should space and time be measured in the same units?

Question

I think the point would be to describe things moving at near light speed relative to us without having do any transformations.

I'm really just starting to learn this and am trying to visualize the universe in my mind.

I was just reading something similar to what JonV was describing and wanted to hear some more opinions.

That is a nice hat T.

Answer 1

In relativity, time multiplied by c, or even ic, which has units of distance. This is convenient since the Lorentz transformation between inertial reference frames is mathematically equivalent to a rotation in (x,ict) space.

Steven Hawking has suggested that ict is actually the "natural" way to look a time since the need to consider an initial condition to the universe then vanishes. The tangibility of "real" time, then, is simply an illusion associated with our limited ability to perceive the world around us. Pretty heady stuff.

Answer 2

To what point? Why would you do that?

Classical physics says we are a four dimensional universe; each dimension deserves its own units of measure. Why? Because each of the four dimensions is needed to pin point exactly where anything in the universe is and where anything in the universe is going.

Further, space units are vectors; time is not. That is, we can specify a direction for each of the three spatial dimensions; while time just increases in value...it is a scalar having only magnitude.

Clearly, spatial dimensions can use the same units; they have similar characteristics (e.g., magnitude and direction). But even these can have different units when the three dimensions are specified in spherical or cylindrical coordinates for example. In spherical coordinates, the three dimensions can be specified as r,omega,theta (or something similar) where r is a linear unit, but omega and theta are angles.

No, space and time should not be measured in the same units. To do so would be inconsistent with the physics of these quite different physical phenomena.

Answer 3

For space to be an entity it must be a special substance .With out the substance of space there would be no gravitational phenomenon.
The pressure of space is related to a quantity which we call time.
Time is measured on earth in units of seconds.
Space pressure is measured inversely proportional to the squared of time.
So space status is relative to time.
In the case of velocity its related to the expansion of space (which is defined as a displacement distance) per unit time.

We can mathematically deal we inverse velocity as well.
Or we can make calculation using the product of distance and time. It would all depend how you calculate gravity energy ,gravity power or gravity force. Equations can be formulated to accomodate any units. The preferred Units are distance per Unit time rather than then the product of meter and seconds.
The idea of space time was formulated by Minkowsky. It is an imaginary spacial geometry. Einstein used this concept to formulate the Field Equation which dealt with an abstract geometry of space called manifold. The left component of the field equation refers to the Units of space curvature.
Since spacetime involves a manifold it may or may not represent the real world, only imaginary numbers.. Hence to give real units to space time would not be relative to the real world that we experience as time and motion.

Answer 4

It's possible to use so-called natural units, in which the speed of light (c) is defined as 1. That way, c drops out of all your formulas, and space and time are treated on the same footing. Very clear and convenient.

Answer 5

Space is defined by time, and it requires mass to form the concept of time. The physics trilogy describes what you wish to know. The trilogy is: E = mc2, m = E/c2, and c2 = E/m. The last is that for a field of gravity or that of physical time, and it it exists because of a mass to energy relationship. Notice in the first two equations that the basis of each is that of the c2 concept. In the first energy is found by the multiplication of this value while in the second it is the divider. This value is the basis of our physical existence and determines what reality is. Our reality exists only for the duration of the time forming it, and this moves from the present into becoming that of the past at the speed of light, because that is what we, as our universe is completely composed of. So there is but one value in existence, that of time.

There is a short writing at http://360.yahoo.com/noddarc entitled "Concepts Concerning Time, Gravity and Energy" that may be of interest.

Answer 6

It's not referred to as space. IT's called spacetime b/c that's all time is. So yes they have the same units. But this concept is much more in depth than what you're making it.

Answer 7

They are over great distances and technically given the definition of a meter in wavelengths it is the same for short distances, we just do not always think of it that way.

Answer 8

I think i know what youre saying. if its space like outer, no because space cant be measured in minutes. if its space like here to there, same.

Answer 9

no.By the way L. what do you think about my new hat ?