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Since this has become another 'what is time?' thread, I would again like to raise the ontological question which the physics standard definition, "Time is that which clocks measure..." does not answer. By the same principle we could validate the existence of "the human aura" as "that which 'aura-meters' measure," but that is just another tautology which does not in fact validate the "human aura." I think that Justinw nailed it in on 28 October 2011 - 09:47 AM, (post 29): My bold! I think so. Time is the concept that motion (everything moves) 'takes time', not that it creates something called time or, as above "detects" time. The faster one thing moves relative to another thing, the more its rate of internal system dynamics slows down relative to the slower moving system. This echos, I think, what michel123456 said: ... except that there is no standard time speed, just faster and slower physical processes relative to each other, depending (for the relativity effect) on relative velocity of each system, gravitational field of each physical system, etc. To revisit 'another time, another thread, another thought experiment'... It takes Earth 'a year' to orbit the Sun. But if a rocket blasted off from Earth and went near lightspeed out for an Earth year and back for another Earth year, the rocket's clock/calendar might show that only one 'speeding rocket year' had elapsed, because its clock had slowed down with high velocity relative to Earth. The voyagers would have, I presume, only aged a year as well, while folks on Earth would have aged two Earth years. This is, I think, consistent with relativity without making "time itself" into "something" besides different relative rates of physical motion for Earth and its inhabitants vs a speeding rocket and its passengers.

Pantheory, Just a reminder... Please answer my post 12 above... "...it remains an honest and sincere question in my mind."

Please re-read my comments on presentism (and research the topic in general.) Presentism asserts that the present IS now happening everywhere simultaneously. Now, the ongoing present does not depend on frames of reference, as does relativity's assertion that reality depends on the frame of reference from which events are observed. In fact, presentism posits a universal now without a "frame" around it at all.

Sorry about my above criticism of Swansont. It won't happen again. I would like to distinguish between the concepts of time slowing down ("time dilation") and physical processes slowing down, whether the rate of clocks' "ticking" or the possible slowing down of the human aging process in high speed space travelers relative to those on Earth they left behind. Maybe it's just semantics, but if science claims that time dilation is different than clocks and physical processes slowing down then I would like to see that distinction made clear in the interest of the ontology of time, i.e., what it is that is supposed to be 'dilating.'

I am familiar with the aspect of relativity called the relativity of simultaneity. From Wikipedia: As an advocate of presentism, I dispute the above. Now IS now, both here and on the Sun, even though they are separated in space. All reality does NOT depend on " the observers framer of reference,"... so presentism also disputes the assertion (Wiki, continued): They are observed in different order even though they occursimultaneously. My comments were in reply to michel123456's 10/26 post: I said: My further comments were responding in agreement with michel that there is always a delay between events happening now and our present perception/experience of those events, whether right in front of our faces or at greater distances.

Pantheory: Why deny the motion of galaxies as observed, moving away from each other? Regarding Einstein’s proposal, it does not address the ontological question, “What is space?”, that it can be warped and expand. I've been told quite often here that such ontological questions as "what is it?" do not much concern physicists/cosmologists. Yet it remains an honest and sincere question in my mind. Is there no possible answer? The rest of your post could only make sense to me if the above were answered. Thanks for your efforts. Grammar edit.

Swansont's version of a debate: "No, actually, it's not at all like that." (You are wrong and I am right.) Your objections are "strawman" arguments. Period. No specifics as to how your argument is invalid. Just, 'strawman, strawman!' I know. I have been accused of the same. This may get me kicked out, as Swansont is packing "iron" to blow me out of here, quite the forum bully. I'd like to see scientific dialogue prevail here without the heavy handed "mainstream must not be questioned" tactics enforced by Swansont.

“As space expands,...” The* assumption* here is that space is something that expands. Ontology asks what space is as an expanding “something.” Objects in space move further apart as time elapses, but how does this translate into “space itself” (a supposed entity) expanding? A sincere question. An honest answer would be appreciated.

