What is time?

[EWright]

Originally Posted by alxian

that beacon, if it were not accelerating and if it could compensate for the pull of local galaxies (should their magnetic influence overlap to neighboring galaxies) and anomalies would represent as close to perfect "time" keeping we could hope for. if we had ansibles (FTL communications) to communicate with it, and a need to keep perfect universal time, then several such clocks could keep several local systems synchronized.

If we had FTL communication, we wouldn't need relativity, now would we?

[C1ay]

Time is the chronology of nature.

[Southtown]

If clocks are subject to physical laws (and they are) and clocks measure time (as they are said to) then time cannot be used in physics (circular reasoning) only deduced from physics.

“The issue which is being avoided by every physicist I have ever met is that, "clocks do not measure time"! Not if interaction between two entities requires that they exist "at the same time". Physicists set up a coordinate system as if time is a measurable variable, deflecting attention from the fact that it isn't. Time is a deduced variable, very convenient to the description of physical phenomena, but deduced none the less.” — DoctorDick

http://www.physicsforums.com/showthr...560#post196560

[alxian]

indeed time is something we create to understand a universe that never had a like concept. so much of our understand comes from such fudgings but where would we be without them?


of course we would

FTL in fiction is divided into two groups, commmunication of information and communication of matters streams

as long as FTL is only capable of transferring data as in the now defunct theory of quantum entanglement you will be stuck with moving matter around in accordance to a universe and its physical laws.

if you can however use FTL to travel, turning matter into energy and syphoning that energy "somehow" from here to there and then reconstitute that energy stream, you'll still need to be mindful of where you end up.

if the gravity is several times stronger than your origin you'll be soup on the recieving alter.

if the gravity is far less you'll crack your skull on the ceiling trying to walk off the recieving alter.

i was just thinking about stargate and why the event horizon wasn't just a clear film showing there, but figured they just didn't have the budget or thought it would be more dramatic for the event horizon to be flowmetal-like (water like in the movie).

your body has its own internal clock, if you jumped through the gates event horizon and ended up in a place highly accelerated (which slows time) by gravity and you did survive (having trained for weeks or months before, or having modified your physiology to compensate for the change in gravity) your body would still feel the subtle effects of the timeshift. everything would be subtly slower or faster, you'd suffer timelag.

even if you travelled back and forth constantly, commuting, passing between several similar gravity fields you wouldn't notice any difference at all.. however i think subtle sideeffects would eventually surface.

i think amoung some of the fundamental flaws of the show that has to be a big one. gravity is not the same everywhere, regardless of how meticulous the ancients were there must have been planets that warranted exploration and exploitation that weren't earth normal, this greatly expands their realm as so many planets must have been ignored (nevermind how they even got to those thousand of other near earthlike planets in the first place, or how our decendants will).

[emessay]

1. ................Once upon a Time............ =............. Once upon a Space................
2. Then a philospher said : "Space tell time how to travel and time tell space how to curve".
3. I speculate that space-time is related function to life-clock based on logical time comparison : space required 11-13.7 bya and life-clock required 3.8-4.5 bya.

[Qfwfq]

Time doesn't exist!!!!

L. De Crescenzo, Neapolitan amateur philosopher and commedian, proved it with an astoundingly simple argument:

Time is dividible into past, present and future.

Past is what no longer exists. Therefore it doesn't exist.

Future is what doesn't yet exist. Therefore it doesn't exist.

Present is nothing but the border separating past and future, an evanescent nothing but where two contiguous entities meet. As both these entities don't exist, neither can the border between them, as it is nothing else than such. Therefore it doesn't exist.

Therefore past, present and future don't exist, so time doesn't exist.

Originally Posted by C1ay

Time is the chronology of nature.

Equals:

Time is the "discussion of time" of nature...............

[xersan]

Tıme is a dimension like other length dimensions. Because it is measurable and dimension of time defines one of coordinates. Besides ıt determınes the period of event or the moment of event.

But our clocks have standart pulses for every condition. The clocks are neverbecame slower or faster by the theory SR. If tempo of time can differ because of any reason, the clock can not show ıt. For example the perıod of day is became small, the clock show forward.

[Jay-qu]

I think it was Einstein that once said that 'the passage of time is only an illusion even if a stubborn one!'
all time exists at once in space-time.. - when thinking about time you have to let go of common sense, if you listened to common sense you would believe that the sun orbits the earth!

[Southtown]

Originally Posted by CraigD

His affection for a universe consisting of 10^68 pre-rendered, unchanging copies of the observable universe bears an uncanny similarity to his affection for pre-rendered pages of Apple 2 color graphics.

On some level, he does recognize it. Somehow, it just didn’t feel wrong.

Bravo! HAHAHA! Brilliant! I can't believe I missed that, thanks CD. Reminds me of another smart physicist's philosophy:

“Imagination is more important than knowledge.” — Albert Einstein

Who's to say it's not true? HAHA One thing is for sure: the attempted contemplation of time stretches the consciousness to its limit. Time perhaps even defines consciousness. Time, gravity, and matter/energy will probably all be defined at once.

Originally Posted by Jay-qu

when thinking about time you have to let go of common sense, if you listened to common sense you would believe that the sun orbits the earth!

What?! Why exactly is that? Didn't the "age of reason" bring an end to such ideas?

[CraigD]

Originally Posted by xersan

Tıme is a dimension like other length dimensions. Because it is measurable and dimension of time defines one of coordinates. Besides ıt determınes the period of event or the moment of event.

... with (at least) one critical distinction: with a modest amount of work, I can rotate a physical object (such as the stylus I'm writing this with) so that its "length" is now its "width" or "height" - that is, apply rotational coordinate transform to all of its points.

I can't rotate it in a way that effects its time coordinates. For example, I can’t manipulate it in a way that swapps its time coordinate for its north-south coordinates, so that my old stylus becomes longer, or newer. *

Treating time as a dimension is very useful, but the time dimension is not like a spatial dimension in the way a one spatial dimension is like another.

* A stickler for details might point out that I actual can do something like that by giving it a velocity – according to Relativity, Fitzgerald length contraction can be described as a rotation in the 4 dimension of Minkowski space - but this isn't at all like rotating it about its 3 spatial dimensions. A "90 degree" rotation, which requires a tiny amount of energy about the 3 spatial dimensions (and doesn't involve my stylus flying off into the great beyond!) would require an infinite amount of energy when done about the time dimension.