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# What's Up With Gravity And Spacetime Curvature?

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Well, like I said, F=MA is can't be understood unless, at a minimum, you understand the concepts of force, mass, and acceleration.

As demonstrated in this forum, there seems to be a fair amount of confusion and uncertainty about all of these terms.  Same with the concept of inertia (which is basically what "mass" is).

And this is what I think it can be easy to overlook.  It is a simple matter to mechanically apply a math formula learned by rote.  All you need is some data input, and away you go.  You can be quite confident that you have arrived at the "correct" result in most cases. It's "easy."  But understanding the math is a completely different thing than understanding the content which you are manipulating with symbols when you perform your calculations.  The ease gives some a false confidence that they have to be  "right" and that their conclusions have been "proven."

As I said before, I could understand the math procedures which might lead one to assert that "time pointing downwards" causes gravity.  But even so, without more I could never understand the assertion being made.

I''m sure that's the point you were getting at, Popeye, when you said this:

Oh, I have seen many videos and I can derive the mathematical equivalency e=mc^2 in at least two different ways, and I have done so on this forum.

That still does not get at the fundamental property of mass and energy.

Edited by Moronium

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That still does not get at the fundamental property of mass and energy.

Energy, as I understanding it, is "the capacity to do work."  Mass is not matter (although it is a concomitant of matter).  Mass is, technically speaking, "resistance to acceleration," at least in Newtonian terms.

So, to say e = m is basically saying that "the capacity to do work is resistance to acceleration."  What does that even mean?

It might make some sense if you're talking about potential energy.  But what is that, really?  Potential energy is not energy, it is potential.  And energy itself is a "potential" (to do work).  So now we have a potential potential.  Sounds kinda nebulous, eh?

Edited by Moronium
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... this theory is a waste of my time. I don't possibly see any way all the contradictions of that definition could ever be explained away. I'm out.

So now you've decided to abandon SR altogether, eh, Ralf?  I can certainly understand that.  But if SR doesn't adequately explain things, what does, ya figure?

Edited by Moronium
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Why the theory of ralfativity of course. There is no crazy subjective definition of time where past, present and future are all concurrent and time does not flow. Relativity of simultaneity between perspectives is not as important as the causality between an event and its effects on those perspectives delayed by c. While the relativity of simultaneity and perspective can change the order of events, it can't change the order of causality. Physics doesn't create information that we can use to understand it, the information itself is physics and the programming language of the information is mathematics (not philosophy). That's why I like only one thing about relativity, the Rindler/Minkowski metric definition of the cause of age difference because the math doesn't care what you call the physical term for it. Unfortunately, the one thing relativity got right isn't part of my theory. My math explanation doesn't go beyond basic algebra. This should make it quite easy for any high schooler to falsify my theory.

Unfortunately I just tried to upload a sample of one of my graphs and there is a 190kb upload limit and most of my graphs are between 500kb and 999kb.

My IP is banned from this forum so I can't see what I linked to. Is it a huge graph that looks like a satellite dish from Arecibo?

Edited by ralfcis
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That's why I like only one thing about relativity, the Rindler/Minkowski metric definition of the cause of age difference because the math doesn't care what you call the physical term for it.

All the geometrical "metric" mumbo jumbo does nothing to explain the "cause" of age difference.  It merely spells out the constructs supposedly used to predict it.

2 + 2 = 4 may explain why you end up with \$4 if you add \$2 to an existing bank account which already has \$2 in it, but it doesn't "cause" 2 + 2 to equal 4.

Likewise the pythagorean theorem doesn't cause right triangles to have the particular trigonometric properties that they do.  It merely "codifies," in mathematical form, a pre-existing relationship.

Best we can tell, absolute motion causes time dilation, which in turn results in an age difference.  The "metric" does not cause it.

Edited by Moronium
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Why the theory of ralfativity of course. There is no crazy subjective definition of time where past, present and future are all concurrent and time does not flow.

My IP is banned from this forum so I can't see what I linked to. Is it a huge graph that looks like a satellite dish from Arecibo?

It can't be any worse than some of the other theories posted here.

I can see your graph OK.

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I can't post blind and I can't post graphs from my own files so I can't post my theory here. Even if I did, it would not be understood, Moronium doesn't read, he just posts so there would be constant distraction, and even if there were experts here that could put the theory through the ringer, no expert would waste his time doing that. It would make even less sense if I had to post in alternative theories, then there'd be no chance an expert could stumble across it. I need to get back on thescienceforum.com somehow. Can anyone tell the forum Nazi I promise to behave and not ruffle the feathers of his ignorant parrots anymore? That apology should do the trick.

Edited by ralfcis
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I just thought of a great example why time can't be likened to a spatial dimension (even if you call time ct). Let's assume the fourth spatial dimension is temperature instead of time. Each point in space has its own temperature just like it has its own time coordinate. But temperature doesn't have a fixed direction; you can turn down the thermostat but you can't go back in time. Temperature is a valid 4th space-like dimension. Temperature does not have to be continuously flowing at a rate of temperature. Time is always flowing at the normal rate of time in your own frame and it only stops flowing from someone else's perspective of you if you are going at c relative to him. Space only "flows" if you apply time to it, otherwise it is static and immutable (I have many reasons why the idea of length contraction is a mathematical construct that is not required to explain anything, even the constancy of c.) The number one reason length contraction is not real but an illusion of perspective is that there is a twin paradox for time but none for space (although it would a boon for the diet industry if the travelling twin could come back permanently thinner due to some permanent form of length contraction).