JustinW, I started a similar thread awhile back in the Astronomy and Cosmology section, "Before the Bang... where did it all come from." http://www.scienceforums.net/topic/55102-before-the-bang/page__p__591527__f I'd be interested in your take on that conservation.

None of your business. I value my privacy and a good bit of anonymity for good reasons of my own. That's why I didn't share any biographical info when I joined this forum. I always tell the truth (as I know it, of course), and I don't care a whit whether or not you believe me.

Myuncle: Me too... tired of the reification of time. Thanks. I understand time as event duration of physical processes. Clocks’ rates of "ticking” (physical process) slow down in various conditions. Time is not “something” that slows down (“dilates.”) I suspect that the rate of human aging also slows down at high velocities, so high speed space voyagers would probably age more slowly than their Earth bound counterparts. But this is NOT an argument for "time travel." (If the theory's referents don't exist in reality.) Again, kudos to you. So I have constantly maintained* in my ongoing debate with relativity theorists in this forum. *(Frequently citing Kelley Ross’ paper on “The Ontology and Cosmology of Non-Euclidean Geometry.”) Yup. And how about combining "time" with space (the volume in which all things exist) to "fabricate" the "fabric of spacetime," one of my favorite subjects to criticize. Again, thank you.

As I said: As a psychologist having studied the physiology of perception, I well know that, even with an event happening right in front of our faces, "it takes time" for a visual image of 'what IS happening' to reach the visual cortex and be "experienced" as "now happening." In that sense, I agree. Our experience of "now" always has a signal delay factor between the "now happening" event and our "now experiencing" that event. Same principle holds for longer distances between event and perception of event, but that does not deny that the universal present is now happening everywhere. My favorite example is that a flare on the Sun happening now will take 8+ minutes to be seen on Earth, but that does not deny that "the present" IS now, simultaneously happening both here and there. This, of course, contradicts relativity's claim that simultaneity is relative to the velocity, etc. of all different frames of reference... (that all "reality" depends on the frames of reference from which events are observed.)

The past is a record of everything that *has happened*. The present is now happening.

Can we not say that, until there is an explanation for how the force of gravity works, it is an example of "action at a distance?" Whether or not it is universal, all masses mutually attracting all masses ( with force directly with massiveness and inversely with the square of distance between masses) and at what speed of propagation (lightspeed, it appears) are questions secondary to the thread topic question.

If I may participate without being accused of thread hijacking... My agreement with Mystery111 is agreement with presentism. Only the present, "now" exists. "Exists" IS the present tense of the verb 'to exist.' The Sun will someday burn out, in the future, but that event has not happened yet, except in the mind of "block universe"* theorists. Neanderthal man has long since become extinct... does not still exist, except in the mind, as above. The cutting edge between future and past IS the present, and now IS always now, whether or not we think of the present as analogous to something "flowing." In presentism there are no local boundaries around "now" even though it 'takes time' for one location to "see what's happening now" in another location. Wikipedia, Philosophy of Time: *Paul Davies on eternalism and the "block universe" of relativity: ... http://serendip.brynmawr.edu/local/scisoc/time/chennotes.html The Philosophy of Time... ... This clearly reifies time into an existing entity/medium which "contains" past, present and future. 36grit: This seems to deny causation itself from one instant to the next for the "one" in question. Presumably some series of events, like joining NASA's astronaut program and flying to the moon, would be required to get you from the beach to the moon, even in the context of presentism, and it certainly could not happen in "an instant." Mystery111: "The thing that stops you..." is lack of a series of causal events, as above.

