Is time continuous or granular?

[Chaotic42]

My cousin and I are in disagreement.

He says that time is continuous. By this I mean that he thinks that there is no smallest amount of time. He admits that he has no evidence for his argument, except for intuition, which is good enough for me.

I say that it is granular, and here is why:

A) Space must be granular at some level (according to String Theory it's about 10^-33 cm). The reason is that if it weren't there would be infinitely strong forces at infinitely small distances. Even gravity would become powerful at 10^-999 cm. So whatever the minimim distance is, it's there. We'll say 10^-33 cm.

B) Assuming that A is true, the smallest amount of time that has meaning is the amount of time that it would take light to travel 10^-33cm, which is 3.33564095*10^-44 seconds.

What are your thoughts?

 

[CountZero]

Interesting idea but your argument for granularity of distance doesn't necessarily mean that there aren't smaller distances. If a string is 10^-33cm then it is in essence occupying 10 units of measure each 10^-34cm long (I'm just using 1 dimension as an example here, conceptually the idea is the same). Maybe such a distance is useless to talk about since you'd need to be on a scale of at least 10^-33 to see antying but that doesn't mean it doesn't exist. Also what if two strings overlap halfway, or a third would that violate the granularity?

Gravity can't be really stong at 10^-999cm because whatever causes the effect of gravity (gravitrons?) would be made of strings and therefore not able to fit into that small space.

In essence you are arguing that the light travels x distance in y time but if it traveled x/2 distance it will have done it in y/2 time. In order for light to travel some distance it must travel the points in between beginning and end, in your argument there are essential no distances smaller then x therefore light cannot be traveling through these points in between and would in fact be traveling faster then the speed of light due to the fact that it would in essence pulse from the beginning to the end instantly. Essentially time would tick on a very very small scale. But then light would be traveling instantly from one point to another.

Its an interesting idea but intuitively to me it doesn't seem right.

 

[Sahakiel]

Time is granular for one simple reason :
Assuming Relativity to be true, time itself can only be measured by the passing of an event. Since such processes require changes in energy, time is measured via changes in energy. Since energy is granular, time is granular.

On the other hand, I've heard arguments that time is measured by changes in entropy.

 

[glugglug]

Gravity IS really strong at 10^-999m. In fact, some have theorized that Gravity IS in fact the strong force that holds the nucleus of an atom together. Why isn't the static electrical replusive force even stronger on the protons? The reason given in this theory is that while electrical fields propagate at the speed of light, gravity propagates infinitely fast. Electrical fields are actually waves in fact, with a known frequency and wavelength that is several orders of magnitude farther apart than the nucleons. Essentially the protons are too close to feel the full effect of the electrical waves so that the electrical force overcomes gravity, until you have a ball of more than about 250 of them increasing their distance apart which is why all the elements that heavy are radioactive.

I would say time (and the other dimensions as well) are continuous, even though particles and energy levels are discrete.
The reason is this: How do you choose your x,y,z axis? Whatever set of axis you choose, you can take a pair of particles 1 unit apart on the x axis for instance, rotate one around the other 45 degrees and now have the vector between them be ~ (0.707,0.707).

 

[silverpig]

I vote for granular on the order of a planck time.

 

[Matthias99]

If it hasn't become clear yet, there is no good consensus on this issue, and any attempts to nail time down as either completely continuous OR discrete tend to lead to paradoxes. In fact, it seems an awful lot like the whole 'light as a particle/wave' phenomenon, but maybe that's just my impression.

See also: Zeno's Paradox(es), for one of the earliest serious discussions about the discrete/continuous nature of time and space. 'Achilles racing the tortoise' can be solved with integral calculus (so it's not really a paradox even if time/space are continuous), but the 'arrow in flight' one is more applicable here...

 

[Brucmack]

Originally posted by: glugglug
Gravity IS really strong at 10^-999m. In fact, some have theorized that Gravity IS in fact the strong force that holds the nucleus of an atom together. Why isn't the static electrical replusive force even stronger on the protons? The reason given in this theory is that while electrical fields propagate at the speed of light, gravity propagates infinitely fast. Electrical fields are actually waves in fact, with a known frequency and wavelength that is several orders of magnitude farther apart than the nucleons. Essentially the protons are too close to feel the full effect of the electrical waves so that the electrical force overcomes gravity, until you have a ball of more than about 250 of them increasing their distance apart which is why all the elements that heavy are radioactive.

I would say time (and the other dimensions as well) are continuous, even though particles and energy levels are discrete.
The reason is this: How do you choose your x,y,z axis? Whatever set of axis you choose, you can take a pair of particles 1 unit apart on the x axis for instance, rotate one around the other 45 degrees and now have the vector between them be ~ (0.707,0.707).

I checked out that page, but it doesn't make a whole lot of sense to me... I'm not a physicist.

