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标题: 用相对论如何解释萨格纳克干涉实验 [打印本页]

作者: llgzcts 时间: 2007-11-12 22:04
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作者: llgzcts 时间: 2007-11-12 22:20
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作者: llgzcts 时间: 2007-11-12 23:36
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作者: benlinliu 时间: 2007-11-13 21:44
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作者: llgzcts 时间: 2007-11-13 21:49
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作者: benlinliu 时间: 2007-11-13 21:59
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作者: llgzcts 时间: 2007-11-13 22:21
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作者: benlinliu 时间: 2007-11-13 22:25
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作者: llgzcts 时间: 2007-11-13 22:30
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作者: 愚石 时间: 2007-11-13 22:37
我来帮你贴一下，因为文字里边有公事，用LATEX麻烦点，就用图片了。

作者: llgzcts 时间: 2007-11-13 22:50
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作者: kxjh 时间: 2007-11-14 09:13
标题: 回复 #11 llgzcts 的帖子
用键盘上的“PrintScreen”键

作者: 愚石 时间: 2007-11-14 12:05

原帖由 kxjh 于 2007-11-14 09:13 发表

 登录/注册后可看大图

用键盘上的“PrintScreen”键

没错，就是用它。
不过，我也不知道页面要是超过了屏幕高度该如何一次拍整页下来。
他这页我是压缩了行距才拍下来。

拍摄方法：
1、打开需要拍的页面，
2、按一下“PrintScreen”键，
3、打开画图（或其它图像处理软件），
4、执行粘贴，
5、裁掉没用的边角
6、另存为PNG 或者其它合适的格式。
7、喝口水、
8、发布。。。。。。。。。。。。。。。。。。。

作者: benlinliu 时间: 2007-11-14 12:25
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作者: llgzcts 时间: 2007-11-14 12:32
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作者: worren 时间: 2007-11-14 12:55
摘选原文中最主要的一个错误：“当实验装置绕中心点旋转的角速度改变时，观测到了干涉条纹的移动。实验结果表明光速与观察者的运动状态有关（观测镜T和反射镜都可以看作是观测者）”

按照这句话的逻辑，光的干涉条纹变化与否，与光速是否变化直接联系到了一起，是绝对的错误。
干涉条纹的移动，只能说明观测者观测到的光的波长（λ)或者频率(γ)发生了变化．在波动光学中的杨氏双缝干涉实验（证明光具有波动性的实验）中，不同频率的光所形成的干涉条纹的间距不同，也说明光频率与干涉条纹的宽窄具有联系．
但是光速(V=λγ=S/T),即速度=波长×频率＝路程/时间，无论波长、频率、路程、时间如何变化，速度V总是常量C。
这萨格纳克干涉实验用了一种偷换概念的手法，只能骗过没有严格掌握物理学概念和定义的人。

[ 本帖最后由 worren 于 2007-11-14 12:59 编辑 ]

作者: worren 时间: 2007-11-14 13:03
如果详细学过波动光学，这个问题一定能自己解决；
问题并非出在实验本身上，而是文章作者对于物理概念与实验现象之间的联系没搞清楚，张冠李戴。

作者: worren 时间: 2007-11-14 13:18
萨格纳克实验效应的物理含义也不应该被歪曲成这副德行；

http://www.mathpages.com/rr/s2-07/2-07.htm
2.7  The Sagnac Effect

Blind unbelief is sure to err,

And scan his work in vain;

God is his own interpreter,

And he will make it plain.

            William Cowper, 1780

If two pulses of light are sent in opposite directions around a stationary circular loop of radius R, they will traveled the same inertial distance at the same speed, so they will arrive at the end point simultaneously. This is illustrated in the left-hand figure below.

The figure on the right indicates what happens if the loop itself is rotating during this procedure. The symbol a denotes the angular displacement of the loop during the time required for the pulses to travel once around the loop. For any positive value of a, the pulse traveling in the same direction as the rotation of the loop must travel a slightly greater distance than the pulse traveling in the opposite direction. As a result, the counter-rotating pulse arrives at the "end" point slightly earlier than the co-rotating pulse. Quantitatively, if we let w denote the angular speed of the loop, then the circumferential tangent speed of the end point is v = wR, and the sum of the speeds of the wave front and the receiver at the "end" point is c-v in the co-rotating direction and c+v in the counter-rotating direction. Both pulses begin with an initial separation of 2pR from the end point, so the difference between the travel times is

where A = pR2 is the area enclosed by the loop. This analysis is perfectly valid in both the classical and the relativistic contexts. Of course, the result represents the time difference with respect to the axis-centered inertial frame. A clock attached to the perimeter of the ring would, according to special relativity, record a lesser time, by the factor g = (1-(v/c)2)1/2, so the Sagnac delay with respect to such a clock would be [4Aw/c2]/(1-(v/c)2)1/2. However, the characteristic frequency of a given light source co-moving with this clock would be greater, compared to its reduced value in terms of the axis-centered frame, by precisely the same factor, so the actual phase difference of the beams arriving at the receiver is invariant. (It's also worth noting that there is no Doppler shift involved in a Sagnac device, because each successive wave crest in a given direction travels the same distance from transmitter to receiver, and clocks at those points show the same lapse of proper time, both classically and in the context of special relativity.)

This phenomenon applies to any closed loop, not necessarily circular. For example, suppose a beam of light is split by a half-silvered mirror into two beams, and those beams are directed in a square path around a set of mirrors in opposite directions as shown below.

Just as in the case of the circular loop, if the apparatus is unaccelerated, the two beams will travel equal distances around the loop, and arrive at the detector simultaneously and in phase. However, if the entire device (including source and detector) is rotating, the beam traveling around the loop in the direction of rotation will have farther to go than the beam traveling counter to the direction of rotation, because during the period of travel the mirrors and detector will all move (slightly) toward the counter-rotating beam and away from the co-rotating beam. Consequently the beams will reach the detector at slightly different times, and slightly out of phase, producing optical interference "fringes" that can be observed and measured.

Michelson had proposed constructing such a device in 1904, but did not pursue it at the time, since he realized it would show only the absolute rotation of the device. The effect was first demonstrated in 1911 by Harress (unwittingly) and in 1913 by Georges Sagnac, who published two brief notes in the Comptes Rendus describing his apparatus and summarizing the results. He wrote

The result of measurements shows that, in ambient space, the light is propagated with a speed V0, independent of the overall movement of the source of light O and optical system.

This rules out the ballistic theory of light propagation (as advocated by Ritz in 1909), according to which the speed of light is the vector sum of the velocity of the source plus a vector of magnitude c. Ironically, the original Michelson-Morley experiment was consistent with the ballistic theory, but inconsistent with the naïve ether theory, whereas the Sagnac effect is consistent with the naïve ether theory but inconsistent with the ballistic theory. Of course, both results are consistent with fully relativistic theories of Lorentz and Einstein, since according to both theories light is propagated at a speed independent of the state of motion of the source.

