# Gravity Works Like This

You can say space is real by holding up your hands and indicating the very real gap between them. You can do the same for motion by waggling your hands.

How does "waggling your hands" show motion?

This is actually a great question, and one that Farsight has studiously avoided answering for years.

LOL, I just took a peek, and PhysBang's post is inane: How does "waggling your hands" show motion? Because then you can see it. Duh! Because motion is empirical.

And the idea that I've been studiously avoiding answering that for years is comical. I've been saying for years that you can see your hands moving, but you can't see time flowing.

So for PhysBang, it's back on ignore. It's back to...

This message is hidden because PhysBang is on your ignore list.

James, where are you?

Farsight

This message is hidden because PhysBang is on your ignore list.

Protecting you delicate skin from harsh old PhysBang's unwanted truths does not make you look smarter, you know. You lose when you run away from the criticizm and scorn you so richly deserve. Please put me on ignore as well, then we can talk smack about you uninterrupted by your whining and lying.

Grumpy

I remember years ago, Farsight, said his book was worthy at least five Noble prizes.

Farsight

The speed of light is constant in SR, but not in GR. If it was, a light beam wouldn't curve and your pencil wouldn't fall down. The local frame of reference relates to the principle of equivalence and a region of infinitesimal extent. A region of no extent. Look up coordinate speed of light, which varies in a "non-inertial reference frame". A gravitational field is a non-inertial reference frame.

The speed of light is constant in Relativity, all of it. Your statement is a lie. "Look up coordinate speed of light, which varies in a "non-inertial reference frame". Unfortunately for you the coordinate speed is not the actual speed of light through spacetime, which does not vary. Is this whole thing just your inability to understand the difference between coordinate speed and lightspeed through a vacuum c? They are not the same thing, you know.

Coordinate speed is the coordinate distance measured by the observer divided by the coordinate time of the observer. For example, at the event horizon of a black hole the coordinate speed of light is zero, while the proper speed is c. The coordinate speed of light (both instantaneous and average) is slowed in the presence of gravitational fields. The local instantaneous proper speed of light is always c.

http://en.wikipedia.org/wiki/Propagation_of_light_in_non-inertial_reference_frames

Even the Wiki definition of coordinate speed could straighten you out on your error, but it probably won't because you are a believer, immune to information that cannot be accommodated by what you believe.

This forum is for scientists, believers should stick to the religious forum and cranks belong in the cess pool.

Grumpy

HI Grumpy.

How can you be so 'certain' of anything you think you 'know' about it while you still haven't indicated any knowledge/understanding of the subtle but important difference/usage/meanings etc distinctions I already explained to you needed to be made between 'constant c' and invariant c' before you pretend to understand the QUESTION, let alone the answer?

Undefined, whether you believe that the speed of light is variable or not, \$\$c\$\$ is a constant, used in everything from SR and GR to quantum mechanics and cosmology. Maybe you should introduce a new term \$\$c_{varriable}\$\$ and provide some reasonable experimental support for using it in any theoretical model describing reality.

... A task I find unlikely, since the constancy of \$\$c\$\$ is based on real measurements.., and I see no realistic way to measure a variable speed of light.

That leaves any variable speed of light, at present.., restricted to a completely hypothetical or purely theoretical context. So how is it that you jump to any certainty that the speed of light is variable?

Just a reminder, outside our locally defined experience I have only theoretical opinions regarding the speed of light.

Even so, the mathematicians took over and took his theory into places/interpretations dead ends when the reality is consulted directly....as in the TWINS SCENARIO case; where NOW the mainstream explanations HAVE to INCLUDE the ACCELERATIONS profile information to make real sense of the disparity in aging of the twins above and beyond the RECIPROCAL POV of straight maths SR.

My first guess is, you have taken a detour, or have read some bad text.

The 'twin paradox' results from the erroneous assumption that mutual observations of the other clock determines the aging rate, when it does not. Since clocks are frequencies, they will appear to run slower or faster, i.e. doppler effects. The clock frequencies remain constant. It's each observers perception of the frequency that changes as a result of their relative motion.

