Is Time a Dimension? Exploring the Differences

[Hootenanny]

so my theory is : E=m

I agree with you, provided that the mass is measured in MeV/c², or if we're in natural units

 

[meteor9]

LOL Hootenanny ! Lot of hahaha , i don't have emoticons here to express my feelings.

DaleSpam , it's ok , then take it for whatever you want .

 

[john 8]

john 8 keeps asking if time is a "physical thing". He has defined "physical thing" to be either a wave or a particle. So he is asking if time is a wave or a particle.

So I invite everyone taking part in this thread to state explicitly, "no, time is not a wave or a particle" and then maybe john b will stop going on about this and we can discuss something more interesting instead.

Thank you. Thank you. Thank you.

Now we are getting somewhere.

I agree that time is neither a wave or a particle. Now this sets up the next question. As far as I know, everything that can be sensed, measured, or experienced is made of either a particle or a wave. Now I could be incorrect and I invite anyone to correct me.

You see this is how I came to the conclusion that time is not a physical thing, and so is not part of the physical universe, and so time is relegated to the understanding that it is just a concept. Do you see where I am coming from now?

This is why I came to this form, so I could discuss this understanding of mine and get it corrected if I am wrong.

If anybody can show me an example of something that is neither a particle or a wave yet exists, I would like to know what it is and what characteristics it has that gives it a specific identity, and how is this non particle, non wave thing is identified?

Again, thank you for getting the ball rolling on this.

 

[atyy]

How does one know this fundamental process is really periodic - no clock to measure it is available! The only way out is to define that process as being periodic. But which kind of process should one use for that?
Stephani, http://books.google.com/books?id=WAW-4nd-OeIC&printsec=frontcover#PPA6,M1

Maybe also try Barbour's "The Nature of Time"
http://www.fqxi.org/community/forum/topic/360

 

[john 8]

Time is not a wave or a particle.

Thank for your response.

Now we can move on to the next step. If you think that time is neither a wave or a particle, do you think that time is a something that is an integral part of this universe that can be effected by and have effects on those things that are part of this universe, such as those things that are made of particles or waves?

If so, what is this time thing?

You see I am of the understanding that in order for anything to be classified as a thing it has to have certain characteristics that identify it as this certain thing. As far as I understand all things that are considered to be a part of this physical universe and are of use or can be used in physics are made of either particles or waves.

If you say that time is measured by a clock so that makes time a real thing, than be more specific. What is being measured exactly and how.

You see voltage is a measurement of the action of electrons, this specific measurement of electrons is given the label of a measurement of voltage. So that measurement involves waves or particles depending on what school of thought you prescribe to.

A measurement of mass or weight involves atoms, electrons and such. So we are measuring the interaction of gravity on particles.

A measurement of light intensity involves waves.

A measurement of a car's speed involves an object made of atoms. Take away the atoms and there is no measurement.

A measurement of sound involves air particles.

I could go on but I think you get the point.

In fact if you think about it, measuring devices are made of particles, and in order for any measurement to take place, what is being measured has to have the ability to interact and influence those particles.

So if you say a clock measures time than what exactly is the force, energy, substance, whatever you want to call it, that is being measured and causing a change in the measuring device. If you think a clock is a measuring device, then that means that it is detecting a thing in some manner.

What would be this thing?

It would be better to just stick to giving an example of something that is neither a particle or a wave and yet is identifiable as a thing that exists in this universe. that is if you still think time exists as a thing that can influence other things in this universe, yet is not a particle or wave.

Just to be perfectly clear, I have told you what I thought time was not.

Since time is not a particle or wave, I consider time to be just a man made concept, and the idea of time only exists as a consideration nothing more.

Please correct me if I am wrong and set me straight.

 

[john 8]

The argument with john 8 appears to be purely semantic. I agree with him tha time is neither a wave nor a particle.

The discussion with meteor9 looks more interesting.

Thank you for your reply.

Do you think that time is a thing that is measured by clocks?

Do you think time is something that can physically dilate?

Do you think that time is a thing that exists as a specific thing that has special characteristics that identify it as time?

Do you think that time can have an influence on other physical things and yet not be a particle or a wave?

 

[john 8]

Energy is force times distance, force is mass times acceleration, and acceleration is change in velocity over time. So energy is mass times change in velocity over time times distance. So space and time are a fundamental part of the very definition of energy. You will have to do more than just shrug and say that they have nothing to do with each other.

Holy crap man!

Where do I start with this complete misunderstanding, misinterpretation, misleading mess?

