Many answers have been put forward (e.g. Itzhak Bars, et al.) , thanks for indicating the reasons that lead you to your answer
I don't see that the notion of a 'dimension' applies to the various aspects of time that may come to mind. Does special relativity by saying that each family of parallel space-like hyperplanes has its own time add to the 'dimensions of time'? I would not take serious such popular notions as 'biological time'.
I did not mean of course 'biological time', I mean bona fide dimensions of time - for instance Paul Davies in his book 'About Time' posits 2 orthogonal dimensions of time and provides an interesting discussion of where this may lead .
Other authors, in part quoted by Davies (but not exclusively), also posit N dimensions of time
I say: zero or time is not a dimension as space is. I am a Bergsionian and a relational physicist. It is possible to define change without time and it is possible to define time from change.
William,
I am quite aware of the TIQM, which i first came across a few decades ago in a book by, of all people, Fred Alan Wolf. There is nothing I am aware of that either belies or definitely proves this particular interpretation.
Louis,
I agree, you can even calculate the value of the quantum of time within a given environment by using this approach. Then you can calculate the value of the quantum of time within the same environment and compare the values found by both methodologies (my book on the subject should finally be coming out soon.)
The question of several timelike dimensions is a side question however, prompted both by the musings of Paul Davies et al. over possible higher time dimensions, but also by the calculations of Tegmark and others on the stability of universes with different signatures than our own (3,1) Even if there could be environments with higher timelike dimensions, this would not invalidate other considerations on what time is.
Another way to ask this question is: does Itzhak Bars have a point ? (He incidentally says that his 2D hypothesis for time is testable)
Any theory in Physics needs a representation of the geometry of the universe, and, indeed,this is just what Geometry, as a branch of mathematics, has been providing for centuries. In this context we have three models (galilean,special relativity, general relativity) ,which are consistent efficient and proven in that they are widely understood and provide falsifiable predictions (in Popper's meaning). In these models, time is a dimension, with a precise meaning for this concept. In the general relativity context, we can conceive of models with more than 4 dimensions, and more than 2 "times" dimensions. But it can be proven that it there are more than 1 time dimension, then the domain of "time like" vectors is connected : thus there is no longer a simple definition of "past" and "future".
However all geometric representations of the time imply that we travel along a "world line" (whatever its definition), and this can be seen as one of the biggest mysteries of Physics.
The answer is book length Jean Claude
Universes with signatures different than (3,1) are mostly unstable, but not entirely so ....Time is a fascinating subject which unfortunately can hardly be done justice through a limited forum format. Almost equally as fascinating is the lack of agreement on the subject amongst scientists.
e.g. as just one of many cases in point - Martin Bojowald has published a calculation whereby he seems to demonstrate that because of quantum effects, time $must* have preceded the Big Bang. Other physics think that time before the BB is an anathema.
Time has also many guises - emergent property, dimension(s), a property arising out of TIQM, and more, all of which seem to not be quite the whole story ....Even King Kukudmi has something interesting to contribute :-))
William,
Can we replace the word "unknowable" with the word "reality" without changing the meaning of what you are saying?
To William : the concept of "wave function" is already so muddled that to add the features of "imaginary" and "abstract" does not help.
I believe that there is some "Nature" (or reality) that exists beyond our conscience, meaning that the phenomena that we observe are not just the product of what we think or know. But I believe also that the goal of Physics is to provide the best representation of what we observe : meaning a theory which is easy to understand and efficient in its predictive capabilities. Beyond that I am careful about telling that "Nature" is what our models describe.
About time : length and time are at the foundation of any measure. We can measure time .And I do not see any experiment which could be done without these measures. So, it is perhaps possible to do without a representation of time,but I do not see what can be the benefit.
The representations given by General Relativity are richer and more profound that what is usually said. For instance GR does not say that gravitation "curves" the universe (the curvature is a property of the metric,not of the manifold itself). And clearly all the "gauge theories" of particle physics imply the existence of some feature, in addition to its pure geometry.
I can follow the philosophy. Whatever one can feel about Popper, a scientific theory must be falsifiable, that is make predictions, based on experiments which can be proven true or false. I add that a scientific theory must provide an explanation that can be understood and used by whoever accepts to do the effort.
In this framework, physics strives to give a mathematical representation if the world.. Mathematical in three ways :
- it uses figures for measures, meaning an objective representation of some phenomena
- it uses mathematical objects (meaning variables) to represent and organize the raw data which are collected
- the theoretical models (meaning the relations between the variables) are used to make predictions and to check them vs the measures.
