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Pmb

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  1. Like
    Pmb got a reaction from Turtle in The What Was, Before The Big Bang   
    xyz - I know the other version, and it suggests walls of space by suggesting by suggesting a balloons surface which is simply not true.
     
    If that's what you think then you do not understand the analogy. A 2D occupant in the surface of balloon can walk all over the surface and never hit anything which could be thought of as a "wall." That's the whole point of that analogy.
     
    Every time you claim you know the analogy you say something which tells us that you really don't understand it like you did in that comment.
  2. Like
    Pmb got a reaction from Moontanman in The What Was, Before The Big Bang   
    xyz - Within the context of general relativity, space most certainly can expand and can be destroyed. Regarding the balloon analogy; most people misuse the analogy by thinking that its like a real balloon that, when expanded, occupies more space since they picture it as expanding into space. That's quite wrong and a misuse of the analogy. The analogy, correctly utilized, is that the surface of the balloon is what's expanding. But if you imagine that its expanding into something then you don't understand the analogy correctly. The analogy is one in two dimensions, not three dimensions. When you claim that the balloon is expanding into 3-space then all you're doing is misusing the analogy. The correct view of the analogy is to imagine that it's occupied only by two dimensional beings. As the surface of the balloon increases 2D beings, even thought they're at rest on the surface, move apart from each other. When they measure the amount of space that exists in their 2D world they find that as time goes on there is more and more of it. Define one point on the surface of the balloon as point N. Find the point which is the furthest away from it and call that point S. Now draw the straightest possible line possible that passes through N and you'll find that it passes through S. Place markers at equal intervals along that line. As time increases you'll find that there is more and more space between adjacent markers which means that the total length of the longest line is increasing.
     
    So while you might imagine space as being "nothing" it actually has properties which can be measured and they have been measured and what was found is consistent with general relativity. One way to make measurements is to measure the shortest distances between two points in space. The nature of the measurements will describe the space itself. The results of those measurements will depend on the surrounding  matter.
     
    So all your beliefs about space are wrong and have been proven to be wrong by observation.
  3. Like
    Pmb got a reaction from Moontanman in The What Was, Before The Big Bang   
    The truth of the matter is that nobody knows what was before the big bang. There's a theory called the Pre-Big Bang scenario which is based on string theory. Try looking it up using Google.
  4. Like
    Pmb got a reaction from sanctus in The What Was, Before The Big Bang   
    xyz - Within the context of general relativity, space most certainly can expand and can be destroyed. Regarding the balloon analogy; most people misuse the analogy by thinking that its like a real balloon that, when expanded, occupies more space since they picture it as expanding into space. That's quite wrong and a misuse of the analogy. The analogy, correctly utilized, is that the surface of the balloon is what's expanding. But if you imagine that its expanding into something then you don't understand the analogy correctly. The analogy is one in two dimensions, not three dimensions. When you claim that the balloon is expanding into 3-space then all you're doing is misusing the analogy. The correct view of the analogy is to imagine that it's occupied only by two dimensional beings. As the surface of the balloon increases 2D beings, even thought they're at rest on the surface, move apart from each other. When they measure the amount of space that exists in their 2D world they find that as time goes on there is more and more of it. Define one point on the surface of the balloon as point N. Find the point which is the furthest away from it and call that point S. Now draw the straightest possible line possible that passes through N and you'll find that it passes through S. Place markers at equal intervals along that line. As time increases you'll find that there is more and more space between adjacent markers which means that the total length of the longest line is increasing.
     
    So while you might imagine space as being "nothing" it actually has properties which can be measured and they have been measured and what was found is consistent with general relativity. One way to make measurements is to measure the shortest distances between two points in space. The nature of the measurements will describe the space itself. The results of those measurements will depend on the surrounding  matter.
     