Your line of “logic” is amazing. Is this really how your mind works?

I am sorry to be so critical but you have been disagreeing with me on my assertion about time as though you were knowledgeable in the basics of physics.

Please. Please. Please. Review your physics and clear up any misunderstood words that you have.


I am going to do you and whoever else reads this a favor and straighten out your mess.

First, your definition of energy is wrong.

If we were to apply your definition of energy to the real world it would not jive.

You say energy is force times distance. So watch what happens in the real world according to your definition.

I place my hand on a wall and push against it, I am using a force against the wall. The wall does not move so distance is zero. Force times zero distance equals zero. According to your definition there is no energy being used.

A car pushing against a bulldozer at full throttle, the car and the bulldozer do not move, no distance, so no energy? I do not think so.

Here is a good definition of energy per “The Essential Dictionary of Science”

Energy; Capacity for doing work. This work may be as simple as reading a book, using a computer, or driving a car.
Without energy no activity is possible. Energy can exist in many different forms. For example, potential energy is energy deriving from position; thus a stretched spring has elastic potential energy, and an object raised to a height above the Earth’s surface, or water in an elevated reservoir, has gravitational potential energy. Moving bodies possesses kinetic energy. Energy can be converted from one form to another, but the total quantity in a system stays the same (in accordance with the conservation of energy principle). Energy cannot be created or destroyed. For example, as an apple falls it loses gravitational potential energy but gains kinetic energy.


There are many other sources to get the correct definition of energy.

So space and time are a fundamental part of the very definition of energy. .

DaleSpam, I can site many definitions of energy that do not have space and time as a fundamental part of energy. You have made up your own definition of energy.


Your definition of force needs work.


I suggest that those who want to know the correct definition of force look to a reliable dictionary.

So DaleSpam, now that I cleared that up would you like to respond to meteor9 again?

Energy has nothing to do with time neither with space. Why should the definition of energy refer to time,.

If there are any people on this form that think time is a thing that can influence a clock or anything, take note of the underlined part of the definition of energy that I provided. If time is not a particle or wave yet you believe that it is a thing that has influence on this physical universe, you will have to explain how time is not a form of energy.

Thank you DaleSpam for bringing up the topic of energy. You helped me out in explaining my point regarding time not being a thing at all, but is just a consideration.

 

[JesseM]

John, did you think about the analogy between time as measured by clocks and "distance along a path" in a 2D plane as measured by odometers, from post 86 and post 83, and post 64 of this thread? If so could you answer the equivalent questions for odometers/distances along paths? I'll give my own answers below...

Do you think that time is a thing that is measured by clocks?

Do you think that "distance along a path" is a thing that is measured by odometers? I'd be inclined to say "yes" to both questions, although I'm not sure if you may have some specific associations with the words "a thing" that I don't.

Do you think time is something that can physically dilate?

Do you think that distance on a path is something that can physically contract? I would say "no" to both. What can happen is that difference in the t-coordinate between two events in a particular inertial frame can dilate relative to the clock time between these events (if both events happen on the worldline of the clock), and similarly if a car is driving along a path that is slanted relative to the x-axis of a coordinate system on a 2D plan, the difference in the x-coordinate between two points on the car's path can contract relative to the distance between these points as measured by the car's odometer (for example, if you're driving on a straight path that's parallel to the x-axis, then when the odometer increases by 10 miles, the car's x-coordinate will also have increased by 10 miles; but if you're driving on a straight path that's at a 60 degree angle from the x-axis, then when the odometer increases by 10 miles, the car's x-coordinate will only have increased by 5 miles). Since both of these are just contractions/dilations relative to a particular coordinate system, I would say that they should not be called "physical".

Do you think that time is a thing that exists as a specific thing that has special characteristics that identify it as time?

Do you think that distance along a path is a thing that exists as a specific thing that has special characteristics that identify it as distance? For my own answer, again I am not really sure what you mean by "thing" or "exists" here, so without definitions I'm not sure. But I'll say what I said in post 86 of the other thread, The time along a path through spacetime is at least "physical" if you just mean "there's a well-defined physical procedure for determining the amount of 'time' on a path through spacetime, and this procedure gives a frame-invariant answer" (and of course you can say the same about distance along a path).

Do you think that time can have an influence on other physical things and yet not be a particle or a wave?

Do you think that distance can have an influence on other physical things and yet not be a particle or wave? Again I am not sure because it's not clear what you mean by "influence". I think it makes sense to say that odometers "measure distance" but I don't know if that's equivalent to saying "distance has an influence on odometers", and I'd say the same about clocks and time.

