Jump to content


Senior Members
  • Posts

  • Joined

  • Last visited

  • Days Won


Posts posted by J.C.MacSwell

  1. at the moment there isn't enough matter acounted for in the universe to create the strong forces of gravity needed for the "big Crunch" to occur' date=' and so consequently it may not even happen and the universe continue to expand ([b']steady state theory[/b]) however i dont believe this. Dark matter must exsist in our universe somewhere...matter sucked into a black hole for instance, whole galaxies could have imploded in on themselves way back when the universe was "born".


    thats just my thoughts...


    The steady state theory (read model/s) has no big bang. One model had continuous creation of matter to balance the expansion, thus creating a steady state.

  2. There are problems in electrodynamics' date=' in which Newton's third law is violated... is one of them? <------ THAT'S THE WHOLE QUESTION. :)


    I was hoping to get more responses, but no one here wants to take this on. That's a shame.


    You are in space. Your spaceship is twenty feet away from you to your left, and at rest relative to you. You have in your posession a cylinder, copper wire, a battery, and an iron ring, they are parts of your jetpack which broke. You have 10 minutes left of oxygen, and there's no one on the ship to help you. What do you do?[/quote']


    Push some of that junk hard to your right! :D

  3. If the hole is between the poles and you neglect friction you will accelerate to the center starting at 0 velocity and maximum acceleration until you reach the center at maximum velocity and 0 acceleration. You would then reverse the process (acceleration wise) as you continue to the other pole and come to a stop (for an instant) before heading back.


    Other "direct routes" would include a corriolis (sp?) like "force" (pseudo force)which will deflect you against the sides of the hole.


    I forgot about the moon which would be significant. You can almost ignore the sun if you jump "today" or 6 months from now. There must be a path/tunnel that would exit you somewhere (near?) the Earth's surface if you jumped at the right time.

  4. If they slow down their clock speeds up[/b']. The also go off at some angle, so their path length increases. Both would make them less likely to reach the ground before they decay.


    1. We would see their clock speed up (due to velocity) if they slowed in our reference frame.

    2. We would see their clock slow down (due to acceleration) if they accelerated/deccelerated in our reference frame.


    So if they deccelerated relative to us "effect 1." would overwhelm "effect 2"?

  5. They are created in a collision, but not of a muon. Cosmic rays collide and produce pions, which subsequently decay to muons. I'm not sure how to account for collisions, but the ones that are detected still have a significant amount of energy, so the average acceleration wouldn't be that big. The ones that scatter with large energy loss would do so through a large angle and not be detected; the ones that scatter through a small angle can't have undergone a large acceleration.


    So if they deccelerate enough to "live longer" they are unlikely to reach the ground?

  6. Near the surface of the earth, the redshift is a part in 1016 per meter (g/c2). Negligible compared to the kinematic term as long as gh << v[sup']2[/sup]


    Isn't the deccelleration many, many times that in significance? Is it still negligible in comparison to the velocity time dilation?

  7. Yes the mean lifetime is statistical. Which means you can do statistical analysis of it. You take more than one data point.


    In the experiment' date=' there was a bias - more particles reached the ground than were expected to from a statistical standpoint, and was instead as predicted by relativity.[/quote']



  8. I haven't watched the experiment, so I can only guess - you'd get flux and energy measurements from taking data at various elevations, as well as from a lab setup, that allow you to deduce the lifetime of the muons vs their energy.


    Would there not be significant GR element (read non SR) due to decceleration?

  9. I'm on very shaky ground here. That was why I specifically specified a stellar black hole. You would be torn apart by the tides' date=' because the gravitational force would be dramatically different from one end of your body to the other. I'm sure someone here can do the math faster than it would take me to find the relevant equations, then check my answers a dozen times. (pretty please.)

    However, how large did you mean. I believe some see the Universe as being a black hole, and we are alive and functioning inside it. Of course, we didn't fall through the event horizon.....[/quote']


    Sorry, missed the "stellar".

  10. No, officially the second is defined as the time it takes for 9192631770 oscillations between the hyperfine states of an unperturbed Cs-133 atom.

    Would any/all perturbations decrease the number of oscillations? Or could it increase it as well?


    I'm wondering if it's a relativistic effect.

  11. Those pressure suits won't allow a human being to sustain an acceleration of 1000g will they? Something else is needed.


    I probably should have said' date=' "won't allow a human being to sustain a force of 1000g"



    Oops 1000g; my sphereship only does a little over 100 g! (we're going to need more funding :D )


    Edit: Let's be conservative and build the 100g sphereship first as a prototype and "proof of concept". :)

  12. React in what way? A black hole is a singularity. The density of matter in a stellar black hole may not be infinitely dense, but it is, arguably, unimaginably dense. Any distinction between 'particles' has been obliterated, so what are you actually asking?


    If you travelled past the horizon of a large enough black hole you would still be alive and functioning. Correct?

  13. Ok let S denote an inertial reference frame.

    Now' date=' let a photon be traveling along the x axis of S, in the direction of increasing x coordinates.


    Now, let S` denote a reference frame in which the photon is at rest. Let the origin of S` be the location of the photon.


    Let S and S` be in standard configuration. That means the positive x rays of both systems are parallel and point in the same direction, and the positive y rays are parallel and point in the same direction, and the positive z rays are parallel and point in the same direction.