    So all your beliefs about space are wrong and have been proven to be wrong by observation.
  5. Like
    Pmb got a reaction from sanctus in Relativity Wheel   
    re - the way that time dilates and length contracts are physically identical !
     
    Far from it. There were too many errors in your claims for me to want to bother correcting so I'll just correct this one to make a point, i.e. you don't know what you're talking about in relativity,
     
    In what follows let there be an inertial frame S and let S' be an inertial frame in standard configuration with S.
     
    Let the time interval between two events A and B which occur at the same location in S be dt (dt = proper time). Then it's value in S' will be dt' = dt/sqrt[1 - v^2/c^2]. I.e. dt' > dt  - Time dilation.
     
    Let there be a rod of proper length L be at rest in S. Then the rod's length in S' will be L' = L*sqrt[1 - v^2/c^2]. I.e. L' < L - Length contraction.
     
    This clearly demonstrates that you claim is wrong, as usual.
  6. Like
    Pmb got a reaction from sanctus in Relativity Wheel   
    A-wal claims that - ...special relativity shows that time is no different by treating coordinate time as simply another spatial dimension. In relativity there's no distinction and you don't need to specify which dimension is undergoing length contraction and which is undergoing time dilation because they're physically identical.
     
    Clearly wrong. E.g. time dilates whereas space contracts.  By merely looking at the metric one can see which coordinate is the temporal one and which are the spatial ones. And while particles travel in any direction in space they never travel backwards in time. By looking at the Lorentz transformation which relates coordinates between inertial frames its obvious that the temporal and spatial coordinates transform differently. No relativist/physicist worth his salt would make such a clearly wrong statement.
     
    pgrmdave - A-wal has all of this quite wrong. His grasp of relativity and physics in general is quite poor since he makes a lot of mistakes like this. Your response is quite correct. I've provide other opinions from Einstein and his colleagues on the subject of the difference between time and space in spacetime in what follows.
     
    As Einstein himself said, this is wrong. From Nature, Feb. 17, 1921, page 783
     
    Of course this point of view is universal for those who have a correct understanding of relativity, which A-wal does not. This means that all of Einstein's followers agree with what Einstein said here. For example; from Relativity; Thermodynamics and Cosmology by Richard C. Tolman, Dover Pub, page 29. In the section 14 entitled The three plus one dimensions of space-time
     
     
    From a much more modern text Introduction to Special Relativity by Wolfgang Rindler, page 51
     
     
    Note: It's important to note that one of the major differences between Euclidean space and spacetime is that they have very different metrics.
  7. Like
    Pmb got a reaction from CraigD in I Mathematically Proved That Einstein's Relativity Is Wrong   
    You have a severe misunderstanding of energy. Conservation of energy means that energy remains unchanged ***in a given frame of reference***. It doesn't mean that if you change the frame of reference that the energy will remain unchanged. A clear example is a particle that is at rest in an inertial frame of reference S. In S the total energy is zero. Now change to a frame S'' which is moving relative to S with speed v. in S' the total energy is the kinetic energy of the particle and has the value E = K = mv^2/2 which is greater that it was in S. But this does not mean that energy isn't conserved. By definition - conservation of energy is defined in a given frame of reference, i.e. it remains constant in that frame. It doesn't mean its constant in all frames or that it remains unchanged when you change to a new inertial frame.
     
    No wonder you thought you proved SR wrong - you don't understand conservation of energy.
  8. Like
    Pmb got a reaction from Moontanman in Magnetic Sphere   
    Howdy Moontanman! What a wonderfully simple and enlightening question! Thank you so much for posting it!
     
    I assume that what you have in mind is a magnetic monopole, correct? I'm sad to report that your intuition is way off. Let's redraw your sphere but this time we'll only have magnetic dipoles on a surface of a sphere. The result will be the same. This time instead of using bar magnets we'll use small loops of current. First do the surface of the north hemisphere. Notice that the currents on the interior will cancel out. When you've completed the entire top of the sphere you'll notice that the only current left is a single loop going in one direction. When you do the bottom hemisphere you'll get the same results. Put them together and you get no magnet at all.
  9. Like
    Pmb got a reaction from Moontanman in Gravity Defined   
    From what I've read of that URL this thread doesn't belong in this forum, it belongs in the Alternative theories forum.
     