name='Schrödinger's hat' timestamp='1319203521' post='633064' (quote tags not matching.??) So in spite of your criticism of my repetition, you need me to repeat my point. OK, here it is again: My question to Cap 'n R: Cap ‘n R: "Shape of Earth" was my "keynote example" for criticizing length contraction. Earth does not change shape (much.) It is in fact nearly spherical. If its shape depended on observational frames of reference, as Cap' n insists, as above, then "a severely oblate spheroid" might be an equally valid description. The point of the thread is made clear. You: No. Multiple repetitons didn't help you understand what I have been saying all along. And you clearly didn't bother to study the Kelley Ross paper on how the notion of 4-D spacetime (and 4-D objects) developed. Regardless of the theoretical manifolds (including the 4-D concept) developed in non-euclidean geometry, actual objects in the real world, like planet Earth are, intrinsically, objectively three dimensional. (Three axes... count 'em... describe all volume, space and objects with volume.) As an object which exists independent of observational FOR earth stays nearly spherical regardless of the FOR from which it is observed... the point of this thread... and this contradicts relativity's claim about the equal validity of all FORs in describing earth. Except that the reality of earth's shape depends on the FOR from which it is measured/observed. Yes, quite repetitive! Compared to the above major point, made many times in my "first five pages summary post), most of the rest of your objections are, as you say "minutia," and I will not "quibble"* over them if you still don't get what I said, yet again above. *(Maybe just a little...) You never did understand my "imagine no intelligent life observing..." challenge. Everything, of course is moving. That said, the average distance between earth and sun does not change with observational FOR. Cosmos and all its parts exist and have properties and relationships (like distances between them) intrinsically, objectively, independently of any/all frames of reference from which they are observed. (Oopse, there I said it again!) If, for one moment you could set aside the quite ironic absolute belief that "everything is relative," depending on frames of reference, you might see that, as per "presentism" "the present IS now everywhere." I know that relativity denies this ( i.e., the "relativity of simultenaity," introducing distances between and velocities of different FORs, as a different "now" for each, but that does not make presentism wrong. In fact it attempts to re-define "IS," making the present dependent on location/velocity of FORs... "time cones" and all. I am saying (over and over) that the shape of an object, according to realism, does not depend on the frame from which it is observed, whether at rest with it or flying by at very high speed. Objects don't actually change shape "in other reference frames." (Theme of thread.) I'm glad that the Lorentz transformation formulae are useful in finding the true shape of objects, translated from whatever "distortion" due to extreme relativity effects, but all length contraction advocates in this thread have denied that those effects are "distortions." See again me 'n the Cap 'n above: Me:... "that there is no objective, as-it-is shape of earth?" Cap ‘n: "Not across all reference frames, no." Can I rest my case now?

IM Egdall; quote from another thread: I understand that spacetime curvature is a mathematics/physics/relativity phrase. My philosophical (specifically ontological) inquiry has always been about the nature of time, space, and “spacetime” in the ”real world,”, i.e., what IS it, if anything as an existing entity besides the way it is used conceptually in the 4-D coordinate system developed from non-euclidean geometry and cosmology. In other words what are time and space as used in your phrase “time and space are warped or changed.?” To take your example of “time warp” for instance: I understand that clocks run slower in higher gravitational fields (and at higher velocities.) I do not argue with these facts. I argue that time is simply event duration of physical processes, and that the physical process of clocks “ticking” slower in the above cases does not mean that “something” , time has slowed down or “dilated.” Ontology, after all, investigates what “time” IS. Same with space. Ontology asks “What is it?” that is said to be “stretched” (or contracted) in the language of relativity referring to “length contraction?” My longstanding criticism of the latter is based on the philosophy of realism which contends that the cosmos and all its parts have intrinsic, objective properties and distances between objects which do not depend on the frame of reference from which they are observed. (Cosmos would not change with no observers present.) Your example is a bit different, placing the Earth “under” two points (one above the other) in space. Ontology would require that your “points in space” be some kind of entities to “exist in the real world”, not just as conceptual/virtual loci, "points" in a coordinate system. So they could be space buoys placed at rest relative to each other. A long ruler could be placed between them. This distance will not fluctuate with frame of reference from which it is observed (according to realism), but “placing Earth” under them would introduce gravity and pull them (now objects with mass) both closer together and closer to earth. I can see no case in which the distance between them would be “stretched” by Earth’s presence.