1. The accumulated time can only be determined by a comparison of the clocks at a common location, and depends on the speed profile of each, from separation to rejoining.

In the typical scenario, A receives an image of the B clock, but a comparison of an earlier B-time to his current A-time doesn't allow for a determination of an aging rate. The typical response then is an allowance for light propagation time, especially if A is receiving a signal that originated at A. This is where we recall what the author of SR stated in his 1905 paper in par. 1. "We have so far defined only an ``A time'' and a ``B time.'' We have not defined a common ``time'' for A and B, for the latter cannot be defined at all unless we establish by definition ...". He then defines the outbound and inbound light paths to be equal. This results in an uncertainty of the coordinates of the remote event as calculated by A, with emphasis on 'by definition' and 'calculated'. Rigor can only take you so far, after that it's faith, in the form of postulates and axioms.
There are also the Minkowski diagrams for event counting between A and B, to decide any aging difference. Notice that to complete the count, they are coincident.

non-inertial motion
1. SR contains one new math expression, gamma, which contains a constant (1), and a variable (v/c), the ratio of object speed to light speed. Neither time dilation nor length contraction, which are calculated using gamma, depend on acceleration.
2. Muons subjected to high g accelerations, have a half life equal to muons in inertial motion.

Here is an example which eliminates the non-inertial motion.

View attachment 7006

How does "waggling your hands" show motion?

This is actually a great question, and one that Farsight has studiously avoided answering for years.

Can you explain your reasoning as to why that is a great question?

To be clear, I’ll define space as separation between two or more points, and motion as a change of position in space.

Meaning if something like you hand changes from one point to another point that is not as the same location (it is separated by space), that “waggling of hands” demonstrates motion. You may have just wanted to see Farsight’s answer and if that is the case ignore this paragraph. I would still like to understand why you think it was a great question?

It just goes slower. Read the OP. Light clocks don't go slower because your plot of light-clock rates is curved. And they don't go slower because distances increase, otherwise distances would have to be infinite at the black hole event horizon.
.

Since you have me on ignore along with many others who happen to disagree with your nonsense, you will not be able to see how your silly anti mainstream ideas will keep compounding upon each other...manufacture one alternative bit of rubbish, and you need to manufacture more and more...It's like a house of cards...Remove one, and it all comes tumbling down

Most of your answers are wrong, misleading or just theoretical unevidenced concepts,,,the above one is one that is easily explained.
The closer one gets to the EH of a BH, the more curved/warped space/time becomes.....The BH space/time curvature can lead to infinite space/time curvature and infinite densities.[A QGT may well eliminate those infinites]
So you see the photon at or near the EH, can have an extremely long path to travel due to this near infinite space/time curvature.
The photon itself will always remain at "c".
The other noteworthy point, which was discredited in another of your anti mainstream threads, is of course that photons are never seen at the EH from an outside FoR...the time dilation affect sees them red shifted to infinity while never quite reaching the EH.
From the photon's own FoR, it crosses the EH as if nothing has ever happened.

Going by the number of replies in rebuttal of the stance by you and undefined, I'm happy now to see this as decided in the mainstream favor.
I see the thread as closed and decided.
Thank you linesmen, thank you ballboys.

Maxila

I think it was in reference to coordinates. In order to define the waving of a hand the coordinates of the hand in motion must be used to describe that motion, thus to deny that coordinate systems are necessary in physics is seen as the idiocy it is. Not only that but the time element must always be specified as well. If I try to intercept the Earth returning from a space mission I must not only know where the Earth will be in the 3 dimensions of space, but I also need to know at what point in time it will be there, thus a 4D spacetime. This is true of all events, their location can not be described without knowing the position in space coordinates, but also one of time. A frame of reference contains these same elements, that's why we talk about frames, which is also something the know-nothings deny or denigrate as constructs. Of course they are constructs, but just like a blueprint corresponds with the structure being built, Relativity corresponds to reality.

