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#361 |
Penultimate Amazing
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#362 |
Muse
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#363 |
Penultimate Amazing
Join Date: Apr 2004
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#364 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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Pick one scenario. Describe it clearly. Use events and give a clear description for each event. Show the maths. Stick to maths that is allowed in the theory.
Then see if there is a problem. |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#365 |
The Clarity Is Devastating
Join Date: Nov 2006
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Posts: 17,293
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A zømbie once bit my sister... |
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#366 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#368 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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Are you saying that your second diagram there is the first diagram from the point of view of that inertial traveller shown by the light blue line?
I think not. But again, I have pointed out again that non-inertial paths can't be treated like inertial paths and you respond yet again by trying to transform a non inertial path like an inertial path. |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#369 |
Philosopher
Join Date: Aug 2002
Location: Denmark
Posts: 6,105
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I am not qualified to have an opinion on these matters, but as far as I can gather, plenty of posters here are qualified, and I even believe you have got their qualified answers. To me, it certainly looks as if you studiously ignore the answers, and just repeat your questions with new twists. |
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Steen -- Jack of all trades - master of none! |
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#370 |
Lackey
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I wish I knew how to quit you |
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#371 |
Muse
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#372 |
Lackey
Administrator
Join Date: Aug 2001
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It will definitely be yes or not.
Now I've answered that how about you answer the following questions: Why do you think you have spotted a mistake that has gone unnoticed by generations of physicists and mathematicians? Why do you think you are not able to convince anyone of your correction to established physics? |
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#373 |
The Clarity Is Devastating
Join Date: Nov 2006
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What light blue line? The one curving downward from above the t = T line, with an arrow head pointing vaguely toward event P, and with the three enormous red exclamation points next to it? No, that's not following the same world line. (I'd ask, "same world line as what?," but it's not following any valid world line so the answer is no regardless.) That's the only blue line in this diagram. Do you even look at the diagrams you repeatedly post? |
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#374 |
Muse
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#375 |
Muse
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#376 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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How are they related? Where is P on your second diagram?
What are the values in the first diagram?
Quote:
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#377 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
Posts: 27,671
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SDG continues to show ignorance about the textbook images he spamming the thread with.
No one with eyes will agree. The light blue line is a straight line. The dark red one is a curved line. They are different worldlines connecting the same events in spacetime.
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NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
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#378 |
Penultimate Amazing
Join Date: Mar 2008
Location: New Zealand
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24 August 2020: A "unrealistic uniform gravitational acceleration" in the equivalence principle lie.
For a start Einstein did not come up with the equivalence principle out of thin air: "Something like the equivalence principle emerged in the early 17th century, when Galileo expressed experimentally that the acceleration of a test mass due to gravitation is independent of the amount of mass being accelerated.". Einstein stated the equivalence of inertial and gravitational mass as the equivalence of gravitational fields and acceleration locally. The lie is that uniform gravitational fields are unrealistic. The equivalence principle explicably states that the equivalence applies locally which is a scale where divergence of gravitational field lines can be ignored, i.e. the gravitational field is uniform. For example, realistically we can ignore tidal effects between our feet and head and treat Earth's surface gravity as uniform. On the same Wikipedia page is Tests of the Einstein equivalence principle (and th weak and strong principles). Of course the indirect evidence that the equivalence principle is that fact that general relativity works extremely well ![]() |
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NASA Finds Direct Proof of Dark Matter (another observation) (and Abell 520) Electric comets still do not exist! |
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#379 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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SDG,
So let's take your top diagram and put some description to it, correct me if I have misunderstood you: A (t=0 x=0) Traveller 1 (red) has v=0 and begins moving P (t=4,x=3.464) Traveller 1 (red) has reached v=0 and continues moving in the opposite direction B (t=8,x=0) Traveller 1 (red) has again reached a velocity of zero Traveller 2 (blue) is moving with a constant velocity of 0.866c and is at the same position as traveller 1 at A and P. And then plot that and put it from the perspective of the initial and final velocity of traveller 1 (left) and of traveller 2 (right): ![]() A=(0,0,0,0) A'=(0,0,0,0) P=(4,3.464,0,0) P'=(2,0,0,0) B=(8,0,0,0) B'=(16,-13.856,0,0) Note that the accelerating traveller must come very close to the speed of light at mid journey in order to arrive at the same place and time as the inertial traveller. |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#380 |
Muse
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#381 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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Now you are drawing a completely different diagram with events not shown on the original and not following any of the conventions of relativity diagrams.
This is some new theory of your own?? And where did you mention a platform in the first diagram you provided? Where is P on the new diagram you show?? Did B move?? Again, state your scenario completely and clearly defined events and world lines and properly drawn diagrams with events consistently drawn on each and no extraneous letters or symbols. |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#382 |
The Clarity Is Devastating
Join Date: Nov 2006
Location: Betwixt
Posts: 17,293
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A zømbie once bit my sister... |
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#383 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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SDG,
You provided this (a text book diagram with non-specific times and distances) and some extra stuff drawn on it: ![]() I suggested that this is what you mean by it: ![]() A=(0,0), P=(4,3.464), B=(8,0) Now what have I missed in my diagram, that is in your diagram above it and relevant to the point you are making? Where is the platform in this diagram? |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#384 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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Do I understand this platform to be 3.434 cs long and start at x=0?