    Since you asked for opinions here is mine: It's total garbage. Since you only had one semester of physics in college you lack the skills to understand all the mistakes that you made. There are far too many to list. At one point it's as if every sentence becomes nonsense. The entire page is basically a word salad.
     
    You use terms like "obviously" to refer to things that make no sense at all. I can't/won't tell you everything that's wrong with it so I'm going to leave it at that. If I got into it it would take far too much of my precious time, time that I use helping people understand real physics. Nothing personal. But before you start claiming a theory is wrong you really should learn physics first. Especially the theory you're claiming is wrong and before all of that learn the Philosophy of Physics most importantly.
  10. Like
    Pmb got a reaction from Moontanman in You Shouldn't Trust Wikipedia. It Even Says A Fever Can Cause You To Catch Fire   
    LisaL - Will you please do me a favor and post the link to where in Wikipedia that you read that? I went to https://en.wikipedia.org/Spontaneous _human_combustion. I did a search on that page for the terms fever and temperature and found nothing on each.
     
    If you don't mind me asking, to whom were you talking to anyway? What is ffs? If it's related to a fever then how did she know what that person's temperature was? Thanks.
  11. Like
    Pmb got a reaction from sanctus in I Mathematically Proved That Einstein's Relativity Is Wrong   
    I looked through your paper and found that it was filled with misconceptions in all cases. If you'd like I'd be more than happy to print out the entire paper, read it carefully and then write a post or series of posts (if there is a word limit for individual posts) to explain where you went wrong.
     
    Here's one as an example: On page 20 you argue "But R does not have any limit because it is distance. So if R > C then V > C."
     
    Surely you must have been aware that all these incredibly brilliant physicists who make relativity their life's work didn't let this one slip by them, do you? Your error is in your assumption that the radius of a rotating disk can be arbitrarily large. In fact it can't be. Such a disk is made of atoms. There are no atoms which can move at the speed of light so there is no atom in the disk which can be moving at a speed greater than or equal to the speed of light. This implies that the radius of any disk is limited by its angular velocity.  The faster a disk rotates the more mass each atom gains and therefore the greater the mass of the disk. If the angular velocity w is greater than w = c/R then the mass of those atoms becomes infinite which means it can't rotate that fast.
     
    Your comments which follow based on that are therefore wrong. Nothing can move at or faster than the speed of light other than massless elementary particles.
     
    So I'll read your paper and get back to you. Let me know if you'd like me to post all the errors that are in the paper.
  12. Like
    Pmb got a reaction from sanctus in Relativity Made Simple   
    A-wal: You really need to stop being as rude as you are. Your rudeness is rooted in the amount of arrogance that you've been displaying here. You've shown that anytime someone has pointed out an error that you've made, like I did, all you've been able to do is claim it was in fact their error and it was they who had a misconception. While it's quite clear to me that the rest of the forum knows this all to well it might be worth pointing it out to you one last time so that I may at least see if you're able to admit your mistakes. The following example demonstrates the mistake you made which you claimed was my misconception. I explained the following (the only mistake I made was writing "he" instead of "the" which I correct here)
     
     
    There was nothing in this statement that referred to any other frame of reference other than the car's frame of reference. To think it did meant that you weren't paying attention to the subject matter or the point being made.
     
    Therefore when you started saying "You can use either car or the road as a frame of reference .... there's two objects moving away from each other at 110 mph...." when that had absolutely nothing to do with my post or the subject I was talking about.
     
