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Can someone explain?

  1. Jun 12, 2003 #1
    In this weeks new scientist there was an advert for the following site- www.thefinaltheory.com

    Is what they are saying true because it sounds a bit suspicious to me?

    For example it states that;

    And I know the answer to this and it is not 'impossible according to today's science'.
     
    Last edited by a moderator: Jun 12, 2003
  2. jcsd
  3. Jun 12, 2003 #2

    LURCH

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    I couldn't get the link to work, but based on the example you've provided I'd say you've been very generous in your description (vis: "a bit suspicious"). Anyone who makes the unqualified statement that "...science has no explanation for this...occurance" in regard to the speed of light propogation through verying mediums is less scientifically literate than the average layman, or flat-out lying. Sounds to me as though the makers of this site have an agenda, could you discern what it might be?
     
  4. Jun 12, 2003 #3

    enigma

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    The link is not working for me.

    IIRC, these folks sent out emails a few months back advertising a "Brand Spankin' New Scientific Theory"TM, and it will only cost you $39.99 to find out what it is.

    Yeh. I realized that tallying up their crackpot index wouldn't even be worth the effort. It's easily over 300.
     
    Last edited: Jun 12, 2003
  5. Jun 12, 2003 #4

    Janus

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    Great, yet another electrical engineer out to rewrite physics. Off to TD it goes.
     
  6. Jun 12, 2003 #5
  7. Jun 13, 2003 #6
    After viewing the beginning and first 25 pages, I think McCutcheon's book is worth considerably less than the asking price of $30 minus a nickel. Wait a while and you can probably get it for pennies.
    it has a nice cover photo.
     
  8. Jun 13, 2003 #7
    So did the link work for any of you because I tested it and it worked fine for me.
     
  9. Jun 14, 2003 #8
    So what are the simple explainations for these?
     
  10. Jun 14, 2003 #9

    Janus

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    As to how light "speeds back up" after leaving a substance, here is the easiest way of looking at it.

    Photons always travel at c. When they enter a transparent substance, however, they encounter molecules/atoms. As they do so, the molecules absorb the photons. When that happens the photons cease to exist.

    Then after a short delay, the molecule , re-emits a photon traveling in nearly the same direction as the first. This new photon, upon creation, begins to travel at c until it encounters another molecule.

    These slight delays between absorption and emission, increases the time it take from the time a photon enters a substance to the time one emerges form the other side.

    This give the impression that light slowed down while traveling through the subtance.
    (If you knew that some friends had left their home, which was 60 miles distant from you, at a given time, and they arived at your house 1 1/2 hrs later, It would seem to you that they drove the distancea 40 mph. Even if, while on the road, they drove at 60 mph, but stopped for gas along the way, got a quick bite to eat somewhere, had to fix a flat , etc. )

    Light travels though a substance in similar fits and starts.


    As to why a substance heats while light travels through it, that is simply because there is no such thing as a perfectly transparent material. Not all the photons are re-emitted after being absorbed.
    And that's just for the frequencies that the substance is normally transparent to, there are many frequencies for which the substance isn't transparent.

    These absorbed photons are what contribute to the heating of the substance.
     
  11. Jun 14, 2003 #10
    Janus,

    Somewhere an explanation is needed why the re-emitted photons continue along wave fronts just as Young and Fresnel said waves should go, and don't just scatter in all directions. It even works in gases and liquids, not just in crystallized translucent solids.
     
  12. Jun 14, 2003 #11

    Hurkyl

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    Conservation of momentum.


    Consider first an atom in the interior of an object. Far more likely than not, this atom is in some sort of stable equilibrium state with respect to other nearby atoms.

    When this atom absorbs the photon, it absorbs the momentum contained in that photon, which changes its state of motion. The atom is no longer in equilibrium! The most likely eventuality is that the other nearby atoms will push it back into equilibrium causing it to emit another photon. Since the net effect is that the atom we were observing has returned to its equilibrium state, it retained none of the momentum of the original photon, and thus the emitted photon must have exactly the same momentum as the original photon (i.e. it travels in the original direction).