Because of the incredible precision of interferometric techniques, devices like this are capable of detecting and measuring extremely small amounts of absolute rotation. One of the first applications of this phenomenon was an experiment performed by Michelson and Gale in 1925 to measure the absolute rotation rate of the Earth by means of a rectangular optical loop 2/5 mile long and 1/5 mile wide. (See below for Michelson’s comments on this experiment.) More recently, the invention of lasers around 1963 has led to practical small-scale devices for measuring rotation by exploiting the Sagnac effect. There are two classes of such devices, namely, ring interometers and ring lasers. A ring interferometer typically consists of many windings of fiber optic lines, conducting light (of a fixed frequency) in opposite directions around a loop, and then recombining them to measure the phase difference, just as in the original Sagnac apparatus, but with greater efficiency and sensitivity. A ring laser, on the other hand, consists of a laser cavity in the shape of a ring, which allows light to circulate in both directions, producing two standing waves with the same number of nodes in each direction. Since the optical path lengths in the two directions are different, the resonant frequencies of the two standing waves are also different. (In practice it is typically necessary to “dither” the ring to prevent phase locking of the two modes.) The “beat” between the two frequencies is measured, giving a result proportional to the rotation rate of the device. Incidentally, it isn’t necessary for the actual laser cavity to circumscribe the entire loop; longitudinal pumping can be used, driven by feedback carried in opposite directions around the loop in ordinary optical fibers. (Needless to say, the difference in resonant frequency of the two stand waves in a ring laser due to the different optical path lengths is not to be confused with a Doppler shift.) Today such devices are routinely used in guidance and navigation systems for commercial airliners, nautical ships, spacecraft, and in many other applications, and are capable of detecting rotation rates as slight as 0.00001 degree per hour.

We saw previously that the time delay (and therefore the difference in the optical path lengths) for a circular loop is proportional to the area enclosed by the loop. This interesting fact actually applies to arbitrary closed loops. To prove this, we will derive the difference in arrival times of the two pulses of light for an arbitrary polygonal loop inscribed in a circle. Let the (inertial) coordinates of two consecutive mirrors separated by a subtended angle q be

where w is the angular velocity of the device. Since light rays travel along null intervals, we have  c2(dt)2 = (dx)2 + (dy)2,  so the coordinate time T required for a light pulse to travel from one mirror to the next in the forward and reverse directions satisfies the equations

Typically wT is extremely small, i.e., the polygon doesn't rotate through a very large angle in the time it takes light to go from one mirror to the next, so we can expand these equations in wT (up to second order) and collect powers of T to give the quadratic

The two roots of this polynomial are the values of T, one positive and one negative, for the co-rotating and counter-rotating solutions, so the difference in the absolute times is the sum of these roots. Hence we have

This is the net contribution of this edge to the total time increment. Recalling that the area of a regular n-sided polygon of radius R is nR2sin(2p/n)/2, the area of the triangle formed by the hub and the two mirrors is R2sin(q)/2. It follows that each edge of an arbitrary polygonal loop inscribed in a circle contributes 4Aiw/(c2 - v2cos(q)) to the total time discrepancy, where Ai is the area of the ith triangular slice of the loop and v = Rw is the tangential speed of the mirrors. Therefore, the total discrepancy in travel times for the co-rotating and counter-rotating beams around the entire loop is simply

where A is the total area enclosed in the loop. This applies to polygons with any number of sides, including the limiting case of circular fiber-optic loops with virtually infinitely many edges (where the "mirrors" are simply the inner reflective lining of the fiber-optic cable), in which case q goes to zero and the denominator of the phase difference is simply c2 - v2. For realistic values of v (i.e., very small compared with c), the phase difference reduces to the well-known result  4Aw/c2. It's worth noting that nothing in this derivation is unique to special relativity, because the Sagnac effect is a purely "classical" effect. The apparatus is set up as a differential device, so the relativistic effects apply equally in both directions, and hence the higher-order corrections of special relativity cancel out of the phase difference.

Despite the ease and clarity with which special relativity accounts for the Sagnac effect, one occasionally sees claims that this effect entails a conflict with the principles of special relativity. The usual claim is that the Sagnac effect somehow falsifies the invariance of light speed with respect to all inertial coordinate systems. Of course, it does no such thing, as is obvious from the fact that the simple description of an arbitrary Sagnac device given above is based on isotropic light speed with respect to one particular system of inertial coordinates, and all other inertial coordinate systems are related to this one by Lorentz transformations, which are defined as the transformations that preserve light speed. Hence no description of a Sagnac device in terms of any system of inertial coordinates can possibly entail non-isotropic light speed, nor can any such description yield physically observable results different from those derived above (which are known to agree with experiment).

Nevertheless, it remains a seminal tenet of anti-relativityism (for lack of a better term) that the trivial Sagnac effect somehow "disproves relativity". Those who espouse this view sometimes claim that the expressions "c+v" and "c-v" appearing in the derivation of the phase shift are prima facie proof that the speed of light is not c with respect to some inertial coordinate system. When it is pointed out that those quantities do not refer to the speed of light, but rather to the sum and difference of the speed of light and the speed of some other object, both with respect to a single inertial coordinate system, which can be as great as 2c according to special relativity, the anti-relativityists are undaunted, and merely proceed to construct progressively more convoluted and specious "objections". For example, they sometimes argue that each point on the perimeter of a rotating circular Sagnac device is always instantaneously at rest in some inertial coordinate system, and according to special relativity the speed of light is precisely c in all directions with respect to any inertial system of coordinates, so (they argue) the speed of light must be isotropic at every point around the entire circumference of the loop, and hence the light pulses must take an equal amount of time to traverse the loop in either direction. Needless to say, this "reasoning" is invalid, because the pulses of light are never (let alone always) at the same point in the loop at the same time during their respective trips around the loop in opposite directions. At any given instant the point of the loop where one pulse is located is necessarily accelerating with respect to the instantaneous inertial rest frame of the point on the loop where the other pulse is located (and vice versa). As noted above, it’s self-evident that since the speed of light is isotropic with respect to at least one particular frame of reference, and since every other frame is related to that frame by a transformation that explicitly preserves light speed, no inconsistency with the invariance of the speed of light can arise.

Having accepted that the observable effects predicted by special relativity for a Sagnac device are correct and entail no logical inconsistency, the dedicated opponents of special relativity sometimes resort to claims that there is nevertheless an inconsistency in the relativistic interpretation of what's really happening locally around the device in certain extreme circumstances. The fundamental fallacy underlying such claims is the idea that the beams of light are traveling the same, or at least congruent, inertial paths through space and time as they proceed from the source to the detector.  If this were true, their inertial speeds would indeed need to differ in order for their arrival times at the detector to differ. However, the two pulses do not traverse congruent paths from emission to detector (assuming the device is absolutely rotating). The co-rotating beam is traveling slightly farther than the counter-rotating beam in the inertial sense, because the detector is moving away from the former and toward the latter while they are in transit. Naturally the ratio of optical path lengths is the same with respect to any fixed system of inertial coordinates.

It’s also obvious that the absolute difference in optical path lengths cannot be "transformed away", e.g., by analyzing the process with respect to coordinates rigidly attached to and rotating along with the device. We can, of course, define a system of coordinates in terms of which the position of a point  fixed on the disk is independent of the time coordinate, but such coordinates are necessarily rotating (accelerating), and special relativity does not entail invariant or isotropic light speed with respect to non-inertial coordinates. (In fact, one need only consider the distant stars circumnavigating the entire galaxy every 24 hours with respect to the Earth's rotating system of reference to realize that the limiting speed of travel is generally not invariant and isotropic in terms of accelerating coordinates.) A detailed analysis of a Sagnac device in terms of non-inertial (i.e., rotating) coordinates is presented in Section 4.8, and discussed from a different point of view in Section 5.1. For the present, let's confine our attention to inertial coordinates, and demonstrate how a Sagnac device is described in terms of instantaneously co-moving inertial frames of an arbitrary point on the perimeter.