 

[Dale]

First, your definition of energy is wrong.

It was not wrong, but it was slightly sloppy. Energy is the capacity to do work, and work is force times distance. All the rest follows.

If we were to apply your definition of energy to the real world it would not jive.

You say energy is force times distance. So watch what happens in the real world according to your definition.

I place my hand on a wall and push against it, I am using a force against the wall. The wall does not move so distance is zero. Force times zero distance equals zero. According to your definition there is no energy being used.

A car pushing against a bulldozer at full throttle, the car and the bulldozer do not move, no distance, so no energy? I do not think so.

These are both correct, no work is being done on the wall and no work is being done on the bulldozer. This is freshman-level Newtonian physics. These kinds of problems often stump naive students on first glance. These are both just simply cases of 0% efficiency, where all of the energy being used is used to do internal work (where there actually is force times distance on the molecular or piston level) and generate heat.

Here is a good definition of energy per “The Essential Dictionary of Science”

Energy; Capacity for doing work. This work may be as simple as reading a book, using a computer, or driving a car.

The definition of energy is correct. As I noted above I was being sloppy. The definition of work is force times distance (dot product) and all of the remainder of my earlier comments follow.

What is the force and the distance you refer to wrt the work done in reading a book?

DaleSpam, I can site many definitions of energy that do not have space and time as a fundamental part of energy. You have made up your own definition of energy.

Please do so then. Any definition of energy using the word "work" involves space and time as a fundamental part of energy as noted previously.

While you are at it, please define "wave". You are in the habit of using very non-standard definitions, so you need to be clear about what you mean. The standard definition of energy (capacity to do work, work defined as force times distance) includes both space and time as does the standard defnition of wave (the wave equation). If you are using the standard definitions please acknowledge it otherwise please post your definition.

 

[Naty1]

This is the funniest thread so far here on Physics Forums...never have I seen so many crazy conclusions and claims...it outlived it usefuless about a hundred or so posts ago...I'm out of here...

 

[A.T.]

I suggest that those who want to know the correct definition of force look to a reliable dictionary.

A dictionary? Is that where you have your physical knowledge from? How about a physics book? Even wikipedia is OK for such basic stuff, and should clear up your confusion.

 

[meteor9]

Naty , if physics and maths were not mixed with crazy 'theories' and conclusions , they would be so boring and indigestible . If the moderators here were not 'severe' in considering my posts 'misinformation' , I would go in all the other threads to make them funny and crazy , LOL !

 

[Al68]

Naty , if physics and maths were not mixed with crazy 'theories' and conclusions , they would be so boring and indigestible.

Well, I have always considered math and physics to be very fascinating. And still do. It was all the other subjects that always bored me. Of course most people thought I was crazy. Maybe they're right, but how someone could consider physics boring and literature interesting is way beyond me.

 

[meteor9]

Al68 , you are right , I think that literature is the most boring thing in the world , I prefer gazing the roof or the wall than reading literature. Math and physics and generally speaking all exact sciences are to me the most exciting fields for reflexion , pondering, researches or passing positively our 'time' . Simply I think that in an online forum which is not something formal with vital sanctions , expressing funny or 'crazy' things will not destroy or injure someone or something , anyway the moderators are here to remove all sort of non-sense statements .

 

[mangaroosh]

This is a very common claim, but it is simply wrong. Math is the language of logic; if the universe behaves logically then it can be described mathematically. It is as simple as that.

IMO, a non-mathematical treatment of physics is like reading an English translation of Tolstoy. You can get the plot and understand the story, but you miss all of the subtle things that make him great. As divorced from "reality" as our mathematical models are, our verbal descriptions and plain-language models are far worse.

the thing I believe that has to be remembered, is that while math may be the language of logic, it remains merely the manifestation of our understanding of the universe translated into that language, with all the inherent assumptions, both conscious and subconscious. If the underlying assumptions are in anyway erroneous, then the logical conclusions that follow, while they may indeed be flawlessly logical, they will ultimately be incorrect.

I would argue that plain-language models are perhaps more just as accurate, so long as the most accurate description of each word is known, or reference. There is a certain logic to language also, sometimes more than we realize, as, and this goes for myself, we often do not truly understand the words we use, rather have a vague approximation of what they mean, based on a contextual understanding.

 

[mangaroosh]

Well, I'll give it a shot. Distance isn't made of particles or waves. Is distance physical?

Time, like distance, isn't composed of particles or waves, but is used to describe intervals between physical events. This is why time is referred to as a dimension, because, like distance, two events can be separated by it. And this simple fact is the reason time (and distance) are useful concepts.

