OceanBreeze 410 Posted May 10, 2019 Report Share Posted May 10, 2019 ^^^^^^^^ Link to post Share on other sites

MikeBrace 4 Posted May 10, 2019 Report Share Posted May 10, 2019 The "chink"is a gaping chasm.If you want to see the chasm in SR, then look at the first postulate of Einstein's 1905 paper.The Postulate is that light always travels at a constant speed. But later in the paper, in order to develop his hypothesis, he quietly slips in a SECOND claim, which is NOT RATIONAL. That claim is that the speed of light will always be recorded as 300000000m/s REGARDLESS of the velocity or even direction of the recording device! This is clearly impossible. How could we obtain the same fixed valued for C whether the detector is stationary, or when its moving with the lights at any speed, and also even when moving in the exact opposite direction to the light vector at any speed? Physicists need to explain how this is possible, which they never even attempt to do. The above quote is just the tip of the iceberg when it comes to the discussions in this post, and how they can go so badly astray and end up as bullshit. I use this post as not because it is in error, because it (like so many other posts in this thread) keep basing their arguments on informal fallacies; in this example it's the speed of light. Many on this thread keep thinking that the speed of light is a constant and the arguments based on this assumption are sound physics. I hate to break the news, but scientist have long ago figured out a way to slow light down, and I am talking about slowing it down to not just a crawl, but stopping photons in mid-flight altogether. Need proof? Just so some detective work. You may find that on the Jan 24, 2001 the Harvard Gazette reported that they got it down to 36 mph … then still slower later on. CBS talked about it on 19 Feb, 2001. Like one of the articles so eloquently said: …"the speed of light was considered one of the universe’s great constants. Albert Einstein theorized that light cannot travel faster than 186,282 miles per second. No one has proved him wrong, but he never said that it couldn’t go slower." If y'all really want to cut the bullshit out of physics - get your ducks in a row first, then make your point. Anything less is just bullshit. Link to post Share on other sites

ralfcis 43 Posted May 10, 2019 Report Share Posted May 10, 2019 OMG Mike, light just happens to travel at the speed limit of speed in a vacuum which for brevity is called the speed of light. Link to post Share on other sites

Sherwood 1 Posted May 11, 2019 Report Share Posted May 11, 2019 (edited) The SRT pdf at trybasics is difficult to follow and unnecessarily complicated. with a = v/c and u/c = 1/gamma, i.e. the clock ticks slower, the faster it moves past observer A. This phenomenon is not restricted to clocks but applies to all processes involving light interactions. "the clock ticks slower the faster it moves past observer A." It is also moving at different speeds past various other observers such as observers D,G,Q,M,K, etc., etc., who are probably moving at different speeds with respect to the clock and each other. Thus the clock has to read different times with respect to each that is at a different velocity. Difficult for one clock. 'Time dilation' exists only in the mathematics of SR, not in reality. Light starts out in a spherical direction from a source at speed c. (If light 'travels at speed c in all reference frames', it certainly travels at speed c from its source.) Something (object) moves with respect to the light source, call it in the horizontal direction. Then the 'vertical' (perpendicular) portion of the light has moved distance (I=ct) from the source at speed c for time t. Meanwhile, the object has moved the horizontal distance x'. So now the light is the vertical distance I plus the horizontal distance x' from the object for a total distance of H=(x^{2}+I^{2})^{1/2} The sum of the vertical distance (I) plus the horizontal distance (x') is (H). The speed of the light relative to the object (or vice versa) is obviously the distance (H) divided by the time (t) which could be called (c') in order to differentiate it from the speed c = (I/t) of the light with respect to its source. At the very least one must agree that distance (H) is greater than distance (I). If you insist (postulate, assume, etc.) that the speed of the light is the same both with respect to the light source and the object, then you end up with I/t = c = c' = H/twhich is obviously not true since H>I and therefore c'≠c. If at this point you simply get around the inequality by changing the time in the object's reference frame to (t'), then you have just created Einsatrein's theory of Special Relativity!! Now, I=ct and H=ct'and all the equations and concepts of SR follow directly. E.g., the Interval equation changes from I^{2} = ((c't)^{2 }- x' ^{2}) in Newtonian Mechanics (NM)to I^{2} = ((ct')^{2 }- x' ^{2}) in Special Relativity (SR)and the gamma function (g), which can also be written (H/I), changes from (H/I)=(c't/ct) in Newtonian mechanics (NM)to (H/I)=(ct'/ct) in Special Relativity SR. From this point, all the equations and concepts of SR can be derived. The discussion in post #96 is more complete, although the format of the posting leaves a lot to be desired. Edited May 11, 2019 by Sherwood Link to post Share on other sites

