Capiert

That's what I got out of it, my words.

I think what he means is Einstein's Ether (concept) (which he (=Einstein) believed physics absolutely needed) was a frozen sea of photons. -Leiden University lecture 1922.

There is no point in (wrongly) insisting KE is a vector, KE is NOT a vector, KE/v is a vector instead. i.e. (average) mom(entum). Errors as those are useless & misleeding=contraproductive =(more than) double_trouble (to correct).

I'd like to make a formal apology for the confusion (I had) with work. I used books from the 1950's (used in German technical colleges) & other authors from 1990's using the same (wrong) concept which did NOT use the g factor with mass m (partly to do with SI convention usage (weight dropped, for mass) & partly not). (James) Watt's (work) concept of pounds (=weight) yards, per second is (quite) acceptable. My "Work" (word usage) in the COW thread should be replaced by "wark" (to distinguish it as "moma" (average momentum)); except for "work's energy" which is standard physics "work".

Yes that is what I mean. I am however, because relativistic effects are missing for a high speed example (due to the "opposite" stipulation=condition)). But it's not making sense to have no contraction nor dilation although hi_speed. I doubt that you recognize that (consequence, correctly). We agree there, that's why relativistic effects (contraction & dilation) should exist in "any" (hi_speed case=example) but don't there. "They" don't notice anything (different, caused by the hi_speed, because both differences are the "same"). They (=the ship's capitains) don't notice any time dilation of the other ship, although they should because they are traveling at hi_speed (away). (=Non_preferred ref, e.g. either ship could be used as reference frame. Hi speed, no dilation observed, SR fails!) "Relative to each other."That's what relativity is all about: what the other ship sees (=observes). In that example, they observe no difference (as though SR does not exist) although they are moving at hi_speed relative to each other. That's a paradox, or a flaw! I disagree, in the sense that it will give me a (new) different (unknown) number, which I can "use" to check calculations (for accuracy, or error). It's only a (useful) tool (for me). So it is not telling "you" anything about relativity; (or is it?). I'm not (really) disagreeing with you there.

Thanks. I'm slowly getting the message. Your picture was the most persuasive; & the high speed ball throwing, but reminding me of other limiting math phenomena. (All like Einstein said, but I guess his train was too slow (in my fantasy) for me to accept.) No I meant that it had not made sense to me. I'd say I was being quantative in my evaluation, but I must admit there does seem to be a sarcastic note in it. No distinction (time dilation or contraction) between both space ships each travelling at high speed, but "opposite" directions. If each ship receives the same amount of contraction then compared to each other, they would not observe a difference (between themselves). If both ships dilate the same amount then they will not observe a time difference between them(selves). Each shows no difference from the other although going at high speed wrt to another. In other words both the space ships do not notice relativistic effects although there is a relativistic (hi) speed difference between them. I personally don't expect SR to tell the truth; but standardwise relativistic effects would be expected for 2 objects with a very high speed difference between them. I did not say which space ship exerted thrust, & that is not important according to Einstein's non_prefered referencing. I tend to agree. They won't see c departure, they would see less than c. Relative to each other hi_speed relativitic effects (dilation & contraction) should happen but don't (although moving in opposite directions). That's nice to hear. I still question that because I'm only asking for the difference (a(n unknown) number value) between light speed c & an earth speed v. I haven't changed anything (e.g. c is a constant, & no complicated transforms) & can always find the original speed v (=c-v').

You've said it's wrong but don't say where; I've defined it as a substitution & given the math (algebra); & then Strange "guesses" it's wrong. What else do you want? He's playing games not me. I.e. Is substituting wrong? y/n Is that substitution wrong? y/n What is wrong? e.g. in the algebra. If c=1 dollar, =$1 v=1 cent, then what is the unknown v'=?. Answer: 99 cents. c=v+v'. I could just as easily say c=v+? where the symbol "?" is a value we are searching for. Are you trying to tell me that substitution is wrong? Especially, for (checking) speed.

although they leave each other at light speed c, ((also) meaning wrt each other).I can't tell you how much sense that (now) makes to me. Which space ship has the slower clock (wrt the other)? (Answer: the other (space ship). Which space ship is the other? Answer: both! What does that tell me? Answer: nothing!) Yes I did but I doubt that you recognize the task('s significance) correctly.Einstein's "math" does not allow (adding speeds to be) a speed larger than c, but as you might notice it does NOT agree with the task (observation). Perhaps you would like to pinpoint an error? (If you don't like using departure speed c, (to keep the math simple); then something like 0.999998*c, (e.g. 2 millionths less than c) (for dramatic results) could be used instead, to avoid divide by zero. But simply (2 space ships departing at) 0.98*c (wrt each other; or -0.49*c & 0.49*c wrt earth), gives 0.79*c. (E.g. similar (problematic) results.)

