What is Space?

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What is Space?
Posted by Odenwald on Thursday, November 28, 2013 6:59 AM
Imagine yourself sitting on a park bench. You watch as people stroll by on the path only a few feet away, and are amused by the children playing on jungle gyms a few dozen yards away. Your cellphone rings and it’s your friend calling from San Francisco, 4000 miles away. During the call you discuss a bit of world politics and wonder about the calamities befalling people located 12,000 miles from where you are sitting. You also chat about the latest results from NASA’s Curiosity Rover as it navigates a rock outcrop on Mars 120 million miles from Earth.  Yet, still you are sitting here on a park bench, which your cell phone GPS says is located at longitude 71o 7’ 18.34” West and latitude 42o 22’ 36.78” North on the surface of Earth. You can take out your tape measure and accurately measure the distance to a nearby tree. Then after you have finished your stay, you can make this same measurement over again and get the same answer. As you walk back to your apartment, you retrace the same geometric path through the streets and avenues of your city that led you to the park bench, and find yourself back where you started at your front door. The 1652 yards to get to the park bench, is exactly mirrored by the 1652 yards it takes you to return home by the same path. 
        None of the elements of this story have anything to do with the usual obsessions of physical science such as matter, energy, forces, and motion. They are all statements of geometry and distance within space. Not just any kind of space, but a particular kind that has exactly three dimensions (3-D) – no more and no less. So why is it that things like matter, energy, forces and motion play themselves out in an arena called space? Does space exist independently of its ingredients, like a theater stage to the actors upon it?
                  Unlike most things that can be directly experienced, it is difficult to think clearly about something you can neither touch nor see. For thousands of years humans have flirted with understanding space. Usually the dialogs have been rather silly by our modern standards because after all, what profound things can you possibly say about something that is completely intangible? But now it seems there are so many lose ends in 20th century physics that, once again, we are forced to have a closer look at this thing we call space. We seem to be at the threshold of this understanding today, but the shape of this understanding would give even an astronomer nightmares!  
            Theoretical physicists who write popular books about cutting ideas in physics invariably want to delve into the mathematical arcana of their own specialties because that is what they know the most about. The discussion moves quickly away from familiar ideas and hard data, into the exquisitely complex and mathematical arena of quantum gravity theory with its unobservable strings, branes, spacetime foam and quantized fields. Without any firm evidence that Nature uses these exciting and at times beautiful mathematical constructs to describe space, you and I are left with an intuitively confused explanation for space and its properties with few anchors into the real world of atoms, people and planets. For example, with almost no exceptions, physicists have few data to present to you about black hole physics. One very popular physicist is a world-renowned expert in cosmology, quantum gravity and black hole physics, however, not a single one of his ideas has been experimentally proven with actual data. The Nobel Laureate Sheldon Glashow despised string theory and its 10-dimensional world because it could never be subjected to realistic tests. Similarly, Nobel Laureate Richard Feynman, who almost single handedly invented Quantum Electrodynamics, also had enormous trouble with the new generations of physicists. “I don’t like it that they are not calculating anything…or checking their ideas [against hard data]”.
        These are not philosophical quibbles, nor signs of jealousy within the physics and astronomy communities levied against the theoreticians who always seem to have engaging stories to tell that captivate the imagination. Instead, they are the most basic ideas that confront anyone who wants a clear-headed answer to questions based on what the real world is actually doing. We are not just looking for a good story that can only be falsified by an appeal to logical consistency or a call to mathematical ‘beauty and elegance’. We are looking for that particular good story that can be proven almost literally by a scientist working at the lab bench.
        My recent ebook 'Mind, Space and Cosmos:Exploring the mystery of space and how we think about it' will show you the many possible ways to think about space that have been tried, including string theory, loop quantum gravity and many other ideas using over 130 illustrations.  (http://tinyurl.com/kqxbuef)
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Posted by Primordial on Saturday, December 07, 2013 10:34 AM

Odenwald : Very well stated, this will appear to add to your understanding, or in some cases to your confusion, but the observed is but one part of an implicit equation and the other is the observer, so what you observe, is what reality becomes. Just think about it.

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Posted by Bullfox on Saturday, December 07, 2013 12:29 PM

If it were not for space time everything would be hapening all at once at the same place which would be very confusing.  Space time,regardless of mathmatics, provides a rubbery stage on which we all may supply our own vision of reality.  Very democratic

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Posted by Primordial on Sunday, December 08, 2013 11:41 AM

Bullfox : Well stated, Mr. Einstein put in relativistic perspective as a fabric. It's an arena where energy within which all of its tricks are played out relative to all observers. I like the stage, it provides the energy.

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Posted by archimedes on Sunday, December 15, 2013 1:45 AM

Sten,

As far as I can gather, your book is only available in Kindle format.

For those of us who don't have a Kindle, is the book available in any other format, PDF, hard copy, etc?

Regards,

A.

PS:  It's OK, I've just noticed that it is possible to get a free Kindle reading app. from Amazon.

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Posted by Antitax on Sunday, December 15, 2013 6:47 AM

   A few physicists like Jacques Vallée reduce everything to information, and call themselves information physicists. They nearly deny time as a dimension if I recall well, and simplify reality to only the three dimensions we can experience directly or represent in our mind. That's quite a relief because no one could ever picture the fourth dimension in their mind's eye.

