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Posts posted by losfomot

  1. I hope I am not sounding arrogant or trying your patience Aeschylus. I do not mean to, and I most definitely appreciate your replies, as well as respect the input you give, as it obviously comes from a mind more schooled than my own. I am only trying to understand what it is that you're trying to say. :)


    I have a hard time accepting an answer that says my question is meaningless. What does that mean? There is no answer? The answer is unattainable via our current understanding of the universe? The answer is unattainable. period.?

  2. The question becomes menaingless in SR, as you cannot define reference frame for the photon so you cannot talk about whetehr or not time passes for a photon. The problem is that peole use theb formula for time dialation and input the value 'c' and think the answer is meaningful as it tells you nothing about the photon's reference frame.



    When you say 'it tells you nothing about the photon's reference frame.' it sounds, to me, like you are simply saying that we don't have enough information to answer the question at hand, or... special relativity cannot tell us whether or not time passes for a photon.


    There IS an answer to the question... it is a very simple question. We just don't know the answer, and the answer cannot be found using SR. (This is what I assume you mean but do not say)


    This is very different from the question being 'meaningless'. Of course, you always word it like so: "The question becomes meaningless in SR..."


    you cannot define reference frame for the photon so you cannot talk about whetehr or not time passes for a photon.


    Sure I can!... Isn't that what we're doing? :D

  3. The effects of special relativty do apply as indeed they apply to everything (the Lorentz invaraince is beleived to be a fundmanatal property of nature within it's limits).


    BUT in special relativty a frame of reference cannot be defined for a photon.


    Therefore it is meaningless in special relativity to talk about the 'photon's perspective'.


    I can only interpret this as meaning that time does not exist for the photon. This would satisfy all three of the above quotes, as well as answer my question.


    If the photon experiences zero time, it obviously adheres to the effects of SR.

    If the photon experiences zero time, a frame of reference cannot be defined.

    If the photon experiences zero time, it would have no time to have a 'perspective'. Therefore, I suppose, you could say that particular phrasing of the question would 'technically' be meaningless.


    Am I correct? and if not, would it help to rephrase the question like so:


    Does time pass for a photon?

  4. Everything I've found so far in my Internet search for the question "What does the universe look like from the perspective of a photon?" has led to the following answer:


    A photon experiences zero time and zero distance. Essentially, it exists for only an instant (from it's own perspective), no matter how far it travels (from an outside perspective). This seems to exactly coincide with what Special Relativity says about an object moving at such relativistic speeds.


    However, it has recently come to my attention in another thread (another thread ) that because a photon has no mass, the effects of Special Relativity do not apply:

    Mass and Energy can be viewed as equivilant not equal. That and one cannot selectively apply lorentz transforms (ie time and not space or vice versa). The theory of SR applies only to inertial[/i'] reference frames, as in those that contain mass.


    So it seems that it is not true to say that a photon experiences zero time... which brings me to my question:


    What does the universe look like from the perspective of a photon?


    (with respect to time, distance, etc.)

  5. Without time you cannot have movement as movement is change in spartial coordinates with respect to time. The postulates of special relativity apply only to inertial reference frames, which as I have said before does not apply to photons as they have no mass.


    I don't undertand how this could be so. Mass = Energy, I thought. Athough photons have no mass they do have/are energy. And sub-atomic particles are observed via the effects of SR everyday in particle accelerators. Are you saying that SR effects are observable on particles no matter how close they are to having zero mass, but once that zero is reached BAM! they follow a whole new set of rules? If this is known to be true, then so must the 'new set of rules' be known. What are they? How much time does a photon experience on a journey of, say, one hundred light years if not zero? One hundred years?


    Now physicists added electron detectors in each slit to determine which slit each electron travelled through. They ran the experiment again and recorded the results. Suprisingly' date=' this time there was no interference pattern, only two stripes left on the photosheet!! Physicists thought perhaps the electron detectors altered the experiment or motion of the electrons. So they ran various combinations of the experiment to determine the problem....


    source: "The Elegant Universe" by Brian Greene.


    Am I the only one who finds this extremely wierd?[/quote']


    I, unfortunately, also do not have this book, but all my searches for quantum erasure via the double slit experiment obtain results from experiments using photon 'entanglement.' Even the link you gave as an example deals with 'entanglement.' But your description of the experiment in this book by Brian Greene SEEMS to imply quantum erasure via some other form of 'electron detectors'. Am I right, or does Brian Greene also describe an experiment that utilizes 'entanglement'?


    I am curious if this quantum erasure has been observed without this specific method of detecting which electron went through which slit.


    By the way, I think every High School student should be exposed to a live demonstration of this effect. It is EXACTLY the kind of thing that would jostle an interest in science.