GAHD 75,062 Posted May 11, 2019 Report Share Posted May 11, 2019 Light starts out in a spherical directionLOL. NO. Not spherical. Try again? Link to post Share on other sites

Sherwood 1 Posted May 11, 2019 Report Share Posted May 11, 2019 LOL. NO. Not spherical. Try again? Maybe I should have said, "An omnidirectional light pulse leaves its source at speed c." In which case in the reference frame in which the source is not moving I would consider a sphere the appropriate description, since at any time the distance of the light from the source would be I=ct which would also equal the radius of a sphere of radius r=I=ct. The post is about the portion of the light, a disc actually, traveling perpendicular the the direction of motion of the object. Any object will be moving perpendicular to some 'disc' of light from an omnidirectional light pulse. Link to post Share on other sites

GAHD 75,062 Posted May 11, 2019 Report Share Posted May 11, 2019 (edited) Maybe I should have said, "An omnidirectional light pulse leaves its source at speed c." In which case in the reference frame in which the source is not moving I would consider a sphere the appropriate description, since at any time the distance of the light from the source would be I=ct which would also equal the radius of a sphere of radius r=I=ct. The post is about the portion of the light, a disc actually, traveling perpendicular the the direction of motion of the object. Any object will be moving perpendicular to some 'disc' of light from an omnidirectional light pulse.That's not how light works. Edit: I'm going to point you to a few keywords that will probably fix some serious misunderstandings . "Interferometer" "Bell's Theorem" Many on this thread keep thinking that the speed of light is a constant and the arguments based on this assumption are sound physics. I hate to break the news, but scientist have long ago figured out a way to slow light down, and I am talking about slowing it down to not just a crawl, but stopping photons in mid-flight altogether.Side note: Light is not "stopped" it's "contained" in the experiments you're talking about. IIRC one of them works off of induced refraction essentially turning the media into a mirror/lens, and the other one "absorbs" the photons into electrons which can then be dropped back to their ground state following normal (Stimulated Emission of Radiation) rules observable in any LASER system. It's cool, but it's NOT actually changing the speeds involved of any photons, it's just altering trajectory and re-emission times. Edited May 11, 2019 by GAHD feeling kind Link to post Share on other sites

Sherwood 1 Posted May 11, 2019 Report Share Posted May 11, 2019 - I don't believe that space-time is a physical entity. It's OK for Minkowski, a mathematician, to believe on it in the mathematical world. But space and time have no material properties and can't be subjected to effects of physical actions. They are mathematical definitions!! You might find this interesting. Minkowski's spacetime, often written s, is related mathematically to the Special Relativity (SR) Interval equation (I) as follows: I^{2} = –s^{2} where the distances in s are expressed in 3 dimensions but can be expressed in one dimension by rotation of coordinates and I^{2} = (ct)^{2} – x^{2} = (ct')^{2} – x'^{2} = (ct'')^{2} – x''^{2} = (ct''')^{2} – x'''^{2} = …Considering various objects (and their reference frames) moving in one direction at various speeds with respect to the light source, I is the distance the light has traveled perpendicularly to this direction from its source for time t presumably at speed c. It is the same distance for all of these reference frames. In the source frame, the source is not moving so the perpendicular light ray(s) do not change their x position. Therefore, x equals 0 in that frame and I is simply this perpendicular distance the light has moved during 'proper time' which is the same as Newtonian time. In SR, the transform equations show that SR 'time' is a function of Newtonian time, velocity, and location. The SR quantity that is the same as Newtonian time is (I/c). I hope this helps. My other posts may help. The discussion in post #96 is more complete, although the format of the posting leaves a lot to be desired. Link to post Share on other sites