   Another simplification is reducing forces and matter and energy to information and information flow. In this case (with the caveat that I remember well enough), things are like clouds of information in the Net, and interact by exchanging information. The Earth attracts the apple because they exchanged information along the line of: "Hey, apple, I'm a big mass and you're a small mass, so get closer to me a lot, and I'll get closer to you a tiny little". And the apple answers back: "I received you message and I agree, let's get closer".

   The distance between them is only information that conscious beings picture in their mind as separation, but really, whether the distance is an apparently small millimeter or an apparently large light-year, it's only a number or concept that occupies the same "space in the computer's memory", no matter how large or small the pictured separation seems to be in the mind's eye.

   Thus everything exists at the same place and simultaneously (meaning time is static or non-existent), conscious beings only pick information (usually a very small part of what is available, more evolved minds could pick more), and translate it within their mind's eye as events, distances, or places or energy, matter, whatnot.

   Like all the knowledge exists at once in the Internet, but individual computers can only display a narrow part of it. A more powerful computer (a more evolved mind) can handle more information, and the whole of the information is the whole Universe of the Internet.

   And like the Net affords to see videos of the past, or play them in reverse, or faster or slower, a mind can travel through the information in any direction and appear to betray the usual flow of time. And things can change shape instantly; the mouse's pointer can go from an arrow to a hand but that's no magic, only the info that the pointer is at a certain place can be displayed as a shape or another, and be modified endlessly. Doesn't matter, it's the same pointer at the same place, but with different display information attached to it.

   Three concrete dimensions, everything reduced to info, no messing with a fourth dimension no one can grasp; I like the simplification this theory proposes.

   A cousin theory says the observers of this (the conscious minds) are made up of particles of consciousness. A single particle of consciousness does very basic things such as changing the behavior of a wave/matter particle compound according to circumstances. Like in the famous fundamental experiment of quantum physics in which an electron behaves as particle or a wave depending on whether the attention of an observer is on it.

   If everything is made either of information or consciousness (something able to read or process or change information) there's no wonder things can be influenced by the mind and that's no witchcraft.

   (As a sidenote, I know a famous musician and music teacher with 25+ years of experience who says generic time does not exist, everyone creates their own time when they start a beat. He reached the same conclusion as some physicists or philosophers, but from another venue).

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Posted by Antitax on Sunday, December 15, 2013 9:11 AM

   To get back to the original question of what space is, in this theory, or set of theories, space and everything it contains is the data inside the computer. And the computer screen is the observer's mind's eye where raw data is displayed in various ways: shapes, colors, motions, appearances, disappearances, changes, distances, blackness, light, whatever.

   Very much like the classical greek philosophers who thought all is math, or what this guy thinks:

http://www.youtube.com/watch?v=X2-Y18hLRL4

http://www.youtube.com/watch?v=X8l9AprftVw

 

Tags: quantum mind

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Posted by Primordial on Sunday, December 15, 2013 12:59 PM

Antitax : Vey good, thanks for the link. Just my opinion.

