Time

[Juma]

Regardless how we define distance and time, the two are linked.To move a move 1 meter requires time.

Until Albert's bombshell space and time were thought to be fixed. The key is to realize there are no absolute reference points. We can only measure something as a difference to an arbitrary reference. A 5 pound bag of potatoes is relative to the mass standard, a chunk of metal in a lab.

It's worse than that even... it actually takes an infinite amount of time to move 1 meter.... because, before you can possibly move 1 meter, you first have to move 1/2 meter... presumably, that will take half the time. Before you can move across the second half of that meter, you will first need to make it halfway... another 1/4 meter... that will take another quarter of the time.... since you can infinitely divide the distance to travel in half, and still have half of the last interval to travel, you can really never get anywhere in this universe!

I assume that you know that the sum of all these timespans is as finite as the distance travelled...

 

[fast]

Time is a clock. If not, then define what you mean.

Time is a fart in the wind....

Way back in the 90s I rode a motorcycle when I lived in Portland Or. I liked to ride on Sauvie Island,' As I accelerated the centerlines blurred, at around 70 mph on a long straightaway my perceptions went into a slow mo mode. I could clearly see each line as I passed.

One day I entered a curve I had done many times. I noticed I was going sideways, gravel on the road. I watched the spill develop in slo mo detail. Right out of a movie slo mo. Perception of rate of change is a function of our physical brains. as is our consciousness.

As to clocks, all things mechanical and electrical vary with temperature. That is not relativity. The accuracy of a quartz based clock is relative to the national time standard.

Time isn't the clock. The clock is the measuring tool.

The runner ran a mile. How long did it take? In other words, how much time did it take? What was the elapsed time from getting from start to finish? It took four minutes.

The clock measured something, for it's a time keeping tool. It isn't time. It tells us the time.

If the runner takes off at 1:00 and God presses pause on the movement of all things for 20 seconds, then the elapsed time will be 4m20s, which is what would be shown if he allowed the clock to continue while all else was paused. Time continues even when movement doesn't--and it's a steady rate

 

[Juma]

Time is a clock. If not, then define what you mean.

Time is a fart in the wind....

Way back in the 90s I rode a motorcycle when I lived in Portland Or. I liked to ride on Sauvie Island,' As I accelerated the centerlines blurred, at around 70 mph on a long straightaway my perceptions went into a slow mo mode. I could clearly see each line as I passed.

One day I entered a curve I had done many times. I noticed I was going sideways, gravel on the road. I watched the spill develop in slo mo detail. Right out of a movie slo mo. Perception of rate of change is a function of our physical brains. as is our consciousness.

As to clocks, all things mechanical and electrical vary with temperature. That is not relativity. The accuracy of a quartz based clock is relative to the national time standard.

Time isn't the clock. The clock is the measuring tool.

The runner ran a mile. How long did it take? In other words, how much time did it take? What was the elapsed time from getting from start to finish? It took four minutes.

The clock measured something, for it's a time keeping tool. It isn't time. It tells us the time.

If the runner takes off at 1:00 and God presses pause on the movement of all things for 20 seconds, then the elapsed time will be 4m20s, which is what would be shown if he allowed the clock to continue while all else was paused. Time continues even when movement doesn't--and it's a steady rate

That pausing didnt make sense: if everything actually stopped then they would have speed 0 when god pressed ”continue”. Or did you mean that everything kept there speed and just continued in the same trajectories afterwards?

 

[Treedbear]

It's worse than that even... it actually takes an infinite amount of time to move 1 meter...

Tell it to this guy:
View attachment 13175

They might move faster if they were converted to feet.

 

[fast]

Time is a clock. If not, then define what you mean.

Time is a fart in the wind....

Way back in the 90s I rode a motorcycle when I lived in Portland Or. I liked to ride on Sauvie Island,' As I accelerated the centerlines blurred, at around 70 mph on a long straightaway my perceptions went into a slow mo mode. I could clearly see each line as I passed.

One day I entered a curve I had done many times. I noticed I was going sideways, gravel on the road. I watched the spill develop in slo mo detail. Right out of a movie slo mo. Perception of rate of change is a function of our physical brains. as is our consciousness.

As to clocks, all things mechanical and electrical vary with temperature. That is not relativity. The accuracy of a quartz based clock is relative to the national time standard.

Time isn't the clock. The clock is the measuring tool.

The runner ran a mile. How long did it take? In other words, how much time did it take? What was the elapsed time from getting from start to finish? It took four minutes.

The clock measured something, for it's a time keeping tool. It isn't time. It tells us the time.

If the runner takes off at 1:00 and God presses pause on the movement of all things for 20 seconds, then the elapsed time will be 4m20s, which is what would be shown if he allowed the clock to continue while all else was paused. Time continues even when movement doesn't--and it's a steady rate

That pausing didnt make sense: if everything actually stopped then they would have speed 0 when god pressed ”continue”. Or did you mean that everything kept there speed and just continued in the same trajectories afterwards?

Your latter explanation. A two hour movie takes two hours 12 minutes to play from beginning to end when the reel breaks and it takes 12 minutes to fix.

 

[steve_bank]

As an engineer to be technical a clock is anything that provides a periodic reference. It used to be a sidereal day divided down to a second. It can be mechanical, chemical or electrical. Dilation applies to a water clock or hourglass or cuckoo clock.

A counter counts the number of clock iterations over an interval to derive time duration. Scientifically time is a duration expressed in seconds.

Start substituting duration or change for time. The word time is subjectively loaded from all the scifi.

 

[fast]

As an engineer to be technical a clock is anything that provides a periodic reference. It used to be a sidereal day divided down to a second. It can be mechanical, chemical or electrical. Dilation applies to a water clock or hourglass or cuckoo clock.

