h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

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No.

Time and space measure the rate of propagation of change through "stuff" (energy), but these three "things" (energy, time & space) are all measured in terms of each other (General Relativity), using the speed of light as a synchroniser.

Noggin

Then if the speed of light is the synchroniser as you describe Noggin, and speed is measurement of time taken ( or interval) between the emanation from a source and the reception some distance away, are the speed of light and time linked as if one?

Granted the perceptions of time are human interpretations of events rather than 'actual'.........

Novo

To be honest, I'm a bit out of my depth here. But the essentials are that time, space and energy are all measured in terms of each other. The speed of light, however, is constant for all observers in all reference frames. The implications are the basis of relativity.

Noggin

Hi Nog,

If you're out of your depth then I'm treading water over the Marianas Trench with a lead poncho but I'll throw in my two cents regardless.

As far as time being measured, that's just our perception of it, isn't it? The speed of light may be constant but it's just how we look at it, not what it is. It's our physical framework to measure something we perceive in our own particular way. An energy being from a whole different universe or someone who is present for the Big Bang could *see* and *measure* it in a completely different way, no? So the time it takes for light to travel a certain distance in our framework need not be the same measurement in another, but they would be the same. If the concept of time and distance was alien to something or someone then perhaps they would measure frequency as taste, distance as colour or time as speed.

Does that make any sense whatsoever?

Well, wether you measure frequency as taste or not you´d presumably get the same values.

"are the speed of light and time linked as if one?"
Well as Einstein showed space and time are linked. The way you move through space changes the way you move through time. And that does seem to depends on the speed of light.

So, what's the speed of dark?

The same I guess !

If you switched off a star the period of time to the absence of light would be the same as if it's light was still emanating. wouldn't it?

I have always thought that atomic decay. as in Uranium 238 to 235 ( half life I think ) is the true measure of a unit of time because it is surely always the same, and not open to human perception, or alian perception, come to that.

Novo

>>
kea can you name the cultures that experience time non-linearly so that we may research them?
<<


Pretty much any culture that is land based and hasn't historically used clocks. Ones I can think of off the top of my head are Maori, Australian Aboriginal, any of the Native American cultures etc.

If I get the time I'll dig up some links

This looks interesting, about the Sami concepts of time:

http://www.utexas.edu/courses/sami/dieda/anthro/time.htm

Haven't read all of that yet, but so far I haven't seen anything that would suggest that there are cultures that *experience* time non-linearly, or even that any sense can be made of that claim. Perhaps you mean "conceptualise" rather than "experience"? After all, in this post-Einstein age we conceptualise space as curved, but continue to experience it as flat.

Noggin

Don't we in the West conceptualise linear time AND experience it?

Maybe it's to do with that article being from an academic source. If you talk to indigenous people directly, or read what they write directly, then they are talking about experience not just conception.

I'd have to think about this more, but I'm tempted to say that even that approach of seeing concept and experience as being so separate is culturally specific, and that not all cultures operate that way.

I'm still not quite sure what you *mean* by a non-linear experience of time. *I* mean unidirectional, as described above.

Noggin