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Posted by archimedes on Wednesday, January 22, 2014 4:03 AM
Sten,
Thanks for bringing your book to our attention.
I enjoyed the book for its many historical references and detailed explanations. I think that for the most part it sums up pretty well both the extent and the limits of our current understanding of space and time.
Like most books on this subject, however, it stands out as much for what it doesn’t tell us as for what it does tell us.
In particular, it does not to tell us what space and time are; why space and time exist in the first place, and why there is something rather than nothing. To the contrary, the book seems to be saying that space and time are beyond our present understanding, considering especially that even the experts disagree on the nature of space and time.
And so the general impression I get from reading this book is that physicists as a whole are confused on what is, or is not, the nature of space time—it seems we cannot even agree whether space and time have material existence, like atoms, or whether space and time exists only in our minds in the abstract sense of a mathematical concept, like imaginary grid lines on an imaginary sheet of paper.
And if, as some people have contended, the only reality is the reality of what is apparent to our senses, or can be measured by our instruments, which in the paradigm of modern physics consists of the material particles that are presumed to make up the visible components of the universe, then what need do we have for abstract concepts like space and time other than as convenient reference markers in our mathematical models which describe how those particles interact with each other?
Advanced concepts like strings, loops, branes, higher dimensions, and the like, merely add to the confusion, or add to the richness of our understanding, depending upon your point of view.
But if scientists cannot explain the nature of space and time in simple terms how on earth can the rest of us be expected to understand the nature of space and time in terms of such esoteric concepts as those I briefly mentioned above--concepts that  hardly anyone, I would think, with the possible exception of a select few, can understand?
For all the wealth of information and reasoned argument contained in this book, I think that more emphasis could have been made in the book with regard to the link between finite physical space-time and infinite abstract space, which some people associate with the so-called "vacuum of space". In particular, some mention of the role of the uncertainty principle of quantum mechanics could have profitably been made in this regard, I think.
In many situations we find it convenient to think of physical space as being somehow synonymous with empty space, for physical space is curiously resistant to our attempts to probe it. As pointed out in the book, we cannot weigh it, nor can we measure it without reference to material objects, so that in fact we can never measure space directly.
And when we do measure space, albeit indirectly, we invariably find that our measurements depend on our choice of reference frame.
And if I choose a reference frame which is different from yours then almost certainly my measurement of space will differ from yours.
Much the same can be said for time.
As Einstein frequently pointed out, any physical definition we may propose for time essentially can be reduced to something like: if the big hand on my watch points to 12 and the little hand points to 7 then the time by my reckoning is 7 o’clock.
And as Einstein further pointed out, there is no guarantee that my watch will agree with your watch, for the subjective measure of time for any observer is totally dependent on the reference frame of the observer.
But if space were completely empty—if physical space were precisely equivalent to the abstract notion of a perfect vacuum, or void—then arguably the measurement of space should be independent of choice of reference frame.
So, what distinguishes physical space from abstract space or, in other words, from the theoretical, perfect vacuum?
And why should time appear to us to be so different from space in our everyday experiences and yet, according to theory, as a dimension of space-time, time is on an equal footing with space? How can time be equal to space and yet be different at the same time?
Another question: is it possible that physical space and physical time (presumably along with matter), as some people have argued, somehow emerged out of nothing?
Surely, if physical space and physical time emerged from nothing, as has been argued, then the equations of general relativity and quantum theory in particular, should be able to explain how and why this occurred?
But as far as I know, no one has come up with a straightforward explanation.
Nevertheless, an inner voice tells me that there must be a definite, if as yet undefined mathematical explanation of how the physical universe, which includes space-time on the one hand, and matter on the other, emerged from nothing at all.
Otherwise the very existence of the universe, to my mind, would constitute a contradiction.
That same voice tells me, also, that the answer to that last question, or at least a partial answer, might be found in the uncertainty principle of quantum mechanics.
Yet, as far as I can tell, no mention of the uncertainty principle can be found anywhere in the book, which I think is an unfortunate omission.
Another question which comes to mind when reading the book is: how does one explain the motion of material objects through physical space in the modern context of general relativity and quantum theory.
You might think this is a trivial question, but consider how the concept of notion has changed through the history of natural philosophy.
In ancient times, well before Newton, some philosophers (such as Aristotle) taught that the natural state of a body is one of absolute rest, and that all motion requires the continuous application of force.
According to that teaching, as I understand it, when I throw a stone into the air the force of my hand imparts an initial motion to that stone. But once the stone leaves my hand the force of my hand no longer acts on the stone. And so, in the absence of a sustained force, the stone should, one might expect, immediately come to rest because that is the natural state of the object.
But of course, that does not normally happen for, invariably, the stone will continue to move some distance through the air before it reaches the ground.
Therefore, in order to explain the continued motion of the stone in the context of the Aristotelian teaching, one needs to suppose that a force is continuously acting on that stone. Perhaps, for example, some of the air in front of the stone has been displaced by the stone due to the motion imparted to the stone by my hand, and this causes the air behind the stone to push the stone a little further, which displaces more air in front of the stone, and so one, whereby the stone continues to move some distance.
We see here a similarity or analogy, if you will, between the Aristotelian concept of motion and the pre-quantum mechanical concept of propagation of waves, for both required the presence of a physical medium.
The big problem with the Aristotelian concept of motion is that we know from observing the motions of stars and planets that objects move through empty space without apparent drag by, or any need for an intermediary of, a material medium such as air. Indeed, air or other material would merely hinder the motions rather than reinforce them.
Newton dispelled the Aristotelian explanation for motion of material objects, excluding the motions of waves, by postulating his three laws of motion, the first of which, and the most relevant to this discussion, being the law of motion which states that every material body has a property called inertia—which is that property of tendency of a body in a state of rest or in a state of uniform motion, to continue in that state unless acted upon by some external force.
So, whereas, Aristotle imagined that a force is needed to maintain uniform motion, Newton showed that force is not needed to maintain uniform motion (in the absence of friction etc.) but only to change motion.
Because Newton’s first law of motion appears to have beeen verified time and again to a remarkably high degree of precision by various observations, such as the motions of the planets, we tend to take for granted that the property of inertia is constant and intrinsic to every material body. [By ‘intrinsic’ property I mean a property that does not depend on external influences, in contrast to an extrinsic property which does depend on exernal influences.]
We know, incidentally, from the Michelson Morley experiments of the late 1890’s – early 20th century, that electromagnetic waves do not need a material medium (in the classical sense) for the propagation of such waves.
Could there be a connection here between the fact that electromagnetic waves can propagate through empty space, apparently without the intermediary of a physical medium, and the fact that matter can move, apparently unhindered through the same empty space?
Could that connection be inertia?
The notion that electromagnetic waves in particular, and particles of matter in general, can move apparently unhindered through empty space would seem to suggest that inertia is an intrinsic property of matter (and incidentally of electromagnetic waves—or photons, if you prefer).
 To some extent, I think, the notion that inertia, like gravitational mass, electrical charge, etc. is an intrinsic property of matter is part of the reason for the confusion many people seem to have as to the nature of space-time.
For, taken on face value, if inertia is strictly an intrinsic property of any material body, then the motion of that body moving freely through empty space should, I would think, be unaffected  by the motions of other bodies also moving freely through space.
But that, as we now know, is not right because Einstein showed that every material body affects every other material body by virtue of its gravitational influence.
Furthermore, gravity is interpreted in Einstein’s general theory of relativity, to be a curving, or bending of space-time. That bending of space-time would seem to imply that there can be no such thing as perfectly uniform motion in a universe containing matter, because gravity, we presume, affects the motions of all material objects in the universe, hence the motion of any one such body in the universe is affected by the motions of every other such body in the universe, and vice versa.
The general inference, as I see it, is that the property of inertia must be an extrinsic property of matter (meaning here specifically that the inertia of every material body in the universe depends upon the inertia of evey other material body in the universe).
The fact that the mass of a body affects the geometry of space-time implies also, in my mind, that inertia is an extrinsic property of space-time as well, because the only way that I think of to explain the gravitational influence of one material body on the motion of another via the geometry of space-time is through a transfer of inertia from one body to the other via the intermediary of space-time.
In concluding, I would just like to say that I consider this book a useful and welcome addition to my library and I would recommend this book to anyone who wants to broaden his or her understanding of the nature of space and time.
Regards,
A.
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Posted by Primordial on Friday, January 24, 2014 12:35 PM

