This is an interesting article, new research suggests that measurements of time are not measurements of a dimension but of the numerical order of events in space:

"The concept of time as a way to measure the duration of events is not only deeply intuitive, it also plays an important role in our mathematical descriptions of physical systems. For instance, we define an object’s speed as its displacement per a given time. But some researchers theorize that this Newtonian idea of time as an absolute quantity that flows on its own, along with the idea that time is the fourth dimension of spacetime, are incorrect. They propose to replace these concepts of time with a view that corresponds more accurately to the physical world: time as a measure of the numerical order of change."

http://www.physorg.com/news/2011-04-scie...nsion.html

Numerical order of things seems to be an artifact of the perception of time, and does not address at all the fundamental nature of time. Why for example do the numerical order not count backwards? What explains why appearently truly random events like radioactive decay is still perceived as an ordered series of events?

Not so sure about this really. Maybe because it's always that I've considered time to be a dimension that we are travelling through that was created by the big bang and is still expanding like the other dimensions, also, there are quantum particles, that 'borrow' energy from their future selves. i.e. they suddenly get a ton of energy from nowhere, do something with it, and then later 'give it back'.

It works out only if you consider time to be a dimension that such particles can traverse.

I don't know... I'm still trying to wrap my head around the idea.

It seems that their argument is one of semantic: replace 3 spatial + time by 4 spatial. However, if it is more than that, I would like to see what it is that they are suggesting. We know that in the Lorentz transformations, time and space get mixed up, yielding length contraction and time dilation, which are two phenomena that have been observed. We also know that QFT requires that the Lagrangian be Lorentz invariance. So the concept of 3D + T is deeply ingrained into the theory.

Like I said, if it is just semantic, then it's no big deal.

This is something I've always suspected.

Since all of the effects of light speed travel( time dilation etc) could be explained as purely subjective, therefore time ceases to be a dimension as such and just becomes a side effect of stuff happening.

Subjective?

Subjective generally means "Grounded in the opinions of persons".

How is a mathematical prediction, experimentally verified, subjective?

I mean subjective inasmuch as the effects of time dilation only apply to the person in question.

Not to time itself.

(May 9, 2011 at 7:27 am)Zen Badger Wrote: This is something I've always suspected.

Since all of the effects of light speed travel( time dilation etc) could be explained as purely subjective, therefore time ceases to be a dimension as such and just becomes a side effect of stuff happening.

Sorry to disagree, but time dilation is not subjective: it can be measured in the half-life of a muon from cosmic rays. And it is being used in GPS in order to give it a 2 m accuracy in locating any position on earth.

How does this tally with time altering with speed?