On Whether or Not Non-Gravitational Interaction Can Occur in the Absence of Gravity by Shawn Halayka

Copy and paste from Google Translate did not work good. :)

Induced Gravity in Superfluid 3He

http://arxiv.org/abs/cond-mat/9806010

Grigori very smart person

That's very cool Yuri. I've also heard about acoustic black holes / acoustic Hawking radiatiom.

- Shawn

Shawn,

Though you had no way of knowing it up front, you were destined to lose that one. Your views of information are simply different. Consider the exchange:

"I view meaningful information obtained from a physical message as a physical reality that leads to (possible) physical outcomes. [...] by contrast, the "info content" and the "data content" don't seem to lead to physical outcomes."

Unless one is claiming that particles attach "meaning" to information, then one is bringing consciousness into the picture, without of course, defining consciousness. Conscious interpretations provide the 'meaning' for information extracted from data, as I have argued in earlier comments. [I ignore here automated decoding-and-action systems that, in the end, trace to consciousness.]

The bottom line: "...information is physical..." As you noted, a lot of physicists seem to believe this. We can argue until we're blue in the face. I think it's a semi-religious thing based on naive materialism.

The problem: "...subjective experience is the entirely natural way that information is apprehended in the universe. Subjective experience is meaningful information."

Although we all have it, I don't believe 'subjective experience' was defined in that series of exchanges, so how can you argue with "information = undefined thing"? If someone cares to redefine information as "subjective experience" rather than use Claude Shannon's definition, there's no point in arguing. You can't win this one.

But I did find your arguments interesting.

Edwin Eugene Klingman

Hi Edwin,

I'm not debating the fact that information (entropy) is physical.

What's the information content of a single state? S = ln(1) = 0.

What's the information content of a single particle (think pre-relativistic quantum field theory)? S = ln(1) = 0.

What's the data content for either? Not zero.

No one debates this because it's obviously true. As for anyone who fails to recognize the difference between dsta and information content, they surely do not recognize that Shannon's entire theory relies on more than one distinct state (symbol) to produce information. This isn't some limitation of the log function -- it's how it really is. Information can only emerge from multiple, non-repetitive symbols.

Perhaps if you wish to swap "information content" with "ideal information content" and swap "data content" with "manifest information content", I can see your point of view, but in that world there is no room for the word data. I doubt that the people who study data compression would be obliging. They didn't call it "information compression" for good reason.

- Shawn

- Shawn

And for what it's worth, I'm being quite polite. The debate was about dishonesty (not my word), and I'm simply pointing out the dishonesty of those biologists and physicists who clearly did not thoroughly study pseudo-random number generation, graph theory, source coding (data compression, etc. I really have nothing against the people that I am debating with -- I gave them both quite high scores on their essays.

"pre-relativistic quantum field theory"

should have been

"pre-'relativistic quantum field theory'"

In spite of all that has been written about gravity over the years we still do not really know exactly just what gravity is. When it comes to motion we haven't a clue. Here is somewhat different approach to the subject of gravity.

Einstein, who, more than anyone else gave us our current view of the nature of gravity, said that gravity is not a force and yet in most of contemporary physics gravity is treated as if it were. It appears that the presently held view of gravity is that it does not pull you into the chair in which you are sitting but rather, because of the curvature of space-time, it pushes you into the chair. This is a bit absurd; Gravity is either a force or it isn't, it simply can't be both.

Einstein used the example of a man jumping from a building. The man would feel no force pushing or pulling him. The only way he would know he is moving is by the motion of the building that seems to be moving up and the friction of the wind. While nobody challenges this it seems to be almost universally ignored. The example of the man falling is a good one but gravity can be proved to not be a force by use of a very simple, basic physical law.

Suppose I hold a ball of a given weight stationary in the air. The understanding of vectors tells us that a force equal to the force I am supplying must be pushing down on the ball. Vector analysis also tells us that a resulting vector will appear in a direction opposite the acute angle formed by the two vectors. The acceleration of the resultant vector, if the forces are constant, is dependent upon the sine of the acute angle formed by the two vectors. In the case of my holding the ball the angle formed by my pushing up and the alleged force of gravity pushing down is 180°. The sine of 180° is zero so the resultant vector is zero. It is important to remember that the force and acceleration of both vectors is still very real.

Newton's second law of motion says that Force is equal to Mass times Acceleration - F=ma. If I hold a ball ten times heavier the force I supply must be ten times stronger as well. In order to the stationary position of the ball I must also increase the downward force ten times. Herein lies the problem.

Acceleration is dependent on force and mass. The only way acceleration can be changed is to alter either the force or the mass. We know that acceleration in a gravitational field is a constant. On the earth it is 32 feet per second squared. If the gravity of the earth is a force and created by the curvature of space-time then this force too must be constant. The only thing that is a variable is the mass however, if we change the mass we change either the force or the acceleration. Thus either heavier objects fall more slowly than lighter objects or the acceleration changes as a result of the change in mass. We know empirically that this cannot be true as both force and acceleration are constant. Therefore gravity cannot be a force.

The ball is now ten times heavier and thus the gravitational field (if indeed that is the correct term) is ten times as strong. The curvature of the space-time created by the ball is greater and so, if gravity is a force, the ball is pulling the earth with a stronger force. Actually the acceleration of the earth toward the ball has increased and so the earth is falling toward the ball at a greater velocity. We can see this in Newton's other formula: F = G(m1m2/r2) While this does not exactly hold in GR it is sufficient for this argument. The increase in the apparent attraction of the earth and the ten pound ball is so small as to be virtually immeasurable.