Archimedes : Not trying to butt in, but I'm butting in. I like the points you make in this subject. Just an opinion.

I've tried to reduce space-time to if fundamentals, and came to this point, energy + vacuum ( nothing ) + information. In this idea, energy contains information, which allows entropy ( time ) distribution of information, vacuum, which supplies a limiting condition ( localization ) for the interaction of energy and information through what we term as the interactions. It sort of remindes me of an old question " What would be the result of the interaction of an im-movable substance and an ir-resistable force, " Just making conversation.

Cheers....Primordial.....

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Posted by archimedes on Saturday, January 25, 2014 4:59 AM
Primordial:
I do not in the least consider your contribution to this thread to be butting in; rather I welcome it, for isn’t that what a forum is for—to introduce and/or discuss ideas?
Like you I have tried (in my mind) to reduce space ands time to fundamentals, but time and again have been frustrated in all my attempts at doing so.
Despite my personal failures in this regard, my gut feeling is that the true explanation for space-time, when so reduced, should be easy to understand for if it were not easy to understand then it could not have been reduced to fundamentals, and then, I think, we would have a contradiction of terms.
Think of a computer program, for example: the most complex computer program can (usually) be reduced to a sequence of a small number of basic computer instructions.
Or take the most complex organic molecule you can think of: such a molecule I am sure, no matter how complex, can be reduced to an arrangement of just a few basic elements—carbon, hydrogen, oxygen, and so on.
I recall reading an essay some time ago by Charles Darwin, not the Charles Darwin who wrote “On The Origin of Species” but a descendent of the same—Charles Darwin the physicist who worked with Earnest Rutherford on radioactivity in the early 1900’s—who remarked in his essay on the contribution of another physicist, H. G. (Henry) Mosely, who also worked with Rutherford at the time.
Mosely is probably best known today for having proved the now well-known relation between atomic number (the nuclear charge) and position of the elements in the Periodic Table.
From memory, Darwin wrote, in regard to Mosely’s work, something to the effect that often great discoveries in science are “easy” not in the sense that the discoveries were easy to make but rather, once made, were easy to understand. That was certainly true in the case of Mosely’s “discovery” of atomic number, for it was not at all obvious at the time that the position of an element in the Periodic Table was determined by its nuclear charge (most physicists thought that the position of an element in the table was determined by its atomic weight, which is not the same thing at all).
And though it may have been obvious to Mosley that it must be so, proving it to be so was not at all easy. And once he proved that relation, nearly everyone was able to understand the relation: what it meant and why it was so.
I think there is something very close to an analogy between the situation regarding the state of knowledge as to the fundamental nature of atoms, in the early days, and the current state of knowledge as to the fundamental nature of space-time.
But I think also that once somebody manages to explain the true nature of space-time in fundamental terms, then it should be relatively easy for every one to understand it.
And that is one reason why I like your approach to the problem, because I think it is only by reducing space-time to its fundamentals that can we hope to understand it.
Thank you for your thoughts.
Regards,
A.
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Posted by Bullfox on Saturday, January 25, 2014 2:52 PM

Gentlemen,

I have tried to get a mental handle on space time by imagining a space time completely devoid of everything then puting things back into it one at a time to see what it might be like.  Not much help. Then tried to take things out of our universe one at a time to see what it might be like.  Again not much help.  Then I tried to imagine what it would be like if mass had no inertia.  This was just silly as it seemed to make everything whiz around at break neck speed, acceleration being instantanious.  None of this mental effort lead to much.  The only conclusions I came were that the uncertainty principle is fundimental to everything and that there might be a completely empty space time somewhere and some when, but not much goes on there, and in any event, its not the space time we inhabit.

Bullfox

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Posted by Primordial on Tuesday, January 28, 2014 9:44 AM

Mr. Bullfox : I've looked through your presentation, it appears to me, inertia and gravity along with vacuum are the essential components. According to Mr. Mach, inertia is the result of gravity, also Mr. Einstein defined inertia as the configuration of relativistic space-time ( a geodesic configured frabic relative to each observer.) . Thank you for the insight. 

Consider this, If the universe started from a singularity, can we assume this to be an absolute location relative to all space-time at the instant of the initial big bang (?), If yes, and all space-time expanded from this position, then could we assume this position to be the origin of all reference systems at the micro-position in space-time, similar to the Planck space-time of each observer (?), or what we might refer to as our relativistic energy state or inertial position. Just think about it.

