The Existence of God Proven!!!

[TheRobin]

First of all thank you for taking the time for this detailed explanation of the evolution of physical ideas in general. I found it a very intersting read, though I already knew or heard of a lot of them to some extend (though not in so much detail). But I still don't see how that answers my question as to how time and space are actually defined. I think the only paragraph that touches upon it was this one.  

 

 

Now space and time are completely different set of properties.  Space and time are position and time of interactions in a system.  It is more of a description of what happens than what is in a system.  However, time and space indeed have properties as well. 

Here you equate space with position of interaction in a system and time with time of interaction in a system. It seems to me these are merely synonyms (or the same word in case of "time" ) and not really definitions or explanations or the concept itself.

I mean if we were to plug that in to a later sentence of yours then it would read "We're all travelling along the position-time interaction in a  system at a  constant rate." which seems very confusing.

Also the notion of "travelling" along a time-axis seems a  bit weird on first glance. How do you define travel then if that works logically?
I mean, travel in the common sense of the word is a movement (space unit/per time unit) from A to B . But if you say traveling along time, then that would mean time-unit/time-unit, but that doesn't seem to make sense, as that would just cancel itself out again. So what am I missing here?

Would you mind explaing or extending a bit on these very basic concepts? I think  unless there's a clear understaning of the basics there isn't much point in going into the way more advanced physics of relativity.

[Robofox42]

I mean if we were to plug that in to a later sentence of yours then it would read "We're all traveling along the position-time interaction in a  system at a  constant rate." which seems very confusing.

I guess it is from all my physics classes, but that sentence replacement does make complete sense to me. 

 

I do need to explain that better though.  So to start with, we say that objects have position as a property.  If you define a Cartesian coordinate system, you can say that a particle has position (x,y,z).  For example, it is at (1,2,3) meaning the position is at 1 in x-direction, 2 away from origin in y direction, and 3 away from origin in z-direction.  This is a property of an object.  Now unlike some other properties, position is a shared property between all objects.  What do I mean by that.  Let's take the property of temperature.  If an object is at temperature 100 degrees Celsius, then we know that about that single object.  There could be a million other objects at that same temperature.  

 

With position however, there is only one particle at that position.  Define a set of coordinates, and all objects in the universe are defined in that coordinate system.  So you can see that position is a shared property in that all objects interact through the relationships they have in that shared coordinate space.  This universal sharing of coordinates means that space makes sense on its own.  Temperature doesn't make sense without an object having that property.  A position in space still makes sense even if no object has that property.  I am not saying space is an ether.  I am saying that space as a concept doesn't need an object at all points in order for a point in space to have a meaning.

 

If another particle has close enough of the same position as the original particle, they overlap and will interact.  All particles share the same position space  and all relate through that same position space.  According to modern physics, all objects interact strictly through overlap.  Fields have been discovered to be interactions through messenger particles or photons.  What this means is that the only way to interact in physics is to overlap in position and time.  So space-time is the system that all things interact through.

 

All matter objects are moving through time.  Now what does this mean.  Well, all I can say is that the way we experience reality is a constant rate of the passage of time in units of seconds, hours, days, years, etc.  Well in physics, all this really means that is objects are 4 dimensional.  An object has a position at a given time or (x,y,z,t).  Physics equations are designed to be able to figure out the probability of a system being in a state at time_future given enough knowledge of all the properties of a system in time_present. 

 

When I am talking about traveling through time, I was not being precise.  Traveling through time is not a velocity.  I was talking more about the passage of time.  We don't really think about it because it is constant.  However, objects that are traveling really fast compared to us experience time slower.  If you saw the clock of a spaceship going near the speed of light, its clock would be moving really slowly.

 

Now when you think about it, we experience the dimensions of space differently than time.  We experience positional space in fulness, but time only at one point at a time.  If we experienced x the way we experience time, then we would experience x as a scan of snapshots, not as seeing all of the objects in the x dimension at once.  If we experienced time the way we experience space, we would see a person as a snake because we would see their position over the course of their entire life which is a lot of motion.

 

Tangent.  Before quantum mechanics, it was believed that with enough knowledge we could eventually define a function for every particle such that we know the function (x,y,z,t).  In other words the function says the position of the particle for all time, or we are able to predict the complete future of the particle.  Quantum mechanics killed determinism in physics so we now know that isn't possible for future time.  In fact, we aren't even able to know a single x,y,z,t.  That is the Heisenberg uncertainty principle and it would be too complicated to go over right now.  Just understand that it is impossible to know the precise location of anything.

 

I hope this helps.

I think your explanation was pretty good Robofox. It is also a good way to understanding time dilation. You are always traveling at the speed of light through space-time, so if you are travelling at 95% the speed of light through space: you will be traveling through time to a small extent. If you had a laser with you and shone it in the direction you were traveling, you would measure the laser to be traveling at the speed of light because time is passing much slower. If you were to measure the speed of a laser some someone who was traveling at 2% the speed of light, you would also measure the speed to be the same, and this is because light travels exclusively through space and not through time.

 

That is a good way to put it.  One thing I would like to add is that when you think about it, we never travel 95% of the speed of light.  What I mean is that we are always stationary in our frame of reference.  This being stationary makes us travel completely through time.  That is why we experience time at a constant rate.  That is also why the speed of light is constant.  There is no way for us to be an observer that is not in a stationary reference frame. The movement of parts of our body compared to our brain and nervous system never move fast enough to be that much different from stationary compared to the speed of light.  So our reference frame is always still and light is moving at light speed.