If gravity is not a force why do we feel our weight when sitting in a chair? Consider a situation where two opposing vectors are both forces, such as two cue sticks pushing on a billiard ball at two points in direct opposition.

The change in the position of the ball is zero and we can state that this is the resultant force of the two primary vectors. We have the mass of the cue ball and the force applied by the cue sticks. This means that there is in both cases an acceleration. An object can have any number of independent motions and in this case the ball is moving in two directly opposite directions but the ball is moving. The second law of motion states that force and mass will produce an acceleration. These two opposing accelerations do not 'cancel each other'. They create a vector with zero acceleration. Perhaps it may be more correct to say that they produce no vector.

Since gravity behaves much like a force, we feel our weight in a chair because we are still falling. Just because the chair stops a change in position does not mean we are not still falling. Our feeling of weight comes from momentum. A falling body has a certain momentum even if it does not actually change its position. It is this momentum we feel when sitting in a chair.

Since gravity is not in any way a force it has none of the properties of a force. It does not propagate. It would only propagate if it were a force. Contemporary physics not only thinks of gravity as a force but appears to think of it as an electromagnetic force. Many, many hours have been spent by really brilliant people trying to reconcile the 'force' of gravity with such forces as magnetism. The mass of an atom does not create the curvature of space-time any more than the nucleus creates the electron. The curvature is an integral part of the atom that was created when the atom was created. It cannot be modified nor removed.

Newton, when he worked out his gravitation theories, was concerned with action at a distance. Even though gravity is ubiquitous through the universe there is no action at a distance because there is no action. Gravity does not do anything, it simply is. It is not one of the elementary forces as it is not a force. There is no need for energy mediating bosons to mediate the force ergo, thus there is no graviton. I seriously doubt that the Large Hadron Collider will find any evidence of a massless, spin-2 boson.

It has been said that if the sun were to suddenly disappear we would not be aware of it for eight and a half minutes. That is true but has nothing to with the curvature of space-time and thus gravity. If the sun were to disappear instantly the curvature would disappear instantly as well. We would not sense this in any way, since the path of earth around the sun is a geodesic nothing would have changed; we would still be traveling in a straight line. Eight and a half minutes later everything would become instantly dark and start to quickly become very cold. That we would certainly sense and then we would know that the sun had disappeared.

The extent of a gravitational field appears to be limitless. It diminishes as described by the inverse square law but never completely disappears. Thus the entire universe is one large structure formed of a myriad of space-time curvatures.

Finally; since gravity is not a force why it is considered along with magnetism, the strong nuclear force and the weak nuclear force to be one of the primary force interactions of physical reality? Gravity is not a force, it is a condition.

If indeed gravity is not a force, are we correct is thinking that gravity functions at the quantum level? Does an elementary particle warp the space-time or is the concept of space even valid at the quantum level. It seems quite possible that gravity at quantum level may be a mathematical concept that would only be valid if gravity is a force.

It is intersting Mr Wagner,

You know, all spheres turn .The force of gravitation exists,it is evident.

They turn so they are Mr Wagner.in fact the gravitation is proportional with the rotations of spheres.Furthermore the system can be fractalized towards the quantum scale cosidering a cosmological sphere for example. It quantification is correlated.

ps the light and mass turn in opposite sense....see the comportment of the gravitation with the volumes of spheres, their finite serie and the finite number, the rotations spinal, the rot.orbital,the motion linear(hv)..... the evidence appears.:)

Regards

Hi Thomas,

First off, I'd like to say that I liked your essay a lot. I absolutely love music, but I did not know a single technical thing about it. I believe that I've learned a lot from the essay.

Secondly, I'm not entirely sure where you're coming from with the sine calculation that you're talking about. Could you elaborate further? Usually when I "do" Newtonian gravity, I do something like

- Get the vector pointing from my position to the gravitational source position:

[math]\vec{D} = P_{\textrm{src}} - P_{\textrm{me}}[/math]

- Get the distance:

[math]r = length(\vec{D})[/math]

- Normalize D (this step can be avoided if you really must, but should be compensated for later):

[math]\hat{D} = \vec{D}/r[/math]

- Calculate the acceleration vector from the source mass M (divide by r^3 if you don't pre-normalize D):

[math]\vec{A} = \hat{D} GM/r^2[/math]

And then I just add the acceleration vector to my velocity vector. It's kind of sloppy, but it works.

As for what gravity really is... Yeah, I have no idea for sure, but I have read on the web somewhere that the shrinking of the orbits of binary stars over time is due to gravitational radiation, and that the rate at which the orbits shrink is definitely affected by the speed at which the gravitational radiation propagates. Here's the link: http://en.wikipedia.org/wiki/Speed_of_gravity#Possible_experimental_measurements

Likewise, according to this theory, if the Sun were to vanish then this would lead to a change in the metric of spacetime, and this change would propagate at whatever speed the gravitational radiation travels at because it's all effectively the same thing (a metric that is not constant in time).

Whether you buy into that is up to you, but most people are satisfied by it.

In any case, some people think that it's possible that gravity emerges from the electromagnetic/weak/strong interactions (ie. Sakharov, Jacobson, Verlinde), and so gravity is not a force per se. I like that idea, mostly because it simplifies the big picture. I'm not sure about the idea's validity though (I'm not an expert in anything, really).

Once again, thanks for sharing your essay. It's quite great.

- Shawn

Jedi,

Your powers are no match for the dark side. Just kidding. I've just wanted to say that for a while now. :)

- Shawn