Is All Motion Linked to the Big Bang?

[selfAdjoint]

I think some of the questions can be answered by some quotes from MTW's Gravitation, at the start of their Chapter10,"Affine Geometry: Geodesics, Parallel Transport, and Covariant Derivative".

> Free fall is the "natural state of motion," so natural, in fact, that the path through spacetime of a freely falling, neutral test body is independent of its structure and composisiton (the "weak equivalence principle"...)

> Ask for the maximum amount of information tied up in each trajectory. Is it merely the sequence of points along which the test body falls? No; there is more. Each test body can carry a clock ([independent] of structure or composition of test body). The clock ticks as the body moves, labelling each event on its trajectory with a number: the time \lambda when the body was there. Result: the free-fall trajectory isnot just a sequence of points; it is a parametrized sequence, a "curve".

> in the curved spacetime of Einstein...these parametrized free-fall trajectories are the straightest of all possible curves. Consequently one gives these trajectories the same name, "geodesics", that mathematicians use for the straight lines of a curved manifold...

Finnally, from Chapter 13,
>Concord between locally straight lines and geodesics of curved spacetimes demands that timelike geodesics have extremal proper length...

 

[loseyourname]

The freefall concept works about the same way. You first have to accelerate up to the speed of gravity, and that's the only acceleration you feel.

You're a little bit off, because there is no such thing as a speed of gravity. Gravity pulls you downward at a constant rate of acceleration, meaning in a freefall, you are always moving faster. The only reason this is not, in fact, the case for a skydiver is because of air resistance, although if they dove head first, rather than splayed (which, of course, is why they do not dive head first), then they would be constanstly accelerated.

Anyway, Adjoint just gave a good explanation. I see what he was saying now. Maybe I'll read that book.

 

[loseyourname]

Here's a pretty damn good explanation:

What happens is that in non-euclidean geometries, the notion of 'straight line' gets a bit wierd.

Imagine an ant walking along the surface of a cylinder. Even though the ant is walking along a 'locally straight line' (a geodesic), it's walking along something that we (as outsiders) might percieve as a curved line. Similarly, if the ant is walking in a locally straight line on a moving turtable, although the ant is moving in a locally straight line, the path it describes is not straight.

Classically, it's assumed that space-time is euclidean (or flat), so a 'locally straight' line is also a straight line. And that gravity is a force that perturbs motion that would otherwise go along this straight line. Einstein postulated that the path that an object takes under the influence of gravity is the 'locally straight' path. This is intemately related to the notion that gravitational and inertial massess are the same. Since we can describe the paths that objects take under the influence of gravity, we can plot them, and describe the 'shape' of space-time.

It's also worth noting that for GR to work, you have to imagine a 4D warped space (which would be embedded in 5-space) and not a 3D space, since GR includes time as one of the dimensions.

 

[p-brane]

Speaking of motion.

Is it only light that (appears to) travel as fast as light?

Does this include the full spectrum of light like ultra-violet, gamma, X radiation, infa-red and the ones I haven't mentioned? Thanks.

 

[Les Sleeth]

Is it only light that (appears to) travel as fast as light?

You're a little bit off, because there is no such thing as a speed of gravity.

Actually, fairly recently I believe, gravity was confirmed to travel at light speed.

 

[Les Sleeth]

The misnamed g-forces that pilots feel during maneuvers have nothing to do with gravity. From a spacetime viewpoint, those maneuvers are highly non-geodesic.

Something I've wondered is, since there is no way for an observer in an accelerating frame of reference to distinguish between "g-force" and gravity, is it possible both are related to the some single underlying physical law? I believe I've heard that some thinkers postulate an as yet undetected field might exist in space (the Higgs field?) which sits dormant until either mass or acceleration take place with in it, which then causes the field to constrict in proportion to the object's mass or the force of acceleration. I always thought that made sense because both mass and force are due to energy concentrations.

 

[loseyourname]

Actually, fairly recently I believe, gravity was confirmed to travel at light speed.

That statement was made in reference to the speed of a falling object pulled by gravity, not the speed of the propagation of gravity waves, which as far as we can tell, do travel at the speed of light. In contrast, a falling object will never move at constant speed in the absence of air resistance.

 

[Les Sleeth]

That statement was made in reference to the speed of a falling object pulled by gravity, not the speed of the propagation of gravity waves, which as far as we can tell, do travel at the speed of light. In contrast, a falling object will never move at constant speed in the absence of air resistance.

Well, mostly I wanted to answer p-brane (very funny handle!), but forgot to include his quote initially. And then I started wondering what you meant when you said "there is no speed of gravity." I thought I understood mikesvenson's meaning when he said "reaching the speed of gravity." I figured he was referring to getting to the point where any initial boost or retardation was overcome, and one was falling in synch with the force of gravity. So I couldn't see why you said he was "off" unless you were talking about something else, and hadn't heard about the recent confirmation of predictions about the speed of gravity waves.