rhertz 44 Posted May 11, 2019 Report Share Posted May 11, 2019 (edited) This is one of the solutions, post 1905_Einstein.Spoiler: It's dirty and fallacious, but it's widely used. This derivation can be watched here: 1) Assume that there are two reference frames, S and S', at which distance and time are (x,t) and (x',t') respectively. S' moves away from S at a constant velocity v. 2) S and S' motions are under only one axis, which contains x and x' positions (the other cartesian axis always verify positions y=y' and z=z'). Assume that (x,t,v) and (x',t',v) verify a transformation: x' = K (x - vt) , and that, for linear simmetry: x = K( x' + vt') being K a factor to be found. Replacing x' into x equation, it gives: x/K = Kx - Kvt + vt' vt' = x/K - Kx + Kvt Dividing by v, it gives t' = x/(vK) - Kx/v + Kt = Kt - Kx/v (1 - 1/K^{2}) 3) Also, synchronizing frames clocks at t=t'=0 with a flash of spherical shape, it is verified afterwards that: x = ct and x' = ct' (second postulate of STR) then for x', ct' = K (ct - vt) = Kt (c-v) and, for x, ct = K (ct'+vt') = Kt' (c+v) multiplying both sides of the last two equations, it gives c^{2} tt' = K^{2} tt' (c^{2}-v^{2}) or K^{2} = c^{2}/(c^{2}-v^{2}) or K = (1 - v^{2}/c^{2})^{-1/2} , which is the Lorentz Gamma Factor. 4) replacing K value in the former formula t' = Kt - Kx/v (1 - 1/K^{2}) it gives t' = Kt - Kxv/c^{2} = K (t - xv/c^{2}) = t - xv.c^{-2}/(1 - v^{2}/c^{2})^{1/2} , Lorentz transform for time t' as function of t extracting t, it gives t = t' + xv.c^{-2}/(1 - v^{2}/c^{2})^{1/2} , Lorentz transform for time t as function of t' Also, replacing K in x' = K (x - vt), it gives Lorentz transform of x' as function of x. Finally, replacing K in x = K (x' + vt'), it gives Lorentz transform of x as function of x'. ---------------------------------------------------------------------------------- Don't blame me. Blame relativists that polludes Internet and books with things like those above. Edited May 11, 2019 by rhertz Link to post Share on other sites

sluggo 47 Posted May 11, 2019 Report Share Posted May 11, 2019 rhertz#241;I don't label people, since the truth of a statement is in the statement, not the one who states it. Sometimes they are merely repeating something they heard or read. With that, there is the possibility that the statement was false or they misinterpreted it. I didn't see O. Heaviside in your list, and purposely mention him as an example of those in the background, who contribute to new ideas (work of Maxwell and Einstein), without any recognition. In general my interest in the personal life of authors/inventors is the history that lead them to the production of their idea, including eccentricities, as with Tesla! Great ideas but with a dark side.Contrary to popular belief, science is philosophy augmented with measurement, its verification tool. Scientists graduate with a Ph.D.The proof of a theory is via measurements, not personality.As to Einstein and relativity, I would suggest spending time researching the experimental evidence that supports his theories. One link is: www.edu-observatory.org/physics-faq Link to post Share on other sites