If so then we can represent the front of the platform with a world line, shown here in green. Platform frame on the left, blue inertial traveller frame on the right: ![]() A (t=0 x=0) Traveller 1 (red) has v=0 and begins moving P (t=4,x=3.464) Traveller 1 (red) has reached v=0 and continues moving in the opposite direction B (t=8,x=0) Traveller 1 (red) has again reached a velocity of zero Traveller 2 (blue) is moving with a constant velocity of 0,866c and is at the same position as traveller 1 at A and P. Platform is 3.464cs long and begins at x=0. Front of platform world line shown in green A=(0,0,0,0) A'=(0,0,0,0) P=(4,3.464,0,0) P'=(2,0,0,0) B=(8,0,0,0) B'=(16,-13.856,0,0) |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#385 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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So, from each point of view,
The inertial traveller has covered 3.464 cs in 4 s or; The inertial traveller has remained in place and the front of the platform has covered 1.732 cs in 2 s. |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#386 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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SDG
The main problem with your diagram below (apart from the fact that it does not follow any of the conventions of spacetime diagrams) is that your light lines are wrong. In the non-inertial frame of the accelerated traveller, if the time axis is straight then he must be coming under three separate gravitational fields and so at that light line won't be in a straight line on your diagram. Calculate some light paths for those areas and you will find that nothing has exceeded the speed of light:
Originally Posted by SDG
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#387 |
Muse
Join Date: Jul 2018
Posts: 959
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Robin, It is buried in the first pages of this thread, B and P are the same events. ![]() Here is the platform, the green horizontal lines. If you compare it to the left side diagram below and B=P. The traveler twin stops at P/B event. The ct' stays at x=3.4641cs in the platform frame. The ct axis is at x'=-3.4641cs'. How long for the ct to cross 3.4641cs' distance to the left in the blue inertial frame that goes through A, P events? Your other diagrams do not capture stopping at P. When the stop happens than x, x' rulers are equal and ct, ct' axes are parallel. ![]() |
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#388 |
Muse
Join Date: Jul 2018
Posts: 959
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OK, so A'->P' 2s' and P'->B' 14s'. The traveling twin is 2x older. The left diagram, the red line goes straight up after P because we wan to know what happens when the traveling twin stops at P. The axis t is supposed to be parallel to t' after 2s' or 4s' and it is x'=-3.4641cs' to the left. |
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#389 |
Penultimate Amazing
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#390 |
Penultimate Amazing
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#391 |
Muse
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#392 |
Penultimate Amazing
Join Date: Apr 2004
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#393 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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So, to be clear, we have:
![]() Where A (0,0) Twin 2 (blue) accelerates away to the right B (4,3.464) Twin 2 has decelerated to 0 and remains at v=0 C (4,0) Twin 1 notes 4 seconds passing on clock Twin 1 Green world lines, front and back of platform Twin 2 Blue world lines, front and back of train |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#394 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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So from the point of view of the inertial traveller (shown in orange) our million kilometre long train is doing something like this:
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#395 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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And if we absolutely must try to shoehorn the proper time path of the accelerated one million kilometre train onto one of these diagrams, it would look something like this, I believe:
![]() Note that there is no A', B' or C' since at these events everything is travelling at the same velocity. However the platform clock will show 4s in either case and the train time will show approximately 2s at B in either case. A stationary clock that started at the front of the platform at t=0, x=3.464 would show 4s at B |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#396 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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Interesting to know if the million kilometre long train is being pulled or shunted.
Forces can only propogate through any material at the speed of sound for that material. So the scenario is kind of silly in practical terms. |
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#397 |
Schrödinger's cat
Join Date: May 2004
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"If you trust in yourself ... and believe in your dreams ... and follow your star ... you'll still get beaten by people who spent their time working hard and learning things" - Terry Pratchett |
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#398 |
Penultimate Amazing
Join Date: Apr 2004
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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#399 |
Penultimate Amazing
Join Date: Mar 2009
Posts: 17,729
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Actually that just illustrates what is dumb about it: That presupposes that there is such a preferred frame. The whole POINT of relativity is that there isn't. ESPECIALLY in SPECIAL relativity.
In GR you can differentiate between inertial and non-inertial, but even then it doesn't automatically mean that one is more "right" than another. It may be easier to do the maths in one than in the other, but that's where any claims of being the right one stops. But in SR, you don't even have that: all inertial frames are just as good. There is no such thing as a rest frame, nor any such thing of there being any frame that everyone must agree that it has the right measurements. Two frames can be at rest relative to each other, or not, but that's about it. Saying that the train is moving with speed v relative to the station, or that the station is moving with speed -v relative to the train is equally true. And not just saying it. Fundamentally, none of the two frames has any claim to being the one true frame that everyone has to agree on. Both are exactly as good as each other. That's the whole POINT of relativity. That's why it has "relative" in the name: it's all relative. As in, relative to whatever frame you're using. I.e., it's just as valid to say that Ross 128 is 11 ly away in the frame of Earth as it is to say it's 5.5 ly away in the frame of someone moving at v=0.866c. There is no one true distance. |
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Which part of "Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn" don't you understand? |
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#400 |
Penultimate Amazing
Join Date: Apr 2004
Posts: 12,881
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Fix up of previous graph:
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The non-theoretical character of metaphysics would not be in itself a defect; all arts have this non-theoretical character without thereby losing their high value for personal as well as for social life. The danger lies in the deceptive character of metaphysics; it gives the illusion of knowledge without actually giving any knowledge. This is the reason why we reject it. - Rudolf Carnap "Philosophy and Logical Syntax" |
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