Suppose we've sent a sequence of momentary pulses around the loop, at one-second intervals, in both directions, and we have photo-detectors on each mirror to detect when they are struck by a co-rotating or counter-rotating pulse. Clearly the pulses will strike each mirror at one-second intervals from both directions (though not necessarily synchronized) because if they were arriving more frequently from one direction than from the other, the secular lag between corresponding pulses would be constantly increasing, which we know is not the case. So each mirror is receiving one pulse per second from both directions.  Furthermore, a local measurement of light speed performed (over a sufficiently short period of time) by an observer riding along at a point on the perimeter will necessarily show the speed of light to be c in all direction with respect to his instantaneously co-moving inertial coordinates. However, this system of coordinates is co-moving with only one particular point on the rim. At other points on the rim these coordinates are not co-moving, and so the speed of light is not c at other points on the rim with respect to these coordinates.

To describe this in detail, let's first analyze the Sagnac device from the hub-centered inertial frame. Throughout this discussion we assume an n-sided polygonal loop where n is very large, so the segment between any two adjacent mirrors subtends only a very small angle. With respect to the hub-centered frame each segment is moving with a velocity v parallel to the direction of travel of the light beams, so the situation on each segment is as plotted below in terms of hub-frame coordinates:

In this drawing, tf is the time required for light to cross this segment in the co-rotating direction, and tr is the time required for light to cross in the counter-rotating direction.  The difference between these two times, denoted by dt, is the incremental Sagnac effect for a segment of length dp on the perimeter.

Now, the ratio of dt/dp as a function of the rim velocity v can easily be read off this diagram, and we find that

This can be taken as a measure of the anisotropy over an incremental segment with respect to the hub frame. (Notice that this anisotropy with respect to the conventional relativistic spacetime decomposition for any inertial frame is actually in the distance traveled, not the speed of travel.) All the segments are symmetrical in this frame, so they all have this same anisotropy. Therefore, we can determine the total difference in travel times for co-rotating and counter-rotating beams of light making a complete trip around the loop by integrating dt around the perimeter. Thus we have

Substituting wr in place of v in the numerator, and noting that the enclosed area is A = pr2, we again arrive at the result T = 4Aw/(c2 - v2).

Now let's analyze the loop with respect to one of our tangential frames of reference, i.e., an inertial frame that is momentarily co-moving with one of the segments on the rim. If we examine the situation on that particular segment in terms of its own co-moving inertial frame we find, not surprisingly, the situation shown below:

This shows that dt/dp = 0, meaning no anisotropy at all. Nevertheless, if the light beams are allowed to go all the way around the loop, their total travel times will differ by T as computed above, so how does that difference arise with respect to this tangential frame?

Notice that although dt/dp equals zero at this tangent point with respect to the tangent frame, segments 90 degrees away from this point have the same anisotropy as we found for all the segments relative to the hub frame, namely, dt/dp = 2v/(c2 - v2), because the velocity of those two segments relative to our tangential frame is exactly v along the direction of the light rays, just as it was with respect to the hub frame. Furthermore, the segment 180 degrees away from our tangent segment has twice the anisotropy as it has with respect to the original hub-frame inertial coordinates, because that segment has a velocity of 2v with respect to our tangential frame.

In general, the anisotropy dt/dp can be computed for any segment on the loop simply by determining the projection of that segment's velocity (with respect our tangential frame) onto the axis of the light rays. This gives the results illustrated below, showing the ratio of the tangential frame anisotropy to the hub frame anisotropy:

It's easy to show that

where q is the angle relative to the tangent point. To assess the total difference in arrival times for light rays going around the loop in opposite directions, we need to integrate dt by dp around the perimeter. Noting that q equals p/r, we have

which again equals 4Aw/(c2 - v2), in agreement with the hub frame analysis. Thus, although the anisotropy is zero at each point on the rim's surface when evaluated with respect to that point's co-moving inertial frame, we always arrive at the same overall non-zero anisotropy for the entire loop. This was to be expected, because the absolute physical situation and intervals are the same for all inertial frames. We're simply decomposing those absolute intervals into space and time components in different ways.

The union of all the "present" time slices of the sequence of instantaneous co-moving inertial coordinate systems for a point fixed on the rim of a rotating disk, with each time slice assigned a time coordinate equal to the proper time of the fixed point, constitutes a coherent and unambiguous coordinate system over a region of spacetime that includes the entire perimeter of the disk. The general relation for mapping the proper time of one worldline into another by means of the co-moving planes of simultaneity of the former is derived at the end of Section 2.9, where it is shown that the derivative of the mapped time from a point fixed on the rim to a point at the same radius fixed in the hub frame is positive provided the rim speed is less than c. Of course, for locations further from the center of rotation the planes of simultaneity of a revolving point fixed on the rim will be become "retrograde", i.e., will backtrack, making the coordinate system ambiguous. This occurs for locations at a distance greater than 1/a from the hub, where  a  is the acceleration of the point fixed on the rim.

It's also worth noting that the amount of angular travel of the device during the time it takes for one pair of light pulses to circumnavigate a circular loop is directly proportional to the net "anisotropy" in the travel times. To prove this, note that in a circular Sagnac device of radius R the beam of light in the direction of rotation travels a distance of (2p - wt1)R and the other beam goes a distance of (2p + wt2)R where t1 and t2 are the travel times of the two beams, and w is the angular velocity of the loop. The travel times of the beams are just these distances divided by c, so we have

Solving for the times gives

so the difference in times is

where A = 2pR2  and v = wR.  The "anisotropic ratio" is the ratio of the travel times, which is

Solving this for wR gives

Letting q denote the angular travel of the loop during the travel of the two light beams, we have

Substituting for wR this reduces to

Therefore, the amount by which the ratio of travel times differs from 1 is exactly proportional to the angle through which the loop rotates during the transit of light, and this is true independent of R. (Of course, increasing the radius has the effect of increasing the difference between the travel times, but it doesn't alter the ratio.)

It's worth emphasizing that the Sagnac effect is purely a classical, not a relativistic phenomenon, because it's a "differential device", i.e., by running the light rays around the loop in opposite directions and measuring the time difference, it effectively cancels out the "transverse" effects characteristic of truly relativistic phenomenon. For example, the length of each incremental segment around the perimeter is shorter by a factor of [1-(v/c)2]1/2 in the hub based frame than in it's co-moving tangential frame, but this factor applies in both directions around the loop, so it doesn't affect the differential time. Likewise a clock on the perimeter moving at the speed v runs slow, in accord with special relativity, but the frequency of the light source is correspondingly slow, and this applies equally in both directions, so this does not affect the phase difference at the receiver. Thus, a pure Sagnac apparatus does not discriminate between relativistic and pre-relativistic theories (although it does rule out ballistic theories, ala Ritz). Ironically, this is the main reason it comes up so often in discussions of relativity, because the effect can easily be computed on a non-relativistic basis (as we did above for a circular loop, taking the sums c+v and c-v to determine the transit times in the two directions). Of course, if the light traveling around the loop passes through moving media with indices of refraction differing significantly from unity, then the Fizeau effect must also be taken into account, and in this case the results, while again perfectly consistent with special relativity, are quite problematic for any non-relativistic ether-based interpretation.

