[thedoc (OP)]

Joash Hicks  asked the Naked Scientists:
   
Is there a Maximum speed for time? Is there a minimum speed for time? For example If I created an anti gravity machine and used it to make a pocket of space with no gravity would time be infinitely fast? Are there other things that affect the speed of time?

And as for the minimum, say I created a machine that could propel a clock with infinite acceleration as the mass approached the speed of like time would start to move slower and slower.

At some point would time be unable to go slower and I assume my machine would break the universe as it would then have to go faster then the speed of light.

What do you think?

[evan_au]

If you are in a deep gravitational well, time does go slower: on the surface of a neutron star, and to a much lesser extent on the surface of the earth.

The ultimate slowness is when the neutron star is on the verge of becoming a black hole, and time effectively stops.

To get your time to go as fast as possible, you need to get out of the gravitational well of the earth, out of the solar system, and out of our galaxy (and cluster of galaxies).

The formula can be found here: http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/gratim.html#c4

Presumably, as matter thins out due to expansion of the universe, places should appear that have even faster time...

Note that time is relative, so someone traveling past you, in deep intergalactic space would think your time was still slow!

[CliffordK]

I'm not convinced that "time" is actually variable, or what is being observed as variable. 

One of the problems of the "Space-Time" concept is that we seem to lack a good definition of time itself.

The current way that time is currently being scientifically measured and calibrated is as:

The oscillation frequency that maximizes the hyperfine energy transition detections of various elements.  This is calibrated to the element which is often cesium, rubidium, or hydrogen.

So, for example, at higher velocities, the elements seem to take lower EM energy (longer wavelength, lower frequency) to maximize the hyperfine transitions.

But, does that mean that time has slowed down, or just that the calibration for our frequency generator requires less energy?

It is unknown exactly how fast we are moving.  Current estimates are that the Milky Way is moving at about  550 km/s with respect to the cosmic background radiation (CMB), and the sun, due to its orbital velocity actually is only moving at about 370 km/s with respect to CMB.  So, if the CMB is actually in the zero frame, then the lowest intrinsic excitation of the particles, and thus the fastest measured time (by atomic clocks) would be an object that is distant from all major gravitational sources (Earth, sun, Milky Way), and moving away from Earth, in the direction opposite of Leo.

[imatfaal]

Clifford - the current thinking, and I believe the correct way of understanding this, is that time is dilated.  It is not that processes stall or take longer to complete it is that time is dilated.  Processes take the same amount of time in the rest frame always - but when viewed from another frame in relative motion, or at a different gravitational potential (or both) every single process, from a clock ticking (whether atomic or wind-up), to a beard growing, a muon decaying, bacteria multiplying and me typing appears to take place at a slowed rate.  Now we can either explain this as Einstein did by saying that time is dilated relative to the observer's frame, or we can introduce a panoply of rules about how each process, governed by different rules, and at various scales all have the same effect of of slowing the rate of process observed by the exact same amount.  I will take Ockham on this one. 

It is unknown exactly how fast we are moving.  Current estimates are that the Milky Way is moving at about  550 km/s with respect to the cosmic background radiation (CMB), and the sun, due to its orbital velocity actually is only moving at about 370 km/s with respect to CMB.  So, if the CMB is actually in the zero frame, then the lowest intrinsic excitation of the particles, and thus the fastest measured time (by atomic clocks) would be an object that is distant from all major gravitational sources (Earth, sun, Milky Way), and moving away from Earth, in the direction opposite of Leo.

We are not moving - I have declared my office the rest frame; we can of course tell how fast we are moving relative to...

Your paragraph seems to hint at the existence of a universal rest frame, a zero frame, where clocks are ultimately fast-ticking - this is not necessary and a contradiction to Special Relativity.  We do not need a zero frame and if we insist on imagining a privileged frame of absolute rest then we have to form some logical reason to create it.  SR works fine (and is logically sound) without it.

[yor_on]

Time is something happening, it has a beginning, well, for our thought up interaction (also called a causality chain). It has a 'now' in where you constantly exist as the interaction proceeds, and it will have a end as the interaction finish.

Time is something locally invariant. It will not change for you due to any speed measured, it will not change due to what mass you are on, as a Black Hole.