rhertz 44 Posted May 11, 2019 Report Share Posted May 11, 2019 rhertz#241; I don't label people, since the truth of a statement is in the statement, not the one who states it. Sometimes they are merely repeating something they heard or read. With that, there is the possibility that the statement was false or they misinterpreted it. I didn't see O. Heaviside in your list, and purposely mention him as an example of those in the background, who contribute to new ideas (work of Maxwell and Einstein), without any recognition. In general my interest in the personal life of authors/inventors is the history that lead them to the production of their idea, including eccentricities, as with Tesla! Great ideas but with a dark side. Contrary to popular belief, science is philosophy augmented with measurement, its verification tool. Scientists graduate with a Ph.D.The proof of a theory is via measurements, not personality.As to Einstein and relativity, I would suggest spending time researching the experimental evidence that supports his theories. One link is: www.edu-observatory.org/physics-faq You are correct with your observation about Heaviside, and it is a big mistake that I didn't include his name within the notable ones. I read Heaviside's biography last year, because I seeked it. For me, Heaviside was a genius at physics, electromagnetism and electrical engineering. I knew of him first, long time ago, for hisHeaviside's Echelon which, along with Dirac's Impulse Function, are fundamental for electrical and electronic engineers to analyzetemporal and frequential behaviors of a black box excited with one of these electrical signals (which have specific instruments togenerate them, as well as to analyze the time-frequency response in TRANSIENTS (using Laplace instead of Fourier). Not having any formal degree (he had plenty honoris causa degrees) and being extremely excentric (and poor) didn't help Heavisidepersonal marketing as others (like Faraday did). Also, didn't help that he lived almost as an hermit and (as I read), his final years werefilled with sad experiences and he WAS FORCED to accept a "pension" from the state (I don't know the proper name of this pension). He died in an undeserved way, and has been almost erased from history of physics by the "community of historians", who re-writehistory following a hidden agenda. He went into oblivion at the current technical bibliography, and didn't survive into the pop cultureof science and its icons. Another example (on the technical side) is Nikola Tesla, whose figure endures along history because he wasiconic in his excentricity and his "supressed inventions". Tesla became a popular myth because of the power of the US MSM.Heaviside did poorly along history, because of the classist MSM at Britain. But both deserve my utter respect. I know that Heaviside was involved into relativity even before Lorentz, with whom we worked and probably enlighted. There was a trio:Heaviside-Hertz-Lorentz, who took Maxwell electromagnetism and transformed his theory using vectorial algebra, subject that I understandhad Heaviside as one of his creators and main advocates. I also remember the Heaviside equations for transmission lines, which were foundational for the nascent electrical engineering as we know it today. With just this work, it was enough to make him famous, as it opened the door to the understanding of how electrical signals are affected while travellingalong transmission lines. His theory was fundamental for Pupin, a physicist who invented the "pupinitization" of telephone lines, allowing to extend itscoverage for about 100 Km, and all of this before the active amplifier. But history of science is UNFAIR. For instance (and there is something weird here): experimental physicists and engineers rank very low compared withtheoretical physicists. This is unforgivable for me. Link to post Share on other sites

Sherwood 1 Posted May 11, 2019 Report Share Posted May 11, 2019 3) Also, synchronizing frames clocks at t=t'=0 with a flash of spherical shape, it is verified afterwards that: x = ct and x' = ct' (second postulate of STR) This is exactly where Special Relativity (SR) goes wrong. The second postulate implies that something can go the same speed in both of two moving reference frames moving with respect to each other. The something, light or whatever, will travel different distances during the time involved. Therefore the velocities are different. x=ct and x'=c't. This is true for anything at any speed. My car can't be going the same speed with respect to everything else in the universe moving at various speeds and yours can't either. Neither can light or anything else. However if you postulate (insist, assume, etc.) that it can, then you get the math of SR--with c being the speed of my car (or yours). Also c seeming to be a maximum speed and the other oddities of SR.I'm running in the forest so your clock slows down! SR math can 'solve' problems because it is actually a 1:1 transliteration of Newtonian Mechanics (NM). Every NM depiction can be turned into a SR depiction and vice versa. See previous posts about this. Link to post Share on other sites