As mentioned above, as early as 1904 Michelson had proposed using such a device to measure the rotation of the earth, but he hadn't pursued the idea, since measurements of absolute rotation are fairly commonplace (e.g. Focault’s pendulum). Nevertheless, he (along with Gale) agreed to perform the experiment in 1925 (at considerable cost) at the urging of "relativists", who wished him to verify the shift of 236/1000 of a fringe predicted by special relativity. This was intended mainly to refute the ballistic theory of light propagation, which predicts zero phase shift (for a circular device). Michelson was not enthusiastic, since classical optics on the assumption of a stationary ether predicted exactly the same shift does special relativity (as explained above). He said

We will undertake this, although my conviction is strong that we shall prove only that the earth rotates on its axis, a conclusion which I think we may be said to be sure of already.

As Harvey Lemon wrote in his biographical sketch of Michelson, "The experiment, performed on the prairies west of Chicago, showed a displacement of 230/1000, in very close agreement with the prediction. The rotation of the Earth received another independent proof, the theory of relativity another verification. But neither fact had much significance." Michelson himself wrote that "this result may be considered as an additional evidence in favor of relativity - or equally as evidence of a stationary ether".

The only significance of the Sagnac effect for special relativity (aside from providing another refutation of ballistic theories) is that although the effect itself is of the first order in v/c, the qualitative description of the local conditions on the disk in terms of inertial coordinates depends on second-order effects. These effects have been confirmed empirically by, for example, the Michelson-Morley experiment. Considering the Earth as a particle on a large Sagnac device as it orbits around the Sun, the ether drift experiments demonstrate these second-order effects, confirming that the speed of light is indeed invariant in terms of relatively moving systems of inertial coordinates.

Return to Table of Contents

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Special Relativity and the Sagnac Effect

Copyright ? Walter Babin
Update Sept. 10, 2002
Addendum: Jun. 19, 2005: See the paper, Fizeau's Experiment With Moving Water: New Explanation, by G. & V. Sokolov for further evidence of compound velocities.

---------------

The constancy of the speed of light in each frame of reference logically results in compound light speeds (c+v)(c-v) for all frames in uniform motion relative to an observer. This is the de facto explanation for the Sagnac effect. No other is required.

The logic is as follows:
If, according to the Michelson-Morley experiments and Galilean relativity, the speed of light is constant at [c] in each frame of reference,

1. Light must travel a distance d = (c+v) in time t or (c-v)t in the opposite direction in the moving frame as measured in the reference frame of a "fixed" observer, or,
2. Space (or a combination of space-time) must contract in the direction of motion, or contrary to relativistic doctrine, expand in the case where the light wave is opposite to the direction of motion, by the value, [vt].

(Regarding ring lasers, the distance (d) is fixed at 2πR and the time taken is t1 = d/(c-v) and t2 = d/(c+v) respectively. The difference, t1 - t2 = 2dv/c2 - v2)

Relativists will claim the Sagnac effect is valid in relativity, thereby sanctioning the precise opposite of what the theory was to achieve, which is a single wave front common to both observers! A moment's reflection will convince you that without this objective, the theory is redundant. (see Relativistic Kinematics)

An interesting and equally logical result of the Michelson-Morley experiment is the negation of a universal aether for light propagation in favour of a continuum specific to each frame of reference (see The Nature of Light).

Furthermore, early spectrometric experiments with particle trajectories in magnetic fields led to the erroneous conclusion that mass increased with velocity. The velocity is the resultant effect of an impulse and cannot in any way be considered a cause. Although induced fields opposing the initial field had been know from the time of Faraday, this explanation was completely ignored. A detailed assessment of the equations of relativity identifies this to be the reason and no change in mass is evident. There are no partial electrons. (See Relativistic Dynamics)

Earlier Comment:
Variations in the speed of light due to polarity and in particular, the Sagnac effect led me to the conclusion that the latter contained the experimental evidence for a new theoretical basis for SRT dynamics without the obvious contradictions contained in its kinematic assumptions.

Fundamental to this concept is that the dynamic effects predicted by SRT as derived from the motion of an object are in fact the direct result of accelerations (linear or otherwise) that produced the motion and can be resolved within the general framework of classical mechanics and electrodynamics. To be specific; the mass increase of a particle is the result of acceleration, producing not only an increase in kinetic energy but of its potential. With respect to moving charges, a parallel modification of field characteristics is obvious and may exclusively account for the experimentally calculated mass increase. In either instance, the effects remain constant, provided no change of state is imposed (inertial frames of reference and the first law of mechanics).

A retrospective assessment of experiments from the Compton effect through particle physics to the confirmation of mass-energy equivalence (and the dualism) contained in the work of Dirac make it evident that no further assumptions are required, particularly with respect to time and space (eg. the life-span of the u-meson). It does not contain a significant departure from the results of modern experimental physics and its classical antecedents and therein lies its strength. Furthermore, placing these experiments on a sound theoretical foundation will have a profound effect on future developments.

July 1, 1999

作者: llgzcts 时间: 2007-11-14 13:48
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作者: kxjh 时间: 2007-11-14 16:44
解释这个试验其实很简单，用不相对论的，

作者: kxjh 时间: 2007-11-14 16:52
不好意思，刚才按错键了
即不是光速可变也不是多普勒效应，而恰恰是光速不变！
问题的关键是发生干涉的位置是运动的，而两束光相对这个位置运动的方向是相反的，结果是一束光少跑了一段而另一束光多跑了一段，从而产生了光程差，导致干涉条纹移动

作者: llgzcts 时间: 2007-11-14 18:14
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作者: willcao 时间: 2007-11-14 22:00
先顶一下，改天再研究

作者: kxjh 时间: 2007-11-15 09:21
标题: 回复 #22 llgzcts 的帖子
正因为是运动才会出现干涉条纹的移动，如果静止干涉条纹就不动了

先说一下，你提到的文章的错误：
既然这个试验观测到了干涉条纹的移动现象，说明这个试验在转动前和转动后都发生了光的干涉现象，光的（或说波的）干涉条件是“频率相同、振动方向相同、相遇点相位差恒定”，可得到如下结论：
1、光是一种波
2、光的频率在转动前后不变或变化量相同（如不满足则不能发生干涉现象）
3、光的波长在转动前后不变（如不满足则干涉条纹的形态将发生变化而不单单是条纹移动）
由1得光的速度=波长*频率，由2和3知两束光的速度在转动前后不变（因为同时变快或变慢是不可能的），且不可能出现两束光一个变快另一个变慢！

作者: llgzcts 时间: 2007-11-15 12:58
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作者: kxjh 时间: 2007-11-15 13:04
标题: 回复 #25 llgzcts 的帖子
见21楼。你把光路假想为圆的，可能更好理解一点

作者: llgzcts 时间: 2007-11-15 13:15
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作者: the2 时间: 2007-11-15 13:50
同一束光在同一介质下传输，产生红移时的速度和紫移时的速度是不是一样？
答案是一样的，变的只不过是相位和频率。这个试验的结果和天文观测中的很多现象类似嘛。

[ 本帖最后由 the2 于 2007-11-15 13:52 编辑 ]

作者: kxjh 时间: 2007-11-15 15:49
标题: 回复 #28 the2 的帖子
如果发生了红移和紫移，则两束光的频率将不同，也就不能发生干涉了！

作者: the2 时间: 2007-11-15 16:57
http://www.sea3000.net/qiji/2.php
这里有篇文章说得不错，赞成它的解释

作者: kxjh 时间: 2007-11-15 17:07

原帖由 llgzcts 于 2007-11-15 13:15 发表

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这是地面上的观测者的观点.
问题是对在转盘上的观测者来说,他是如何解释这个实验结果的?

