two cases)

     

    |SQRT(25)| = 5, but it is impossible to tell whether that 5, without the modulus, would be +5, -5 or ±5.

     

    Now, if this is you trying to mock reductionism for including less information and being wrong, fine. Go back and make it clearer. If not, then see above.

  8. Don't buy this kind of reductionism.

     

    It's only reductionism in the sense that there are only four forces which have any evidence for them. DAMN THAT EVIDENCE.

     

    If you take those four fundamental forces and all the fundamental particles, you can't predict the properties of just about anything, and certainly not the properties of materials you need.

     

    Well, you can't predict (for example) the form my table takes if you try to work up from the atomic level, but that's more due to our limit of being able to solve the wave equation. Our limit to work with the incredible number of fixed and random variables that exist in this kind of thing.

     

    Of course, you can't do without[/i'] them either, but my point is that merely boiling everything down to its constituents (reductionism) is ineffective.

     

    Ineffective in what sense?

     

    This may be because it is wrong, and there exist emergent phenomena that must be taken into account.

     

    Then create experiments to document them. Just saying "science sucks and is wrong" isn't productive in the slightest.

     

    Or it may just be that it is just not useful.

     

    The model of forces we have seems perfectly useful, from the point of view of, say, modelling how an atom or molecule works, or how they interact, or indeed anything we can in fact measure. If it didn't have some predictive power and didn't agree with observation we wouldn't be using it.

     

    Either way, keep in mind that our world is full of vast numbers of interesting phenomena, and that filing them away into a few categories is scientifically untenable.

     

    Untenable, eh?

     

    "Describing the observeable universe as a finite number of possible types of interactions between a finite number of possible types of particles has not been shown to be inconsistent with empirical evidence and has been useful in predicting various things."

     

    Seems perfectly tenable to me.

  9. if mass is energy and energy is conserved, mass must therefore be conserved too.

     

    Energy isn't conserved unless you take mass into account. Mass isn't conserved unless you take energy into account.

     

    Mass is not conserved in and of itself.

     

    Lets say you have one particle, mass m, moving at another particle of mass m, at 3/5 c. Lets say they form one particle of mass M when they collide. This will, if you go through the maths, be moving at 1/3 c. M will be greater than 2m.

     

    Mass is not conserved.

     

    wikipedia has a lot on this topic:

    http://en.wikipedia.org/wiki/Mass-energy_equivalence

     

    Wikipedia has forgotten the gamma factor. Or rather' date=' you've only chosen to read the bits of the article talking about rest mass, and ignored the links to the section on mass dilation.

     

    light is mentioned among the energies which can be said to have mass

    so when measuring the mass of a photon, what you're really doing is measuring the energy contained in the photon and measuruing the energy as though it were converted to mass.

     

    What? No. That's not how you measure the mass of anything.

     

    supposing you have a kilo of matter in a closed system, convert it to energy, you now have 1 kilo of energy because the system cannot lose energy and mass is energy.

     

    You have the equivilent of a kilogram were it made into energy, but you do not have a kilogram of anything actually in the closed system. It doesn't actually have that mass.

     

    a photon does not go with inertial dialition, that's why they dont have infinite momentum, but since they have momentum, they must also have mass which is related only with their speed and frequency, their rest mass is 0 because slowing it down to 0 speed is, in essence, doppler shifting it untill it has 0 energy. when you slow a photon, the mass in the form of energy transfers to whatever slowed it down so the object that slowed it down now has the photons mass in the form of heat because of the equivalence between mass and energy.

     

    Inertial mass, and you can't actually slow a photon down per se. They're always travelling at the speed of light on an atomic scale, they just hit things along the way. It's like the difference between my average velocity when walking into town and my average speed.

  10. If we underwent to genetic alterations' date=' we could change into a different species.

     

    If a genetic caste system gets put in place(which would never happen while the U.S or Europe had a significant amount of power, but the U.S and Europe are declining due to militaristic arrogance, reckless spending, overextension, socialist policies, ludditism, Peak Oil, and globalization) then it may not be very long before we have two different species.

     

    If there is one group of people who are engineered to be perfect, and ontop of that have non-human or artificial genes that give them significant advantages, then it may not take long at all to create a new species.

     

    The downside of course is, if your not part of the new geneticly modified class, then that could be a problem. Most likely(unfortunately) it's going to be dictators/politicians, and the super rich, whose offspring will be blest with this technology.[/quote']

     

    Alas, no.

  11. how can u treat an animal with no respect like that

     

    Animals don't respect me. I give those guinea pigs food and water all the time, and when I ask them, nicely, to be quiet while Doctor Who is on, what do they do?

     

    Bloody freeloaders.

  12. Compaq is rated 11th by PC World Magazine in terms of quality and satisfaction. Alienware, eMachines and Acer are the top three

     

    Which just goes to show that money doesn't buy sense. Alienware machines tend to be poorly made, and are extremely overpriced.

  13. I think i might want something a little more powerful. what would you guys recomend. im trying to keep it under $200 preferably under $100.

     

    You're not going to get something particularly powerful for under $100 - that, for the price, is a good video card that will certainly run most new games, although for how long this is the case is debateable.

     

    In the mid $100-$200 range, http://www.newegg.com/Product/Product.asp?Item=N82E16814102688 is a good card that can run anything pretty well. You're not going to get a world beater without spending a hell of a lot more money than is really worthwhile, however.

     

    What other sort of components are you looking at?

  14. i was under the impression that speed was relative to a medium (space)

     

    No, SR states that all velocities are relative to observers, each of which are equally valid, and there is no medium to be relative against (no aether).

     

    and that relative velocities can be up to 2c but the relative momentum is always <C. in newtonian physics momentum p = mv

    is relativity' date=' p = gamma (mv)

    so when the two momentums are added together and converted back, some how the momentum tells us that 0.5c + 0.5c = 0.8c

    this has been discussed better else where.[/quote']

     

    If you have two things going towards eachother, at speeds a and b, the speed at which they approach eachother (in a reference frame moving along with one of them) is given by (a+b)/(1+(ab/c^2)). "Momentum is always <C" is meaningless, I'm afraid.

     

    Interactions can take place faster than c, for example if you had two stiff rods in an X shape, moving <- and ->. If they had a recession speed of c, the place where they cross would move faster than c.

  15. The best way to make a computer, if you don't know anything about the individual components, is to give an idea of what you want it for and a preferred/upper price limit, and have someone who does know about it do it for you. The potential for pitfalls if you're not sure of what you're looking at is enormous.

     

    Oh, and if it's not essential immediately, wait a month and a half for the Conroe to come out.

  16. I'd recommend a Riva TNT2. Actually, I'd recommend starting again from scratch as you could get something at least three times as powerful for under £300.

     

    without changing to a DVI monitor

     

    You don't actually have to use a DVI-monitor with DVI-out. There are adapters.

  17. Beside, it is known that C60 is a very hard material, and it is in sphere shape, I would like to know is there any bond between C60 molecules so that C60 could be observable to our naked eyes (I have not ever seen C60).

     

    Van Der Vaals forces, like, well, anything that isn't giant covalent, ionic or hydrogen bonded. However, it is unlikely that there exists enough buckminsterfullerene in the world for it to be visible to the naked eye.

  18. True, but science fiction has a habit of eventually becoming science fact, whereas fantasy has no chance of becoming reality

     

    It really doesn't. There are some examples of things from science fiction books that now exist, that didn't at the time, (ignoring hard sci-fi, which is based on existing science) but to say that it makes a habit of it ignores that the cases in which this happens are the vast exception.

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