Grumpy

Farsight

Protecting you delicate skin from harsh old PhysBang's unwanted truths does not make you look smarter, you know. You lose when you run away from the criticizm and scorn you so richly deserve. Please put me on ignore as well, then we can talk smack about you uninterrupted by your whining and lying.

Grumpy

Ditto.

Can you explain your reasoning as to why that is a great question?

To be clear, I’ll define space as separation between two or more points, and motion as a change of position in space.

Meaning if something like you hand changes from one point to another point that is not as the same location (it is separated by space), that “waggling of hands” demonstrates motion. You may have just wanted to see Farsight’s answer and if that is the case ignore this paragraph. I would still like to understand why you think it was a great question?
It is great because of something that you (somewhat) left out of your definition of motion: time. You implicitly referenced the change in position from one time to another in your definition.

Farsight believes that there is no time, only motion. Yet he has not shown us how we can "see" motion without time.

James R, where are you? Your moderator in this section is FAILING your trust and the site. Paddoboy has been reported for trolling and baiting and 'me too' mindless links and quotes and beliefs etc science-empty 'cluttering noise' posts intentionally burying threads/discussions in his troll crap obvious to all except BIASED MODERATOR(s) who is obviously using paddoboy troll as a 'stalking horse' make others riled enough so that the mod can then use the trumped up excuse to ban the VICTIM and leave the TROLL get on with the patently obvious troll agenda which is being tacitly 'approved/protected' by the MODERATOR(s) in this section. This MOD-TROLL tactic was PROVEN BEFORE and is NOT ACCEPTABLE in any really high quality site ANYMORE. Paddo is even worse that Tach was, at least Tach had SOME knowledge at all, not like this patent mindless stooge of a troll paddo. Yes?

Here is a perfect example of what paddoboy has been all about since he arrived at sciforums...

Please see exchange in post #458 and #459....

it shows clearly paddoboy wasting everyone's time and especially the OP's, where the OP presents scientifically objective empirically supported aguements and paddo just responds with his 'beliefs' and 'handles' as a layman who understands NE 'side' of discussion, either orthodoxy OR alternative understandings. That is OBVIOUS and should attract the moderator(s) attention by now. Paddo has been reported before and will be reported again, as per 'due process' advised, but NOTHING is done about his trolling, personalizing, disruption etc.

Please James, take control and get the mods to do the right thing at least ONCE before they have to be SHAMED into doing it. Nothing else seemed to work. No-one has taken a blind bit of notice 'in the system of reporting trolls' process, so this is a last ditch OPEN FORUM appeal to you in the threads where it's all happening under the mods noses. Please. Thanks.

How does "waggling your hands" show motion?

This is actually a great question, and one that Farsight has studiously avoided answering for years.

The same way you know "which way is up" in the room you are sitting in right now.

And if you really want to know how one can show one's hands are moving, you may easily tell they ARE moving if you happen to be standing too close to them and one of the hands 'waggles' too vigorously and hits you on the nose!

Unless of course it was YOU moving your nose and crashing into the 'waggling hand' on PURPOSE as in a comedy sketch about motion?

"Caution: Waggling hands moving! Please keep safe distance!"

That's your 'safety tip for the day', mate!

Farsight

The speed of light is constant in Relativity, all of it. Your statement is a lie. "Look up coordinate speed of light, which varies in a "non-inertial reference frame". Unfortunately for you the coordinate speed is not the actual speed of light through spacetime, which does not vary. Is this whole thing just your inability to understand the difference between coordinate speed and lightspeed through a vacuum c]? They are not the same thing, you know.

Coordinate speed is the coordinate distance measured by the observer divided by the coordinate time of the observer. For example, at the event horizon of a black hole the coordinate speed of light is zero, while the proper speed is c. The coordinate speed of light (both instantaneous and average) is slowed in the presence of gravitational fields. The local instantaneous proper speed of light is always c.

http://en.wikipedia.org/wiki/Propagation_of_light_in_non-inertial_reference_frames

Even the Wiki definition of coordinate speed could straighten you out on your error, but it probably won't because you are a believer, immune to information that cannot be accommodated by what you believe.