这个还没想出个好的解释！
但绝对不是光速变化！如果光速改变，则两束光的频率和波长至少有一个不相同，频率不同则不发生干涉，波长不同则干涉条纹变化

作者: kxjh 时间: 2007-11-15 17:23
发重了

[ 本帖最后由 kxjh 于 2007-11-15 17:30 编辑 ]

作者: willcao 时间: 2007-11-15 18:59
我觉得这样的实验还是比较粗糙的，可能里边有很多对实验结果有影响的因素没有考虑进去，所以以此为依据说明问题的可靠程度比较低。可以比较一下，当初爱丁顿作日食观测实验同样具有很多有重要影响的方面，但是在解释实验结果的时候都没有考虑，只是得出了支持“相对论”的实验结果，现在大家对这个实验可能都不是很看重了。可是其中的教训是值得我们总结的，简单说来还是实验太粗糙，没有说服力。
现在再说我对上面提到的萨纳克的实验的个人想法：试验设施我是没有十分搞清楚，但我还是要先提出我的担心，在实验台作圆周加速时，镜片支架就没有受力变形吗？如果有受力变形那干涉条纹的移动就要考虑其他因素的影响了。
当然我也还是没有深入到这个实验的原理层次去研究，我的脑袋还是不够转的阿

作者: llgzcts 时间: 2007-11-15 19:32
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作者: the2 时间: 2007-11-15 20:05
这篇新闻里看不出来光速可变啊，相位延迟与运动速度以及光波导长度在运动方向上的投影成正比
，而以运动类型及光波导折射率无关。----这是实验的广义效果，所以叫普适萨格纳克效应。
<b>（其中c为真空中的光速。。。。）</b>

[ 本帖最后由 the2 于 2007-11-15 20:29 编辑 ]

作者: llgzcts 时间: 2007-11-15 20:40
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作者: the2 时间: 2007-11-15 21:00
我不是承认或认定无形态物质也不是就承认或认定以太的存在，只是认为符合观测结果的理论解释是当前最好的解释，在它能够广泛的推导或提前预测出其他实验的结果前并不能认为就是完全的真理。（是不是有点滑头

，不过这对不死抱教条，能接受新的观点有好处。）
能量-质量-引力-空间-场运动-时间这一系列名词里面，以太或类似的东西能不能够存在

还需要大量的实验观测数据来验证。
我们在这里吹吹牛可以，不用太较真了。如果再上升到哲学的高度去，有大海一样多的口水都不够用啊！

作者: llgzcts 时间: 2007-11-15 21:01
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作者: llgzcts 时间: 2007-11-15 21:09
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作者: the2 时间: 2007-11-15 21:44
　　一些物理学家认为，地球在以太中的运动会制造出一种“以太气流”，这种气流会使得光波发生弯曲，就好像声波在大气气流中发生偏移一样。但以太理论在1887年艾伯特-迈克耳逊（1907年诺贝尔物理学奖得主，以表彰他对光学精密仪器及用之于光谱学与计量学研究所作的贡献，他以精密测量光的速度和以空前精密度进行以太漂移实验而闻名于世）同爱德华-摩尔利（实验测量出光速变化的美国天文学家）的试验失败后，在很大程度上被就此搁置一旁。

　　迈克耳逊-摩尔利的试验建立在这样一个基础上，假定整个空间充满着光以太，人们认为以太是不动的，地球运行时通过以太。因此，顺地球运动方向发出的光传播得应该（或看来应该）比向与地球运动方向成直角发出的光快些。两束光会失相并出现干涉条纹。测量条纹的宽度就可能求出地球相对于以太的精确速度。这样，便可以测定地球的“绝对运动”，还将由宇宙间一切物体相对于地球的运动得知它们的绝对运动。但试验的最终结果却是看不到有明显宽度的条纹，因此光速在任何环境下任何方向上都没有差别。从而也推翻了所有关于以太的学说。这一意味着“以太气流”可能不存在。后来爱因斯坦在自己的狭义相对论的基础上表明，光可以在“没有以太”的真空中进行传播。

　　但斯塔克曼关于“以太”的概念理解同十九世纪时所理解的“以太”概念又存在很大不同，斯塔克曼认为，“以太”对重力产生影响，而不是对光的运动产生影响。斯塔克曼说：“在传统的重力模型中，科学家们使用被重物压住发生弯曲的橡胶板来显示其受重力情况。”斯塔克曼解释了在他的理论中“以太”是如何发生作用的。“当以太物质遍布周围时，橡胶板变得十分柔软。所以当上面承受重物时，其所受的重力影响要大的多。”斯塔克曼通过初步计算提出，以太对重力的影响可以解释为什么星系内部的恒星能够以如此高的速率进行运动。

　　斯塔克曼研究的下一步将着重于进行更多、更详细的计算来保证他提出的“以太”理论能够同现有的宇宙资料想吻合，如太阳系中各行星的运动。斯塔克曼说：“进行这些试验十分重要，因为很有可能我们会推翻暗物质理论，或者说进行这些试验将使得我们对‘以太’理论的信心进一步增加。从这个层面上来说，在没有确切证明之前，我认为目前两种对立的理论应该并存。”

倒相对论
相对论的提出，同样受到很多的指责，有很多人认为它是错误的，并大大阻碍了社会的发展。然而这种观点并不被主流科学界所接受。
观点如下：
1、推翻光的波粒二象性，即证明光只是波，或光只是粒子

2、推翻光速不变定律，即证明存在以太或存在绝对坐标 （既然你不接受其他的观点，那祝你早日验证它）

3、证明牛顿理论的正确性

作者: llgzcts 时间: 2007-11-16 12:56
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作者: 紫月霓裳 时间: 2007-11-17 11:42

原帖由 llgzcts 于 2007-11-16 12:56 发表

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根据以上资料和《对以太、惯性和暗物质的新认识》一文，我提出以下观点：
１．物质的能量分布于它周围的整个空间（当然由近到远有一定梯度），这便形成了以太．
２．相对于均匀以太静止的参考系才是惯性系．
３．在惯性系中，光速不变．
４．在相对于 ...

