#### It is easy to recognize someone who isn’t a physicist. They will use the word *dimension* when referring to a *number line*. More amusing still, they will begin to bend and warp the alleged ‘dimension’ in a vain attempt to provide a physical interpretation to the workings of the Solar System. And that in a nutshell is the fundamental problem with the word *time* . The non-physicist has yet to realize that time is not a dimension, but rather a number line.

**The word ***dimension* belongs exclusively to Physics

*dimension*belongs exclusively to Physics

#### Let’s spell it out. The word *dimension* belongs exclusively to Physics. The terms *time* and *number line* belong exclusively to Math and have nothing to do with Physics. The task of a physicist is to provide physical interpretations to the workings of the Universe. Neither time nor number lines can help elucidate or explain mechanisms.

#### And this takes us to the second major difference between a mathematician and a physicist. We simply apply Bernoulli’s blind, Lion’s Paw test

#### : “*tanquam ex ungue leonem*” *(essentially: “We recognize the lion by its claw.”) *A physicist is someone who can *explain* a mechanism. A mathematician can only *describe* it mathematically. And that’s all that time and number lines do.* *We have figured out all the visible mechanisms. What only physicists have been able to do is discover the invisible mechanisms of the Universe.

#### Physicists attempt to understand the workings of the real world. In the real world, there are only three dimensions, no fewer and no more. The three dimensions are known as *length, width*, and *height*. The only two properties that dimensions have are: direction and orthogonality.

*dimension: one of three imaginable, mutually-perpendicular directions in which an object may face or point*

#### When we speak of the world of 2-dimensional planes — or even when we talk about a single dimension such as width — we are implicitly referencing the other dimensions. There is no such notion in Physics as a single dimension all by itself.

#### Dimensions should never be confused with coordinates or with vectors, a very common error among mathematicians, again, a result of confusing number lines with coordinates and with vectors. Dimensions have to do with structure and orientation, coordinates with location, and vectors with motion. The following chart synthesizes these arguments:

**Time is not a dimension**

#### Many non-specialists are led to believe that time is a dimension. They later repeat this misconception without scrutinizing what they are saying. This ‘time = dimension’ misconception arises from the unscientific mathematical definition of the word *dimension*:

*dimension: the minimum number of ***coordinates*** **needed to specify any point within a mathematical set (collection of objects)* (Wikipedia)

*dimension: the number of ***coordinates*** needed to specify a point on the object *(Wolfram Mathematics). (As expected, Wolfram does not define the word *coordinate*. It defines the word *coordinate**s* [plural] as: ‘A set of variables’…)

*s*