And any useful definition of time will be very similar to a useful definition of distance, in the sense that both are intervals between "physical things", not "physical things" themselves.

So, yes, time is a dimension instead of a substance.

would that suggest then that time as a dimension, or perhaps a bar measuring time, would be akin to the X, Y, and Z axes?

 

[mangaroosh]

I am not trying to construct a working theory of physics without time. You are adding some requirement to this time discussion. If time was physical then its physicality would not depend on what I thought.

You say time is physical, and have not provided any evidence of how time is physical. If time is physical then it will exist as a particle or a wave. Just explain how you think time is physical.

You need to explain why you think time is physical. The burden of proof lies with you.

My assertion that time is not physical is not speculation, it is based on the fact that there is no evidence to support the idea that time is physical, and the fact that you have not said whether time is a particle or a wave, or given any explanation of how time is physical proves my point. You still have not given any evidence that time is physical.

Lets make this simple. I have told you why I think that time is not physical, you tell me why you think time is physical.

this could quite easily be born out in later posts, but my perception of what you are trying to get at, is the question of how time can be said to make up the "fabric of reality", if it does actually make up the fabric of reality or whether that the notion that it does is purely based on an assumption that is inherent in mankind, based on a misperception of reality.

Also, whether or not this is borne out in the extrememly logical mathematics that have as a starting point, this potentially erroneous "axiom".

 

[boysherpa]

Well, I started this thread, and dropped out, and came back to see what had occurred. It is clear that there was no general agreement reached regarding my original question. This original posting was not an idle question, but rather, it was a real question into the way we investigate nature today. The volume of responses indicate that there is some disagreement and confusion regarding time in commonplace and advanced physics. Also, the general level of understanding of the use of mathematical modeling in science seems to be below standards. It is easy to quote equations and their use - but do you understand what they are modeling? I have taught this for many years

One thing did catch my attention - the understanding that the concept of time, and mass, and other physical quantities, are sometimes difficult to pin down in a specific sense. It is difficult to define mass in a manner such that it can be understood other than some intrinsic property, tied up with forces. To say that mass is defined by mathematics seems to me to be illogical, as the universe does not seem to be run be mathematics. Rather there interacting forces and particles which seem to obey laws and principles. Mathematics is an excellent language to express these laws and principles. Those who view the universe otherwise (run by mathematics) have, to me, an egocentric view of nature. They also normally do not understand mathematical modeling, which is invariably only an approximation to nature.

 

[Fredrik]

Well, I started this thread, and dropped out, and came back to see what had occurred. It is clear that there was no general agreement reached regarding my original question. This original posting was not an idle question, but rather, it was a real question into the way we investigate nature today. The volume of responses indicate that there is some disagreement and confusion regarding time in commonplace and advanced physics.

I made lots of posts in this thread, and I honestly don't remember even seeing your original question. The volume of replies here was caused by a number of bizarre claims made by a few individuals, in particular john 8, and most of the thread has been about those things.

Regarding the concept of spacetime, I can assure you that there are many people here with a solid understanding of it. This is not a controversial subject.

Also, the general level of understanding of the use of mathematical modeling in science seems to be below standards. It is easy to quote equations and their use - but do you understand what they are modeling?

Yes.

By the way, there is absolutely no way that anyone can understand an aspect of the real world (that can be studied scientifically) better than a person who understands the best theory about it. To "understand the theory" means to understand both the mathematical model and the axioms that tell us how to interpret the mathematics as predictions about results of experiments. Also, the only way to answer a question about something in the real world is to explain what some theory says the answer is. This is because science is the only way to learn anything about the real world, and science is essentially just the process of finding new theories and doing experiments to find out how accurate the theory's predictions are.

Please keep these things in mind when you read answers like my post #21.

To say that mass is defined by mathematics seems to me to be illogical, as the universe does not seem to be run be mathematics. Rather there interacting forces and particles which seem to obey laws and principles. Mathematics is an excellent language to express these laws and principles. Those who view the universe otherwise (run by mathematics) have, to me, an egocentric view of nature. They also normally do not understand mathematical modeling, which is invariably only an approximation to nature.