It's a definition. E.g. a substitution. Why then wrong? If it's wrong can you equate my equation to show the error so I can see?

Common sense.

Please explain.(c^2)=((vx+vx')^2)+((vy+vy')^2)+((vz+vz')^2).

& If (v)^2=((vx)^2) + ((vy)^2) + ((vz)^2) & (v')^2=((vx')^2) + ((vy')^2) + ((vz')^2), then why is c not v+v'?

I wanted to know how you would solve the questions & you gave answers, So before presenting anything (socalled new) I would like to consider them. But I have more questions which will help me orientate. E.g. We know we can derive rest mass m' from energy E=m'*c^2). Can we do the same using momentum? (E.g. mom=2*m'*c. ?) I suspect, due to the incompatibility, (between mom & E) you will say no, & modify either the mass &/or momentum (with transforms). My next question would then be, why does (simple) energy receive priorty over (simple) momentum (mom=m*v) in relativity equations? (If momentum is derived from energy & not in reverse.) Why is the priority not reversed (or reversable) so that momentum dominates (the simplicity) & energy needs the transforms (instead)? (Einstein's relativity seems (to me) to prefer energy (evaluation) (being simple), over momentum.) & What is wrong with the syntax of letting c=v+v' where v' symbolizes the compliment (or missing speed (difference)) needed to add with v to give c. (I.e. Having nothing to do with (Lorentz) transforms.) Nothing complicated.

http://hyperphysics.phy-astr.gsu.edu/hbase/Relativ/tdil.html#c4 See: Problems with variable mass. There are "problems with mass" m. Einstein said it is "not good" to use "relativistic mass".. (If it is not good, then it must be bad.) Is the cloth (of Swansont's physics) so whole? Einstein does NOT support (all) his own stuff. Is there a reason for that (lack of support)? He (=Einstein) did NOT say "difficulty (with mass)"; he said "problems" (!, i.e. plural) instead. Was he (=Einstein) hinting also at the problem we now call "dark(=unknown) matter"? (That's) Something just as difficult, with no (satisfactory) explaination. I.e. (The) nonsense does not fit (together so well). [instead Einstein recommended using rest mass, prefering momentum & energy for moving bodies.] I can accept rest mass, & momentum; but I can NOT accept energy E (conservation) because we have "dark (=unknown) energy", too. But I can accept 2*m*E, instead.

Einstein said, there is no preferred reference frame; so why do you reject that 1 in (preferred, biased) favour of the others? Einstein knew SR did NOT work for everything, that is why he invented GR. What is OP=?

Wrt earth each spaceship travels at c/2. What is the answer?

2 space ships leave each other at light speed c. What are their length contractions & time dilations? (E.g. wrt to earth, each is travelling c/2.)

(=I don't see your continuum; it's an interuption instead. =That's a break in physics, no longer the same topic, (a quantum leap if you will, e.g. (absurd like) a lepton.) ("You can't apply standard physics (to the problem when you are trying to assess if you are trying to see if new physics applies.)" =If you can not apply physics, then it (=the so_called "new" physics) is NOT physics (at all). Science confirms (=experimentally reproduceable, independently; (there is more than 1 way to skin a cat; many roads lead to Rome.) I doubt your method of elimination is done correctly.) I'm an interpreter, instead; I remodel. You oppose "my (so_called) new" physics; but it is only a remodeling seeing things from a different perspective (using common sense physics). You then say I make little sense when trying to make sense of your mess. e.g. trying to make your puzzle pieces fit. If you don't understand what I say, you can tell me what you understand (from me) & then ask (what you did not (understand), if you want). Obviously I must have left something out, if not in error.