However, I thought that the strong force was unique in that it increases is strength over an increase in distance until a certain boundary where it ceases to work anymore. So to fuse atoms together one must put the nuclei closer than this boundary. Simple hydrogen bombs have a spherical layer of a nuclear fission bomb on the outside of a tritium core, such that detonating the fission bomb compresses the tritium causing it to fuse.

On the other hand, gravity is a more normal force, decreasing in strength with distance. Can someone with knowledge explain how gravity could also operate in reverse at small distances? Or is this just a crackpot theory?

As far as the whole continuous vs. discrete argument, I think that there is basis for both arguments that everyone has made here. However, my vote is for continuous. Think of it this way... Even if time moves in really small ticks, is everything synchronized? I'll use Chaotic42's original example... Say that light moves that really small distance in a really small tick of time. Is all of the light in the universe synchronized so that they it all moves and stops at the same time? Personally I would think that things are able to move independently. Also, consider when two light waves move in slightly different directions... the relative motion would make the distances completely different.

In any case, this isn't something I'm going to lose sleep over, because I doubt computers are going to get down to those distances/times any time soon, and that's the only physics I would care about anyway

 

[Pudgygiant]

I'm going with granular. Not based on any physics, theoretical or otherwise. Completely hinged on the saying "the sands of time...".

 

[DrPizza]

Originally posted by: Brucmack

Originally posted by: glugglug
Gravity IS really strong at 10^-999m. In fact, some have theorized that Gravity IS in fact the strong force that holds the nucleus of an atom together. Why isn't the static electrical replusive force even stronger on the protons? The reason given in this theory is that while electrical fields propagate at the speed of light, gravity propagates infinitely fast. Electrical fields are actually waves in fact, with a known frequency and wavelength that is several orders of magnitude farther apart than the nucleons. Essentially the protons are too close to feel the full effect of the electrical waves so that the electrical force overcomes gravity, until you have a ball of more than about 250 of them increasing their distance apart which is why all the elements that heavy are radioactive.

I would say time (and the other dimensions as well) are continuous, even though particles and energy levels are discrete.
The reason is this: How do you choose your x,y,z axis? Whatever set of axis you choose, you can take a pair of particles 1 unit apart on the x axis for instance, rotate one around the other 45 degrees and now have the vector between them be ~ (0.707,0.707).

I checked out that page, but it doesn't make a whole lot of sense to me... I'm not a physicist.

However, I thought that the strong force was unique in that it increases is strength over an increase in distance until a certain boundary where it ceases to work anymore. So to fuse atoms together one must put the nuclei closer than this boundary. Simple hydrogen bombs have a spherical layer of a nuclear fission bomb on the outside of a tritium core, such that detonating the fission bomb compresses the tritium causing it to fuse.

On the other hand, gravity is a more normal force, decreasing in strength with distance. Can someone with knowledge explain how gravity could also operate in reverse at small distances? Or is this just a crackpot theory?

As far as the whole continuous vs. discrete argument, I think that there is basis for both arguments that everyone has made here. However, my vote is for continuous. Think of it this way... Even if time moves in really small ticks, is everything synchronized? I'll use Chaotic42's original example... Say that light moves that really small distance in a really small tick of time. Is all of the light in the universe synchronized so that they it all moves and stops at the same time? Personally I would think that things are able to move independently. Also, consider when two light waves move in slightly different directions... the relative motion would make the distances completely different.

In any case, this isn't something I'm going to lose sleep over, because I doubt computers are going to get down to those distances/times any time soon, and that's the only physics I would care about anyway

Not to mention, gravity also propogates at the speed of light per Einstein's general theory of relativity.

 

[CTho9305]

There was a pretty recent (late last year?) Scientific American article on this.

 

[PowerEngineer]

Originally posted by: glugglug
...The reason given in this theory is that while electrical fields propagate at the speed of light, gravity propagates infinitely fast...

You need better sources for sceintific information... Speed of Gravity

 

[glugglug]

Originally posted by: PowerEngineer

Originally posted by: glugglug
...The reason given in this theory is that while electrical fields propagate at the speed of light, gravity propagates infinitely fast...

You need better sources for sceintific information... Speed of Gravity

That experiment is flawed, as pointed out in other reports like this. Much like the other well published experiment last summer, they measured the speed of light not the speed of gravity, so of course it came out to be the speed of light.
You'll find a lot more that say the speed is a) unknown or b) at least 10^10c. Here's a couple: Text Text

There is a simple argument for how gravity MUST BE faster than light:

Gravitational fields cause light to accelerate, and a black hole is an area where the escape velocity to overcome this gravitational acceleration is greater than c. If gravity were the same speed or slower than light, black holes could not exist because the gravitational field of the black hole iteslf would never escape the black hole.