Sherwood 1 Posted May 12, 2019 Report Share Posted May 12, 2019 "Nothing can go faster than light speed c." SR transform equationx' = g(x+ut) = g(u/c)ct + gxwhere g is the SR gamma function.Let x' be traveling past x=0. A light pulse travels for 1 microsecond at speed c=300 million meters/sec in the unprimed frame. I=ct equals 300 meters. Assume the speed of the prime frame is u/c=0.8. Then g=5/3. Therefore x' equals (5/3)(0.8)ct or 400 meters. So the object traveled x'= g(u/c)(ct) = (5/3)(0.8)300 = 400 meters while the light traveled (ct)=300 meters. Looks like 'faster than light' to me. But the SR speed u was only 0.8c. Newtonian Mechanics (NM) version:Object traveled 400 meters while light traveled 300 meters at 300 million meters/sec.(x'/t) = v(x'/ct) = (v/c) = 400/300 = 4/3v = (4/3)cTransliteration of SR to NM:v = guwhere v is NM velocity and u is SR velocity and the two are never ever the same, although they approach each other at low speeds. u/c g v=g(u/c) 0.9 2.294157 2.064742 0.99 7.088812 7.017924 0.999 22.366272 22.349058 0.9999 70.712446 70.705375 Link to post Share on other sites

Sherwood 1 Posted May 12, 2019 Report Share Posted May 12, 2019 Reason #2: "Nothing can go faster than light speed c." Special Relativity (SR) Interval equationI^{2} = (ct')^{2}- x'^{2}(ct')^{2}= x'^{2}+ I^{2} u' = x'/t'(u'/c) = (x'/ct') = x'/(x'^{2} + I^{2})^{1/2}Obviously u'/c can never equal 1.0 But according to SRx' = g(x + ut) = g(u/c)ct + gxWhen x=0, ct=I, the distance the light traveled at speed c for time t.The ratio of the distance the object traveled, x', to the distance light traveled, I=ct, is g(ul/c) which approaches infinity as u/c approaches 1.0 Link to post Share on other sites

fahrquad 82 Posted May 12, 2019 Report Share Posted May 12, 2019 What are you driving, a horse and buggy? Nah, its a black 2010 Dodge Challenger SE with the 250hp 3.5 liter V-6 engine. Later models had the 3.6 liter Pentastar 305hp V-6 engine. To the best of my recollection the acceleration was pretty decent, but then I haven't driven in almost 2 years. That whole dying twice thing kind of took up a lot of my time. My wife's 2017 Toyota Corolla is light on the G's, and my 1974 MG Midget did 0-60mph in a week or so when I was still driving it. Most of the cars on the market are not GT-350's, Ferraris, Porshes, Superbirds, or Shelbys and are anemic by comparison. Link to post Share on other sites

ralfcis 43 Posted May 12, 2019 Report Share Posted May 12, 2019 Sherwood you're confusing Yv with v. v is limited to c but Yv is limitless. v=x/t, Yv =Yx/t =x/t'. At .8c, Y=5/3 so Yv=4/3c but Yc in that frame is 5/3c. It's all a matter of perspective and Yv or Yc is the proper distance travelled over the dilated time of the depicted moving frame from the depicted stationary frame's perspective. See my last posts in the relativity and simple algebra thread for more details. Link to post Share on other sites