Sorry, I can't follow, I'm too conservative there.You're proposing what I normally do; but I'm not allowed to do it; you are instead.

Yes, the gravitational acceleration is compensated by Newton's centrifugal acceleration, wrt height, depending on radius, & orbit speed. Yes, another fascinating task from you. "In 2011 the group of Radek Wojtak of the Niels Bohr Institute at the University of Copenhagen collected data from 8000 galaxy clusters and found that the light coming from the cluster centers tended to be red-shifted compared to the cluster edges, confirming the energy loss due to gravity.[6]" Cluster center versus back: A question of light source distance: edge's (average), versus center's (front, middle & rear=back mixture). Explaining the back of a cluster with more red shift. (Considering the red shift is proportional to the distance away (from the earth) in this expanding universe, & thus the amount of acceleration duration (time).) Is it not possible, the center (spectral) samples also have "distances" (from earth to light source) beyond the (cluster's) center to the (cluster's) "furthest end" thus (also have) larger distance & (more light) amount (e.g. densest population, = most number of stars) than the edges (e.g. perimeter) which could be seen (=interpretted) as (ruffly=aproximately) the average distance (from earth) to the (cluster's) middle (or center) when viewing the cluster as ruffly a sphere? Those edges do NOT extend (from earth) to the cluster's back "half". The (observed cluster) center would have all sorts of distances to the cluster: front, middle, & "back"; explaining the extra red shift. The extreme edge (away from the center, not front nor back sides) would only be approximately middle (=average) distance, e.g. similar to from earth to the cluster's center. (E.g. Think of the cluster in 2D, as a circle (e.g. flat like an equator) with a near & far end wrt the earth.)

I agree. I don't see, how you can have an electric field in a hollow conductor because the (volume) charge density of the metal should be (significantly) the same overall. That means NO potential difference in the volume within (=inside). If however we consider the conductor has a DC resistance then it may be possible to consider a (very) slight voltage drop between the source's 2 poles (or plates) far(ther) away from the hollow conductor. (I think) here we have a hypothesis expected (to be used) as truth to (try to) disprove a photon's mass. That is absurd. Why isn't an (known) observed effect used instead, to prove or disprove (photon mass); rather than inventing (an (new) effect that has never been found (at all) to deny a(n existing) calculated mass. That's not spectacular, that's a scandal. I.e. 1st propose (=predict) something that does NOT exist; & then use that assumption to disclaim a(n existing) (photon's) mass. I call that false prophecy. Or have I missed something?

If you measure (a freely) fall(ing object) in a vacuum (=no air resistance) you will measure acceleration, whether light or an object is falling. Thus I can't follow your argumentation. (Maybe you mean weightlessness?) How do you explain coax (TV) cable?The outer sheath (conductor) would be your hollow conductor mentioned. Theoretically, no electric field should be possible within that (sheath conductor). Or do you mean something else? I'm still not clear how you are "measuring" there (so far away).(=I'm a bit foggy.) Could you clarify, a bit? Thanks Sensei (for the links), but I meant: what other things are possible? A particle can be accelerated or decelerated, but what else can happen? (=your "etc", what other examples?).

I think your problem (there) is you don't want to admit gravity's free fall g=-9.8 m/(s^2) is an acceleration (when you say that); light falls (like any other moving object, (ruffly) without air resistance); sound does NOT. That means light accelerates. Please explain a bit (those experiments, so I can grasp what's happening). Spectacular sounds interesting.

Don't you surely mean 8.5*(10^(-28)) kg*m/s, instead? (Negative exponent -28, instead of positive 28.) (1.56 eV=2.55*(10^(-19)) J. mom~2*E/v.) The photon is moving at c light's speed.The photon's mass is (the momentum divided by it's speed v=c) m=mom/v=8.5*(10^(-28)) [kg*m/s]/(2.99*(10^8)) m/s)=2.85*(10^(-36)) kg.

I don't use the Lorentz transform in momentum because (it's redundant, when) I set the limit speed to c=v+v'. Similar can be done with KE (but energy gives wrong answers, m*E should be used instead). The Galilean transform was never invented with a speed limit (e.g. c) because they thought light's speed was infinite. We know better, now & can change that.