Getting back to the question of what is motion (a great question I think) . . . defining it by formulas and pointing out the special circumstances of relativity doesn't (philosophically speaking) explain what the heck it is.

I've thought that in the current conditions of our universe, motion wouldn't be possible without entropy. It seems both motion and change are related to the "winding down" of our universe. Motion, for example, has been the agent of change since the big bang.

 

[p-brane]

There is a speed of [the effect of gravity. Gravity, as a source of the effect, stays where it is: in my book at least.

The most important part of my question is whether or not gamma, Xradiation, Ultraviolet waves, Infared, neutrinos and other incidental electromagnetic spectrums all "travel" at the "speed of light". (?)

 

[Les Sleeth]

There is a speed of [the effect of gravity. Gravity, as a source of the The most important part of my question is whether or not gamma, Xradiation, Ultraviolet waves, Infared, neutrinos and other incidental electromagnetic spectrums all "travel" at the "speed of light". (?)

That's an easy one which even I, a layperson, am confident to answer. ALL EM travels at light speed in a vacuum, from the slowest to the highest frequency. No exceptions.

 

[TeV]

whether or not gamma, Xradiation, Ultraviolet waves, Infared, neutrinos and other incidental electromagnetic spectrums all "travel" at the "speed of light". (?)

Nutrinos are the part of electromagnetic spectrum?Since when?
Neglecting "neutrinos" in the package ;-):Electromagnetic waves all "travel" at the "speed of light" in vacuum regardless of their frequency.Great J.C.Maxwell concluded this first.

 

[RAD4921]

Motion is relative

All motion is relative to its frame of reference. To speak of absolute motion is meaningless.

 

[Les Sleeth]

All motion is relative to its frame of reference. To speak of absolute motion is meaningless.

In the situation of motion relative to its frame of reference, there are several distinct things present. There is a frame of reference, there is relativity, and there is motion. Looking at things analogously, just because a human being can't exist without space doesn't mean it's meaningless to contemplate a human being apart from space.

As far as I know, no one used the term "absolute motion." We are wondering what exactly motion is. Think about it . . . why should there be movement? What is causing movement? If we don't take motion for granted, to me anyway motion seems very strange.

 

[RAD4921]

Absolute motion

Motion can only appear if you are using a frame of reference, comparing one part of the universe to another. If you use the universe as a whole for a frame of reference then motion doesn't exist. It is an illusion.

 

[Les Sleeth]

Motion can only appear if you are using a frame of reference, comparing one part of the universe to another. If you use the universe as a whole for a frame of reference then motion doesn't exist. It is an illusion.

You might be correct, but I don't think that's what Namloh is getting at. (Of course, the universe itself moves as a whole -- as expansion. What is the whole universe moving in relation to?)

Namloh first asked "how can things even move?" I think this question is great because movement is something we just take for granted. There are some pecularities associated with movement. Theoretically at least there is an upper limit to speed of movement, and it produces relativity effects, especially accelerating movement. I think it is interesting that movement always involves entropy (overall anyway); since there is absolutely nothing that doesn't move, it is an indication about the fate of the universe (and maybe it's origin too). We speculate that at absolute zero there would be no movement, but we also believe absolute zero is impossible to attain. Did all movement begin with the big bang? Did some sort of movement precede the big bang and cause it?

One can see movement as a deep subject when one considers how things move in relation to consciousness. In China, ancient philosophers believed this, so much so that China's most enduring philosophy came to be one that developed principles dealing with change (movement is change). In that case, to achieve the desired results one ponders how to take action in accordance with current conditions, the flow of change, and known change principles.

Still, no one has answered Namloh's question of what movement is. We might know how it happens and what conditions are required, but we don't know why it happens.

 

[p-brane]

Nutrinos are the part of electromagnetic spectrum?Since when?
Neglecting "neutrinos" in the package ;-):Electromagnetic waves all "travel" at the "speed of light" in vacuum regardless of their frequency.Great J.C.Maxwell concluded this first.

Sorry and thank you. Neutrinos excluded.

However, if anyone knows the speed at which neutrinos travel; that would be interesting to know.

Quote from SelfAdjoint"From a spacetime viewpoint, those maneuvers are highly non-geodesic

Ah. I was imagining light waves and their dubious counterparts, the photons, traveling along the arc of one of Buckminster Fuller's geodesic domes and experiencing a "g-force" relative to their motion. Thus I mistakenly imagined that the photon could,topographically, be considered in its own time frame. I thought that time would exist for a photon traveling at c. But no!


Les Sleeth, Thanks for the confirmation on the speed of the light wave frequencies including Infared etc.

 

[Loren Booda]

We infer motion by feeling the vector boson (photon, graviton) action impingent upon us.

 

[Loren Booda]

Neutrino velocity varies near the speed of light according to its relativistic kinetic energy/momentum.

 

[Les Sleeth]

We infer motion by feeling the vector boson (photon, graviton) action impingent upon us.

Hi Loren, your input is interesting as usual.

