Assertion of an "absolute now" from "What is 'spacetime' really"

[Boof-head]

Clocks measure their own internal changes of state

No, they don't.

Clocks don't measure a thing; we just tell ourselves "clocks keep track of time", but this isn't really the case, we keep track of time, by looking at a clock, or listening to a talking clock, or seeing where the sun is or how dark or light the sky looks.

 

We're the measurers, measurement isn't something inanimate matter is capable of.

[Essay]

Clocks measure their own internal changes of state.

Yes, and so couldn't we just talk about reality, instead of clocks?

 

Clocks measure reality (their reality). Am I wrong to say that it is reality that slows down in a higher gravitational field? Atomic decay events (clocks) on our GPS satellites are speeded up (as are chemical reaction rates) due to the lower gravity.

 

 

p.s. [i think I recall this correctly] Overall, there's a net slowing of reality on the GPS satellites, due to the velocity--which outweighs the "speeding up of reality due to low gravity" --but that's another part of the equation.

[modest]

I would not be so tempted. Magnetic fields are obviously curved.

Spacetime is obviously curved in the presence of mass.

The Earth's... a bar magnet's... solar flairs... the aurora borealis. We can see the curvature as expressed by iron filings on paper over a magnet... or in the display of ionized gases near the poles.

We can likewise see curvature expressed by earth, mars, mercury, comets, light—and all other paths made through the solar system or galaxy.

the curved force field of magnetism does not establish "The Curvature of Space."

Indeed—magnetic field lines are curved in flat spacetime.

It is a "fabricated medium"... only a model... unlike magnetic force fields and curved light paths.

Magnetic field lines represent a vector field and should not be reified. In a similar way, the dimpled depictions of spacetime like a bowling ball on a rubber sheet that you see in textbooks represent a tensor field and should not be reified.

Pyrotex: "I love the analogy between "time" and "ley lines".

Modest:: "I like it too. I think it was originally brought up in post #137:"

 

 

 

Your magnet example completely misses my point... as usual. (as per my above comments.)

My magnet example did not address your point. It was neither a response to it nor a response to you. I will, however, address it now.

A brief exercise in logic...

Assertion: "Time is what clocks measure." (Implication: If clocks measure "it" then "it" must be "real" (as an entity of some kind.)

In special and general relativity space and time are what clocks and rods measure. That is the definition of time in those constructs and so too is it the definition I've given. It's also, incidentally, a definition I'm rather fond of. It is simply a definition, not an ontological element.

 

Your stated implication that "time is what a clock measures" somehow advocates the idea that time is an entity of some kind (presumably an ontological entity) is not an implication I've made. I've simply defined the terms I'm using.

 

Incidentally, there is no significant difference between my definition of time and yours:

Time is essentially duration (which we might think of as being measured with a clock or any regularly repeating phenomenon)

 

post #590

Time is the *concept/measure* of event duration, like... one rotation of earth... one earth orbit around sun... the great cycle of the precession of the equinox...

 

post #576

So you might just consider how fervently you are objecting to my given definition of time and all the implications you think I'm making with it when it is indistinguishable from the definition you've given. :QuestionM

 

Assertion: "Ley lines are what specially designed dowsing rods measure."

This is a valid definition. If you created charts full of ley lines which were found by dousing then you could most properly define "ley lines" as "what the dowsing rod measured". This makes the least amount of assumptions about the nature of what the lines represent.

(Implication: If dowsing rods measure "it" then "it" must be real (as a real Earth Force of some kind.)

This would not be a logical implication. It's a fine analogy you're making. If someone said "time must be a real physical entity because clocks reliably measure it" then you could rightfully use this analogy and this objection. I haven't seen anyone in this thread say that or make that implicaion, but we're now fully prepared if somebody does ;)

Your curved magnetic field doesn't even approach the ontological debunking of 'time as established by clocks' presented above.

I don't know what this means. If you're trying to debunk my definition (which I stole from Einstein) then you're debunking your own definition as well. I'm fully open to defining space and time differently, but only if it is a useful or usable definition. As far as the ontology of time...

 

I personally do not believe distance or duration are ontological entities. I must admit that I do not understand their fundamental nature, so I could certainly be wrong. But, to me the time between events seems like a function of whatever matter or energy is interacting with the events. The distance between the earth and moon is not an ontological element in and of itself. Anything moving from one object to the other (including light) would include the property of distance, but the distance need not exist of its own accord.

