0 Members and 1 Guest are viewing this topic.
Quote from: lean bean on 14/11/2012 22:05:46No force required. Your constant referring to a force is a reflection of your misunderstanding of time dilation and length contraction.You can also demonstrate that forces can, in fact, be thought of as reshaping things at high speeds. The force holding the probe (in the famous probe example) together are electromagnetic and communicated at light speed. Since electromagnetism travels a the speed of light, and the speed of light is constant as the observer moves, these bonds change length and that changes the length of the probe as it moves. You can interpret this different ways, but it's pretty obvious that it can certainly be interpreted as the electromagnetic force leading to a reshaping of the probe as you fly by it at high speeds.
No force required. Your constant referring to a force is a reflection of your misunderstanding of time dilation and length contraction.
The bay IS 10 meters long. The probe IS 20 meters long. All "appearences" aside, the probe will not fit in the bay, and it will not "actually" change lengths. All "appearences" aside, Earth's diameter IS and stays nearly 8000 miles regardless of how it might "appear" to a fast moving traveler. And the probe IS and stays 20 meters long regardless of how it appears from Earth. Do both of you (zordim and D.C.) understand this? How about you, JP.
What you're saying can be true with the Spacetime of SR, but if you reject Spacetime you're going to have to have actual, real, genuine, absolute length contraction of moving things. Without it, your theory conflicts with Michelson Morley.
The Michelson Morley experiment disagrees with you. Things are length contracted in their direction of travel.
The key words are "appear" vs "actually." Earth's diameter does not actually shrink to accomodate how the probe sees it, nor does the probe's length actually shrink to accomodate how Earth sees it in this .866c relative velocity scenario, which works both ways.
The key words are "appear" vs "actually." Earth's diameter does not actually shrink to accomodate how the probe sees it, nor does the probe's length actually shrink to accomodate how Earth sees it in this .866c relative velocity scenario, which works both ways.If the principle of length contraction were true, the probe would actually shrink to 10 meters when measured from Earth, approaching at .866c. But it only appeared to be 10 meters. The same holds in reverse for Earth as seen from the probe. To be consistent about length contraction, Earth would actually shrink in diameter to 4000 miles. That is blatant nonsense.
The same holds for the MM experiment, which you keep repeating as proof of length contraction. The arm in the direction of travel appears to shrink as distinct from actually shrinks as in the examples above... and in the example of the distance to the Sun, which might appear to shrink as seen from a fast fly-by frame.
You insist on "length contraction of moving things." Do you get that everything is moving, so velocity must specify "relative to what?"
So Earth is moving at .866c relative to the probe as well as vice-versa. Do you or do you not think that its diameter actually contracts to 4000 miles in that case? A direct answer would be refreshing. I can not get one one from JP, and zordim seems to be living in a universe of his own creation.
We have been over this many times.
SR theorists claim that from a frame of reference flying by Earth at near light speed ('c') Earth's diameter as measured in the direction of the fly-by would be contracted, making Earth a very oblate spheroid rather than the near sphere established by Earth science. Further, they claim that the effect is not just a distortion (appearance only) but that Earth is in fact flattened (like the subatomic particles) "for that frame of reference" and that "there is no preferred frame of reference," so that measurement (flattened shape of earth) is "equally valid."What say you SR experts here?
From the rest frame of the ship it is completely valid. From the lab on earth we can predict with accuracy what the ship would observe and it matches what the ship's crew do observe.
D.C.,I am not interested in your take on other theories as I've said several times before. I am challengeing the length contraction part of SR theory, as my OP clearly stated. I am also not interested in using "spacetime" as a way to explain that length contraction is image distortion or explained by difference in appearence, though that is my argument, sans "spacetime."
Imatfaal, a mod representing this forum as an expert on length contraction, answered my challenge... "so that measurement (flattened shape of earth) is "equally valid""... saying, "it is completely valid."
You continue to try to hijack this thread to promote your agenda about other competitive theories. Again, not interested.
I continue to be interested in getting an honest reply... from those here who speak for SR's version of length contraction... to the challenge of the length contracted Earth and distance to the sun. My probe & shuttle was a smaller scale example of the same principle they promote regarding those examples.
D.C.:"If you reject Spacetime, you clearly must be interested in other theories,..."Don't tell me what I'm interested in! See bolded "not interested" comments in last post.
I am interested in debunking large scale (not subatomic) length contraction, ...