    Let the origins of both frames coincide when t=t`=0.


    [b']Here are the Galilean transforms:[/b]x`= x-ct





    So the axes of S` aren't spinning in S. From which it follows that S` is also an inertial reference frame.



    Kind regards




    If this is insufficient, tell me what your objection is.


    Galileo was a genius. He tried to measure the speed of light by having an assistant on a distant hilltop "signal him back" to measure the speed of light.


    If you try this today they lock you up. :D

  14. Can a human being be magnetized?


    It has been suggested by some' date=' that if we want to accelerate human beings beyond the 6-8 g's, at which highly trained fighter pilots black out at, that the only way to do it, is to turn the human body into a magnet, so that the human being's body will not be subjected to internal stresses and strains which would tear the body apart.


    Is that the only way to do it?

    Is that even possible?


    If it is impossible, what is the most rapid proof proving so, so that it can be eliminated from consideration?


    For whatever it's worth, I myself don't think this idea will work.[/quote']


    OK since I blurted about the magnet I will explain a "ship" that will accelerate at 100g with humans aboard. I get all the "superstrength" exotic materials and all the energy and control of that energy as a given. In other words I do the easy part, the concept, and you do the hard part, the engineering and building. As a reward you get to try it out and be famous or infamous as the case may be.


    Start with a big (10 Earth diameters) hollow sphere with the passengers at the center supported by some symmetrical framework so that the net gravitational forces are zero.

    (You are building this far from any gravitational body)


    The passengers can slide inside a tube from the front to the back of the sphere/ship. All symmetrical so far, no net gravitational forces.


    With the passengers held at the center you fire your thrusters and begin to accelerate at 1g. Everybody is happy to be "back on Earth" weight wise.


    Controlling your speed you deccellerate to "dock" with a dense "100 Earth mass" which attaches to your "front". You now have a ship at rest, in whatever frame you have gotten to, and are not accelerating. You regret the price of the energy bill required to get your "100 Earth mass nose" into position but it is now part of the "ship". You will later realize how inexpensive it was after your first month or two of "trials".


    To accelerate forward you "release" the passenger slide allowing it to fall toward the nose then accelerate the ship to "catch up". At full 100g acceleration of the ship the passenger slide should be about 1 Earth radius from the centre of the "nose".


    To deccelerate (or even reduce acceleration) you must accelerate first to "distance" the passengers from the nose first. "Control" is essential to the safety of the passengers. The distance from the nose must be carefully matched to the acceleration/decelleration.


    How did I do? I guess I have a year to apply for a patent so since you're funding the engineering/building I might as well turn the rights over to you now (for a small fee, Tim Hortons coffee and tea biscuit would be about right). Anyway, be kind, this is the pseudo science thread. :D

  15. Two events occurs at the space point in a particular frame of reference and are simultaneous in that frame. Is it possible that they may be simultaneous in another frame?


    Only if the two frames are not moving wrt one another.


    Edit: I already think this is wrong, it depends on the spatial alignment of events and the direction of relative movement of the frames also.

  16. I


    You said create a "human magnet." I didn't understand that yesterday' date=' nor do I understand it now. But here is my question, we can move it to another thread if necessary:




    I didn't understand that yesterday, nor do I understand it now either. :D


    Open up a thread in pseudo science. We can discuss it there.

  17. How about understanding that it appears the same to observers in those frames.


    Stop taking this thread off-topic.


    Are you saying the speed of light is constant in all frames' date=' or do you mean just the ones that scientists agree that the speed of light is constant in?


    Or are you perhaps [b']defining[/b] a "frame" as that which the speed of light is constant in?


    Just a suggestion as I think this is a great forum with some very knowledgable and smart people on it (yourself included) but if we had a list of agreed definitions it could save us some grief and keep us on topic.


    I know I am as guilty as anyone in using the wrong terminology at times but I do not do it intentionally and try to "flag" it in some way if I'm unsure.


    Outside of inertial frames I cannot think of any others offhand that the speed of light is constant in.

  18. Where did you get that idea from?


    "Accelerate all parts of the body equally' date=' with no significant internal stresses" this seems correct.[/quote']


    Just a "blurt". I see no way of achieving it except in a "science fiction" sense as Phi pointed out. (alignment of all electron spins, Yadda, Yadda...)

    How did the sub propulsion system work? Or maybe charging the bodies and have an electrostatic field within the ship. (Careful not to electrocute them. :D )

  19. I'm not here to tell anyone they are wrong' date=' I actually need help on something which I am working on. There is no need to beat around the bush. I want to figure out a way to accelerate people from rest to 1000g, and then have that ship maintain that acceleration in the original frame in which the ship was at rest, but have their weight inside the ship be equivalent to their weight on earth, throughout the accelerative process.


    From your point of view this is impossible, but my questions would be along the lines of logic. What would have to be true, for this to be done. Which current theories of physics would permit it to be possible, and which current theories of physics wouldn't permit it to be possible. I have those types of questions.[/quote']


    It's nice that you're not trying to crush them! :D

  20. That depends on which QED you mean. Usually, when people put it at the end of what they think is a proof, it means "quod erat demonstratum", meaning "that which is to be demonstrated".


    LOL, I wondered on a few posts about the QED "reference"

  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.