P.S. Every observer must exist somewhere and some energy. Just think about it.

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Posted by Bullfox on Tuesday, January 28, 2014 1:34 PM

Mr. Primordial,

A completely empty space time cannot be observed, but is not necessarily hypothetical.  If I had a completely empty space time and put one photon in it the photon has no where or when.  Furthermore. in what sense can it be said to be traveling at the speed of light?  If I put in a proton instead of the photon what effect will the proton's mass have on the space time?  Would it, containing no other mass, curl up around the proton?  Also, I have begun to think that inertia may be more basic than mass.  Are mass and gravity emergent aspects of inertia?

Lastly, in my previous post I stated that the uncertainty principle is basic to all reality.  At the time that was more of a hunch than a conclusion.  Since then I have been trying to come up with a chain of reasoning leading to that possible conclusion, but with no success.

Bullfox

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Posted by Primordial on Tuesday, January 28, 2014 2:26 PM

Mr. Bullfox : I like your approach, let me add this, I know Mr. Einstein's theory as interpreted by Mr. Desitter had an effect of mass on space-time dynamics, but Mr. Einstein used gravity as he understood it to be, at that time.

The reasoning of garvity being associated with mass only may lie in the entropy of its basic components and thier location relative to the Planck interval, which may have the responsibility of the big bang. Think of it like this, with out information, energy has the same meaning as a photon without an observer observation gives the photon meaning without  it, it is just a probability wave with out meaning provided by an observer of mass, which has a reference to the Planck interval. As energy is exchanged, information of the reference systems propagate through space-time ( its theater of entropy). The Planck interval is the source of uncertainty and the initial big bang source. This scenario is difficult to put into words so it may take reading several times. This is just my opinion.