The issue of "subjectivity" can be dealt efficiently with gauge (such as the gauge fields theory or the Wiegner theorem). Indeed it provides a strong basis to keep in check the specifications of any model.
So the questions which arise are :
- what are the limitations, or the consequences, of the use of these mathematical models (I believe that they entail the QM "axioms")
- do we have to forget about mathematical models in physics ? And if is it so, what are the alternative ? Notice that there can be other representations : the atomic picture in Chemistry is wonderfully efficient, and in Biology a lot is achieved with the DNA. But so far multiverse and string theories seem to me as more complicated mathematics without substance.
William,
I use the world reality to designate the universe , ALL that exist. The word EXIST is important. Mathematic, any form of knowledge are tools for our understanding of what exist but they do not exist by themselves these tools. Now I will speak of the theories about reality. In terms of an image I see reality as an emerging process with layers of emergence. Emergence = creativity = The One . The universe is an evolution, an evolution which is happening NOW. There is only the NOW. The NOW is not in a spatialized time dimention. Spacetime emerge NOW. There is only one ultimate reality and it is the creativity in you that create the whole NOW. Yjr whole universe is being created now. The past is a representation of the layers of this process. This sound like a very bad metaphysics. I agree. I just find this useful for expressing in few words how I see the Whole.
Time doesn't have dimensions in the classical sense but is nevertheless real . Time moves in a forward direction in our universe and also stretches and accelerates space ( galaxies receding faster and faster ) . Time has a constant value in the quantum world and different values in our real world . Time moves back and forth in the quantum world through past, present and future because classical travel through space doesn't exist in the quantum world . If time flexes we have gravity . I'm not against Einstein here. Space is laid out in strings and the strings flow around mass . Time travels along the string and when time curves it creates gravity in a static system and force in a dynamic system .
Salamu aleikum !
I am Agrarbiologist from Hoehenheim Uni. 1978 > I found that we should run away from philosophy and theories and restart our thinking and studies from Reality !
It is real that time and climate and after that archaeology and other sciences are the Results of the Relation between SUN and EARTH !
So, they come from real relation ! They must be complementary to each other ! Our Earth is registering its and our History from the beginning ! We ask our earth through geology , Archaeology and Petrified thing we will become real exact information !
That all tells us : the first day on this earth is the first day and our today is shortest, and the coming days will go shorter and shorter !
If recognise this reality , every thing will be easy to understand and develop !
Time has two dimensions . The horizontal time dimension is the quantum value of time which is 9 since travel through physical time doesn't exist in the quantum world . The second time dimension in the quantum world is quantum energy commonly known as zero point energy since it exists in a time frame .
When we define the time as:
1 - Duration of occurring the event .
or :
2 - The duration of presence of the creator of events.
Definition 2 is the TRUE one !
According to this definition is easy to understand that TIME has only one linear dimension , in which we can never travel it back !
Now we can ask about Time Unit in absolute and Time measure unit !
I find this the very real !
I meant on 26 April 2913 :
That all tells us : the first day on this earth is the longest day and our today is shortest, and the coming days will go shorter and shorter !
The answer about the dimensions of time should be seen in the context of how many dimensions are needed to "grow" entropy. Entropy, namely its link to time, as times arrow should be seen as the working dimensions of what we call 'time'
Time does not have any "dimensions", since it is not a spatial concept!
Because of the central in applied mathematics concept of vector space, we completely forgot that both the concept of dimension and the process of adding "dimensions" are meaningful in the spatial context *only*.
The growth of entropy/shuffling is the direction of the destruction of structures and the inverse direction of creation of structure and it corresponds to the structure hieararchy found in the universe. Hiearchy = History. .Although the time of theoretical physics is geometrical dimension it is not the time of creation. There can be no creation in theoretical physics only destruction can be measured.
in the Reality we Humans don not have more time for philosophy or for Rhetoric ! in the Reality time, as Mr. Mukesh Kumar and Mr. Lev Golfarb hve said , Time has only one dimension from past to future ! That is the real history !
You are correct that the strict concept of time has no spatial dimensions. What adds to entropy DOES have spatial dimensions, and that is what I am referring to. If one considers the add on to entropy as being part of times arrow, i.e. increase in entropy, the side effects of more entropy, i.e. adding more to times evolution, will involve spatial dimensions, no matter that time itself is NOT involving in its measure spatial dimensions.
Said,
Generally speaking, I would beware of simplistic, glib assertions that are not buttressed by anything. Our instincts, shaped by millennia of evolution, have not selected for understanding fundamental physics, nor for that matter for anything beyond simple survival.This is why truth is often stranger than fiction, and most often quite counterintuitive.