    I was clearly referring to Philip1182's post where he said
     
    which was a misunderstanding on his part since there is ---->>>> not one single frame <<<<---- in which light itself is traveling at something other than c. So I gave him an example which demonstrates that a car moving relative to a road at 55 mph is only moving at 555 mph relative to the road even though the rate of change of the distance between the two cars is changing at 110 mph.
     
    So not only did you miss the entire point that I made, and you were the only person to miss the point you found the need to be quite rude to do it and you remain quite rude even with the warnings you got. Let's see how long you maintain that attitude when I report each post you make with you being rude. Stop being rude and act more polite like the other members here are.
     
    My comment was in regards to post #2 where
     
     
    -------------
  13. Like
    Pmb got a reaction from sanctus in Relativity Made Simple   
    "What are you talking about?" - What a shame. It was so clear too. I was talking about observations being made ***in the frame of reference of the -->road<---*** and in that frame there is nothing moving at 110 mph with respect to the road. Please read more carefully next time and perhaps you'll understand.
  14. Like
    Pmb got a reaction from sanctus in Relativity Made Simple   
    When you fire two beams of light at each other its the "relative" change in distance between two objects. But that's not how velocity is defined. The velocity of an object is defined as its change in position relative to a particular frame of reference. E.g. a car can travel at 55 mph relative to the road. If a man is standing on he side of the road and one car is moving at 55mph in the +x direction and the other at 55mph in the -x direction then there is nothing moving at 110 mph. The only thing having to do with 110 mph is the distance between the two objects is changing at a rate of 110 mph. But one can't change to a frame in which one of the beams of light is at rest and measure the speed of the other beam.
     
    Note that the principle of relativity alone cannot be used to show that the speed of light is invariant. One needs a separate postulate for that. The second postulate used by Einstein was simply that, i.e. the speed of light is invariant. Another way to phrase it is that the proper mass of a photon is zero.
  15. Like
    Pmb got a reaction from sanctus in Relativity Wheel   
    re - time is no different than space
     
    Quite wrong. There is nothing in relativity which says or implies such a thing. This is a common misconception. Time is a dimension in spacetime. That doesn't mean that time and space are the same thing. Time is measured with a clock and space is measured with a rod. If time and space were actually the same thing then you could rotate a clock into a clock. Since we know such things are meaningful we can easily see that time is not the same as space. Einstein made this quite clear in an article he wrote in nature.
     
    Also the four dimensions are not at right angles to each other. That's not a physically meaningful statement. The only thing that can be at right angles are spatial axes. On a spacetime diagram you can draw the time axis at a right angle to a spatial axis if you use Cartesian coordinates. Only in a Cartesian coordinate system are the axes at right angles to each other.
     
    To draw a spacetime diagram you draw a horizontal axis with the +x direction to the right. Then you draw the time axis vertically, i.e. at a right angle to the x-axis. The worldline of a photon moving in the +x direction is a straight line making an angle of 45 degrees with the x-axis in the counter clockwise sense. This is only if you scale the time axis by plotting it as x0 = ct where t is time and c is the speed of light.
     
    Being able to see time dilation and Lorentz contraction on such diagrams requires much more work. You first have to superimpose the new axes over the old ones. The new x' axis will make an angle theta with the x-axis in the counter clockwise direction. The new time axis will make an angle theta with the old one in the clockwise direction. Events are then plotted in the new coordinate system by drawing lines parallel to the new axis. These lines won't be perpendiculars to the new axis though as they are when you change Cartesian coordinates from one frame to a new one rotated with respect to the first. Then you have to calibrate the axes which can be done using the invariant (ct)2 - x2 - y2 - z2 = (ct')2 - x'2 - y'2 - z'2
  16. Like
    Pmb got a reaction from CraigD in Maxwell's Law   
    That's because you're trying to use classical electrodynamics in the quantum domain. Physicists realized this problem over a hundred years ago and started making attempts to solve this problem. The result was a new theory called Quantum Mechanics (QM). In this theory one cannot think of electrons as moving. QM is all about measurement and what you don't measure doesn't exist. For example: until you measure the position of an electron it cannot be said to even have a position. If this seems weird to you then you're on the right track since it really should be weird. We don't have experiences on the quantum domain (i.e. the subatomic) so when we start learning about it we're learning about something we've never experienced before never will experience in the future.
     