 

[sao123]

If gravity were the same speed or slower than light, black holes could not exist because the gravitational field of the black hole iteslf would never escape the black hole.

I dont believe your test is valid unless you have proof that gravity attracts itself. That seems more like a contradiction. Gravity is a disting (fluidlike) vector field. 1 complete continuous field, not distinct granular areas. If gravity could attract itself that sounds like pushing a boat by standing on it and blowing on the sail.

 

[RadBrad]

Time is continuous

There is not an expression of time that is less than zero or greater than zero that cannot be divided into a smaller part.

 

[silverpig]

Originally posted by: sao123

If gravity were the same speed or slower than light, black holes could not exist because the gravitational field of the black hole iteslf would never escape the black hole.

I dont believe your test is valid unless you have proof that gravity attracts itself. That seems more like a contradiction. Gravity is a disting (fluidlike) vector field. 1 complete continuous field, not distinct granular areas. If gravity could attract itself that sounds like pushing a boat by standing on it and blowing on the sail.

String theory provides for quantization of gravity...

 

[Roooooooooooooooooot]

No idea.

But that's a damn good question.

One perspective from my experience surfing intermediate size waves - during a wipe-out, when you're being pounded - if you can imagine yourself in that situation.

There you are going round and round. Eyes closed tight. Curled in the fetal position. Wondering, if you're so buoyant, how come you're not coming back to the surface ? Holding arms up over the head (advice from a guy that cracked a neck vertebrae because he forgot to hold his arms over his head.)

Like an underwater car accident, where you have to hold your breath.

Then you pop back up to the surface and, if you're REALLY strange, you think, oh, MAN !!!! That was FUN !

OK, so, during the actual apparent chaos of the wipe-out ~ how could time be anything BUT continuous ? If it was packetized, the universe would have to remember "where it put everything" ~ and that's a lot of f*ckin sh*t to have to remember where you put it. All those Billion^Billion water molecules.

Anyway, I'm impressed - not your ordinary deep thinkers here. Very entertaining. I'm coming back to this forum. That's not supposed to sound like a threat ;-)

Maybe one way to think about it ~ if there was a God, and YOU were God, how would you do it ? What would be SIMPLER ?

 

[gsellis]

Time is continuous. You are granular. Granularity is stuck in that same argument that was Zeno's Paradox. You want to express time as something you can keep spliting, but that is not how it exists. If it were granular, there would be no uncertainty. Heisenberg hints otherwise dare say?

 

[Pudgygiant]

Originally posted by: Roooooooooooooooooot
Maybe one way to think about it ~ if there was a God, and YOU were God, how would you do it ? What would be SIMPLER ?

Continuous would be much simpler. Think of it in terms of a runner. Continuous would be the equivalent of saying "run". Granular would be "run, stop every 5 feet, then continue running".

 

[LadyJessica]

I think most physicist agree that time is granular and that the smallest unit of time is planck time.

 

[LadyJessica]

There is a simple argument for how gravity MUST BE faster than light:

Gravitational fields cause light to accelerate, and a black hole is an area where the escape velocity to overcome this gravitational acceleration is greater than c. If gravity were the same speed or slower than light, black holes could not exist because the gravitational field of the black hole iteslf would never escape the black hole.

Of course in physics nothing is ever that simple nor do things really make a lot of sense. Who would have thought that there's a universal speed limit of c? Certainly not the people just 100 years ago.

 

[Roooooooooooooooooot]

Whoa !?! LADY Jessica !!! I will resolve to be a gentleman.

Actually, I think Deion Sanders had the right answer. "Both"

Most likely, the real answer is a paradox. Possibly (probably ?) beyond our comprehension.

But I do have a suggestion for a good activity to engage in, to prepare one's mind for the contemplation of such grandiose subjects.

Basically, any physical activity that makes time itself appear to accelerate/ dilate, and leaves the do-er extremely relaxed (so as to be in the proper state of mind with which to contemplate that which is difficult to comprehend.)

My personal suggestion ? Riding big waves. Specifically, the wipe-outs that occur when you're riding big waves. I can tell you for sure, your perception of time is drastically altered at such moments. Tenths of a second become like a second.

And, it's so much fun, I'm surprised the government hasn't made it illegal.

Plus, if you don't drown, you're so HAPPY when you get back to shore, that you realize the ultimate truth ... that these high-falutin subjects are not all-important, but still ... important ... if that makes any sense.

Then, when you're taking a hot bath afterwards, your mind is much better prepared for ... whatever insights occur.

Like ( in my case ) that the toilet needs cleaning.

Roger

equity@tns.com

Actually, it's tns.net

 

[Sahakiel]

Time should be quantized much the same energy and space are quantized. If you think the "splitting" argument is valid, I think you're going to have a problem with the fact that .999... = 1.