 

This is what is meant by relativity.  It is valid way to think of us moving as we are still and all everything else is moving toward us, rather than us moving toward other objects.  There is no global reference frame like there is in Galilean physics.  Another object that we observe moving 95% of the speed of light has slower time.  But an observer moving along with it would see us as moving 95% of the speed of light, and we are running slow and they are normal and stopped.

 

Interesting question I like to ask people.  If you were able to stop time and still could move, how fast would you be going.  Most people would say infinitely fast.  The correct answer is the speed of light.  We don't intuitively see that traveling through space inherently travels through time.  Going infinitely fast is the speed of light.  You could travel from point A to point B in no time to you.  However the rest of the universe would experience the amount of time it took light to get there.

 

I like to imagine a thought experience that intrigues me.  What if there were some organism that was galactic sized and had its brain and nervous system stretched out and parts of its nervous system were moving at different speeds comparable to the speed of light.  I believe such a creature would not have its brain all in one non-accelerating reference frame.  Such a creature would not experience time at a constant rate.  It would also not observe the speed of light as constant.  Just a hypothetical that I find fascinating to think about.  This isn't a violation of relativity because the speed of light is always constant in a non-accelerating reference frame.

[TheRobin]

I think I understand the space concept a bit better now, but time still makes no sense, as you explained time to mean a "passage of time", which isn't really helping me at all to be honest.But to come back to my original assumption that space and time are concepts of relations of things, here's a thoguht experiment and maybe you see what I mean and can explain me the concepts relative to that.

Assume we had one blob of matter, no atoms or smaller parts that it's made of, just one blob. Now, I'd argue we could have and apply the concept of space here, meaning we could apply a coordinate set to the blob, like a map, but we couldn't apply the concept of time, as long as there's no other blob there.Because as long as there's only one blob, movement can't be measured, as movement is measured by a change in coordinates relative to another thing, whose coordinates we also know. But if there's only one thing, then that's impossible, and we also can't make a coordinatesystem "stick" onto a vacuum. So time only starts to make sense as a concept if there's another blob and I'd even argue that time at that point would still only be measurable if at least one blob has a spin along it's axis. That way you can use that as a time unit and compare the movement towards or away from the other blob against the spin.What I basically mean is, unless we have something that has a constant movement and that we can use as a clock, the concept of time is not measurable and as such not applicable to reality. Does that make some sense?

[Robofox42]

That does make sense.  I like to think of spacetime as the mechanism through which all interacting takes place.  The idea you demonstrated applies more than you think.  If there was only one blob, then no measurement of anything could exist.  That argument for time also could apply to space as well.  That could also apply to temperature, charge, etc.  Basically you can't measure anything without the concept of variance.  You can't know that temperature exists without hot and cold. If there was only one value of a property, there is no way to even know of the existence of that property.  Having only one blob, you couldn't measure space either. 

 

Internal spin can only makes sense if objects have a non-zero size.  However, time can be measured with two blobs without spin by using the time it takes for one to pass across the other with one having size.  Or without size, you could use three blobs, and time is measured by one passing both of them.  There might be other ways to measure time without spin that are more fundamental, but I just wanted to illustrate that time doesn't require a cycle or spin to be measurable.  We are used to time being reliably constant, but reality doesn't require that.

 

According to relativity, the moment you are able to measure space, you are also able to measure time.  They are interconnected and the way our universe works, you can't have one without the other.  Moving through space is also moving through time.  Cartesian coordinates with time independent of space is a mathematical model that is only an approximation to reality.  There are different mathematical models of geometry, but they don't all apply to reality. 

 

Now I think what you are asking is does something exist when there is no way to measure it.  Measurement requires variance.  With one blob (and no possible variance), basically nothing is measurable.  Does the universe still exist?  I think that is more of a abstract philosophical question and I don't think I can give a satisfactory answer.

[TheRobin]

I don't quite follow on two points.The first is that, I don't see how you could not measure space (even of only of the blob itself). Say we had a cube, we cude use the length of one side as a unit and measure the volume, surface area, diagonals and such. Wouldn't that be a valid measure of space?I also don't quite follow your time example, because if we only have the movement of one blob towards another then you have the problem that you named yourself, that you have no variance. So what do you measure then and what do you use as a unit? In the example of a spinning and moving blob, you'd have either the spin or the movement towards the other blob as a unit by which you measure the other, but if there's only one movement, you have only have a unit buth nothing to measure basically?It works again with three blobs though. Though I don't get why the zero-dimensionality is important in those examples.

[Robofox42]

My understanding was that the blob was a single point.  Having a blob that is finite size is no longer single point and can be thought of as a collections of particles or infinite distribution of matter.    Once you have that, you have as many points as you want for both the measurement of space and time.  Now in classical physics, the only way to have time variance was to have a changing system.  If the blob was always the same and parts of it never moved in relation to each other, then time is not measurable.  However, this is modeling the system as time and space independent.  In reality, you can't measure space perfectly without information about time. 

 

In relativity, you need 4 coordinates for measurements to makes sense.   This is because with only 3 coordinates, if you use a moving reference frame, then the spatial dimensions are altered.  Every non-accelerating reference frame is equally valid so the length of the blob has infinitely many values that are all equally valid.   So the length of the blob is meaningless without time because it is completely dependent on the reference frame you are using.  This is because movement through space is equivalent of movement through time.  The only measurement of length that is valid in all reference frames uses 4 coordinates (dx^2 + dy^2 + dz^2 - dt^2).  This is the distance between two events (such as traditional length by measuring the length of the blob with two events happening simultaneously at both ends).  This measurement of two events in space-time is always the same.  In other reference frames, the distance of the blob is different, but the events are no longer simultaneous.

 

What you are saying about space and time does make a lot of sense and is correct in classical physics, but it breaks down in relativity.