１．你所讲的以太与时空引力场的定义是相同的，没有必要再改回以太这个名字．
２．广义相对论的时空中没有绝对的惯性系，因为时空引力场的强度不是绝对均匀的．
３．根据第２条可知，在任何范围（除非是绝对真空）测量的光速都不会是绝对光速，因为时空场强度是不均匀的，被测量的光线经过不同强度的时空引力场再回到观测者的参考系，以观测者参考系中的时间流来计算光速是不正确的．这点与相对论的光速不变并不矛盾喔．
４．在引力场中不止是光速变化了，时间的流逝速率同样在变化，在地球表面离地表近则时空引力场强度大，时间流逝速率慢，光速相对于真空也会比较慢．所以光速与时间的同步变化保持光速在任何参考系中都是不变的．但前提是以该参考系中的时间速率来衡量该参考系中的光速．

　　似乎楼主并没有了解相对论中光速不变的原理呢．

作者: 紫月霓裳 时间: 2007-11-17 11:43

原帖由 llgzcts 于 2007-11-16 12:56 发表

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根据以上资料和《对以太、惯性和暗物质的新认识》一文，我提出以下观点：
１．物质的能量分布于它周围的整个空间（当然由近到远有一定梯度），这便形成了以太．
２．相对于均匀以太静止的参考系才是惯性系．
３．在惯性系中，光速不变．
４．在相对于 ...

看不明白楼主第４点想要表达的想法．

作者: llgzcts 时间: 2007-11-17 12:51
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作者: llgzcts 时间: 2007-11-17 12:55
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作者: 紫月霓裳 时间: 2007-11-17 13:26
标题: 回复 #45 llgzcts 的帖子
　　所以以太不存在！存在的是时空引力场，区别在于时空引力场中光速与时间和空间联动，而光速在人们设想的＂以太＂中与时间和空间不联动．广义相对论中的光速相对于任何参考系都是不变的，但不能用一个引力场强度的参考系的时间去衡量另一个引力场强度参考系中的光速，明白了吗？

作者: llgzcts 时间: 2007-11-17 13:39
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作者: 紫月霓裳 时间: 2007-11-17 19:33
标题: 回复 #47 llgzcts 的帖子
　　至少我可以肯定当转盘的角速度改变时处于转盘上的观测者同样会看到干涉条纹移动，因为在转动速度变化的瞬间两束方向不同的光其频率肯定会发生相反的变化．

[ 本帖最后由紫月霓裳于 2007-11-18 09:43 编辑 ]

作者: llgzcts 时间: 2007-11-17 22:11
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作者: 紫月霓裳 时间: 2007-11-18 10:13

原帖由 llgzcts 于 2007-11-17 22:11 发表

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干涉是同频率的两束光由于相位不同而引起的.即使转盘匀速转动,萨格纳克干涉实验也会看到干涉条纹的移动.

由于两速光的传播方向不同，即使转盘匀速旋转两束光的频率也有微小的差异，其大小与转盘的转速成正比．并且这个实验中光线１是经过Ｍ１透镜的，而光线２是被Ｍ１透镜反射的光线，在不同介质中的光速是不同的，怎么证明是光速本身变化了？

作者: llgzcts 时间: 2007-11-18 13:41
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作者: 紫月霓裳 时间: 2007-11-18 17:38
　　频率接近的两束光才会发生干涉，在转盘转速不是很高的情况下干涉一定会发生的，我认为观测者无论是在轮盘上的相对静止参考系还是远处的相对运动参考系都会看到干涉条纹的移动．
　　首先可以肯定这个实验根本无法否定光速不变原理，因为干涉条纹的移动与光速是根本无关的．在不同参考系中看到的光速一样，不同的只是频率与波长，只有当两个不同参考系中的人看同一束光波却得到相同的波长与频率才能证明光速是变化的．我不知道你想说的是什么．

