Who's familiar with the conversion? - "In 15 years' ship-time they could reach Andromeda

A theory is correct if and only if it can make predictions that are confirmed by experiment that no other theory can make.

Underdetermination is a thesis explaining that for any scientifically based theory there will always be at least one rival theory that is also supported by the evidence given, and that that theory can also be logically maintained in the face of any new evidence.

Who knew? If you had understood anything about the "test theory" material I quoted for you, Max, you would understand that special relativity is, at best, "underdetermined."

God! I don't know why I came back to this train wreck of a thread.

You can read about the results here

What is now often called Lorentz ether theory (LET) has its roots in Hendrik Lorentz's "theory of electrons", which was the final point in the development of the classical aether theories at the end of the 19th and at the beginning of the 20th century.... it is not possible to distinguish between LET and SR by experiment.

Mansouri and Sexl spoke about the "remarkable result that a theory maintaining absolute simultaneity is equivalent to special relativity." They also noticed the similarity between this test theory and Lorentz ether theory of Hendrik Lorentz, Joseph Larmor and Henri Poincare.

Different test theories differ in their assumptions about what form the transform equations could reasonably take. There are at present four test theories of SR:

•Robertson, Rev. of Mod. Phys. 21, pg 378 (1949).
•Edwards, Am. J. Phys. 31 (1963), pg 482.
•Mansouri and Sexl, Gen. Rel. Grav. 8 (1977), pg 497, pg 515, pg 809.
•Zhang, Special Relativity and its Experimental Foundations.

These test theories can also be used to examine potential alternative theories to SR...The existing experiments put rather strong experimental constraints on any alternative theory.

...many different theories, characterized by different values of such parameters, are equivalent to SR in that they are experimentally indistinguishable from SR (though they differ from SR in other aspects).

Today LET is often treated as some sort of "Lorentzian" or "neo-Lorentzian" interpretation of special relativity. The introduction of length contraction and time dilation for all phenomena in a "preferred" frame of reference, which plays the role of Lorentz's immobile aether, leads to the complete Lorentz transformation (see the Robertson–Mansouri–Sexl test theory as an example). Because the same mathematical formalism occurs in both, it is not possible to distinguish between LET and SR by experiment. However, in LET the existence of an undetectable aether is assumed and the validity of the relativity principle seems to be only coincidental, which is one reason why SR is commonly preferred over LET.

Data Does Not Match Special Relativity Time Dilation

Prior to Special Relativity, Lorentz developed Lorentz Relativity. The equations of Lorentz Relativity look identical to Special Relativity, but they have a very different physical meaning.

All users of Lorentz Relativity have the same consistent view of what's happening physically. Furthermore, there are no paradoxes or apparent contradictions. Lorentz Relativity gives a single, coherent physical description of space and time.

In Special Relativity, if clock A is measured, by A , as one half as fast as clock B, then clock B is also measured, by B, as one half as fast as clock A. Hence, we can see that Special Relativity is not describing what's happening physically. Special Relativity is an observer-centric theory - it gives each observer his own idiosyncratic view of spacetime and all these different observer views are in conflict with one another.

While Special Relativity will, in its domain, correctly predict final outcomes, its (implied) description of the physics is not correct...Special Relativity simulates the correct physical model, namely, Lorentz Relativity, and because of other factors such as the constraints of the conservation laws and certain unique math properties of the Lorentz factor, Special Relativity is able to predict the outcome of certain events - however, the Special Relativity math tends to be misleading about the details of what's happening physically.

In GPS, the data clearly shows that the Special Relativity model does NOT correctly describe what’s happening physically and specifically it cannot be used and is not used in GPS. An equation is used that looks like Special Relativity's time dilation equation, but it's used in a way that is inconsistent with Special Relativity and instead consistent with Lorentz Relativity. Because the equation that is used looks like Special Relativity's time dilation equation, some still erroneously claim that Special Relativity is used...GPS uses the Lorentz physical model which is the antithesis of Special Relativity. The confusion is aided by the two theories using equations where the math looks identical. Both theories are based on the Lorentz Transformation (LTs) equations, but the two theories interpret those equations completely differently

Anyway... I am going away again.

Suppose this dragster is participating in a 20 mile race down a straight track with a big crowd lining the whole route.

The dragster has a top end of 200 mph. As long as he has enough gas, he can maintain that speed, but he can't exceed it, get the idea? After he hits top end he just "cruises" along at 200 mph.

Would he now (while cruising) be correct, if he claims he's not moving wrt the crowd (the earth's surface)?

Getting any kinda feel for "underdetermination" now, at all?

Willing to concede that BY YOUR DEFINITON Special Relativity is not "correct?"

http://www.nature.com/news/the-quantum-source-of-space-time-1.18797

All that’s needed, he asserted, is ‘entanglement’: the phenomenon that many physicists believe to be the ultimate in quantum weirdness. Entanglement lets the measurement of one particle instantaneously determine the state of a partner particle, no matter how far away it may be — even on the other side of the Milky Way.

The big difference between LET and SR is LET posits that there is an aether.

What is now often called Lorentz ether theory (LET)

layman wrote:

What is now often called Lorentz ether theory (LET)