  6. alright, what if I were to create a mirage by superheating the air around an object...then i were to focus a high powered laser, such as the ones attached to 747s that are used to take down missiles, what would the affect be? Would the beam refract off of the mirage? would the object underneath be untouched? Or would the laser only be refracted for several degrees, then continue on through the mirage?



    First off, mirages (I believe) are a cumulative effect. By that I mean that you are looking down a stretch of highway or sand or whatever and you see what appears to be water or whatever (I like that word). This happens because of the air just above the road. But you are looking at the air above a stretch of road that is a hundred meters or more long. The accumulation of that air into a space about an inch or two wide from the perspective of your eye allows you to see the total refracting (or reflecting) power of all that air. What I mean is that if you were only looking over a meter of road, you wouldn't see that mirage (or at least not nearly as powerful). so I don't think you could apply the mirage effect to any anti missile defense plans you may have, as you would not have enough surface area to make a 'mirage' of any strength. I just looked over what I just wrote and it's confusing even to me and I don't even know if it is right.


    As for your experiment to see how laser light would react to a mirage... why don't you find a lonely stretch of flat highway on a hot day and set up a laser-pointer (or whatever) at whatever angle you like and follow the beam down the highway with a white sheet of cardboard to see what happens to it.

  7. I think YES. Simply because I just put forth a challenge that, if the moderators actions in the regular forums is any example, will be considered pseudoscience.


    Of course, if it is considered a 'pseudo-debate', and it is accepted, I would hope that any contributors to such a debate would take it a little more seriously than that alien one.


    So.... Yes.

  8. You can certainly change the wavelength of EM-radiation.

    Eg.Compton effect : Wavelength of X-ray changes in sub atomic interaction.

    I don't know of a method to do it for ultra violet light.


    I am curious, do they make use of this 'Compton Effect' in X-Ray and Gamma Ray telescopes?

  9. Thanks for all the input. I am aware of the redshift that occurs as a result of distant objects moving away from us at great velocities, but as Pulkit mentioned, that is pretty difficult to recreate in a lab which is what I'm looking for: a method of redshifting light artificially.


    Also there are crystals in which you can do nonlinear optics and get frequency doubling (the direction it's usually done) but you can also get difference frequencies, and go to lower values. So yes, it's possible.


    Thanks, I will try to find more info on this.

  10. Is it possible to redshift light?


    For example, can you take ultraviolet radiation and, using a lens or some other contraption, shift it into the visible spectrum? I don't mean interpret it as visible light, I mean physically change it into visible light.

  11. However, if you read the original article by Podkletnov and Modanese (the guys who created the gravity beam), it resembles a gravitational impulse, they don't know if it truly is or not, however.


    Of course not, in fact I have my doubts about a lot of what Podkletnov claims simply because, if he had something like what he says it would be the greatest discovery since sliced bread and the whole scientific community would be on it like flys to sh... er... like bees to pollen. I've read what he has claimed in articles as far back as 1992. I believe that 12 years is plenty of time for the 'discovery' to have come to light and it still hasn't aside for some unsupported claims. If this was all true (whether or not it is an actual "gravity" beam) then they sould have an independant team of scientists come in... witness the whole process... repeat the experiment... and confirm to the world that the effect is real. Since this hasn't happened yet, I am left in doubt of it all. Which is why I said MAYBE. :)

  12. Here's where your theory really breaks down for me. Life on earth has been around for almost as long as the planet has been around. The earth is like 4.6 billion years old and life is only a few hundred million years younger. The conditions necessary to support life on earth are very specific. We need a temperature that will neither boil nor freeze water. If gravity had changed over the 15 or so billion years since the universe was created and is constantly decreasing then the earth would not have held its constant and regular orbit around the sun and would not have sustained life. If gravity had changed that much then during that time conditions would have been similar to Mercury or Pluto and our Paleontological and Geological evidence clearly disputes this.


    That's where it breaks down for me as well. Of course I have heard of a lot of controversy about the accuracy of the dating methods used by historians (geologists and paleontologists). However, assuming them to be true, I have one last straw to grasp at... it lies in an error of my own in saying that my "theory" explains inflation. It seems the whole basis of 'inflationary theory' lies in the assumption that the 'inflation' happened in a very short time relative to the total age of the universe (while my little "theory" describes inflation as smoothly slowing down over the age of the universe). So if we let inflation be an entity seperate from the direct effects of gravity, then it could be proposed that 'inflation' fast forwarded us to a universe already very close to the one we see ourselves in. The change in the strength of gravity (and in the background radiation temp) could be proceeding so slowly now that stable orbits have been possible for the past 4 or 5 billion years.


    But even I agree that I am grasping at straws. Your argument is quite sound. I probably should have started a thread about whether or not gravity is a push, rather than try to explain the mechanics of the entire universe.