 

~modest

 

As an aside, Michael, you might want to look up "inertia" and "momentum". In your second to last post to me you used the phrase "change in inertia" as a proposed cause of time dilation where I'm sure you're confusing inertia and momentum. I also noticed you're still saying "event duration". An event has the same meaning in philosophy and physics—it has no duration. I'm sure you'll take this constructive criticism like I'm trying to debate you... but :hihi:

[Boof-head]

Clocks measure reality (their reality)

How do clocks do that?

[Essay]

How do clocks do that?

By ticking? :QuestionM :hihi:

 

...but seriously:

Maybe I should have said clocks "reflect" reality.

 

Sure, clocks "measure" the advance of duration as we "tell them to" --as we construct them.

 

But if reality [the local, clock's reality] slows or otherwise changes, then the clock reflects that.

<this is referring to inside a spaceship, say--versus on the surface of Earth>

===

 

Atomic clocks run differently--relative to each other--because of differences in gravity or velocity, don't they? It is the atomic decay which is being affected, isn't it?

 

p.s. To be clear, that slowing of reality, for the clock, is only measurable relative to some other clock's reality. I'm not saying the clock "appears" to slow down to a present observer--but only relative to some distant "objective" reference.

[Boof-head]

Another thing about wanting to know what time it is: when you "look at the time" you're aware that whatever it says it's only accurate to within a certain limit. Most people deal with a few minutes of inaccurate time-keeping constantly and life goes on - it's important for GPS, the internet, scientific experiments - we like accuracy.

 

But any recording of any instant of time, is always "what the time was" when it was recorded; when you look at a clock on a wall, you're seeing what time it 'was' not what time it is. It was the time you heard the last tick, or whatever the signal from the device. Ipso facto, now does not exist. But then does.

[watcher]

i lend support to pyrotex's time.

time is the measure of change

one infinitesimal change correspond to one unit of infinitesimal time

every change is a change of one particle's position to another.

to understand time then we must understand how does particle moves or how does particle change position?

[Pyrotex]

No, they don't.

Clocks don't measure a thing; we just tell ourselves "clocks keep track of time", but this isn't really the case, we keep track of time, by looking at a clock, or listening to a talking clock, or seeing where the sun is or how dark or light the sky looks. We're the measurers, measurement isn't something inanimate matter is capable of.

I disagree.

Clocks count their incremental changes of internal state.

We have lots of machines, simple machines not computers, that can "count".

Turnstyles.

 

Clocks count time. They do not interpret what it "means".

Humans interpret the measure of time. We give it meaning.

[Boof-head]

Clocks count their incremental changes of internal state.

We have lots of machines, simple machines not computers, that can "count".

Strictly speaking, a machine doesn't 'do' anything, we say that it does, that a clock "keeps time"; this is a figure of speech, since obviously clocks don't keep anything. except they keep going (perhaps).

 

If you build a "time-keeping" device, you mean it will have a certain regular motion (a pendulum swinging, say) and you can construct a 'counter' to accumulate each regular transition, and leave the device calculating its time-integral.

 

But if you never "measure" the output, the device won't 'do' anything, since the purpose of the thing, is to collect time, and let you see the result - seeing the result is required, for the device to work as intended.

 

Clocks count time. They do not interpret what it "means".

There you go.

[Pyrotex]

Let's not go pulling the semantic rugs out from under each other's feet. ;)

When I say the 'clock counts time', I intend that in the same mechanical mindless sense that trees accumulate growth rings and the bottom of the Mississippi River accumulates silt.

The clock counts time.

The clock does not 'know' it's counting time. It knows nothing.

The clock has no 'intention' to count time.

The clock is not 'aware' of counting or of time.

The clock just counts time. That is what it was made to do.

It is a teleological object whose purpose of design is to count time.

Clock <== Count(Time)

 

As a gift to you -- here is an old-fashioned key-wound alarm clock.

I have painted the face black and removed all the hands.

It keeps perfect time.

You may find that you have certain sensory limitions in your ability to 'read' it.

:hihi:

[Michael Mooney]

Modest,

On how you reify time and I don't:

What do you mean by "time dilation?" What "dilates" if the term means more than a clock slowing down under whatever condition?

 

BTW: I use the phrase "event duration" like a "time exposure photo" of a natural event like the rotating or orbiting earth. Of course it just keeps spinning and orbiting, so the "event" is defined by the "photographer" who decides how to "set" the duration of open lens exposure. If his "event" is one earth rotation, a "day" he will set it for one complete revolution, etc.