Time seems to belong to the room, meaning that time and the 'room geometry' goes together. Einstein called that concept SpaceTime, You might be able to turn that around and so assume that without a room, no time.

Time differs, between your local measurements/definitions and what you will define other positions in Space and Time to have.

What allow different 'frames of reference' aka positions in Space and Time to differ relative your local one is acceleration/deceleration, mass as in matter, 'energy density' per some measured space, and 'relative motion' as in Earths uniform motion through Space (and Time).

But locally time doesn't differ for you, it will give you the same life span no matter what you do, or where you go, never mind 'how fast' relative seen.
==

Forgot to mention gravity here, but to me mass, (uniform) accelerations/decelerations and 'energy' are equivalent ideas producing 'gravity'. Although all accelerations/decelerations to me, uniform or not, should produce it we most often refer to it as equivalent to uniform accelerations as that is how Einstein once  formulated it from GR.

[Emc2]

what I thought.

in reality "time" does not exist, it is only our way for describing the continuing expansion and existence of everything.

for time to really exist as something tangible, then it needs to be "made" of something, or it exists only as a concept to describe events and is not a thing made out of something.

 hence not being made of something = time is a concept and can have no speed.

 is that right ??

[yor_on]

Well, there's a problem there. We all die
And we all 'know' that time, or at least its arrow doesn't allow 'time travels' except in one direction, into the future. If time and the arrow is a illusion its very consistent, and those rules hasn't been broken yet, as far as I know. I don't think it is a illusion myself, it definitely exist.

[William McCormick]

Time is what you make of it. If this planet were spinning twice as fast as it does, eventually you would probably start producing and moving much faster, to get things done in a day. After a while a twelve hour day would seem normal. Plants would probably even adapt.

We can only judge time, by observing moving objects, that we assume, are always moving at some set rate. Change that rate, and you can be fooled. They have done experiments on humans and humans adapted to their new environments very quickly. Jokers at work playing with the clock have caused some laughs over the years.

Time is an illusion or noun created by the mind, based solely on the motion of matter or sub matter particles. It is not an object, device, or substance. It has no true provable laws or proofs to back up its existence, that I know of. All proof of time leads you back to the motion of matter. Which we call time. 



                      Sincerely,

                            William McCormick

[Emc2]

Well, there's a problem there. We all die
And we all 'know' that time, or at least its arrow doesn't allow 'time travels' except in one direction, into the future. If time and the arrow is a illusion its very consistent, and those rules hasn't been broken yet, as far as I know. I don't think it is a illusion myself, it definitely exist.

  I have to say, if "time" exists as something other then our perception,
then it has to be made out of something ?

  for a lot of our descriptions, growth, movement, advancement, expansion, etc. can all relate time as progression.

  time is just a word used to describe a lot of these things...

  until that "something" is found, I stand by, time does not exist as a thing, but as perception.

[yor_on]

In a way I agree. But the arrow is very strict. You can't go out and invalidate what get you born and what make you die by calling it a illusion. Because if you do you also invalidate all 'repeatable experiments' as they all follow that arrow. But what the arrow really 'is', and what makes it 'tick' for us is another thing where I'm in agreement with you both.

[Emc2]

I see time more as a way to describe something, rather then a thing.  For if it is a "thing", then it has to be made out of something, and without any "evidence" of what particles "time" is made out of,

 I have to say that "time" is only our way of describing - any progression, growth, expansion, etc. etc.

  A baby is born, it grows old, it dies.    we say that "time" passes, and speak of the "past", and the "future", but the past and the future, technically "do not" exist, they are concepts to describe events that in reality do not exist.

  so in truth, the only "time" that does exist, is right now, oops, too late, its already gone....lol..

   the only "time" that time does exist, is right now..  but that's just the present....and that's just another word..

just some thoughts..

 

[yor_on]

Not sure there. What we call 'bosons' are a lot of different things it seems, some measurable directly as 'photons', others only defined through the structures expressed in interactions, never measured directly. And then you have 'space' too, whatever that is

The Chinese used yin and yang as an expression, and tao lifts up the importance of 'space' for anything to exist.

