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Physicist Claims Time Has a Geometry
sciencenews writes to tell us that a physicist at Stanford has just recently published a peer review website for several physics lectures focusing on a single underlying idea that "time is not a single dimension of spacetime but rather a local geometric distinction in spacetime." The science is presented quite clearly and originally uses GPS systems as a point of focus. From the article: "Not too long ago, people thought the Earth was flat, which meant they thought that gravity pointed in the same direction everywhere. Today, we think of that as a silly idea, but at the same time, most people today (including most scientists) still think of spacetime as if it were a big box with 3 space dimensions and 1 time dimension. So, like gravity for a flat Earth, the single time dimension for the 'big box universe' points in one direction, from the Big-Bang into the future. A lot of lip service is given to the idea of "curved spacetime", but the simplistic 3+1 'box' remains the dominant concept of what cosmic spacetime is like."
I suggest you read Slashdot
I agree that there aren't a lot of people who intuitively reach to the Lorentz transform to explain the progression of time, but there are plenty of obvious reasons for that. Not sure it takes a Stanford physics prof. to make what is essentially a epistemological point though.
For kicks, check out one way to visualize the spacetime wheel.
http://tinyurl.com/4ny52
If time has many dimensions then I wonder why we perceive it to go forward only (though at different relative rates depending on relative speed). The reason why we perceived gravity to point down only was just a matter of not being able to see the big picture, although I would have thought more people would have noticed the Earth is round sooner, the curve is clearly visible from most mountaintops. So what's the big picture we need to see in order to see more dimensions to time? How do we step back and notice the slight curve in the horizon?
It sure seems like time goes forward only, from my own day to day observations. My mind can't even comprehend what going another direction (except for "backwards") would even mean as a concept.
Unless you're editing a movie, it really doesn't make sense considering time as a an axis. It's almost as if time is a cohesion of forces expressed cumulatively across all forces in the universe. As objects move, the relative difference in forces expresses a change. That is time.
So perhaps time would be best understood not as a straight line, but as water sloshing around in a bathtub.
Another aspect of space-time may be a non-uniform fabric. We understand gravity as a curvature of space time. Perhaps there are multiple space times expressed via the three of the fundamental forces. Different fundamental particles are either affected or immune via these overlapping space-times. Particles affect one another via strong nuclear forces. These particles in turn affects the behavior of the whole as expressed across the three space times: gravity, electro-magnetism and weak nuclear.
Those were my thoughts.
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Spacetime perceives time as a one dimensional vector that is orthogonal to all other vectors. Because relativistic equations for time, distance, mass, etc, use a sqare root function, you get imaginary distances and imaginary time when an object exceeds C. Usually, an imaginary quantity means that you're looking at the wrong axis.
(Trivial case in point: when solving a quadratic equation, if the parabola doesn't intersect the X axis, you will get a complex number. If you break that down into real and imaginary components, the imaginary components correspond to the displacement in the Y axis for that solution's real component value in the X axis.)
Ergo, if a tachyon exists, it would experience a spacial axis as "time" and the time axis as space, UNLESS "time" is not a single axis, in which case all bets are off.
In consequence of not having a telephone-number IQ, I can only speculate wildly, but I'm going to guess that the relativistic equations do indeed refer to some measure of bleeding between space and time and that no further dimensions are required - for GPS or for any other phenomena governed by relativity. (Superstrings being about the only exception I can think of.)
I personally think that part of the problem is that time IS regarded as "special", whereas perhaps it would be better if it were regarded as special "only as far as absolutely necessary". To the extent that specialness is an extra parameter, you want to eliminate all extra parameters as far as possible (and no further).
It's a small world and it smells funny; I'd buy another if it wasn't for the money; Take back what I paid (SoM)
Some of the poo poo comments I read must echo what was said about Einstein a nearly a century ago, and about string theory a generation ago. (Though one has to wonder if M-theory works if the appearance of a single time dimension is a local phenomena. It might since the extra dimensions the math describes are less than nanoscopic and themselves a local phenomena.