    I still think gravity is a push, and it is probably the source of our universe's 'accelerating expansion'. :)

  13. Photons do not have any mass and they feel the effect of gravity.


    I never said anything contrary to this did I?


    Also, if gravitation is energy like you state, what is the source of this energy?


    I don't know, but in my original post I suggested that it could be electromagnetic radiation (of a very high frequency) left over from the big bang.


    If we absorb this gravitational energy as you state, then why do we even bother with power plants? We could just use gravity.


    We already do. Where do you think HydroElectric power comes from?


    But as far as tapping into gravity as a DIRECT energy source... I think that may be a long way off... or maybe not ( gravity beam )

  14. This may be a little long but it makes so much sense to me, I just want someone else's thoughts on the matter. Thanks.


    So what do you think of the idea that Gravity is a form of energy, perhaps a high energy form of electromagnetic radiation (higher in frequency than the gamma rays we have been able to detect so far) This radiation (gravity) is felt as a PUSH, not a pull. We (and any other object near enough to a large mass) would feel it as a pull because mass absorbs some of this energy. so we are being pushed in all directions equally except FROM the direction of a nearby large mass. Therefore we would be pushed more toward the Earth (for example) than away.


    This would explain inflation (wouldn't it?) because gravity would have been pushing everything apart immensely more energetically soon after the big bang. This gravity energy is still pushing everything apart today, but with much less force (probably corresponding to the 4 degree Kelvin background radiation), and we see that this is so (our accelerating expansion).


    It would also explain the presence of so many heavier elements. A meager 15 billion years doesn't seem to be enough time for the production and distribution of these elements throughout the universe. But if Gravity were stronger in the early universe, then Stars would form more readily, with less mass needed to ignite them. Hotter burning stars that lived out there lives in much shorter time than they need today.


    It would explain the spiral arms we see in galaxies that appear as though they could only have rotated a few times ( or they would look like a jumbled mess with no arms discernible) Its because they HAVE only rotated a few times. Only recently has gravity weakened to a point where stable orbits are possible.


    It would explain why the galaxy ( and the universe ) is not teeming with intelligent lifesigns (like radio signals, and visiting species) Its because, although the universe is very old, the (gravitational) conditions that would support life have only recently been available in the universe.


    Phew... sorry about all that :rolleyes:

    Just an idea that seems to make more sense the more I think about it.



  15. Unfortunately I don't have a reference, (although I'm sure it would not be hard to find,) I recently read somewhere that temperatures on the moon during it's 'night' can reach minus (-) 150 degrees Celsius. This may seem extremely cold to some, but I don't understand this. If the moon has no atmosphere to keep heat in, then how does it maintain a temperature so high above absolute zero? Would a thermometer show a different temperature if it was hovering a foot off the surface compared to being in contact with the surface? And, if so, would that 'hovering' thermometer be colder?


  16. aman said in post # :

    If there is no mass out there other than the black hole then the warp of space-time becomes a moot point. I think.

    Am I close?

    Just aman




    If space-time is warped by a black hole then it is warped. It does not matter if there is other matter around to feel the effects (gravity) of that warp or not. You seem to be struggling with the old philosophical question "If a tree falls in the woods and there is nobody around to hear it, does it make a sound?"

  17. YT2095 said in post # :

    EM waves can indeed send a geiger counter "NUTS" as you say


    Yes EM waves can make a geiger counter go nuts, but gamma rays are included in the spectrum of EM waves. What about a MAGNETIC FIELD such as that generated (for a lack of a better word) by a permanent magnet. Surely this does not set off a geiger counter.

  18. OK.. It looks like nobody REALLY knows. But photons don't really make sense to me as the force particle... what energy of photon are we talking about? I would guess that they must be high energy photons because a small magnetic seems to have a powerful magnetic field... gamma radiation? Isn't that bad for us? Wouldn't a geiger counter go nuts around magnets? Its certainly not near the visible spectrum since we can't see it and we don't feel any heat. What about longer wavelengths? Microwaves would cook our hands everytime we touch a magnet. Radio wavelength photons? Somehow I don't think Radio waves could be concentrated enough to create the magnetic effects we see. Besides can't almost all wavelengths be blocked with something like lead? You can't BLOCK a magnetic field. YT mentioned something about a "DC" source of photons. I am not sure what this means but if it eliminates the 'wave' half of the wave/particle duality then we are still left with a 'particle' photon which still (i don't think) can't penetrate something like lead.


  19. Right... gravitons are the (supposed) force particles for gravity that we haven't detected yet. But what about a magnetic field. What is the force particle of a magnetic field? Have we been able to detect and confirm this force particle? Or is the magnetic force particle still as mysterious as the graviton?

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