 

(Yes, I also understand the common usage of "event" as anything manifest anywhere... and how relativity designates the relationship between such "events." My usage illustrates what "time" is.... that which "elapses" as things "happen", move etc. So that doesn't make time an entity that can "dilate." The latter is reification.

Michael

[Michael Mooney]

NomDePlume:

 

Michael- I believe (but if I put words in people's mouths, correct me) that the main argument people have raised with your ontology is that they believe one of the consequences of your ontology is that the speed of light will not be constant. IF this is true, you can see why its a problem, right?

 

Right. They misunderstand me. My beef is with "bent space" not with the bent path of light or its constant speed, which is very well established by SR. Light responds to mass/gravity *as if* it had mass. (We know that no mass can achieve lightspeed.) This is demonstrated in the "recoil" which Modest says that laser guns have and in the "box of mirrors" experiments in which captured light gives the box added inertia *as if* the photons bouncing off the walls had mass.

 

Further, there are two possibilities for our universe. We can extrapolate from our everyday intuition that "every effect has a cause," and extrapolate back infinitely far. Either the chain of effects eventually breaks and there is a "first cause," or there isn't and the universe is infinitely old, and always has been.

 

The problem with the latter is entropy. Now, I have only a vague conception of entropy, but I know that it always increases, which gives the universe a one way type character. This implies that something very special happened to give the universe a very low entropy sometime in the past. This pushes me toward first cause.

 

 

Seems to me that "first cause" is misconception of the limits of linear thinking. It always begs the question.... "So what before that?" Also, "something out of nothing" is exactly like belief in magic.

What was the supposed "first cause" that created cosmos out of "nothing yet existing?" It creates a logical absurdity, just like the religious creation myth.

 

But how do we know there is ever an absence of stuff? What if what we perceive as void is actually a material entity, Aristotle's quintessence or Aether. Your objection that "void" cannot have properties can be dealt with by saying that quintessence CAN have properties. It is my understanding that the Higgs field is this sort of quintessence or Aether that fills all space.

 

Hence, the universe may have "matter stuff" and "void stuff" but is nowhere empty.

 

What would you call the relative lack of 'stuff' we call "space" in both micro (within matter... see my "black-hole-earth' contrast) and macro... as in common usage... the space between objects on cosmic scale? Of course "stuff" exists between the major objects... dust here, a stray atom there... but where there is no such 'stuff' is emptiness... No? ... Oh yes, and the forces, electromagnetic and gravitational...

Is this what you mean that space is totally filled with stuff?

I don't define these forces as 'stuff', but maybe this is simply semantics. I say that these forces propagate through empty space.

 

I contrast the lack of manifest stuff/objects (space) with the "occupied space" wherever any manifest object exists.

 

Anyway... those who say that space curves, has shape, expands, contracts are making "space itself" into an entity with properties.

My ontology for this thread denies that reification.

 

Michael

[NomDePlume]

Michael, I think to be fair there are misunderstandings on both sides. I think that, very early on, someone (freezetar or modest maybe?) suggested that the specific feature of your ontology of simultaneous "now" in some way contradicts the speed of light (its buried with all the arguments about photons without time and triangles, etc).

 

I do not know if this is a true assertion BUT if it can be proven that a simultaneous now DOES contradict a constant speed of light, then we are forced to conclude that no ontology with a simultaneous "now" can be correct. Does that make sense? Could one of our resident math/physics types weigh in on this?

 

Seems to me that "first cause" is misconception of the limits of linear thinking. It always begs the question.... "So what before that?" Also, "something out of nothing" is exactly like belief in magic.

 

A first cause, would (by definition) have nothing before it. You cannot logically ask "what came before time."

 

We have two choices- either we have an eternal universe or a first cause "something out of nothing." BOTH choices contradict our everyday experience (where nothing is eternal, and yet nothing is uncaused), neither contradict logic. I suggest the entropy argument I made earlier is the resolution as to which we should prefer. Also, you should read Hume on cause and effect.

 

What would you call the relative lack of 'stuff' we call "space"

 

The point, I think, is that we don't KNOW its an actual lack of stuff. The medieval scholastics, following Aristotle, endowed it with properties. It is logically consistent to denote matter as "matter stuff" and the lack of matter as "void stuff" which has different properties to matter, but is just as material.

 

Scholastics actually believed that particles were just condensed space. So planets and the sun where just regions where "void stuff" was denser.