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Posted by archimedes on Monday, February 03, 2014 8:33 PM
Is “the uncertainty principle basic to all reality”?
 The uncertainty principle says, among other things, that one cannot (simultaneously) measure precisely both energy and time. It also says one cannot (simultaneously) measure both momentum and position.
Some people might say: “So what! The universe might look different  from what it does now if it were not for the uncertainty principle, but what has that to do with reality?”
Let’s consider some basics.
On the one hand we have the ‘tangible’ stuff of the universe, which we call “matter” and on the other hand we have the ‘intangible’ stuff of the universe, which we call “space”, or “space-time”, if you prefer.
Let us assume that it is possible for matter to exist independently of space-time and vice-versa.
Since matter, we say, is tangible we can ascribe tangible properties to matter, such as energy and momentum.
But since space-time, we say, is intangible we cannot ascribe such properties to space-time.
Is this reasonable?
Well then, if space-time is intangible then it would be pointless to try to measure, for example, the energy of space-time, for how can you measure the energy of something that is intangible?
Or how can you measure the momentum of something that is intangible?
Nevertheless, according to the uncertainty principle, if we did try to measure the energy of space-time we should find that the energy is not zero!
And if we tried to measure the momentum of space-time we should find that the momentum is not zero!
How can that be?
The answer is that zero is a precise value, and therefore, the energy of space-time at some particular point in time cannot be zero.
Likewise, the momentum of space time cannot be precisely zero at some precise position in space..
So what the uncertainty principle says, in effect, is that there can be no such thing as a truly empty space-time.
The implications of the uncertainty principle extend far beyond the mere question of determinacy of properties like energy and momentum, for they go right to the heart of the question of what constitute matter and space-time.
The importance of the uncertainty principle in this connection stems  from the predictive power of the uncertainty principle.
For example, the uncertainty principle predicts the existence of “virtual” particles, which are thought to be constantly popping in and out of the so-called “vacuum” of empty space.
Virtual particles resemble real particles in practically every respect except that they have such extremely short lifetimes that they (apparently) can never be observed directly.
So what, some people might say!
Well, for one thing, the virtual particles are thought to be the carriers of the fundamental forces between real particles namely, the electromagnetic, strong, weak and gravitational forces, respectively.
For example, a virtual photon is thought to be the carrier of the electromagnetic force and a gluon is thought to be the carrier of the strong force.
And though no one seems to be quite sure what virtual particle is the carrier of the gravitational force, almost certainly there must be such a particle.
Imagine what the universe might look like if there were no forces.
Then there would be no such thing as “motion” in the usual sense of the word.
Why?
Because the only way we have of defining motion is in terms of relationships between material bodies.
If there were no forces between particles of matter then there would be nothing to relate the state of one particle relative to another. And therefore there would be no way of measuring things like distances and times.
There could, in that case, be no such thing as motion through space because space itself would be undefined--it simply would not exist as we know it.
The question you might now ask is: could matter exist if space-time did not exist, or vice versa?
Well, the uncertainty principle predicts the existence of virtual particles, so presumably the uncertainty principle is fundamental to the existence of virtual particles.
As for real particles, apart from the fact that real particles have much longer lifetimes than virtual particles, there is really very little, in principle, to distinguish between real particles and virtual particles.
Even so, how can we know for sure whether, or not, the uncertainty principle is fundamental to the existence of real particles as well as virtual particles?
In trying to answer that question, let’s assume that the uncertainty principle is at least fundamental to the existence of virtual particles.
It is an observable fact that we cannot “see”  virtual particles in the way  that we see real particles. A table or a chair, for example, is obviously made of real particles, not virtual particles. The coffee I had at breakfast is made from real particles.
The reason why we do not see virtual particles as we see real particles, in part, is because virtual particles as a rule have much shorter lifetimes than do real particles.
We could, I suppose, define a virtual particle to be any particle which has a lifetime shorter than some arbitrary time which is shorter than can be measured directly.
Another part of the reason why we do not see virtual particles like we see real particles is that some (about half) of the virtual particles have negative energies. This means that these particles not interact with real particles in the same way as real particles interact with other real particles.
For example, a positive energy electron interacts with a positive energy positron (a positively charged anti-electron) by a process in which the total mass-energy of these particles is converted into pure (massless) energy. So what we see in this case is the particles vanish (as such) in a burst of radiation (a pair of photons). Since the positron is the antiparticle of the electron, total charge, spin etc. are conserved. Energy and momentum also are conserved, which is why we see a burst of radiation rather than total annihilation (into nothingness).
By contrast, when a positive energy electron interacts with a negative energy anti-electron, provided that the energies and momentum are equal in magnitude, the electron simply vanishes into nothingness; no flash of light, no puff of smoke, nothing to indicate that the electron ever existed.
As before, energy, momentum, spin, etc. are conserved but because total energy and total momentum are zero annihilation in this case is total.
You might be wondering at this point, what makes some particles real and some particles virtual? Why aren't all particles real, or why aren't all particles virtual?
To gain some understanding of why that is so, imagine that you are travelling in a space ship through (seemingly) empty space.
Let us suppose, for the moment that, although the space ship has an engine, the engine, for the present is turned off.
And so, according to Newton’s first law of motion, the space ship is drifting through space at uniform velocity, that is to say, without acceleration.
As you might expect, from your vantage point in this freely-floating spaceship, space appears to  essentially empty (despite the presumed presence everywhere in space of virtual particles galore).
But suppose you turn the engine on and set it to full blast.
Suddenly see a glow in front of you as though half the sky were lighting up.
This glow, you find, consists not only of photons (particles of light) but particles of all kinds, such as electrons, neutrinoes, protons etc.
[I hasten to add that you would have to be accelerating at a truly tremendous to see the more energetic particles in this radiation, for the effect in question is very, very weak, at ordinary rates of acceleration).
The effect you would be seeing is called the Unruh Effect. It is an effect which results purely from acceleration. 
[Note that a non-accelerating observer would not observe the particles due to the Unruh Effect; in that sense particles which appear real to one observer need not necessarily appear  real to another.]
In effect, the fact that you are seeing these particles means that, from your perspective, there is an excess of positive energy (virtual) particles over negative energy (virtual) particles, because if there were an equal number of both kinds of particles the net energy would be zero and you would not be seeing any particles at all.
Therefore, some of the virtual particles which previously were invisible to you now have become visible because of your acceleration.
But acceleration, as Einstein pointed out, is equivalent to gravity.
Therefore you could say that the particles which previously were virtual particles, have become real by virtue of the gravitational field generated by your acceleration.
Can you see the similarity here between the radiation resulting from the Unruh effect and another effect: black hole (Hawking) radiation?
Black hole radiation is caused by the gravitational acceleration of virtual particles near the event horizon of a black hole, which causes some of the virtual particles in that region to become real.
In that sense  black hole radiation and the radiation resulting from the Unruh effect are analogous.
All of which bring me to the point that I am trying to make here.
We live in a universe which is dominated by matter. Matter has mass and therefore it has gravity.
And gravity, as we have just seen, causes virtual particles to become real.
Can gravity exist without matter?
Evidently not!
Can matter as we know it exist without space-time?
No because space-time is intimately related to gravity and matter cannot exist independently of gravity.
So put together the uncertainty principle and gravity and what have we got?
What we have got is this:
We started out with the uncertainty principle which predicts the existence of virtual particles.
We have seen that the virtual particles are the carriers of the fundamental forces. One of those is the gravitational force.
We have seen that the gravitational force turns virtual particles into real particles.
We have seen that the forces allow us to define relationships between the real particles.
We have seen that the relationships between the real particles allow us to define space and time; in effect space and time derive from those relationships.
And finally, those relationships are expressed in the uncertainty principle, which is what we started off with.
And so we come full circle, starting off with the uncertainty principle and ending with the uncertainty principle.
Would you say that the uncertainty principle is fundamental to reality?
I think I would.
Cheers.
A.
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    August, 2007
Posted by Primordial on Tuesday, February 04, 2014 12:46 PM

Archimedes : Excellent. I'll keep.

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    May, 2007
Posted by Bullfox on Friday, February 07, 2014 10:49 PM

Archimedes,

Thank you for your thought provoking exposition of the uncertainty principle. It made me wonder if our perception of the particle/wave diluality of matter is grounded somehow in the uncertainty principle.

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Posted by Primordial on Sunday, February 09, 2014 11:25 AM

Mr. Bullfox and Archimedes : This is just to continue this discussion, I think we are viewing space and not space-time, If we view space-time and include the difference in energy states ( of which entropy takes a relative position ), and the difference in relativistic space-time and proper space-time, we find a completely different subject. As you may remember the twin paradox and how entropy played its part.