This forum is for scientists, believers should stick to the religious forum and cranks belong in the cess pool.

Grumpy

My red highlighting above.

Grumpy, mate, how can you sit there and admonish Farsight about "not knowing the difference" about anything, when you still haven't acknowledged the Difference between 'constant c' and 'invariant' as to usage/derivation/meaning and actual relation REAL LOCAL (NOT REMOTE CO-ORDINATE SR VIEWS) to Relativity's PREDICTED EFFECTS on CLOCKS/PROCESSES as Einstein explained in the GR 'rider' to the 2nd Postulate of SR? Remember also about the 'time' aspect/meaning/derivation by US the observers of events, as Penrose, Einstein already have clearly explained themselves?

Until you get off that kneejerking 'high horse' you have been busily riding while missing the point of what has already been explained to you, Russ, PhysBang et al, please stop making out as if you are in any position to admonish Farsight or Maxila or anyone else with whom your 'high horse beliefs' do not agree. OK?

It would be much appreciated, Grumpy. Cheers.

RC

James R, where are you? Your moderator in this section is FAILING your trust and the site. Paddoboy has been reported for trolling and baiting and 'me too' mindless links and quotes and beliefs etc science-empty 'cluttering noise' posts intentionally burying threads/discussions in his troll crap obvious to all except BIASED MODERATOR(s) who is obviously using paddoboy troll as a 'stalking horse' make others riled enough so that the mod can then use the trumped up excuse to ban the VICTIM and leave the TROLL get on with the patently obvious troll agenda which is being tacitly 'approved/protected' by the MODERATOR(s) in this section. This MOD-TROLL tactic was PROVEN BEFORE and is NOT ACCEPTABLE in any really high quality site ANYMORE. Paddo is even worse that Tach was, at least Tach had SOME knowledge at all, not like this patent mindless stooge of a troll paddo. Yes?

Cease your insipid whining and either address the egregious errors in your idiotic statements and lies or go away. paddoboy is not the delusional party here, you are. You and Farsight are on the edge of getting invited to carry your idiotic garbage elsewhere for your behavior, paddoboy is not. Do what you both usually do, run and hide and come back when you think no one is paying attention. Alternately, you can voluntarily withdraw to the cesspool and say anything you like, Spinozas got his own thread there and knows better than to interrupt serious discussions with his drivel. You will learn that lesson soon, I'm thinking.

Please James, take control and get the mods to do the right thing at least ONCE before they have to be SHAMED into doing it. Nothing else seemed to work. No-one has taken a blind bit of notice 'in the system of reporting trolls' process, so this is a last ditch OPEN FORUM appeal to you in the threads where it's all happening under the mods noses. Please. Thanks.

Again, be VERY careful what you ask for, you just might get it.

Grumpy

Hi OnlyMe.

Undefined, whether you believe that the speed of light is variable or not, \$\$c\$\$ is a constant, used in everything from SR and GR to quantum mechanics and cosmology. Maybe you should introduce a new term \$\$c_{varriable}\$\$ and provide some reasonable experimental support for using it in any theoretical model describing reality.

... A task I find unlikely, since the constancy of \$\$c\$\$ is based on real measurements.., and I see no realistic way to measure a variable speed of light.

That leaves any variable speed of light, at present.., restricted to a completely hypothetical or purely theoretical context. So how is it that you jump to any certainty that the speed of light is variable?

Just a reminder, outside our locally defined experience I have only theoretical opinions regarding the speed of light.

The maths ABSTRACTIONS and calculations which are used are useful, sure, but so were the EPICYCLES, remember? The point at this stage is to actually identify the REALITY POV, not the arbitrary abstract mathematical POV and interpretations, however useful they have been to date.

When currently it is interpreted that the 'spacetime' length contracts, it is a convenient reciproxal view ONLY. Becaue it is the 'time' part of that abstract math construct that is actually affected by SR-motion/GR-acceleration in-frame LOCAL (not abstract unreal co-ordinate view) REAL FORCES/PROCESSES.