I’d better answer you in my “Ontology of Spacetime” thread in the Philosophy section. I don’t mean to “hijack” this thread to promote my criticism of the use of “spacetime” in relativity.

Mystery111, Whatever the misunderstanding or disagreement which has arisen between us, I think you have summed up "the present time" very well in this from your post 11, with which I totally agree: Thanks.

Mystery111, You seem to not understand what I meant very well. I think you and I are in closer agreement than you think. You say: I agree that "there IS only the present." But It makes no sense (to me) to say, "It is not that the future is not yet present and the past is not still present." (my bold) The Einstein quote said that ..."...the distinction between past, present, and future is only a stubbornly persistent illusion." The distinction is that "future is not yet present and the past is not still present"... and in between them IS the ongoing present. He did not, of course, believe that time is an entity, and with that we both agree. He once said that if all matter disappeared, time and space would also disappear. Of course, moving matter requires "elapsed time", without making it an entity. (I dispute that space would disappear. It would just become empty space.) Huh? Everything in the cosmos IS in motion, with our without clocks. (Of course, in the general sense, everything moving IS a "clock.) How so? Or maybe this post clarifies what I meant.(?)

"Actually?" So it's settled then and those ISASS conferences and papers on spacetime were in vain... probably just a bunch of crackpots anyway. Cap 'n R admitted that spacetime is not ontologically real when he likened it to a "tie-died rabbit pelt", a non-entity, yes, just a "model" used conceptually in Minkowski's 4-D "spacetime", with no claim to existence as an entity. For the first time here I looked (in vain) for a place to report abuse. Note to Admin: This is a formal complaint against md65536 for the above inflammatory remarks (that which "trolls" do)... a venomous vilification, a very hostile personal insult and attack. My contributions here are sincere, with no malicious motives. Questioning and challenging mainstream science does not qualify as malicious.

IM Egdall: Ontologically the question remains, "What curves?" Giving some mystery medium a name and attributing malleability to "it" does not make it an existing entity or anything more than a concept upon which a non-Euclidean coordinate system is built. Neither does it explain how mass attracts mass "at a distance." There is a lot of controversy over the ontology of spacetime, including two volumes of it edited by Deiks from years of papers presented at conventions of the International Society for the Advanced Study of Spacetime . Aristarchus in Exile: "If"... If space is simply the volume in which all things exist, then what kind of entity is it supposed to be that it has become a malleable medium? If gravity has been constant among all masses through all time, then it simply becomes weaker with more distance between masses, as per the old "universal law of gravitation." From my last post in my "Spacetime Ontology" thread in the Philosophy section... very relevant here:

Mystery111: I was contrasting the Einstein quote: ....with your statement: ... My point was that the latter recognition (that the past and future do not still/yet presently exist) seems to contradict the direct (“People like us...”) quote above. Of course the future IS not yet present; and the past IS not still present. To your links... I agree with Barbour that time is simply duration. My definition, shared often in this forum: event duration of physical events. Markopoulou states that: Is volume “real?” A line is one dimensional. A plane is two dimensional. Volume is three dimensional, whether applied to space or objects in space. When stuff moves through space we say that “time elapses” but this does not mean that time is "something” other than the duration of such events of physical movement. If there were no clocks (or people) everything in the cosmos would still be in motion. We say that such movement "takes time," but we need not reify time, or "make something of it" because of the duration of events. Nor can "it" be "woven together with space" to create the "fabric of spacetime" as many of the critics in the ISASS contend.

Isn't gravity a universal case of non-locality or action at a distance since we don't know how the force of mass attracting mass works?

So, it's settled then, as my last statement (and my last posting showing the run-around I got on this topic) remains unchallenged.