    For atoms near the surface of an object, it isn't surrounded by other atoms so it doesn't experience quite the same restoring force, which causes the re-emitted photon to either be a reflection of the original, or bent from the original.
     
  13. Jun 14, 2003 #12
    Thanks Janus but as I said in my first post I knew the answer to that one. It's the others that I don't have a rational explaination for.
     
  14. Jun 14, 2003 #13

    Hurkyl

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    Gravitational perpetual motion

    A key statement in his argument is:

    It should be no surprise that he concludes perpetual motion because he neglects the very thing that would prevent perpetual motion! The reason perpetual motion is "impossible" is precisely because of irreversible effects like friction or wind resistence.


    The work function

    He has a very narrow idea of what pushing is. He is imagining we walk up to a boulder, put our hands and/or shoulder against it, and tense our muscles in a way that would apply a force to the boulder and the ground. Those actions do require energy... however none of that energy does any work whatsoever on the boulder; it only does work in our bodies.

    Still not convinced? Imagine if you simply leaned up against the boulder. Again you're pushing it, but it requires you to spend no more energy than leaning against a wall, and probably requires you to expend less energy than simply standing up.


    The most clever and concise explanation I've heard of this is:

    "Of course the moon is falling towards the earth; it's just moving fast enough so that it misses the earth every time!"

    The main question is why he would think energy would be required. If the moon is moving in a perfectly circular orbit, it's speed remains constant (so that its kinetic energy remains unchanged) and it is maintaining a constant height (so its gravitational potential energy remains unchanged), so the energy of the moon is unchanging. There is no change of energy, so why would he think there should be work done?


    Fridge magnet

    Again, the energy of the system is remaining unchanged, so there is no work being done. (This will be a common theme to answer most of his questions)

    The more interesting question to ask is why magnetism and glue should be expected to behave any differently. Or more interestingly, why doesn't the refrigerator simply collapse under its own weight? After all, it must take energy to keep the top of the fridge up there, right?

    The physical principle is easy; the force of gravity acting on the magnet is less than the maximum static frictional force possible between the fridge and the magnet.

    The magnetic force essentially creates a tiny indentation in the refrigerator in which the magnet holds itself. In order for gravity to drag the magnet down, it would have to further deform the surface of the refrigerator to create a path through which the magnet travels. However, if the magnet is strong enough, the indentation will be deep enough so that gravity cannot deform the surface sufficiently.


    Freezing water

    The molecular bonds between H2O molecules in ice are peculiar; they like to arrange them in hexagons. This is pecular because hexagons have a lot of empty space between them, so this isn't a particularly efficient space-packing scheme.

    When H2O is in liquid form, the molecules are moving around fast enough that they can't settle into the hexagonal pattern. However, at around four degrees celsius, the intermolecular forces between H2O molecules begin to get strong enough to start arranging themselves into hexagons despite the random motion fo the molecules, and as water cools from four degrees celsius to zero degrees celsius, the water will expand as its molecules arrange themselves into these hexagonal shapes.


    It is precisely because water molecules have energy that they shuffle around resisting their urge to arrange themselves into hexagons. If you drain the energy out of the molecules, they start arranging themselves into that space-inefficient hexagonal packing and thus the water wants to expand in volume.

    Water, incidentally, is a highly incompressible substance, which is why hydraulic systems work. Thus, when the water wants to expand, it is extraordinarily difficult to stop it; in other words, brittle metal piping doesn't stand a snowball's chance in hades; the only way piping could survive is to expand with the water.


    Heavy objects on a tabletop

    Again, there is no reason to suppose the energy levels are changing.


    However, it does require energy to break molecular bonds. Since there's no energy being input into the system, the bonds don't get broken.


    Einstein's Special Relativity Theory is all a mistake

    Seeing how I can't find any reason why his example should be considered a mistake, any appearance in the SR derivation of his example, nor does he point his finger directly at any flaw in the derivation, there isn't really anything to which I can respond in this section.



    Mistakes, logical errors, and coincidence explain experimental evidence.

    That title should speak for itself.


    The twin paradox

    Spoken like someone oblivious to the fact that the formulae of SR hold only in inertial reference frames! The asymmetry is clear; one twin has to accelerate and the other does not. The time dilation equations work in one frame (the earthbound frame), and not in the other (the spacebound frame).