... and the reification of "spacetime" into a supposed entity which is curved by mass. If it were just a coordinate system/model (fine with me) GR theory would not insist that it is *something* which mass curves or that it is *something* which guides masses in their curved paths.
The same argument against an actually contracted Earth diameter and contracted distances between cosmic bodies holds for a contracted arm of a physical structure like the MM experimental apparatus (or a theoretical "alien probe.")
Since you think otherwise, show me the difference, i.e., how the arm actually contracts but Earth's diameter (etc.) does not, as they all depend on the same theory and principle, i.e., that physical objects and actual distances change with how they are observed.
Hi, I'm a believer in SR but not GR. I believe that length contractions are apparent and not actual - they merely show up as length contractions when you convert a 4D object into 3D space. I have a beef to pick with people who believe in SR but who think that objects change their actual shape as you view them from different frames of reference.O.G.
Hi O.G.,Nice to hear your point of view. Food for thought.
Hi,I'm a believer in SR but not GR. I believe that length contractions are apparent and not actual - they merely show up as length contractions when you convert a 4D object into 3D space. I have a beef to pick with people who believe in SR but who think that objects change their actual shape as you view them from different frames of reference.O.G.
D.C.:" Well, if you aren't actually interested in OGVT, stop telling us it's right.""OGVT" is your acronym. My "search" in this forum failed to find your first reference, spelling it out. Google just gave "OutGoing Verification Trunk." (?)
Me:" I am interested in debunking large scale (not subatomic) length contraction," ...You:"Which means that Either you want to junk OGVT in favour of something like LET, or you adopt something like SR."Huh? It means that the constant speed of light as per SR, which is well documented, does not automatically require that physical objects actually contract in length.
As said in my other (locked) length contraction thread, the "warning" on convex mirrors is applicable to the concept of length contraction. "Warning: Objects may appear closer than they are!" The LC version would be: "Warning: Objects approaching at very high velocity may appear shorter than they are!"
As I understand your usage of "LET" the Lorentz "camp" says that physical objects do physically contract. I say that would require force to crush the object or compact the distance between the atoms of such objects.
SR claims that all frames are equally valid and that length is not invariant. Realism, my take, disagrees. Physical objects have inherent, intrinsic properties, including length, which do not change with the various frames from which they are observed. This repeats what I have said many times, because you still show no sign of understanding my argument.
You:"GR is the best reason for taking SR seriously, so I don't know why you'd want to ditch that."I accept that the math/model of GR improves upon Newtonian prediction of the effects of gravity. I deny that this requires insistence that "mass curves spacetime" (curves what?) and that the resulting "curved spacetime" guides masses in their curved paths. (Again, repeated many times... all lost on you.)
I wanted you to answer directly, truthfully, as you understand the answer.If length contraction is "apparent and not actual" (as I see it), then the "contracted" arm of the MM apparatus is "apparent, not actual." Yet you constantly cite it as proof of actual length contraction.
Btw and finally, I find your mock post of my position, signed "O.G." very offensive, as follows:QuoteHi,I'm a believer in SR but not GR. I believe that length contractions are apparent and not actual - they merely show up as length contractions when you convert a 4D object into 3D space. I have a beef to pick with people who believe in SR but who think that objects change their actual shape as you view them from different frames of reference.O.G.I have explained many times which parts of both SR and GR I reject, and which parts I accept. No such thing as a "4D object." All space and objects in it (not just lines and planes) are 3D (length, width & height) and as 3D objects move through space, "time elapses."
I wanted you to answer directly, truthfully, as you understand the answer. If length contraction is "apparent and not actual" (as I see it), then the "contracted" arm of the MM apparatus is "apparent, not actual." Yet you constantly cite it as proof of actual length contraction.
Don't get the theories mixed up. MM requires actual length contraction in an OGVT/LET type of theory. The alternative is that it requires you to use a 4D Spacetime model. If you have always accepted 4D Spacetime, then OGVT is the wrong name for what I thought was your theory of realism - I thought at that time that you rejected Spacetime, but now you're maybe happy to have it so long as you deny that it has any fabric to it.
Hi, I'm a believer in SR but not GR. I believe that length contractions are apparent and not actual - they merely show up as length contractions when you convert a 4D object into 3D space. I have a beef to pick with people who believe in SR but who think that objects change their actual shape as you view them from different frames of reference. O.G.
My intention was not to mock you in any way - I'm trying to help you state your position clearly so that it's possible for people to work out what you're on about.