So instead of just going along still with that 'spacetime' contraction which implies incorrectly that the 'space' component is 'contracting', why not just go for the obvious reality as per SR-motion/GR-acceleration effects predicted to affect the CLOCK 'time' component of that 'spacetime' construct....and just admit that the abstract 'spacetime' contraction is actually the REAL 'time' rate contraction OF the tick rate of the clock used in the in-frame 'measurement when calculating the ACTUAL light speed IN that frame based on the IN-frame CLOCK 'time' variation to the 'standard second' which WOULD HAVE applied IF the NEW in-frame SR-motional/GR-accelerational conditions had been the same as the standard second definition frame from which the standard was taken.

Hence whence the 'invariant c' is derived with the proportional offset of the 'clock time' and the lightsped, and NOT any 'space' length contraction needed at all. OnlyMe, everyone, please do NOT conflate/confuse this REAL 'invariant c' proportionate resultant quantity for the in-frame measure speed of light in every frame, due to compensating 'time' values used therein, with the purely mathematical equations TERM of 'constant c'. They are two different things!

Cheers, OnlyMe, at least I know you actually READ and try to understand properly, unlike some trolls and kneejerkers I could mention. Kudos to you, mate!

RC

Cease your insipid whining and either address the egregious errors in your idiotic statements and lies or go away. paddoboy is not the delusional party here, you are. You and Farsight are on the edge of getting invited to carry your idiotic garbage elsewhere for your behavior, paddoboy is not. Do what you both usually do, run and hide and come back when you think no one is paying attention. Alternately, you can voluntarily withdraw to the cesspool and say anything you like, Spinozas got his own thread there and knows better than to interrupt serious discussions with his drivel. You will learn that lesson soon, I'm thinking.

Again, be VERY careful what you ask for, you just might get it.

Grumpy

You don't read and understand the difference as explained between 'constant c' and 'invariant c'; you don't understand that empirically 'time' is the abstraction by us of a convenient observable/comparative MOTION/change in REAL events/process, as stated clearly by Penrose and Einstein; you ignore that in his 2nd Postulate Einstein himself cautioned via GR 'rider' that the validity of SR 'constancy of light speed' dos NOT extend to GR contexts LOCALLY not just 'reciprocal remote/co-ordinate views' whose SR limits of validity Einstein expressly covers in his GR 'rider'; you keep making personal insults and refuse to acknowledge the actual facts presented and just kneejerk from your long-obsolescent 'abstract math remote/co-ordinate' views when faced with the reality GR view LOCALLY....and all you can do is make more unsupported insults and claims in direct contradiction of the facts presented to you which make your stance untenable in reality view?

OK, mate, you're welcome to that ay of 'doing/understanding' science and science discourse, because it has strayed so far from the proper SCIENTIFIC METHOD into the 'RELIGIOUS BELIEFS METHOD' which both you and I have decried in the religious types. Maybe you have been playing too long with the religious beliefs types in the religious discussions section, and have contracted some of their MO?

If you can't even be bothered to counter cogently and less insulting/emotionally based on the actual facts presented, then what are you even doing here in the physics/maths section, mate? It's no good for your blood pressure or your back, Grumpy, to try to hold on to 'beliefs' in the face of new facts/perpsectives which are based on reality not abstractions. So let's call it quits on these matters/topics from which you only argue the maths view, mate, else you'll remain the same way that Einstein predicted:
Ever since the mathematicians have invaded my theory, I don't understand it myself anymore!----Einstein
!

No hard feelings mate, life's too short and complicated enough as it is, hey? Take care, Grumpy. Cheers.

Hi OnlyMe.

The maths ABSTRACTIONS and calculations which are used are useful, sure, but so were the EPICYCLES, remember? The point at this stage is to actually identify the REALITY POV, not the arbitrary abstract mathematical POV and interpretations, however useful they have been to date.

When currently it is interpreted that the 'spacetime' length contracts, it is a convenient reciproxal view ONLY. Becaue it is the 'time' part of that abstract math construct that is actually affected by SR-motion/GR-acceleration in-frame LOCAL (not abstract unreal co-ordinate view) REAL FORCES/PROCESSES.