To your response I want to say . . . maybe, but do you have an opinion about what causes the vector boson effect? I continue to see the answer to the question of what motion is as incredibly significant. Because we can explain the mechanics of something doesn't mean we've understood the causes of what is most immediately observable, or why it happens. In the case of motion, it is so key to every single aspect of our existence, I think it begs for deeper understanding.

 

[Loren Booda]

Right now it remains fundamental until something like superstrings manages to explain it with a more basic theory. I doubt we shall ever be truly satisfied with an explanation for something so intrinsic as motion.

 

[mikesvenson]

Without motion, there is no time. Without time, there is no motion, no cause and effect, no change. Motion 'causes effects'. Therefore, without motion, there is no cause and effect. So, then, is it still possible that motion has a 'cause' ?

 

[Les Sleeth]

Without motion, there is no time. Without time, there is no motion, no cause and effect, no change. Motion 'causes effects'. Therefore, without motion, there is no cause and effect. So, then, is it still possible that motion has a 'cause' ?

I wonder if it's necessarily so that without time there can be no motion. If time is considered the overall rate of entropy in our universe (i.e., the rate of its "passing"), I could imagine a situation where some sort of pure vibrancy was all that was left after the universe completely runs down. If that condition existed, there would be the motion of vibrancy, but since no entropic change would be taking place there wouldn't be time.

But it seems mainly you were saying motion itself is cause, and so is not itself caused. If that is what you meant, then motion would have to be inherent in the nature of reality, or a "given." Assuming that, then there still remains a tough question.

Since the universe does appear to be winding down, it means motion itself is changing and could mean its heading for some state of equilibrium. Assuming that ground state is where the motion we observe originates, then what caused that motion to be in the excited condition we see now? It doesn't seem ordinary motion alone can be its own cause.

 

[wuliheron]

Right now it remains fundamental until something like superstrings manages to explain it with a more basic theory. I doubt we shall ever be truly satisfied with an explanation for something so intrinsic as motion.

Oh, we might be satisfied eventually.

Einstein pointed out that space without time and mass without energy are quite meaningless terms, and functional contextualists have pointed out much the same thing. Physically, mentally, and linguistically it seems these terms are meaningless without reference to each other.

If a theory of everything is found that no other theory can replace for centuries, then eventually people will just accept it as the way things are, just as they used to believe the Earth was flat.

 

[p-brane]

Wuli: "Einstein pointed out that space without time and mass without energy are quite meaningless terms, and functional contextualists have pointed out much the same thing. Physically, mentally, and linguistically it seems these terms are meaningless without reference to each other. "

In a relativistic universe this holds true.

In a quantum universe motion is quite probably an illusion created by quantum excitation of homogenous and semihomogenous elements in various regions of a simultaniously existing field. The Cubists, Gertrude Stein, Braques, and Piccasso had an uncanny understanding of this illusionary phenomenon.

 

[p-brane]

And I use the term "regions" lightly. Moreover, that term could better be described by a wave theorist.

edit: The "illusion" of motion is caused by our inherent perspective and by our learned perception. These factors place us in a fixed and isolated position within a relativistic universe.

 

[wuliheron]

You are correct, motion could be illusory according to QM. However, this is not an explanation of motion, but rather, a lack of an explanation.

To say something is random, chaotic, or indeterminate is to assert that we cannot perceive any pattern. It is impossible to prove a negative, hence you can never prove the indeterminacy of QM, the best you can do is demonstrate that no explanation is necessary.

 

[p-brane]

To say something is random, chaotic, or indeterminate is to assert that we cannot perceive any pattern. It is impossible to prove a negative, hence you can never prove the indeterminacy of QM, the best you can do is demonstrate that no explanation is necessary.

On the contrary, QM is highly determinate. It has an intrinsic reliance on a synergistic state to exist. When a "motion" occurs in QM it is omnidirectional and in accordance with laws of realized potentials. It really requires a wave theorist's view.

 

[wuliheron]

On the contrary, QM is highly determinate. It has an intrinsic reliance on a synergistic state to exist. When a "motion" occurs in QM it is omnidirectional and in accordance with laws of realized potentials. It really requires a wave theorist's view.

Wave theory has not banished the Indeterminacy of QM. There are any number of self-consistent and nontrivial explanations for quantum weirdness, but none of them have proven to provide any better results than merely accepting the observational evidence that the motion of quanta are fundamentally random.

To assert otherwise is the height of hubris.

 

[p-brane]

Wave theory has not banished the Indeterminacy of QM. There are any number of self-consistent and nontrivial explanations for quantum weirdness, but none of them have proven to provide any better results than merely accepting the observational evidence that the motion of quanta are fundamentally random.

To assert otherwise is the height of hubris.

I assert that all motion is part of a chain of reactions to the initial action of the BB. It would be safe to assume that upon one's observation of a motion, quantum or otherwise, its vibratory frequency is essencial and integral to maintaining the balance of the existing overall field. Otherwise it would not happen.

Randomeity is an anthropomorphic construct created by the limited scope of observational powers excercised by most humans.