A counter counts the number of clock iterations over an interval to derive time duration. Scientifically time is a duration expressed in seconds.

Start substituting duration or change for time. The word time is subjectively loaded from all the scifi.

I'm okay with, "scientifically, time is a duration expressed in seconds."

The "expressed in seconds" part, however, is extra and unnecessary. Helpful, very helpful, however.

We cannot have an event without time, so you might even say that time is the duration of an event expressed in seconds, but the event too is extra and unnecessary, although we cannot have an event without time, we can have time without an event. We couldn't measure time without an event in the whole universe, but the dimension of time can be what it is without the measuring and expressing that would be absent with no event.

Consider the following thought experiment:

There are exactly five planets. Planet A freezes every other year, so in (let's say) year 3001, the planet is completely normal but completely frozen in 3002, Normal again in 3003. Frozen in 3004. And so on.

Planet B is normal for two years and then frozen for two years and the cycle repeats.

Recap:
3001 (planet A normal) (planet B normal)
3002 (planet A frozen) (planet B normal)

3003 (planet A normal) (planet B frozen)
3004 planet A frozen) (planet B frozen)

At this juncture, we can still tell time because there are more planets whereby there is movement. Planet C has the rhythm normal normal normal frozen frozen frozen, so while planets A and B are both frozen in 3004, we don't deny the passage of time during the year 3004.

I could break this down a lot more if needed

 

[steve_bank]

When I say scientifically I mean SI basic units. The SI second is now the international time standard for all things. Beyond that debate inevitably descends into semantics and metaphysics, exactly what SI avoids.

We observe movement, the second is how we quantify change. Define what you mean by time.

Ancient Zog wants to see who is the fastest runner in the tribe. As each runner runs a course a drummer keeps a beat. On each drum beat a timekeeper drops a pebble into a bucket.. A clock and counter.

 

[Speakpigeon]

Start substituting duration or change for time. The word time is subjectively loaded from all the scifi.

I doubt that 'change travel' or 'duration travel' will ever catch up.
EB

 

[fromderinside]

It's worse than that even... it actually takes an infinite amount of time to move 1 meter...

Tell it to this guy:
View attachment 13175

They might move faster if they were converted to feet.

...or moved to yards.

 

[Malintent]

Time is a clock. If not, then define what you mean.

Yes. Time is a clock. To refine what I mean by that:

Time is the ratio between Velocity and Displacement.

 

[Malintent]

Regardless how we define distance and time, the two are linked.To move a move 1 meter requires time.

Until Albert's bombshell space and time were thought to be fixed. The key is to realize there are no absolute reference points. We can only measure something as a difference to an arbitrary reference. A 5 pound bag of potatoes is relative to the mass standard, a chunk of metal in a lab.

It's worse than that even... it actually takes an infinite amount of time to move 1 meter.... because, before you can possibly move 1 meter, you first have to move 1/2 meter... presumably, that will take half the time. Before you can move across the second half of that meter, you will first need to make it halfway... another 1/4 meter... that will take another quarter of the time.... since you can infinitely divide the distance to travel in half, and still have half of the last interval to travel, you can really never get anywhere in this universe!

I assume that you know that the sum of all these timespans is as finite as the distance travelled...

ya.. 1 = {1/2 + 1/4 + 1/8..... 1/n}

but it's fun to throw that out.. some people get a kick out of expressing an infinite set as a finite constant.

 

[fast]

Time is a clock. If not, then define what you mean.

Yes. Time is a clock. To refine what I mean by that:

Time is the ratio between Velocity and Displacement.

Time is more like the passage of seconds. A perfect clock will tell us that a second has passed when and only when a second has passed. An imperfect clock will inaccurately state when exactly a second has passed.

 

[Malintent]

Time is a clock. If not, then define what you mean.

Yes. Time is a clock. To refine what I mean by that:

Time is the ratio between Velocity and Displacement.

Time is more like the passage of seconds. A perfect clock will tell us that a second has passed when and only when a second has passed. An imperfect clock will inaccurately state when exactly a second has passed.

OK. In this context, what does "passage" mean?

 

[Treedbear]

Time is a clock. If not, then define what you mean.

Yes. Time is a clock. To refine what I mean by that:

Time is the ratio between Velocity and Displacement.

You can refine it even further:
Time is the ratio between Velocity of Light in a vacuum and Displacement.

 

[beero1000]

Round and round we go...

 

[fast]

Yes. Time is a clock. To refine what I mean by that:

Time is the ratio between Velocity and Displacement.

Time is more like the passage of seconds. A perfect clock will tell us that a second has passed when and only when a second has passed. An imperfect clock will inaccurately state when exactly a second has passed.

OK. In this context, what does "passage" mean?

The elapsed moment between the boundaries of the second.

If the clock stops, the problem isn't with time. That would be a problem with timekeeping.

If a clock slows down, that's because of forces on the clock. If we're not careful, we'll think time has slowed down when it's not time that is the problem but the forces on the clock.

 

[Angry Floof]

77 replies and no mention of wibbly wobbly timey wimey stuff?

 

[lpetrich]

There is another aspect of time that's worth mentioning. Time has a well-defined direction only if there is only one time dimension. If there was more than one, then it would be possible to go in circles in time.

In our universe, there are five classes of vectors:

• Forward timelike
• Forward null
• Spacelike
• Backward null
• Backward timelike

while for more than one time coordinate, one finds only three:

• Timelike
• Null
• Spacelike

Forward: time component positive
Backward: time component negative

Timelike: its magnitude has the sign for the case of only time components nonzero.
Spacelike: like timelike, but with time and space interchanged.
Null: zero magnitude.

 

[steve_bank]

I'd argue that time has no direction. The observable universe is constantly changing.

Time is s simply a measure of change.