    Since the charges don't have a position it doesn't have a velocity and thus it remains in a static state inside the atom. When the electron is shed out of the atom things change and when its moving with a bunch of others we can then start to detect magnetic fields. However that gets into quantum field theory which is something I'm not familiar with, yet.
  17. Like
    Pmb got a reaction from pgrmdave in Maxwell's Law   
    That's because you're trying to use classical electrodynamics in the quantum domain. Physicists realized this problem over a hundred years ago and started making attempts to solve this problem. The result was a new theory called Quantum Mechanics (QM). In this theory one cannot think of electrons as moving. QM is all about measurement and what you don't measure doesn't exist. For example: until you measure the position of an electron it cannot be said to even have a position. If this seems weird to you then you're on the right track since it really should be weird. We don't have experiences on the quantum domain (i.e. the subatomic) so when we start learning about it we're learning about something we've never experienced before never will experience in the future.
     
    Since the charges don't have a position it doesn't have a velocity and thus it remains in a static state inside the atom. When the electron is shed out of the atom things change and when its moving with a bunch of others we can then start to detect magnetic fields. However that gets into quantum field theory which is something I'm not familiar with, yet.
  18. Like
    Pmb got a reaction from CraigD in Gravity may be caused by time waves   
    As Janus said: Gibberish. You'd do best to ignore it.
  19. Like
    Pmb reacted to sanctus in Bannings   
    Not if posted in the proper section (="Alternative theories") and are tried to be supported not just stated.
  20. Like
    Pmb got a reaction from sanctus in Does Time Really Exist? Yes Or No?   
    What he claims is wrong. He doesn't know what he's talking. Nor does anyone who claims that time does not exist. There are more than one states of the universe. This phenomena is what we describe with the concept of time. To say that time is an illusion means that there is only one state of the universe and that nothing ever changes and that's emperically wrong.
     
    Your premise is wrong making you wrong as well.
  21. Like
    Pmb got a reaction from CraigD in Size Of The Universe   
    We compare the size of the universe with length standards defined on Earth.
     
    Since the Earth is in the universe just as we are there are no problems with a standard of length).
     
    It is quite forseeable that there are parallel universes. The universe is not defined as "all that exists" but is defined as "all the space that is reachable from any other place in the universe by a continuous line. Since such a line cannot reach parallel universes and those other units might have other stuff in it then we can't say that the universe contains everything by definition.
     
    There is a counter example of this on my website. Please see the diagram at
    http://home.comcast.net/~peter.m.brown/religion/the_word_god.htm
     
    (ignore the content of the page and condentrate only on diagram at the bottom.
     
    It's like an infinite sheet of rubber. One can easily imagine coordinate axes drawn on the surface and the distance between the lines increaseing with time. Think of a cloed universe. It's like the surface of a ballon. A spatiallyclosed universe is like the surface of a ballon. An increasing in size universe is like blowing the balloon up with air.
     
    There are two possible scenarios (a) the universe is spatially closed or (2) the universe is spatially open. An open universe means that the universe is finite in spatial extent whereas to be closed means to be of infinite spatial extent. A geometric plane is an example of an open space whereas the surface of a sphere is an example of a closed space. These examples are quite often used as analogies so I'll use them in this post as analogies too.
     
    The spatially open universe is infinite in size. A spatially closed universe is finite in size. A person in a closed universe is like an ant walking on the surface of a sphere. Since an ant can make measurements on the sphere (the length of the ant namked "Frank" is used as the unit length). We can then easily define the size of such a universe as well as the area on the surface
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