Is it possible to break down time from 1 second to 1 millisecond, to 1 nannosection, etc, until you can't break it down any further?

Not according to any mainstream physics I was aware of. The time coordinate is considered as real-valued in all models I have encountered (*). Strictly speaking that of course is only a choice that works well on all accessible scales (say from picoseconds to a few billion years), and that outside this scale things could be different. Over the years my attitude towards such things has become "possibly - but why should I care?".

 

(*) That is not correct. I have encountered many models with integer-valued time (e.g. a calendar). But in all those cases it was clear that the discrete time is only an approximation to simplify things, not a correction.

There is a notion of Planck time (~10^-43 sec.). There are questions about whether going any smaller is physically meaningful (Of course mathematically there is no limit).

There is a notion of Planck time (~10^-43 sec.). There are questions about whether going any smaller is physically meaningful (Of course mathematically there is no limit).

 

There is also a notion of Planck length, and just as much rank speculation in the popular literature.

 

All currently accepted theories, including quantum field theories, model spacetime as a manifold which implies no minimal unit for either space or time. Any statements to the contrary are pure speculation. Attempts to formulate discrete models have not, thus far, been successful -- but people are still trying.

 

That said, no one really has a clue what happens at the Planck scale.

 

 

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Time as of yet is only what we make of it. Although we can measure time to miniscule lengths, it is still an entity that can be split an infinite amount if times, so short that something even on a quantum level may not even occur.

There is also a notion of Planck length, and just as much rank speculation in the popular literature.

 

All currently accepted theories, including quantum field theories, model spacetime as a manifold which implies no minimal unit for either space or time. Any statements to the contrary are pure speculation. Attempts to formulate discrete models have not, thus far, been successful -- but people are still trying.

 

That said, no one really has a clue what happens at the Planck scale.

 

 

If you like this post, punch timo's "+" button.

Lee Smolin's Three Roads to Quantum Gravity suggests that both Quantum Loop Gravity and String Theories require discrete time. No danger of experimental verification of any of these speculations any time soon of course. But the quest is a noble one.

Yeah, Planck Time, as others have noticed the answer.

There are various notions of the chronon, which is a "quanta of time". This is outside of standard accepted theory, but I think that on some level combining quantum mechanics with general relativity would produce some notion of quantised time.

Oh the Chronon... now there is a name I have not heard in a while. This number has possible massive implications for quantum mechanics. The Chronon is a wonderful idea.

If we consider the Heisenberg Uncertainty Principle as it relates time and energy, we find that as the time increments get smaller ( more exact ), the allowed energy excursions become larger and larger. In effect, extremely large amounts of energy can be localised in an exceedingly small volume of space for an infinitesimal amount of time. I don't have time to do the math right now, but I believe this could be a limiting factor to infinitely subdividing time increments, and so, may imply a minimum limit.

Lee Smolin's Three Roads to Quantum Gravity suggests that both Quantum Loop Gravity and String Theories require discrete time. No danger of experimental verification of any of these speculations any time soon of course. But the quest is a noble one.

 

Lee Smolin has suggested a lot of things.

Insteaf of Planck time, how about an even smaller interval that might matter? How about the distance it takes for a photon to travel from one quark to another quark?

A hadron is of the order 10^-15m so a photon or perhaps more likely a gluon will take far longer than the quark time to cross it. The planck time is the time for light to transit one planck length - one planck length is 10^20 times smaller than a hadron! The planck time is exceedingly short

Well, from what I know is the smallest producable time (at the moment) will be at the Europeen XFEL. They will be able to produce "laser" pulses with 100 fs (10^-15 s) puls length and the photon packages have a distance of 0.3 fs. From what I know this is the smallest measurable time yet.

Edited December 3, 201114 yr by Roentgenquantum

I'm seeing tons of scientific terms but surely the easiest way to explain it would be the shortest length of time in which any change can happen. However, if you're trying to separate time into frames you're gonna have to solve the problem of continuous changes, such as motion.

Planck time assumes that,the vacuum of space is a matrix,like a 3 dimensional chess board,planck time being the time it takes to move from one square to the next.Except that in 3 dimensional space the squares would be individual oscillators.

So you would have a minimum planck time and a minimum planck distance,motion would occur in ultra fast steps.

 

Planck time being 10^-43 seconds.

However the smallest time step measured is 12 x 10^-18 (10^24 x Planck time).

Edited January 6, 201213 yr by derek w