So instead of just going along still with that 'spacetime' contraction which implies incorrectly that the 'space' component is 'contracting', why not just go for the obvious reality as per SR-motion/GR-acceleration effects predicted to affect the CLOCK 'time' component of that 'spacetime' construct....and just admit that the abstract 'spacetime' contraction is actually the REAL 'time' rate contraction OF the tick rate of the clock used in the in-frame 'measurement when calculating the ACTUAL light speed IN that frame based on the IN-frame CLOCK 'time' variation to the 'standard second' which WOULD HAVE applied IF the NEW in-frame SR-motional/GR-accelerational conditions had been the same as the standard second definition frame from which the standard was taken.

Hence whence the 'invariant c' is derived with the proportional offset of the 'clock time' and the lightsped, and NOT any 'space' length contraction needed at all. OnlyMe, everyone, please do NOT conflate/confuse this REAL 'invariant c' proportionate resultant quantity for the in-frame measure speed of light in every frame, due to compensating 'time' values used therein, with the purely mathematical equations TERM of 'constant c'. They are two different things!

Cheers, OnlyMe, at least I know you actually READ and try to understand properly, unlike some trolls and kneejerkers I could mention. Kudos to you, mate!

Most of what you believe to be real, is not that which can be known with any certainty. All we can know with certainty is that which we can experience and measure directly.

You keep telling almost everyone that they don't read or understand what you (and Farsight) are saying, but you don't seem to be even attempting to understand what I have been saying. There is a difference between knowing something because it has been objectively proven and the kind of knowing associated with believing something. There is a difference between what we know to be and what we believe to be.., between fact and theory... Between reality, fiction and fantasy!

You talk about this stuff as if it is something that can be or has been experienced, measured or experimentally proven directly. While almost all of it lies beyond any direct experience. In the end from what I have seen, it is a matter of interpretation and belief not reality based on objective experiment or experience, and even in that it runs counter to what is the general consensus today.

Most of what you believe to be real, is not that which can be known with any certainty. All we can know with certainty is that which we can experience and measure directly.

You keep telling almost everyone that they don't read or understand what you (and Farsight) are saying, but you don't seem to be even attempting to understand what I have been saying. There is a difference between knowing something because it has been objectively proven and the kind of knowing associated with believing something. There is a difference between what we know to be and what we believe to be.., between fact and theory... Between reality, fiction and fantasy!

You talk about this stuff as if it is something that can be or has been experienced, measured or experimentally proven directly. While almost all of it lies beyond any direct experience. In the end from what I have seen, it is a matter of interpretation and belief not reality based on objective experiment or experience, and even in that it runs counter to what is the general consensus today.

What's your game, mate? You're taking your 'sitting on the fence' angle to (painful?) absurd wishy-washy lengths.

Have you been watching/reading all these discussions properly?....

GR effects on clocks is PROVEN empirically EXACTLY as predicted by Einstein.

They can BE consulted DIRECTLY via the clock counter cumulative counts and COMPARED....LOCALLY and EMPIRICALLY for REAL not 'abstract'.

And Einstein already said in his GR 'rider' to the 2nd Postulate that the validity of the SR-only 'constancy of speed of light' view is NOT VALID in GR contexts.

Everything that Farsight and I have pointed out is empirically supported, as compared to the purely SR and 'abstract/remote co-ordinate overlays that are MADE MOOT by the LOCAL GR REALITY EFFECTS as Einstein predicted and are observed DIRECTLY in clocks in GR contexts.

Do you at least understand the crucial and subtle difference between the usages/meaning for the entirely different 'constant c' and 'invariant c; s I have explained more than once now to Grumpy et al (especially as it affects the current incorrect INTERPRETATION that 'length' instead of 'time' has changed)? If you have, then just RE-think everything through for yourself from there.

So what are you complaining about? There IS the LOCALLY REAL as predicted EFFECTS on CLOCKS/timing 'second' interval/tick to consult directly and confirm GR Relativity as Einstein predicted. What MORE do you want than that, OnlyMe?