[Emc2]

yes, a lot of it is in the "definitions" and explanations...

  to me if it is not "made" out of any particles, then it does not exist, but "time" may very well show that what we call "time" may be some sort of particle or wave function, stranger things have been found out....

 


 

[yor_on]

It's definitely connected to the room, well, if Einstein was /and still is/ correct that is. In that universe we have 'frames of reference' (SpaceTime positions) in where you are the definer of all other 'frames of reference', and if I'm 'assuming' right there the definition of a SpaceTime position has to be made somewhere around Planck scale. So 'times arrow' as a expression is your local rigid definer of what time you will have, nota bene, locally that is

And the only way your 'clock' ticks is from a locally invariant perspective to me. It's somewhat ridiculous as I see it mixing that with comparing other 'frames of reference' and saying that 'because I'm moving so fast I'm going to live forever' That's not true, the universe, as it all consist of those different 'frames of reference', may change faster for you looking out, but your life span will locally be the exact same as I see it.

[yor_on]

Well, more or less that is 'the same' as if we define it to Planck scale must consider both time dilations and LorentzFitzGerald contraction acting between those positions, at least from accelerating frames, as each position then should 'deform/distort/dilate' relative the next 'frame of reference'. But we have measured gravitational time dilations at centimeters without our bodies finding them hard to take so I will presume the same to be true for LorentzFitzGerald contractions too, also as presumed by 'gravitational waves'.

[Emc2]

time is relative to the observer, and just as growth and aging are.  Just as something growing or expanding is said to "age" as time passes, sometimes at work time fly's for me, and yet my one co worker can say it dragged on for them.   I have been in combat and have had time "slow" down" so much, things actually seemed like they were going slow motion, and at other times things happened so fast, that when it was over, I really didn't know exactly what happened.

  time you could say is equal to "perception" or 'observation", nothing more, nothing less.....

[yor_on]

That's true E.
The mind can do all sorts of things, slow 'time' down, or speed it up. The time I'm referring to above is the 'objective' 'local time' for interactions but then we have the minds treatment of it. It might be clearer to see how I think if you consider the idea of repeatable experiments. Science builds on the concept of us being able to repeat experiments, for a theory to be considered valid you need to be able to repeat my experiment and confirm it for yourself. And all experiments involve time.

If now your local experiment would differ from mine, by size (the local ruler), or by time (the local clock) you would get another answer than me and so call the experiment into question. But we don't find it to be so, we can all do the experiments locally and find them repeatable. That's the type of 'local time' I'm referring too. But then we have the minds treatment of the same, and that's another thing to me. Almost 'mystical' at times

[Emc2]

yes, our experiments would yield the same results, but I believe that is because there is a global accepted calculation used.

   we base our description of "time" measured by the spinning of the planet and the cycle of day and night, 24 hrs, and divide that out to get frames of reference that "all" can "relate" to, of course if you live in another galaxy on another planet, your reference of time, is according to your observations and perceptions. but here If I say I'll meet you in say 5 hours, you have a reference for that to relate to, the amount that the earth spun and/or rotated, and by visibly looking at the light , darkness of the sky.  The days and months and years, are all based on orbital cycles, but is all of this really "time" ?

 

  It may very well be, as I stated before in order for "time" to actually be a "thing", then it has to be made out of something, or else it is only a word used to describe an observation or perception, and I am not saying that it is not made out of something, only that said something has yet to be found, until then, to me it is only perception and observation using orbital movements as points of reference and calculation....

 

[yor_on]

When you think about this it will take you time, and as you do it particles interact and new ones are 'born'. All of this is referred to as 'time & its arrow' allowing it to happen. The best I can get to time is that it must be connected to the room we are in, and 'motion' and 'mass-energy' in that same room. We stipulate that 'energy' alone can act as a gravity, and so we also stipulate that this 'gravity' if Einstein is right, and so far he has been shown to be, must act as a definer of clock rates (relative the observer). That means to me that if there could be something of a immense 'energy', not that I see how it would exist without transformation, then we also can stipulate a beginning of 'time' there. I think you are right in that 'time' is 'something' but to me it seems to be a constituent of SpaceTime, and not really able to be 'split out' of that idea.

[Emc2]

lol

  only "time"  will tell.........
  what time is.......