    If you analyzed the picture in any inertial reference frame, it is clear that the earthbound twin would be older than the spacebound twin when they meet again. This paradox only occurs when you insist on fallaciously applying special relativistic formulae in a non-inertial frame (that of the spacebound twin).


    light speed limit

    His "explanation" brings up more questions than the question he's trying to answer. Why should a method of acceleration have a limit as to what maximum speed they can impart?


    Flying atomic clocks

    His argument is based on the same flaw as that of the twin paradox.


    Other evidence for Special Relativity

    It would be amusing to see his explanations, but I'm certainly not gonna pay $30 to do so. :wink:


    Gak, Im over the post length limit; I didn't know there was one!
     
  15. Jun 14, 2003 #14

    Hurkyl

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    Big bang

    Yes; that space is expanding. And the further a galaxy is from us, the more space between us and it to expand, thus if we interpret the expansion as causing distant galaxies to move away, then a further galaxy would be receeding faster.


    Except General Relativity... (Not sure if LQG or ST predict it yet, though I'd presume LQG does so by default since it's based on GR)


    Except that the Doppler Effect is a trivial consequence of any event occuring with a regular frequency be it sound waves, light waves, or even an eccentric man rolling a bowling ball at you every second.


    But the whole point is moot because it is known that the redshifting is not due to the doppler effect, but is believed to be caused by the expansion of space. (Which, again, would shift frequencies downward for any frequency based event)
    E=mc^2

    I think that's the first thing he's said that was correct.

    This one would actually take some equations to prove, so I'll skip covering it to keep in spirit with the (comparatively) simple explanations I've been giving thus far.


    Protons in the atomic nucleus

    He gives the answer himself; the strong nuclear force, the triumph of Quantum Chromodynamics, and he gives no plausible reason to disbeleive in it. :smile:
     
  16. Jun 14, 2003 #15
    The key to most of this is the universalisation of a muscle version of work and a concomitant necessity for expenditures of energy, which is supposed to just disappear like fuel from a tank.

    McCutcheon is just repeating the same kinds of complaints that were issued time and time again against relativity theory and quantum theory during the twentieth century.

    Nice job, Hurkyl!
     
  17. Jun 15, 2003 #16
    As quartodeciman said-
    Thanks.
     
  18. Jul 4, 2003 #17
    Jack...Think of it as a car driving on a long flat road with the accelerator in a specific position. If a large wind starts blowing in the opposite direction the car is moving, it will slow down. When the wind stops the car will speed up without using more energy.
     
    Last edited: Jul 5, 2003
  19. Jul 23, 2003 #18
    Actually grounded, that would be an incorrect analogy. Your analogy implies that the photo is being driven by some sort of force. I think Hurkyl's atom-jumping conservation-obeying photon-matter-interaction is a much better picture of what's actually going on. The photons themselves never actually slow down at all, they simply experience multiple rest stops along the way.

    At first I was going to question the momentum conversation since this would seem to violate quantum mechanics (and it most certainly would) if it wasn't for the surrounding environment of the other atoms in the material. The effect of the neighboring atoms is to change the probability densities of where a photo is most likely to be emitted. I should have thought of that myself, but I must confess to be a bit slow at times. I think it has something to do with the neurons in my brain taking too many rest-stops during their meanderings. Stuff like that happens when a person approaches the age of the universe. But that's a whole other theory.
     
  20. Jul 31, 2003 #19
    Re-A: This is impossible according to today's science. No object in nature can speed up of its own accord after being slowed down

    The speed of a photon is dependant on the density of the field it is passing through. Therefore a photon exiting a lens is moving from a dense field into a less dense field and will acelerate, only the force of momentum is constant. Photons, like all massless bosons are not subject to drag or friction.
    A photon approaching a Black Hole slows down it does not take 'rest stops'
     
    Last edited by a moderator: Jul 31, 2003
  21. Jul 31, 2003 #20

    Hurkyl

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    Recall that in general relativity, measurements are only required to be locally like special relativity.

    In particular this means that an observer next to the photon will necessarily see it moving at c, even if the photon is near a black hole.
     
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