This suggests that there's something lacking in your understanding of the concept of a theory, in particular regarding the connection between the mathematics and the real world. You seem to think that someone who uses an exact mathematical definition is confused and doesn't understand that theories are at best approximate descriptions of reality. This isn't the case at all. Every concept that has any relevance in any successful theory of physics has an exact mathematical definition. This is necessary to ensure that everyone who uses a term like "mass" is talking about the same thing (assuming of course that they understand these things). Also note that a theory can't make predictions about results of experiments involving a concept that's been defined without mathematics). This is because a theory is defined by a set of axioms that tells us how to interpret the mathematics as predictions about possible results of experiments. In particular, if you define "mass" as something other than a mathematical term, the theory isn't making any predictions about it.

 

[boysherpa]

This suggests that there's something lacking in your understanding of the concept of a theory, in particular regarding the connection between the mathematics and the real world. You seem to think that someone who uses an exact mathematical definition is confused and doesn't understand that theories are at best approximate descriptions of reality. This isn't the case at all.

I agree with part of your post, but not this part, as it does not follow from mine. Perhaps I was not stating my position clearly. What I meant to say was that merely stating a mathematical expression is not a definition and cannot explain a physical event or effect (especially since many mathematical expressions, with a simple change of variables, describe a completely different effect). It is a part of the definition or explanation (or theory), but not the definition in toto. What I see too much of in these and other forums in the tendency to merely posit a mathematical expression as proof. The individual then says something to the effect of "math doesn't lie". The mathematical expression is simply a model, and, beyond that, a model of the theory. Furthermore, my position is that nature does not obey mathematics. I was not, and did not, claim that one who uses mathematics is confused. I sincerely doubt this statement shows any lack of understanding of the concept of a theory, as you claim, but opinions do indeed run rampant...

 

[Dale]

What I meant to say was that merely stating a mathematical expression is not a definition and cannot explain a physical event or effect ... It is a part of the definition or explanation (or theory), but not the definition in toto.

Obviously. But we are writing posts on an internet forum, not textbooks. What do you expect? That we write a 10 chapter dissertation rigorously defining each term in response to every idle question?

If someone cites a formula or uses a symbol that you don't understand then ask. But those symbols and formulas are the most compact ways to relate important physical principles. So don't complain that someone uses a one line mathematical formula rather than several paragraphs. And don't make the rather insulting assumption that the person providing the equation is somehow ignorant of anything else.

 

[ccm.student]

I question this also. Disregarding any mathematics used to prove or provide any information. Theoretically math can work it is a specified formula that we made to fit a function, so even given that it works does not necessarily mean that it is correct.

First based off of some of the new ideas by physicists (through the wormhole with morgan freeman). Michio Kaku in particular i believe promoted the idea that anti-matter is matter flowing back in time. When we do look at formulas they consist of time in most formulas concerning distance. It works, however; time is a perception or byproduct of change in an environment. It is then the byproduct of the 2nd law of thermodynamics. It is somewhat confusing. How is time both a value, sometimes a formula, and also a law, in accordance with a dimension. We don't use 1,2 or 3d in that perspective. They are simply a plane in which things exist or work. What if we have it wrong, what if we haven't found the 4th dimension, does it exist.

This is merely a question. I am not attacking physics or any great physicist. Just asking a question to something we have no exact answer for, and additionally we take with absolute faith, we get nowhere without questioning things.

 

[bobc2]

So, how can we group time with space? It would seem time is something wholly different, and perhaps not of the same substance.

Any help?

Imagine driving from point A to point B along an interstate at exactly 60 mph. Signs are posted at every mile along the highway. Instead of posting the miles traveled since leaving point A, the signs post the time in minutes. So, at every mile post along the way the time is incremented by one minute. Thus, we measure our progress along the highway as time.

Mathematically, the progression along the path is measured as time. Now, does that make the dimension along the path a time dimension? We can always calculate the distance traveled by X = vt = 60t (X = distance in miles).

Does moving along your world line along your 4th spatial dimension at speed c make it a time dimension? We can always calculate the distance traveled by X4 = ct (X4 = distance along the world line).

 

[ccm.student]

In that instance couldn't time be 1d, so time is only relative to the object we look at. It is the distortion of change we measure. So how could a plane specifically designated to time work. By now I have across many ideas of what it is and associates, however; time seems isolated from everything. Yet there is evidence surfacing that time seems to leak backward into current time. Gravity is even being considered as a separate dimension. Taking this idea I had and testing it in math seems somewhat impossible. I recently tried to imagine leaving time out and considering that there is a different 4th dimension. this would be comprised of multiverses so close together that they are woven far beyond a subatomic level where the laws of quantum mechanics might permit it. I then took the idea further thinking that these forces that we find difficult to explain, time or gravity, even anti-matter and tried to picture them as forces exerted from parallel universes that leak through even though they are not able to be seen physically. Could this even be possible?