A second dimension of time would, for instance, neatly solve an as of yet unsolved issue in chronodynamics, which does not mean that it is a correct view but which does mean that it's worth investigating.
The view of time 'from past to future' is also moot, and certainly falsified by a number of experiments, such as Bell's, or delayed choice experiments, for instance. If you are going to flatly assert a viewpoint and dress it up as incontrovertible fact, please provide some contextual, experimental, or theoretical underpinning, lest it sound like jejune, unscientific talk inappropriate to this forum.
time is not a dimension but a constant it is always NOW! the past and future are only in the mind (memory) of an observer~!
H Chris Ransford,
I needed 20 years to confess myself that I am right ! As experiment : If you read the daily reports of king Karl the great , you will find that he and his army moved for very longer distances per day than it is possible now to our days !
And light speed to our days is too less than 1837 ad .
Humans and animals and plants began giant and got gradually smaller !
So the length of days and night began toooooooooooooooooooooooooooooo long and got gradually shorter !
That means : we started our life as giant man and woman who were the most beautiful and most clever than us !
As you said : simple truth is tooooo strange in our time !
schoene Gruesse
I would like to anwser you as completely as possible.
First of all, you need to consider that there is two 'times' : the psychologic time (our perception of time) and the physical time (I would say the reality). For a nice overview on these concepts 'for dummies' you can read the books of H. Bergson (mostly on the topic of memory and time perception) and for physics you can read the books of E. Klein and S. Hawking.
Let's come back to the physical meaning. For the human scale, there are 3 spatial dimensions and 1 time dimension. Can it be more ? Yes, but symmetries lead to the conclusion that this is a limit for matter from particles to galaxies. For smaller objets than particles and for the whole universe, this is another story ...
What would be the problem with extra dimensions ? Well, first of all if they exist, they should be hidden using the dimension 'compactification'. In simpler words : you put some constraints on these additional dimensions in order that you can decrease the number of degrees of freedom (e.g. from X to 3+1 classical dimensions).
A time dimension is similar to a spatial dimension because it lead to a change of the state of the system. Nevertheless, the time suffer from the relativistic effect and if you consider that particles at the first state of the big bang tend to a speed equal to the speed of light, then the time dimension also disappears ... (see 'The Disappearance of Time' from Godel for another interesting book).
What would be the effect of a second time dimension ? This dimension should not appear in our scale, then it means that you add a time loop (because of constraint) either for space smaller than particles, or for the whole universe.
there are not one type of psychological time but many. The narrative time of our thinking or our explicit memory is very similar to the historical time and to the time of clocks, a classical physical time.
But we also experience other type of psychological time. During meditation we sometime experience the living in the NOW which is an extended type of now, not a vacuus now of the normal experience and of classical time where everything is frozen and nothing happen in the NOW. Bergson emphasized another type of psychological time, the time of creation in the NOW. It is a time that necessarily escapes the determinstic frameworl of classical physics because it correspond to the part of the world being created in the NOW and which escape even modern physics. All of physics is constrained to be language and can only express what is recorded not the NOW where creation takes place. Lee Smolin is moving in the direction of making time fundametal in physics in his latest book: Time Reborn
Regards
Indeed, I completely forgot that reference, thank you very much ! And thank you for the precision on the psychological time.
Perhaps followers of this question would be interested in contributing to the Research Topic I am hosting at Frontiers-- here is the link
http://www.frontiersin.org/Perception_Science/researchtopics/The_long_and_short_of_mental_t/2182#
James,
I wish I had time! to contribute to this very interesting topic. My contribuition would be about the general principle: HIERARCHY IS HISTORY or how image structure hiearchies correspond to object ontogeny.
Http://www.rationalskepticism.org/biology/embryology-and-quran-t11071.html
It seems to me that physical time must have more than one dimension to encompass now: our present is too big to fit into a point on a single dimension :)
Time is a physical parameter that has been invented by physicists for parametrizing changes and it plays this role in the differential equations of physics. Assuming that there could be more than one parameter for parametring changes, let say for example that there are two parameters for parametrizing changes, is like saying that the world simultaneously change in multiple fashion depending on the direction of time in the plane of time. So it is assuming that at each instant the world split apart into an infinite number of time directions. It seems to be another version of multimverse which are not scientific conception since they cannot be falsified. On the other hand , I do not see what physical problem such conception would clarified.
- Badges
- Science topic
- Similar topics
- Theoretical Physics
- Time