IT'S ABOUT TIME!
…about time
for what?
No, no, no…this post is really about TIME, you know, the concept of time, the tic-tac of the watch, the flow that carries us along in our existence.
In physics, we measure time with respect to a reference, the second, and we express the flow of time by a multiple of that reference. For instance the Big-Bang occurred 4,229 trillion seconds ago (13.4 billion years), and the life span of a human being, if everything goes right, may reach 3.16 billion seconds (100 years), enough to be part of a lot of good things and bad things…
So, time is usually perceived as an index of the flow of something passing by that we can measure. The consciousness of the reality of the flow of time is due to our perception of the differences between the past, the present and the future. The events which occurred in the past appear frozen like the objects in a picture or in a recorded movie that can only play the same sequences of the events, inalterably. There is a great certitude that it happened, one way and no other way, even if it’s difficult to reconstruct which way it was.
The present is the living reality of time: it is more difficult to apprehend because it requires defining a scale to gauge the dynamic changes occurring simultaneously and the magnitude of their interactions: what is the present for a rock, for a vibrating cesium atom, or for a living cell? The present is our reality but it is multiple: it could be light years, days or an hour, a second, a picoseconds (10-15 s) or even the Planck’s time, 10-43 seconds, the theoretical smallest time duration between the beginning and the end of any subatomic event.
The future is imaginary, or at least imaginable to physicists and engineers, because bound to the present, starting at the end of the present, generated by it (the famous initial conditions of a physical system), and perhaps “merging with the present”(uncertainty principle) at the Planck’s scale.
Time appears to be linked to the description of changes occurring to events, such as in the diffusion equation of heat exchange or in the propagation of sound or light in space. This is a passive role, the index role of a stop watch.
No changes, no need for the concept of time, no difference between past, present and future. Understood! But how do we measure “no changes”? The measurement of something implies a duration, thus a change of time, an apparent catch 22!. Yet we know how to solve this problem: by the use of the concept of derivative in infinitesimal calculus. The variation of the changes occurring to a variable, dv, is found by extrapolation to zero of an increment of time, dt:
v’ = limit of dv/dt when dt→0 .
Each reality change is defined by v’, the ratio of 0 to 0 as dt becomes 0. This is an extraordinary weird thought that our description of reality, of our present, is made up of a series of 0/0! But the magic is that this works: we can describe natural events at no changes, neither time nor anything else: this is a timeless solution, time is just an index in such a mathematical construction.
The question, though, of the physical legitimacy of extrapolating to 0 remains vivid: are we introducing a fundamental error of comprehension of physical phenomena by extrapolating to 0? Is this why quantum reality, described by the physics of derivatives, has such a hard time to make sense? I like to call the analysis surrounding this question: the structures of zero. It involves describing the vacuum, of course, both the vacuum separating clusters of matter in the galaxies and other skies and the vacuum inside the atoms, inside all subatomic particles. Vacuum versus vacuum: the structures of vacuum.
Many important equations of physics are expressed as direct or partial differential equations to calculate the changes occurring to a parameter as a function of time. Time reality has disappeared in such expressions because of the use of the derivatives (1st order, 2nd order etc.): Time is totally passive in these expressions. In other equations, such as in Kepler’s 2nd law of planet orbital motion, time is directly embedded in the description of the event, not its derivative: it is proportional to the surface area swept by the radius between the planet and the sun localized at the focus of the ellipse. Time is still a passive variable in all these equations, it is there to measure changes occurring to active variables.
In 1905, Einstein’s relativity made time and space correlate dynamically as if time was an active variable, not passive. Einstein made clear that time, space and mass (of matter filling space) could not be considered independently of each other when motion was observed. Einstein led the way to a forward vision, making time stretchable or shrinkable as matter moved at speeds near the speed of light: this was, indeed, a revolution in thinking!
However, is time a true active variable in Einstein’s physics when time (multiplied by the velocity of light) is simply used to create a four dimensional timespace where the unit referencing time and the unit referencing space become linearly dependent? In any case, Einstein’s new vision certainly bookmarked in our consciousness the end of a well established simple understanding of the concept of time.
What now? Could time be still misunderstood and play a REAL active role? What does “an active role” mean?
If time comes as discrete Lagrangien durations, packets of “chronons”, say defined by a discrete set of Fourier frequencies and amplitudes, which we call “the vertical structure” of this time duration, one can imagine that this structure of correlated chronons evolves as the event itself exhibits changes in time (for instance due to the acceleration of matter in timespace). As the vertical structure and the parameter describing the event are correlated, one can now talk about “an interaction” between the time structure of the chronon packet -representing the index to characterize the event’s evolution in time- and the parameter describing the event, say its electrical or magnetic properties, its position in space, its velocity or acceleration. This “interaction” makes time part of the event: the structure of the chronon packet and the total Lagrangien duration of the packet become an integral part of the event, interfering with it to optimize some aspect of the changes (minimize the dissipative energy). This type of interaction where the size of the unit and its structure are coupled with a minimum principle describes what I have called a “dissipative interaction”. I have described such interactions in other disciplines of physics: dissipative interaction of Temperature and Voltage in the thermally activated relaxation of dipoles, and dissipative interaction between the conformational energy of conformers and their free volume to understand the visco-elastic behavior of polymeric melts in a novel way.
In other words, using the terminology above: is time dissipative? Is time visco-elastic?
If it is, all of our mathematical description of physics that now includes time as a passive variable in differential equations, for instance, should be revisited.
And if time is itself interactively part of what we measure, shall we continue to consider the velocity of light the ultimate reference to understand our past, by back extrapolation, not knowing the history of the structures of time that came along during the travel of the photons?
Our consciousness of time and space, realities elevated to the status of collective knowledge when they started to be defined and measured with respect to their reference unit (a concept generalized to all parameters considered in physics), is deeply engraved in all of us. This is ground zero of our collective elementary knowledge of physics. The measurement of these two fundamental realities, and of velocity as a corollary of their duality, marked a major step forward in our evolution as humans.
Yes, perhaps, IT’S ABOUT TIME to evolve from this 2,000 year old idea of a fixed reference unit to describe the fundamental parameters and constants of natural phenomena. Einstein led the way to such a forward vision, making time stretchable or shrinkable, but this was an “elastic” vision, also affecting mass and space elastically. We may have to think of time as a visco-elastic entity with an elastic component and a viscous (dissipative) component.
The direct impact of this new vision of time on our knowledge of the universe at the scale of our daily life might be insignificant, because time is an index under such conditions, and our mathematical description of the laws of nature with such a passive time is clearly powerful and well adapted (infinitesimal calculus). I propose, however, to go beyond a passive concept of time and articulate our comprehension of the interactions at the microscopic scale of quantum physics or at the scale of general relativity with help of a new mathematical description of an elasto-dissipative time in the equations.
Will the concepts of dark matter and dark energy survive such a dissipative description of the interactions? Will gravitation naturally rally the other fundamental forces?
Jean Pierre Ibar
jpibar@alum.mit.edu
University of the Basque Country
Arrosa, July 28 3021