 

I contrast the lack of manifest stuff/objects (space) with the "occupied space" wherever any manifest object exists.

 

This isn't enough for your argument. You have stated explicitly that "space" cannot have properties- for that to be true space must literally be nothing. If space is the quintessence of the scholastics, then it can certainly have properties.

 

Edit: a friend has informed that pre-Einstein scientists viewed space as filled with a quintessence or aether. This aether was the "sea" through which Maxwell's electricity and magnetism flowed. The logic was that all waves need a sea, so light waves must propagate on the aether sea.

[maddog]

... So that doesn't make time an entity that can "dilate." The latter is reification.Michael

Michael,

 

Please elaborate how "time dilation" whether by SR or GR is a reification of "time". I may

be dense, I just do make this connection you do. :shrug:

 

maddog

[maddog]

Right. They misunderstand me. My beef is with "bent space" not with the bent path of light or its constant speed, which is very well established by SR. Light responds to mass/gravity *as if* it had mass. (We know that no mass can achieve lightspeed.) This is demonstrated in the "recoil" which Modest says that laser guns have and in the "box of mirrors" experiments in which captured light gives the box added inertia *as if* the photons bouncing off the walls had mass.

You forget that [imath]E = mc^2[/imath]. So a photon responds as though it "mass" is

really saying "because it has an energy density in its proximity". The photon "is" a packet

of energy quantized into a localized "space". That gives it it's particle like properties.

Anyway... those who say that space curves, has shape, expands, contracts are making "space itself" into an entity with properties.

My ontology for this thread denies that reification.

I guess this gets to the heart of it wrt Ontology:

 

What is it about Ontology that reifies a concept when that concept ascribes properties ?

 

If this were truly so, you would then reifying this "empty space of nothing" with the

ascribing of the property of being void of anything.... Seems to me... :shrug:

 

Of course you can elaborate a bit more thoroughly.

 

maddog

[maddog]

Michael, I think to be fair there are misunderstandings on both sides. I think that, very early on, someone (freezetar or modest maybe?) suggested that the specific feature of your ontology of simultaneous "now" in some way contradicts the speed of light (its buried with all the arguments about photons without time and triangles, etc).

 

I do not know if this is a true assertion BUT if it can be proven that a simultaneous now DOES contradict a constant speed of light, then we are forced to conclude that no ontology with a simultaneous "now" can be correct. Does that make sense? Could one of our resident math/physics types weigh in on this?

NomDePlume,

 

There was a "Now" the Michael was describing on this thread (earlier) (which he may still

beleive in) where the "now" expanding like an instantaneous wave out to infinity (or edge of

the universe if you prefer) from where you are standing. This notion is very classical

greek (Aristotle, Plato, etc) yet is in marked contrast from modern science. You can

not be aware of this "Now" everywhere at the same time. No signal (at least real)

can travel the distance in time. So this "awareness" would have to be "out of time".

The Gnostic tradition has instantaneous knowledge in this way. Were this to be expressed

in some physical way, then Tachyon particles would have to exist in some way. Though

they have Causality issues, some physicists are considering the possibility (fringe though

it may be).

 

On the other hand; you can in your mind comptemplate the concept of such a "now".

Even though in the concept [now] of instantaneous awareness, this is not the same

"now" as the present instant - "now".

 

Except for Michael I think you will have near universal disagreement with this now. As

somewhat of a heretic myself, I am considering in what ways that some form of

Tachyon type particles could coexist and not wreck QM, GR, and Causality. :shrug:

 

maddog

[Boof-head]

As a gift to you -- here is an old-fashioned key-wound alarm clock.

I have painted the face black and removed all the hands.

It keeps perfect time.

You may find that you have certain sensory limitions in your ability to 'read' it.

Did you set the alarm, and for what "time"?

 

Again with the ontology whatsit; you state: "it keeps perfect time". Therefore the following questions come to mind (epistemologically speaking), which are:

1) Where does it keep it?

2) Is perfect time the same as "ordinary" time?

3) Does the device make any noise, on a regular repetitive basis (does it tick)?

4) Can it be modified, so that an observer can also see, say, the innards 'moving around'?

 

Bearing in mind, that I believe the only form of "perfect time" is that which fundamental particles 'have', when they "go somewhere".

("I'm going outside for a while", said the electron to its nucleus, "I may be some time"... "Well, that's just perfect", said the nucleus)