I like to picture black holes as if they exist far into our space-time past ( With an emphasis on the time relative and time proper aspect.) due to the space-time contraction difference between two energy states.

Picture it like this, let us assume the black hole is frozen in the one spatial dimension  (which Relativity points out, in Special Relativity)  it would make the black hole a two spatial dimensional object with the time dimension remaining constant. Although the black hole may not be moving relative to our platform in space, it is moving in time at a much different rate, so it in one way of viewing, is far away in a different aspect of space-time. Just think about it. 

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Posted by archimedes on Sunday, February 09, 2014 5:48 PM
Bullfox:
I would agree that wave/particle duality is grounded in the uncertainty principle.
The uncertainty principle is derived from the Schrodinger wave equation.
That equation incorporates, in addition to the law of conservation of energy, Einstein’s hypothesis that light has particle-like properties as well as wave-like properties and de Broglie’s hypothesis that particles, such as electrons, have wave-like properties as well as particle-like properties.
The uncertainty principle is frequently expressed in the form
ΔE Δt ℏ / 2,
where ΔE is uncertainty in energy, Δt is uncertainty in time and ℏ is Planck’s constant.
Or, equivalently,
Δp Δx ℏ / 2,
where p is the uncertainty in momentum and x is the uncertainty in position.
We can think of time in this context as being the inverse of frequency, which is a wave-like property (note that the properties of classical particles are not dependent upon time).
And we can think  of length, in this context, as the equivelent of a wavelength, which also is a wave-like property.
Energy and momentum, on the other hand, are properties of both waves and particles.
Put energy and time together, or momentum and space together and what you get is a property of matter, called "action", denoted by Planck's constant.
In other words,  any property that can be expressed in units of action, is always measured to occur in discrete multiples of   or  ℏ / 2.
Quantization of any property is suggestive of particle-like behaviour.
So, I think it is reasonableto conclude, based on the uncertainty principle, that  any entity which has energy must have both wave-like and particle-like properties.
Primordial:
I think that the properties of space and time derive from the properties of matter and therefore a description of space and time is essentially a description of the relation between particles (of matter).
If the universe were static then you could, I suppose, argue that space is fundamental (to that relation) and time is secondary.
But the universe is not static and so I think that to fully describe the relation between the particles we need to include time as well as space.
However, I think I see what you are getting at.
To an approximation, we see our ‘local’ region of the universe as being essentially static.
Relativistic effects tend to become evident only when events that we are observing are occurring in frames moving near the speed of light relative to us, or are occurring in regions of an intense gravitational field far removed from our own.
And the point you made regarding a black hole is a good one.  
Thus a hypothetical observer inside a black hole, for example, would have no awareness of events occur outside of the black hole, and vice versa.
Thanks for your thoughts.
Regards,
A.
PS: the following link (unrelated to this topic) may be of interest:
  • Member since
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Posted by Primordial on Tuesday, February 11, 2014 12:42 PM

Archimedes : I like your this explanation of the position which time relates to quantization.

"

That equation incorporates, in addition to the law of conservation of energy, Einstein’s hypothesis that light has particle-like properties as well as wave-like properties and de Broglie’s hypothesis that particles, such as electrons, have wave-like properties as well as particle-like properties.
The uncertainty principle is frequently expressed in the form
ΔE Δt ℏ / 2,
where ΔE is uncertainty in energy, Δt is uncertainty in time and ℏ is Planck’s constant.
Or, equivalently,
Δp Δx ℏ / 2,
where p is the uncertainty in momentum and x is the uncertainty in position.
We can think of time in this context as being the inverse of frequency, which is a wave-like property (note that the properties of classical particles are not dependent upon time).
And we can think  of length, in this context, as the equivelent of a wavelength, which also is a wave-like property.
Energy and momentum, on the other hand, are properties of both waves and particles.
Put energy and time together, or momentum and space together and what you get is a property of matter, called "action", denoted by Planck's constant.
In other words,  any property that can be expressed in units of action, is always measured to occur in discrete multiples of   or  ℏ / 2.
Quantization of any property is suggestive of particle-like behaviour.
So, I think it is reasonableto conclude, based on the uncertainty principle, that  any entity which has energy must have both wave-like and particle-like properties." , you are right on track. Jut my opinion, but you must be a PRO.
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Posted by archimedes on Wednesday, February 12, 2014 2:18 AM
Primordial:
A much better explanation of wave/particle duality was given by Richard Feynman in one of a series of lectures published under the title “The Feynman Lectures”. (The lectures were also published under the title “Six Easy Pieces”.)
If you do not already have a copy of the Feynman lectures you can download a copy (free) using the following link:
[See, particularly, Volume III, Ch. 1: “Quantum Behavior”. Don’t worry too much about the math.]
Well worth reading, in my opinion!
Regards,
A.
  • Member since
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Posted by Primordial on Wednesday, February 12, 2014 9:13 AM

Archimedes : Thanks for the link. I like Feynman, and Dirac, but Mr. Einstein is the best. Its sort of a hard thing to explain, I truely believe Mr. Einstein was on the right track, but just needed more time( no pun intended ). I see time as a dimension (as a requirement for the quantization of energy with information as in entropy ), but not necessary for all energy allocation. Just think about it.