rhertz 44 Posted May 12, 2019 Report Share Posted May 12, 2019 "Nothing can go faster than light speed c." SR transform equationx' = g(x+ut) = g(u/c)ct + gxwhere g is the SR gamma function.Let x' be traveling past x=0. A light pulse travels for 1 microsecond at speed c=300 million meters/sec in the unprimed frame. I=ct equals 300 meters. Assume the speed of the prime frame is u/c=0.8. Then g=5/3. Therefore x' equals (5/3)(0. 8)ct or 400 meters. So the object traveled x'= g(u/c)(ct) = (5/3)(0.8)300 = 400 meters while the light traveled (ct)=300 meters. Looks like 'faster than light' to me. But the SR speed u was only 0.8c. Newtonian Mechanics (NM) version:Object traveled 400 meters while light traveled 300 meters at 300 million meters/sec.(x'/t) = v(x'/ct) = (v/c) = 400/300 = 4/3v = (4/3)cTransliteration of SR to NM:v = guwhere v is NM velocity and u is SR velocity and the two are never ever the same, although they approach each other at low speeds. u/c g v=g(u/c) 0.9 2.294157 2.064742 0.99 7.088812 7.017924 0.999 22.366272 22.349058 0.9999 70.712446 70.705375 I hear you, But you must understand how Einstein prepares his sophism of Simultaneity by reading carefully his explanation, from his original paper (in English):I quote here the main part, which he prepares for his § 2. On the Relativity of Lengths and Times Excerpt from the original 1905 paper: I. KINEMATICAL PART§ 1. Definition of Simultaneity .......................We have so far defined only an “A time” and a “B time.” We have not defined a common “time” for A and B, for the latter cannot be defined at all unless we establish by definition that the “time” required by light to travel from A to B equals the “time” it requires to travel from B to A. Let a ray of light start at the “A time” t_{A} from A towards B, let it at the “B time” t_{B} be reflected at B in the direction of A,and arrive again at A at the “A time” t'_{A}.In accordance with definition the two clocks synchronize if t_{B} − t_{A} = t'_{A} − t_{B}. (Here resides the mathematical trick he uses later. By doing so, he eliminates "v" from the c+v and c-v expressions, so he obtains a round trip time t'_{A} = 2T_{B} if T_{A}=0, which is perfectly valid because he starts measuring time differences since T_{A})We assume that this definition of synchronism is free from contradictions, and possible for any number of points; and thatthe following relations are universally valid:—1. If the clock at B synchronizes with the clock at A, the clock at A synchronizes with the clock at B.2. If the clock at A synchronizes with the clock at B and also with the clock at C, the clocks at B and C also synchronize with each other. ................... Now he finishes § 1 In agreement with experience we further assume the quantity2AB/(t'_{A} − t_{A}) = c, (Here is trickery is more evident. Adopting t_{A} = 0 as before, you get c = 2AB/t'_{A} = AB/t_{B} . In this way, he is anticipating that c has the same value either in the first lapse when the mirror is hit or in the second lapse, when the light beam bounces back from the mirror to its origin A. Clever?)to be a universal constant—the velocity of light in empty space. .............................. End of excerpts from § 1 Now, pay attention to the mathematical and logical crime he commits at point § 2, using § 1. § 2. On the Relativity of Lengths and TimesThe following reflexions are based on the principle of relativity and on theprinciple of the constancy of the velocity of light. These two principles we defineas follows:—................................ We imagine further that with each clock there is a moving observer, and that these observers apply to both clocks the criterion established in § 1 for the synchronization of two clocks. Let a ray of light depart from A at the time t_{A}, let it be reflected at B at the time t_{B}, and reach A again at the time t'_{A}. (Now he includes "v" in the famous round trip, because he needs the factors (c - v) and (c + v) toobtain the famous c^{2}-v^{2}, otherwise impossible to appear. But, doing so, he violates his own 2nd. postulate:speed of light dependent on the motion v of the source or reflexion of the source). Taking into consideration the principle of the constancy of the velocity of light we find thatt_{B} − t_{A} = r_{AB}/(c − v) and t'_{A} − t_{B} = r_{AB}/(c + v)where r_{AB} denotes the length of the moving rod—measured in the stationary system. Observers moving with the moving rod would thus find that the two clocks were not synchronous, while observers in the stationary system would declare the clocks to be synchronous. ........................................ The rest is mathematical garbage, as he struggles to get the Gamma factor, which he PURPOSEDLY calls Beta! Besides, if you follow the tricky derivation, it follows the premises and even the notation of Woldemar Voigt for themoving reference. At the end of the paper, he uses the term "longitudinal mass". This particular term was unheard by then, except atonly one writing: the Lorentz's 1904 paper! I stop here, as I don't want to bash STR (here). Link to post Share on other sites

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