作者: worren 时间: 2007-11-18 18:29
最后给一个建议，楼主把自己读过的文章原稿和出处核实后再做总结分析。
现在楼主处于一种状态，这种状态属于——已经被各种胡编乱造、捏造事实的垃圾文章骗成了没头苍蝇乱转。
爱因斯坦的文章“论以太”原文是《以太与相对论》（ETHER AND THE THEORY OF RELATIVITY），其中以太的含义也不是“光的介质”，而是以引力场来解释，从而为以后的引力场论奠定了基础:
http://www.zionism-israel.com/Albert_Einstein/Albert_Einstein_Ether_Relativity.htm
ETHER AND THE THEORY OF RELATIVITY
An Address delivered on May 5th, 1920, in the University of Leyden
How does it come about that alongside of the idea of ponderable matter, which is derived by abstraction from everyday life, the physicists set the idea of the existence of another kind of matter, the ether? The explanation is probably to be sought in those phenomena which have given rise to the theory of action at a distance, and in the properties of light which have led to the undulatory theory. Let us devote a little while to the consideration of these two subjects.
Outside of physics we know nothing of action at a distance. When we try to connect cause and effect in the experiences which natural objects afford us, it seems at first as if there were no other mutual actions than those of immediate contact, e.g. the communication of motion by impact, push and pull, heating or inducing combustion by means of a flame, etc. It is true that even in everyday experience weight, which is in a sense action at a distance, plays a very important part. But since in daily experience the weight of bodies meets us as something constant, something not linked to any cause which is variable in time or place, we do not in everyday life speculate as to the cause of gravity, and therefore do not become conscious of its character as action at a distance. It was Newton抯 theory of gravitation that first assigned a cause for gravity by interpreting it as action at a distance, proceeding from masses. Newton抯 theory is probably the greatest stride ever made in the effort towards the causal nexus of natural phenomena. And yet this theory evoked a lively sense of discomfort among Newton抯 contemporaries, because it seemed to be in conflict with the principle springing from the rest of experience, that there can be reciprocal action only through contact, and not through immediate action at a distance. It is only with reluctance that man抯 desire for knowledge endures a dualism of this kind. How was unity to be preserved in his comprehension of the forces of nature? Either by trying to look upon contact forces as being themselves distant forces which admittedly are observable only at a very small distance--and this was the road which Newton抯 followers, who were entirely under the spell of his doctrine, mostly preferred to take; or by assuming that the Newtonian action at a distance is only apparently immediate action at a distance, but in truth is conveyed by a medium permeating space, whether by movements or by elastic deformation of this medium. Thus the endeavour toward a unified view of the nature of forces leads to the hypothesis of an ether. This hypothesis, to be sure, did not at first bring with it any advance in the theory of gravitation or in physics generally, so that it became customary to treat Newton抯 law of force as an axiom not further reducible. But the ether hypothesis was bound always to play some part in physical science, even if at first only a latent part.
When in the first half of the nineteenth century the far-reaching similarity was revealed which subsists between the properties of light and those of elastic waves in ponderable bodies, the ether hypothesis found fresh support. It appeared beyond question that light must be interpreted as a vibratory process in an elastic, inert medium filling up universal space. It also seemed to be a necessary consequence of the fact that light is capable of polarisation that this medium, the ether, must be of the nature of a solid body, because transverse waves are not possible in a fluid, but only in a solid. Thus the physicists were bound to arrive at the theory of the 搎uasi-rigid?luminiferous ether, the parts of which can carry out no movements relatively to one another except the small movements of deformation which correspond to light-waves.
This theory--also called the theory of the stationary luminiferous ether--moreover found a strong support in an experiment which is also of fundamental importance in the special theory of relativity, the experiment of Fizeau, from which one was obliged to infer that the luminiferous ether does not take part in the movements of bodies. The phenomenon of aberration also favoured the theory of the quasi-rigid ether.
The development of the theory of electricity along the path opened up by Maxwell and Lorentz gave the development of our ideas concerning the ether quite a peculiar and unexpected turn. For Maxwell himself the ether indeed still had properties which were purely mechanical, although of a much more complicated kind than the mechanical properties of tangible solid bodies. But neither Maxwell nor his followers succeeded in elaborating a mechanical model for the ether which might furnish a satisfactory mechanical interpretation of Maxwell抯 laws of the electro-magnetic field. The laws were clear and simple, the mechanical interpretations clumsy and contradictory. Almost imperceptibly the theoretical physicists adapted themselves to a situation which, from the standpoint of their mechanical programme, was very depressing. They were particularly influenced by the electro-dynamical investigations of Heinrich Hertz. For whereas they previously had required of a conclusive theory that it should content itself with the fundamental concepts which belong exclusively to mechanics (e.g. densities, velocities, deformations, stresses) they gradually accustomed themselves to admitting electric and magnetic force as fundamental concepts side by side with those of mechanics, without requiring a mechanical interpretation for them. Thus the purely mechanical view of nature was gradually abandoned. But this change led to a fundamental dualism which in the long-run was insupportable. A way of escape was now sought in the reverse direction, by reducing the principles of mechanics to those of electricity, and this especially as confidence in the strict validity of the equations of Newton抯 mechanics was shaken by the experiments with β-rays and rapid Kathode rays.
This dualism still confronts us in unextenuated form in the theory of Hertz, where matter appears not only as the bearer of velocities, kinetic energy, and mechanical pressures, but also as the bearer of electromagnetic fields. Since such fields also occur in vacuo--i.e. in free ether--the ether also appears as bearer of electromagnetic fields. The ether appears indistinguishable in its functions from ordinary matter. Within matter it takes part in the motion of matter and in empty space it has everywhere a velocity; so that the ether has a definitely assigned velocity throughout the whole of space. There is no fundamental difference between Hertz抯 ether and ponderable matter (which in part subsists in the ether).
The Hertz theory suffered not only from the defect of ascribing to matter and ether, on the one hand mechanical states, and on the other hand electrical states, which do not stand in any conceivable relation to each other; it was also at variance with the result of Fizeau抯 important experiment on the velocity of the propagation of light in moving fluids, and with other established experimental results.
Such was the state of things when H. A. Lorentz entered upon the scene. He brought theory into harmony with experience by means of a wonderful simplification of theoretical principles. He achieved this, the most important advance in the theory of electricity since Maxwell, by taking from ether its mechanical, and from matter its electromagnetic qualities. As in empty space, so too in the interior of material bodies, the ether, and not matter viewed atomistically, was exclusively the seat of electromagnetic fields. According to Lorentz the elementary particles of matter alone are capable of carrying out movements; their electromagnetic activity is entirely confined to the carrying of electric charges. Thus Lorentz succeeded in reducing all electromagnetic happenings to Maxwell抯 equations for free space.
As to the mechanical nature of the Lorentzian ether, it may be said of it, in a somewhat playful spirit, that immobility is the only mechanical property of which it has not been deprived by H. A. Lorentz. It may be added that the whole change in the conception of the ether which the special theory of relativity brought about, consisted in taking away from the ether its last mechanical quality, namely, its immobility. How this is to be understood will forthwith be expounded.
The space-time theory and the kinematics of the special theory of relativity were modelled on the Maxwell-Lorentz theory of the electromagnetic field. This theory therefore satisfies the conditions of the special theory of relativity, but when viewed from the latter it acquires a novel aspect. For if K be a system of co-ordinates relatively to which the Lorentzian ether is at rest, the Maxwell-Lorentz equations are valid primarily with reference to K. But by the special theory of relativity the same equations without any change of meaning also hold in relation to any new system of co-ordinates K′ which is moving in uniform translation relatively to K. Now comes the anxious question:--Why must I in the theory distinguish the K system above all K′ systems, which are physically equivalent to it in all respects, by assuming that the ether is at rest relatively to the K system? For the theoretician such an asymmetry in the theoretical structure, with no corresponding asymmetry in the system of experience, is intolerable. If we assume the ether to be at rest relatively to K, but in motion relatively to K′, the physical equivalence of K and K′ seems to me from the logical standpoint, not indeed downright incorrect, but nevertheless unacceptable.
The next position which it was possible to take up in face of this state of things appeared to be the following. The ether does not exist at all. The electromagnetic fields are not states of a medium, and are not bound down to any bearer, but they are independent realities which are not reducible to anything else, exactly like the atoms of ponderable matter. This conception suggests itself the more readily as, according to Lorentz抯 theory, electromagnetic radiation, like ponderable matter, brings impulse and energy with it, and as, according to the special theory of relativity, both matter and radiation are but special forms of distributed energy, ponderable mass losing its isolation and appearing as a special form of energy.
More careful reflection teaches us, however, that the special theory of relativity does not compel us to deny ether. We may assume the existence of an ether; only we must give up ascribing a definite state of motion to it, i.e. we must by abstraction take from it the last mechanical characteristic which Lorentz had still left it. We shall see later that this point of view, the conceivability of which I shall at once endeavour to make more intelligible by a somewhat halting comparison, is justified by the results of the general theory of relativity.
Think of waves on the surface of water. Here we can describe two entirely different things. Either we may observe how the undulatory surface forming the boundary between water and air alters in the course of time; or else--with the help of small floats, for instance--we can observe how the position of the separate particles of water alters in the course of time. If the existence of such floats for tracking the motion of the particles of a fluid were a fundamental impossibility in physics--if, in fact, nothing else whatever were observable than the shape of the space occupied by the water as it varies in time, we should have no ground for the assumption that water consists of movable particles. But all the same we could characterise it as a medium.
We have something like this in the electromagnetic field. For we may picture the field to ourselves as consisting of lines of force. If we wish to interpret these lines of force to ourselves as something material in the ordinary sense, we are tempted to interpret the dynamic processes as motions of these lines of force, such that each separate line of force is tracked through the course of time. It is well known, however, that this way of regarding the electromagnetic field leads to contradictions.
Generalising we must say this:--There may be supposed to be extended physical objects to which the idea of motion cannot be applied. They may not be thought of as consisting of particles which allow themselves to be separately tracked through time. In Minkowski抯 idiom this is expressed as follows:--Not every extended conformation in the four-dimensional world can be regarded as composed of world-threads. The special theory of relativity forbids us to assume the ether to consist of particles observable through time, but the hypothesis of ether in itself is not in conflict with the special theory of relativity. Only we must be on our guard against ascribing a state of motion to the ether.
Certainly, from the standpoint of the special theory of relativity, the ether hypothesis appears at first to be an empty hypothesis. In the equations of the electromagnetic field there occur, in addition to the densities of the electric charge, only the intensities of the field. The career of electromagnetic processes in vacuo appears to be completely determined by these equations, uninfluenced by other physical quantities. The electromagnetic fields appear as ultimate, irreducible realities, and at first it seems superfluous to postulate a homogeneous, isotropic ether-medium, and to envisage electromagnetic fields as states of this medium.
But on the other hand there is a weighty argument to be adduced in favour of the ether hypothesis. To deny the ether is ultimately to assume that empty space has no physical qualities whatever. The fundamental facts of mechanics do not harmonize with this view. For the mechanical behaviour of a corporeal system hovering freely in empty space depends not only on relative positions (distances) and relative velocities, but also on its state of rotation, which physically may be taken as a characteristic not appertaining to the system in itself. In order to be able to look upon the rotation of the system, at least formally, as something real, Newton objectivises space.
Since he classes his absolute space together with real things, for him rotation relative to an absolute space is also something real. Newton might no less well have called his absolute space 揈ther? what is essential is merely that besides observable objects, another thing, which is not perceptible, must be looked upon as real, to enable acceleration or rotation to be looked upon as something real.
It is true that Mach tried to avoid having to accept as real something which is not observable by endeavouring to substitute in mechanics a mean acceleration with reference to the totality of the masses in the universe in place of an acceleration with reference to absolute space. But inertial resistance opposed to relative acceleration of distant masses presupposes action at a distance; and as the modern physicist does not believe that he may accept this action at a distance, he comes back once more, if he follows Mach, to the ether, which has to serve as medium for the effects of inertia. But this conception of the ether to which we are led by Mach抯 way of thinking differs essentially from the ether as conceived by Newton, by Fresnel, and by Lorentz. Mach抯 ether not only conditions the behaviour of inert masses, but is also conditioned in its state by them.
Mach抯 idea finds its full development in the ether of the general theory of relativity. According to this theory the metrical qualities of the continuum of space-time differ in the environment of different points of space-time, and are partly conditioned by the matter existing outside of the territory under consideration. This space-time variability of the reciprocal relations of the standards of space and time, or, perhaps, the recognition of the fact that 揺mpty space? in its physical relation is neither homogeneous nor isotropic, compelling us to describe its state by ten functions (the gravitation potentials gμν), has, I think, finally disposed of the view that space is physically empty. But therewith the conception of the ether has again acquired an intelligible content, although this content differs widely from that of the ether of the mechanical undulatory theory of light. The ether of the general theory of relativity is a medium which is itself devoid of all mechanical and kinematical qualities, but helps to determine mechanical (and electromagnetic) events.
What is fundamentally new in the ether of the general theory of relativity as opposed to the ether of Lorentz consists in this, that the state of the former is at every place determined by connections with the matter and the state of the ether in neighbouring places, which are amenable to law in the form of differential equations; whereas the state of the Lorentzian ether in the absence of electromagnetic fields is conditioned by nothing outside itself, and is everywhere the same. The ether of the general theory of relativity is transmuted conceptually into the ether of Lorentz if we substitute constants for the functions of space which describe the former, disregarding the causes which condition its state. Thus we may also say, I think, that the ether of the general theory of relativity is the outcome of the Lorentzian ether, through relativation.
As to the part which the new ether is to play in the physics of the future we are not yet clear. We know that it determines the metrical relations in the space-time continuum, e.g. the configurative possibilities of solid bodies as well as the gravitational fields; but we do not know whether it has an essential share in the structure of the electrical elementary particles constituting matter. Nor do we know whether it is only in the proximity of ponderable masses that its structure differs essentially from that of the Lorentzian ether; whether the geometry of spaces of cosmic extent is approximately Euclidean. But we can assert by reason of the relativistic equations of gravitation that there must be a departure from Euclidean relations, with spaces of cosmic order of magnitude, if there exists a positive mean density, no matter how small, of the matter in the universe. In this case the universe must of necessity be spatially unbounded and of finite magnitude, its magnitude being determined by the value of that mean density.
If we consider the gravitational field and the electromagnetic field from the stand-point of the ether hypothesis, we find a remarkable difference between the two. There can be no space nor any part of space without gravitational potentials; for these confer upon space its metrical qualities, without which it cannot be imagined at all. The existence of the gravitational field is inseparably bound up with the existence of space. On the other hand a part of space may very well be imagined without an electromagnetic field; thus in contrast with the gravitational field, the electromagnetic field seems to be only secondarily linked to the ether, the formal nature of the electromagnetic field being as yet in no way determined by that of gravitational ether. From the present state of theory it looks as if the electromagnetic field, as opposed to the gravitational field, rests upon an entirely new formal motif, as though nature might just as well have endowed the gravitational ether with fields of quite another type, for example, with fields of a scalar potential, instead of fields of the electromagnetic type.
Since according to our present conceptions the elementary particles of matter are also, in their essence, nothing else than condensations of the electromagnetic field, our present view of the universe presents two realities which are completely separated from each other conceptually, although connected causally, namely, gravitational ether and electromagnetic field, or--as they might also be called--space and matter.
Of course it would be a great advance if we could succeed in comprehending the gravitational field and the electromagnetic field together as one unified conformation. Then for the first time the epoch of theoretical physics founded by Faraday and Maxwell would reach a satisfactory conclusion. The contrast between ether and matter would fade away, and, through the general theory of relativity, the whole of physics would become a complete system of thought, like geometry, kinematics, and the theory of gravitation. An exceedingly ingenious attempt in this direction has been made by the mathematician H. Weyl; but I do not believe that his theory will hold its ground in relation to reality. Further, in contemplating the immediate future of theoretical physics we ought not unconditionally to reject the possibility that the facts comprised in the quantum theory may set bounds to the field theory beyond which it cannot pass.
Recapitulating, we may say that according to the general theory of relativity space is endowed with physical qualities; in this sense, therefore, there exists an ether. According to the general theory of relativity space without ether is unthinkable; for in such space there not only would be no propagation of light, but also no possibility of existence for standards of space and time (measuring-rods and clocks), nor therefore any space-time intervals in the physical sense. But this ether may not be thought of as endowed with the quality characteristic of ponderable media, as consisting of parts which may be tracked through time. The idea of motion may not be applied to it.