Of course maybe this fits better. Maybe 3-D space is the only space that is universal or maybe like the m-theory tiny dimentions even 4-D space is twisted and warped.
That would make wormholes not these odd tubes between locations as we think of them, but just places were the warped and twisted dimensions of the Universe intersect each other.
Anyway... I looked at the main presentation and while I will never get the math, the model and how it applies to some known results makes sends. Fun Fun Fun... Did we really think Einstien would be the last to redefine the universe on this scale?
...but it must have been difficult when one went on to extrapolate from that observation indicating curvature. The problem being, if you came to the conclusion that the earth was a sphere (or at least curved), then clearly people beyond the horizon would slid right off the earth, along with trees and hills, and even the ocean would drain away. Since you knew, even in ancient times, that doesn't happen, then clearly the earth wasn't curved. The curvature had to be just an illusion of some sort. (This is only my personal speculation of how one may have reasoned.)
Really? I don't remember his measurements in his writings, but two generations before him Thales had measured the diameter of the earth within a few percent of our modern measurements. In fact, when Columbus was convincing the Spanish to fund his voyage, he had to lie to convince them that the earth was smaller than it actually was.
I don't think any culture that had a concept of "gravity" (even though Aristotle thought it was an inherent downward tendency of heavy objects, rather than a mutual attraction) that didn't also understand that the earth is roughly spherical. Hell, if you have sailboats it's almost impossible not to notice it.
All's true that is mistrusted
Not *no-one*. Hell, the Flat Earth Society was an active group until a decade or two ago. (It never caught on as well as Young Earth Creationism did, though).
Assuming the Lorentz transformation is correct without modification, then it's pretty obvious there are at least three time axes. Let's say you are travelling along the X axis at nearly the speed of light. Then there will be time contraction on that axis but not on the other two axes which have velocity = 0. But what I don't understand is what happens to time on the other axes and therefore no time dilation. In that case, how can you have time dilation on only one axis but not the others and not run into problems? It seems weirdly unsymmetric and seems to me to lead to stresses in spacetime. How can a radioactive atom moving along one axis decay tend to slower along that axis than along the others, for example?
His universe had 6 totally straight dimensions with no curvature (at least to the extent it was important to the story. This article talks about curvature in the time dimension, which was pretty fundamental to relativity 100 years ago, so this is not a new idea.
I don't think RAH's idea of rotating to make use of unused dimensions would work because most of the theories currently around which use extra dimensions assume that we can see the extra dimensions, but don't use them because the universe is closed and very short in that direction.
Also I think the waffle factor got to be a bit too much in that book. Friday was his last great book, IMHO.
http://michaelsmith.id.au
Now, as to his claims, there are many. Most, if not all, seem to me to rely on his concept of "gravitational transverse redshift" GTR, which in turn (he claims) follows from "a simple thought experiment" on slide 6 of his first lecture, "A Correction to the Gravitational Model". A little though shows his conclusions on slides 6 and 7 to be incorrect. If A sees B's clock running slowly and B sees A's clock running slowly this leads inevitably to a contradiction - an inescapable paradox.
Say both A and B set their clocks simultaneously to zero, according to an observer at rest at a point O, halfway between A and B, while the spacecraft is at rest. The observer at O also sets their clock to zero at the same time. At this point both Mayer and Einstein would say that all three clocks are observed by A, B and O to be running at the same rate.
Let the spacecraft accelerate at rate g for t seconds according to the clock at O, which continues to be halfway between A and B. Then let the spacecraft coast - becoming an inertial frame again. Now all three clocks are again observed to be running at the same rate. According to Mayer though, O sees the clocks at both A and B to be lagging the clock at O, A sees the clocks at O and B to be lagging the clock at A, B sees the clocks at O and A to be lagging the clock at A.
