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  1. #2476
    MadMojoMonkey's Avatar
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    Quote Originally Posted by OngBonga View Post
    Our motion through spacetime is always c. Our motion through space is not. So if we set c to 1, our motion through time is the reciprocal of our motion through space. If we move slower than c in space, we move faster than c in time, such that the product of the two is equal to 1 (c). I think this complicates matters.

    Basically we move forwards in space and backwards in time. That is my Sunday morning hypothesis.
    But moving faster than c is moving backwards in time (at least in some inertial frames).
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  2. #2477
    MadMojoMonkey's Avatar
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    If you were coming toward me, and accelerated through c...
    Until you reached c, I'd see you approaching from a long, long way off.

    Then the moment you matched c, I'd suddenly see you teleport to being right in front of me, and there'd now be 3 of you.
    The current you immediately bifurcates into a you and a past you. The past you zips away along the path you came, moving backward in time... absorbing fuel into its rocket engines to accelerate in the direction of the exhaust (inhaust?). This continues as your distant ship is approaching in forward time. Eventually the 2 past yous will meet at some intermediate point and disappear, leaving only the current you in my timeline.

    Fun
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  3. #2478
    MadMojoMonkey's Avatar
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    Just for kicks, I calculated the Planck length-second.

    With h
    ~4.051(10)^-35 m s

    With h_bar:
    ~1.616(10)^-35 m s

    where m s is meters*seconds, not milliseconds.
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  4. #2479
    Quote Originally Posted by MadMojoMonkey View Post
    With h_bar:
    ~1.616(10)^-35 m s
    This is really really interesting. See how long it takes to figure out why.
    Quote Originally Posted by wufwugy View Post
    ongies gonna ong
  5. #2480
    I'm legit curious if your calculations are accurate here or if you've just made some kind of mistake.

    I have no idea what the implications of that are if accurate, let's just say my mind would be utterly blown unless you can give a geometric explanation for it.

    Let me know when the penny drops.
    Quote Originally Posted by wufwugy View Post
    ongies gonna ong
  6. #2481
    MadMojoMonkey's Avatar
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    I can explain how I used the Buckingham Pi method to calculate it. I can't explain what it means, 'cause I never introduced any physics into my calculation.

    Here's how it goes. It's a lot of very simple algebra, so don't be daunted by a wall of math.

    We have 3 units we consider fundamental: [c] = m/s, [G] = m^3/(kg s^2), and [h_bar] = kg m^2/s.
    I'm using square brackets to indicate the units only, w/o the magnitude.

    We want something with units m s.

    We'll find it by raising each of our fundamental units to some unknown exponent, then solve for those exponents.

    [c]^x + [G]^y + [h_bar]^z = [m s]

    From here on, it's going to help a bit to write out exponents in a certain way.
    For m, I'll write m^1, and for 1/s, I'll write s^-1.
    This will be clear in a bit.

    [m^1 s^-1]^x + [m^3 kg^-1 s^-2]^y + [kg^1 m^2 s^-1]^z = [m^1 s^1]

    That's ugly. But since it's all exponents, we actually get 3 equations in 1, and that is exactly what we need to solve for those 3 unknowns.

    The m equation:
    1*x + 3*y + 2*z = 1

    The s equation
    (-1)*x + (-2)*y + (-1)*z = 1

    The kg equation
    0*x + (-1)*y + 1*z = 0

    From the last equation, we solve that y = z. Plug that into the other 2 equations and simplify.
    x + 3y + 2y = 1
    x + 5y = 1

    -x - 2y - y = 1
    -x - 3y = 1

    Let's add the 2 equations to eliminate x
    x + 5y = 1
    -x - 3y = 1

    0 + 2y = 2
    y = 1

    plug that into one of the above equations
    x + 5 = 1
    x = -4

    And we're done
    x = -4, y = 1, and z = 1


    Also... I did find a mistake in my prior work, so this is not the result I posted earlier.
    Never hurts to go over your own work.


    Wrap it up:
    [our new constant with units m s] = c^-4 * G * h_bar
    = G h_bar / c^4

    which, according to google is
    8.714(10)^-79 m s

    And it did tell me the units on my result, and they are my target units, so I'm prob. good this time.
    Just type "G*hbar/c^4" into Google to see for yourself.
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  7. #2482
    MadMojoMonkey's Avatar
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    Quote Originally Posted by OngBonga View Post
    I'm legit curious if your calculations are accurate here or if you've just made some kind of mistake.
    I did make a mistake in my initial calculation.

    When I added the 2 equations, I accidentally said 1 + 1 = 0, which left we with the incorrect answer y = z = 1/2 instead of 1.