如果英语不好，还可以费点钱财找翻译公司为自己收集有价值的资料；介绍一个翻译公司：
http://www.netat.net/，不要不知道什么是应该信任的东西；想找Einstein的文章，
去这里：http://www.albert-einstein.org/。
网友都有自己的工作生活，不可能什么问题都能抽空解决。

[ 本帖最后由 worren 于 2007-11-18 21:32 编辑 ]

作者: llgzcts 时间: 2007-11-18 21:32
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作者: worren 时间: 2007-11-18 21:39
标题: 回复 #54 llgzcts 的帖子
分不清什么是事实,什么是假设,这也不是你应该来的地方;
下面这个垃圾窝是适合你去的地方:
http://www.xdlbj.com/

作者: worren 时间: 2007-11-18 21:46
中国文盲有很多,老年文盲偶也见过不少,倚老卖老的更是一大堆,这样批你已经很给你留面子了.

作者: llgzcts 时间: 2007-11-19 03:10
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作者: llgzcts 时间: 2007-11-19 03:37
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作者: 紫月霓裳 时间: 2007-11-19 09:46
标题: 回复 #53 worren 的帖子
“网友都有自己的工作生活，不可能什么问题都能抽空解决。”？

　　有找网址与发贴子的时间问题或许早已解释清楚了，假如你回答不了或不想回答就不要回贴，有时间奚落人家却没有时间解答问题，明显是自己的态度有问题，这样的态度是无法做到客观与人讨论问题的。

作者: llgzcts 时间: 2007-12-4 22:43
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作者: worren 时间: 2007-12-5 12:26
实话实说，有些鸟不具备科学探讨的资格与品质。

作者: worren 时间: 2007-12-5 12:34
提出的话题如同“刘姥姥进大观园”

作者: llgzcts 时间: 2007-12-5 14:13
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