We now move the observers and clocks at A and B to the location of O, taking great care to do so completely symmetrically, so that there is no reason to distinguish between A and B. Here is the paradox - according to Mayer, A continues to see B's clock lagging A, and B continues to see A's clock lagging B.
This is not the same as the twins paradox. According to O, who has been sitting in the middle all this time, the movement of A and B has been completely symmetrical and there is no reason to favour one over the other.
Since the rest of Mayer's argument, especially GTR, seems to me to depend on this thought experiment, and since his conclusions from the thought experiment are wrong, his remaining theoretical arguments will fall, unless they follow from other principles.
He's going beyond special relativity by allowing both special relativity, but also the unions among geometries which, with their relativistic delays and apparencies (e.g. red shifts), explain a lot:
1) time is non-linear within the same object, when the object is accelerating (and all objects are accelerating at all times; there is no restful object in the universe--relativistically), so measurements that were thought to be predictable through redshifts are not in fact predictable through the means we've been using and
2) these new domains of time can be thought of not as time-coherency but rather non-red shift, individual object domains. Calculating domains then becomes possible, as newly defined 'red shifts among red shifts' rather than the simplistic comparison from Einstein's equations. Einstein's equations were right, but didn't consider all objects can have their own relativistic differentials in time; hence the new 'geometric' concept. I like the idea, and will mosh it through my Mathematica constructs to see what happens.
---- Teach Peace. It's Cheaper Than War.
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Not strictly true. The "bede.org" page is right that flat earth cosmology was never, ever accepted by any Christian intellectuals. But pre-scientific belief in the ancient world (for example, in Greece before the 6th or 7th century bc) the idea that the earth was flat was very common, because the things that make the sphericity of the earth apparent weren't yet obvious to them (beginning with the shadow the earth casts on the moon during a lunar eclipse). This was a time when "astronomers" had a hard time understanding that "the morning star" (Phosphoros) and "the evening star" (Hesperos) were actually the same astronomical body.
It's my perspective that Heinlein was expressing some complex ideas about the nature of reality and time in a (more or less) approachable manner. It's well known that he was friends with the likes of Robert Anton Wilson at the time (the late 70s). Incidentally, the book was first published in 1979, not 1986, as stated. In Number of the Beast, he expresses the idea that there are three dimensions of time, a concept not unknown among the leading edge of magickal theorists as a method of explaining the ability to change the future.
According to the Chaos Magician Peter Carroll, the way magic works is thus: at any given point, there are infinite 'alternate dimensions', with the 'present' being the one that we generally experience, necessarily created by the three dimensions of time, resulting an infinite number of alternate universes existing concurrently with this one, but that we can never interact with. However, there is a cone of possibility extending into both the past and the future, of different possible pasts and futures that could conceivably have created this present or conceivably result from this present. The trick to getting magick to work is in judging accurately the cone of possible realities and working towards the potential future that you're after. Most people in this society call that working towards an end. Of course, most people don't know just how wide a range of possible futures there are, and disbelieve in the power of mental effort to effect change by itself, and thus have little to no perception or experience of reality bending to their will.
Heinlein's book expresses the idea of what you might find yourself interacting with if you were able to transfer into those other concurrent realities. His concept of world-as-myth is mostly just a pleasant flight of whimsy for a professional author, based largely on the general concept of magick-- that belief creates reality. Yet also he's expressing the concept that the author is both tapping into a world already in existence AND creating that world simultaneously.
Undoubtedly this sort apparently paradoxical thinking will be found to some degree confusing and wrong-headed, yet sufficient meditation on the subject will invariably reveal its pure logic. Though I don't feel that either Heinlein or Wilson (or Carroll) really effectively described what's going on, it's easy enough to grasp ahold of the same intuitive Truth that they all wrapped their books around.
Is this new idea actually new? Decidedly not. The question is whether it'll garner any greater degree of support in this round, imo.