According to 1905 Relativity, a single material point must be always at rest
in [Relativity]
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From: glird on 21 May 2010 17:27 On May 21, 4:00 pm, Darwin123 <drosen0...(a)yahoo.com> wrote: > Denial. It is not just a river |:-) Contrary to what someone wrote in this thread, a "frame of reference" DOES have one visible object as referent. THAT object is always at rest wrt the frame of reference permanently attached to it. So is any co-ordinate system (a set of three imaginary lines perpendicular to each other and intersecting at a point) whose origin (the imaginary point where its three lines, called "dimensions", intersect) is permanently attched to that object. Even if the object is physically rotating in space, its frame of reference remains at rest wrt to it. If some OTHER object is moving at v wrt a given such frame of reference, then so is anything in a frame of reference attached to THAT object. In the passage someone quoted above, Einstein assumed that a clock that moved at v in a series of differently directed lines in a frame attached to Earth, could be considered as equivalent to one that moved "in a closed curve with constant velocity". Although he should have said "with constant speed", so what? In his next sentence he said "a balance-clock * at the equator must go more slowly ..." and in the asterisked footnote excluded a pendulum clock because it is NOT at rest in Earth's frame of reference. His point was that the rate of events in one frame of reference is different than the rate of identical events in a system moving at v wrt to that one. In any event,in Newton's laws he thought that all atoms were identical (had the same weight and mass as each other) thus that the actions of large objects in response to a given applied force would be "proportional" (NOT "equal"!) to their masses. Unfortunately, physics mis-stated his 3rd law and have never correctly understood Einstein's equations. THAT - plus loose semantics in all directions - is why threads like this go on and on almost endlessly. glird
From: PD on 21 May 2010 17:42 On May 21, 4:27 pm, glird <gl...(a)aol.com> wrote: > On May 21, 4:00 pm, Darwin123 <drosen0...(a)yahoo.com> wrote: > > > Denial. It is not just a river |:-) > > Contrary to what someone wrote in this thread, a "frame of reference" > DOES have one visible object as referent. That simply is flat wrong. It is always possible to attach a reference frame to any visible object so that the object is at rest in the frame. This does not imply that you have to hunt around for a visible object to attach the frame to, in order to specify the frame. > THAT object is always at > rest wrt the frame of reference permanently attached to it. So is any > co-ordinate system (a set of three imaginary lines perpendicular to > each other and intersecting at a point) whose origin (the imaginary > point where its three lines, called "dimensions", intersect) is > permanently attched to that object. > Even if the object is physically rotating in space, its frame of > reference remains at rest wrt to it. If some OTHER object is moving at > v wrt a given such frame of reference, then so is anything in a frame > of reference attached to THAT object. > In the passage someone quoted above, Einstein assumed that a clock > that moved at v in a series of differently directed lines in a frame > attached to Earth, could be considered as equivalent to one that moved > "in a closed curve with constant velocity". Although he should have > said "with constant speed", so what? In his next sentence he said "a > balance-clock * at the equator must go more slowly ..." and in the > asterisked footnote excluded a pendulum clock because it is NOT at > rest in Earth's frame of reference. > His point was that the rate of events in one frame of reference is > different than the rate of identical events in a system moving at v > wrt to that one. > In any event,in Newton's laws he thought that all atoms were > identical (had the same weight and mass as each other) thus that the > actions of large objects in response to a given applied force would be > "proportional" (NOT "equal"!) to their masses. > Unfortunately, physics mis-stated his 3rd law and have never > correctly understood Einstein's equations. THAT - plus loose semantics > in all directions - is why threads like this go on and on almost > endlessly. > > glird
From: Dono. on 21 May 2010 17:44 On May 21, 2:27 pm, glird <gl...(a)aol.com> wrote: > > Unfortunately, physics mis-stated his 3rd law and have never > correctly understood Einstein's equations. THAT - plus loose semantics > in all directions - is why threads like this go on and on almost > endlessly. > Nah, it is imbeciles like you , Lebau, who never progressed past the inability to understand the very basics of SR.
From: blackhead on 21 May 2010 21:02 On 21 May, 12:01, va...(a)icmf.inf.cu wrote: > On 20 mayo, 21:42, "Inertial" <relativ...(a)rest.com> wrote:> <va...(a)icmf.inf.cu> wrote in message > > >news:c13b9123-0513-4072-8dc5-54557b8cfaf5(a)y12g2000vbr.googlegroups.com... > > > > In his first Relativity paper (30June1905), after declaring the ether > > > superfluous, Einstein considers a material point at rest. He uses a > > > system of Cartesian coordinates in which the equations of Newtonian > > > mechanics and Euclidean geometry hold good. If the massive body is > > > alone (and then without a Newtonian gravitational force acting on it), > > > it must remains forever at rest in its own centre of mass inertial > > > frame. > > > RVHG (Rafael Valls Hidalgo-Gato) > > > Yeup .. do you think that is a problem? > > Not for me, but maybe for other persons. > In the Newtonian view (with absolute space and time), a single > material point can have any constant velocity v in an infinite > quantity of different inertial frames. > In the 1905 Einsteinian view (without absolute space and time), the > same single material point can have only the constant velocity v=0 in > a unique inertial frame. > Are we in agreement about that? You've forgotten that inertial frames can be rotated wrt with one another with v = 0 for the material point. > RVHG (Rafael Valls Hidalgo-Gato)
From: Androcles on 21 May 2010 21:19
"blackhead" <larryharson(a)softhome.net> wrote in message news:f6138a42-e150-411c-9bed-3f510209de99(a)e21g2000vbl.googlegroups.com... | On 21 May, 12:01, va...(a)icmf.inf.cu wrote: | > On 20 mayo, 21:42, "Inertial" <relativ...(a)rest.com> wrote:> <va...(a)icmf.inf.cu> wrote in message | > | > >news:c13b9123-0513-4072-8dc5-54557b8cfaf5(a)y12g2000vbr.googlegroups.com... | > | > > > In his first Relativity paper (30June1905), after declaring the ether | > > > superfluous, Einstein considers a material point at rest. He uses a | > > > system of Cartesian coordinates in which the equations of Newtonian | > > > mechanics and Euclidean geometry hold good. If the massive body is | > > > alone (and then without a Newtonian gravitational force acting on it), | > > > it must remains forever at rest in its own centre of mass inertial | > > > frame. | > > > RVHG (Rafael Valls Hidalgo-Gato) | > | > > Yeup .. do you think that is a problem? | > | > Not for me, but maybe for other persons. | > In the Newtonian view (with absolute space and time), a single | > material point can have any constant velocity v in an infinite | > quantity of different inertial frames. | | > In the 1905 Einsteinian view (without absolute space and time), the | > same single material point can have only the constant velocity v=0 in | > a unique inertial frame. | > Are we in agreement about that? | | You've forgotten that inertial frames can be rotated wrt with one | another with v = 0 for the material point. | You've forgotten (or more likely never knew) that Einstein didn't have anything to do with Newton's inertial frames and are irrelevant to SR. "If we assume that the result proved for a polygonal line is also valid for a continuously curved line, we arrive at this result: If one of two synchronous clocks at A is moved in a closed curve with constant velocity until it returns to A, the journey lasting t seconds, then by the clock which has remained at rest the travelled clock on its arrival at A will be second slow. Thence we conclude that a balance-clock at the equator must go more slowly, by a very small amount, than a precisely similar clock situated at one of the poles under otherwise identical conditions." -- Albert Fuckwit Einstein |