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    February, 2007
Posted by archimedes on Thursday, February 13, 2014 5:23 PM
Primordial:
Thank you for your comments.
Consider the concept of kinetic energy.
We were all taught in high school that kinetic energy is energy of motion.
What does it mean to say that kinetic energy is energy of motion?
Consider an object which we suppose to be at rest.
Classically, the kinetic energy of that object would be defined by the formula: E = ½ mv2.
Since the velocity v = 0 in this case the kinetic energy of that object is zero.
But this object, presumably, has mass (m), and Einstein tells us that mass and energy are equivalent according to the formula: E = mc2.
Now, the “c” in Einstein’s formula means “the speed of light. Therefore, even though the object is supposed to be at rest, something inside that object is (presumably) moving (at the speed of light).
We do not see that something moving at the speed of light, of course, but it must be moving at the speed of light for otherwise Einstein’s formula would make no sense.
Imagine, then, that there was no such thing as time.
Then there could be no such thing as motion, and concepts like mass and energy would have no meaning.
And if you look deeply into the subject you may find that energy in all its myriad forms, whether it be energy in the form of kinetic energy of motion, or heat energy, or gravitational potential energy, or whatever, is invariably dependent upon time.
Einstein’s formula says that it must be so.
But I suppose that how one thinks about concepts like energy and time depends upon the context.
Thus, one can talk about the gravitational potential energy of car parked at the top of a hill, for example, without making explicit reference to time.
Or one could say what the current time is without making explicit reference to energy.
And so, while I understand what you are saying, as a general rule I think I would prefer to think of energy and time, not as distinct, but as complementary concepts.
But that, of course, is purely my personal view on the subject
A.
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Posted by Primordial on Friday, February 14, 2014 9:40 AM

Archimedes : I understand your position, I find myself with this same view, but if we integrate into this concept information and how it is distributed through entanglement and work from there, it appears we are leaning heavly toward a probability controlling an element of information which negotiates at something like dalta time( which takes time to a micro level ), this being much shorter than Planck and negotiates gravity, ( also dark energy etc. etc..), which are also a source of energy. So I just use my math ( delta of delta time ) and time can actually surpass Planck. At delta time entanglement is allowed, and yet partially disappears from the detection of quantized system as a sort of perturbation, but gives us such phenomenoun as black holes and dark possibilities ( as in dark matter and dark energy ) which may also include mass potential energy at some level. I try to balance all info.. I can, as in a big picture. Just think about it. Thank you for this entry it is great. Yes the E=MC^2 is this hidden kinetic we observe as potential at delta time. The KE=1/2MV^2 seperates these two sources of energy distribution and their understood reality relative to our popular view. To be potential is to not be fully understood. The same can be said of kinetic, to be kinetic is to assume obvious relative motion. I will keep.

Consider this, without an inertial reference, other than the reference system of the photon, could we set a relative direction of time ( cause and effect )(?) 

If you question the proper existance of the photon's reference system, check this out http://astronomy.com/news/2013/05/detection-of-the-cosmic-gamma-ray-horizon-measures-all-the-light-in-the-universe-since-the-big-bang . Just think about it.                       

P. S. Have you looked at D-Wave , to my understanding this may connect to these perturbations? There is an article in TIME this Feb. Issue titled "The Infinity Machine". One of our best brains, was linked to this article. Chech it out. Thank you for the exchange.

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Posted by archimedes on Saturday, February 15, 2014 7:27 PM
Very good Primordial!
Your idea of integrating information with entanglement, I believe, has a lot of merit.
As regards D-Wave, it’s a huge leap that they’ve achieved 512 Qubits. I reckon this is just the beginning.
The potential for the future, I think, is enormous.
Regards,
A.
  • Member since
    May, 2007
Posted by Bullfox on Sunday, February 16, 2014 7:08 PM

Gentlemen,

I read up a bit on entanglement in Wikipedia.  It seems you have to think of entangled particles as a system and nature maintains the uncertainty of the system as a whole even if locality and causality are not maintained.  Perhaps it has to do with keeping the amount of information unchanged.

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Posted by Primordial on Monday, February 17, 2014 9:00 AM

Bullfox : Yes, it is conservation, or if you wish, it is an energy state with a relativistic specific spatial and energy orientation element. Spin can be thought of as spin up or spin down but this is a relative position between the two entangled components. The spin rate is another momentum component, which is also shared in this same manner. Just how this works is still being studied. Some view this as a natural pairing, e.g. a pair of shoes or a photon; matter and anti-matter. The spin of the photon is whole ball of twine in itself, it presents polarization and this feature is used in chemistry to determine isomeric rotatories. And in theory, communication at speeds in excess of the speed of light, throught a similar effect presented by a niobate crystal which splits the photon into two daughter photons of lesser energy, which are entangled and control coupled delayed and reference transmitted over fiberoptics. Just my opinion.

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Posted by Bullfox on Monday, February 17, 2014 4:55 PM

Maybe in certain particle interactions there is only so much information available to mediate the interaction so the particles become entangled as a way to share the available information

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    August, 2007
Posted by Primordial on Monday, February 17, 2014 8:33 PM

Mr. Bullfox : That's a possibility, you do know they give names to properties within the interactions of the quarks e.g. flavor, is this a specific detailed bit if information(?) may be charge is coded with information(?) that's why the muon has an unexpected magnetic moment. Just my opinion.

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