    So the result I posted earlier was the SQRT of the better answer.
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  8. #2483
    With h_bar:
    ~1.616(10)^-35 m s
    What you don't seem to have realised yet is that here, your solution for h-bar is h.
    Quote Originally Posted by wufwugy View Post
    ongies gonna ong
  9. #2484
    MadMojoMonkey's Avatar
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    Quote Originally Posted by OngBonga View Post
    What you don't seem to have realised yet is that here, your solution for h-bar is h.
    It's not remotely the same.

    h = 6.626(10)^-34 J s
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  10. #2485
    Ok let me rephrase.

    Your solution for h-bar is the Planck length
    Quote Originally Posted by wufwugy View Post
    ongies gonna ong
  11. #2486
    MadMojoMonkey's Avatar
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    Quote Originally Posted by OngBonga View Post
    Ok let me rephrase.

    Your solution for h-bar is the Planck length
    The magnitude was the same, but the units were off.

    Which means I made yet another error somewhere in my calculation.

    L_Planck = SQRT(hbar G / c^3)

    What I was trying to calculate was SQRT(hbar G) / c^2
    which wouldn't have the same magnitude because of the exponent on c in the denominator.

    I got the exponents wrong by a factor of 2. My revised answer is
    G * hbar / c^4
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  12. #2487
    Ok so I think I know why h-bar and not h

    It's the uncertainty principle. It's the limit at which we can have certainty of the location of a particle. To locate it any further would give rise to potentially infinite momentum. h-bar seems to be the point at which this infinity is reached.
    Quote Originally Posted by wufwugy View Post
    ongies gonna ong
  13. #2488
    MadMojoMonkey's Avatar
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    My point is that whichever you choose to use in the Buckingham Pi method is irrelevant.
    The "unknown constant" that Buckingham Pi cannot solve for just absorbs or corrects for the divisor of 2pi.

    If you can show me a derivation of the Planck Length that is based on physics, and not math, then maybe I'd have some hope of interpreting the meaning of that value. But w/o any physics attached to the derivation, any physical interpretation is speculative.

    The notion that the Planck Length represents a lower limit in space beyond which our current models make no predictions seems sound, but I haven't actually seen a proof that it is so. Certainly nothing which resolves the h vs. hbar vs. some other unitless scalar multiplying the result in question. It's just sensible to note that our model has limits, and if that is one of them, then I can accept that.
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  14. #2489
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    Quote Originally Posted by OngBonga View Post
    Ok so I think I know why h-bar and not h

    It's the uncertainty principle. It's the limit at which we can have certainty of the location of a particle. To locate it any further would give rise to potentially infinite momentum. h-bar seems to be the point at which this infinity is reached.
    There's nothing wrong with reducing the uncertainty in either 1 of the terms on the LHS of the inequality, provided the uncertainty in the other value is of no concern to you.
    This principle is what allows the LIGO to work. They're measuring length changes many orders of magnitude less than the diameter of a proton. Which can only be done if you don't care at all about the uncertainty in the momentum being arbitrarily large.

    The universe tends to put a kibash on infinities. Conservation Laws are very effective at preventing any system or object from gaining infinite energy or momentum or a few other properties. The requirement to inject infinite X to the particle or system requires something else lost infinite X (provided X is conserved). The lack of an infinite to lose prevents the rise of anything else to infinite.
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  15. #2490
    MadMojoMonkey's Avatar
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    I learned some new stuff about climate change today that I think is interesting.


    If we released *all* the carbon trapped in *all* the fossil fuels and put it into the air, well... That's technically where the Carbon came from in the first place. I.e. this isn't "new," geologically speaking.

    The rise and fall of average temperatures on Earth is a well-catalogued "cycle". Cycle in quotes 'cause it's pretty random looking, but does go up and down quite a lot. Global temperatures have been much warmer than our projections in the past - while there was life on Earth doing dinosaur things and other things.

    The troubling thing about the current trend of warming isn't that global temperatures haven't been that warm before (even in the worst case projections). It's that in the past, the temperature changes happened over centuries or millennia, not over decades. The rapid pace of change puts pressure on every economy, not just human economies, but ecological economies.


    Sea levels could rise up to 230 ft if all the ice trapped in glaciers melts. Different coast lines wont matter all that much. The rapid changes don't allow biological evolution the time to catch up, though. This will lead to a large reduction in biodiversity.

    The effects on the food chains will be unpredictable, but humans have pretty well secured our food chains by now. We may have to adapt what we grow where, but we do have all that figured out well enough to sustain huge populations, even on a warmer planet.
    You can find any pattern you want to any level of precision you want, if you're prepared to ignore enough data.
  16. #2491
    I hope that got deleted before anyone digested it.
    Quote Originally Posted by wufwugy View Post
    ongies gonna ong
  17. #2492
    I was blabbering how the math didn't check out, that we were three orders of magnitude short of ice.

    My mistake was to not convert km to m when considering height of water, which accounts for the three orders of magnitude.
    Quote Originally Posted by wufwugy View Post
    ongies gonna ong

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