Edited by ralfcis
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OK, I've said it elsewhere, but I'll just come out with it again here.

I don't believe in "spacetime."  I'll concede that it can be very useful as a strictly fictitious mathematical tool, but I can't see where it has any correspondence to physical reality.

I made this post in another thread, but it's equally relevant here, too:

I'm no expert on GR, by any means, but I understand that the fundamental sourrce of the conflict between QM and GR is that QM, contrary to GR, presupposes a flat, Euclidean, space consisting of 3 + 1 dimensions.

For this reason, John S. Bell (of Bell's theorem notoriety), among others, has suggested that the simplest way to resolve the conflict is to revert to a Lorentzian conception of relative motion, which presumes absolute simultaneity and eschews SR's concept of "relative simultaneity."

As far as I know, there is no known phenomena which are purportedly "explained" by "spacetime" which cannot be adequately explained without invoking the notion of "spacetime."  The concept of spacetime is a postulated notion that can never be empirically verified

... I would say that the cheapest resolution is something like going back to relativity as it was before Einstein, when people like Lorentz and Poincare thought that there was an aether—a preferred frame of reference—but that our measuring instruments were distorted by motion in such a way that we could not detect motion through the aether. Now, in that way you can imagine that there is a preferred frame of reference, and in this preferred frame of reference things do go faster than light. ... Behind the apparent Lorentz invariance of the phenomena, there is a deeper level which is not Lorentz invariant... [This] pre-Einstein position of Lorentz and Poincare, Larmor and Fitzgerald (sic), was perfectly coherent, and is not inconsistent with relativity theory. (J. S. Bell)

https://pdfs.semanticscholar.org/160c/930e839a2f1ff0b378cb6372640f9c00d541.pdf

Edited by Moronium
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For this reason, John S. Bell (of Bell's theorem notoriety), among others, has suggested that the simplest way to resolve the conflict is to revert to a Lorentzian conception of relative motion, which presumes absolute simultaneity and eschews SR's concept of "relative simultaneity.

https://pdfs.semanticscholar.org/160c/930e839a2f1ff0b378cb6372640f9c00d541.pdf

How does your "math" resolve that issue, I wonder, eh, GAHD?  Does the math "explain it all?"

I imagine that modern day members of the Pythagorean cult, as you appear to be, have an answer to this, but, like I said, they wouldn't let my sorry *** join.

Chem most certainly has the answer, too, so I'm asking him the same question.

Edited by Moronium
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As Einstein himself clearly stated, the math does not formulate, or dictate, the theoretical hypothesis.  To the contrary, the (unverifiable) hypothesis dictates the math that needs to be employed.

The fundamental theoretical issues cannot be resolved by "learning the math," sorry, GAHD (and Chem).

Incidentally, as Einstein also pointed out, empirical observations do not, and cannot, dictate the theoretical hypothesis either.  That is the product of what Einstein called "the voluntary choice of a creative mind" (paraphrasing, at this point, because I haven't bothered to retrieve his words verbatim).

I took the time to look at Chem's profile.  Given that he lists "the philosophy of science" as one of his major interests, I'm kinda surprised that he never seems to have anything to contribute on that topic.

Edited by Moronium
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(although it would a boon for the diet industry if the travelling twin could come back permanently thinner due to some permanent form of length contraction).

I know I'd be standing sideways the whole trip!

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Henceforth space by itself, and time by itself, are doomed to fade away into mere shadows, and only a kind of union of the two will preserve an independent reality. (Hermann Minkowski, 1908)

So, time, "by itself," is a "mere shadow," eh?

Oooooh, how mystical.

Unfortunately, the esteemed Minkowski was a mathematician, not a physicist, and was not particularly qualified to ascertain much about an "independent reality."

Just as unfortunately, since his time, many so-called "physicists" have seemingly adopted the view that physics is math.  It aint.

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Speed is a ratio, i.e., distance traveled divided by time elapsed.  It is a concept which requires that you first ascertain both the amount of distance involved and the amount of corresponding time.

But, of course, once you postulate that a certain speed is always known, a priori, then you can simply mathematically deduce one of the other components.  They will be forced, by your postulate, to vary in accordance with your preordained determination of speed.  You no longer have to empirically establish time and distance.  This is the basis of Minkowski's conclusions about "independent reality."  If the facts don't fit the theory, well, then, so much the worse for the facts, as some theorist (Hegel) once said.

SR postulates that the speed of light is invariant (at least in a vacuum and in all inertial frames).  It is not invariant in an accelerating frame, as SR acknowledges.  But this is merely an unproven premise.  It seems odd that you can supposedly somehow "know" the speed, without ever knowing the (true) time and distance involved.  Interestingly, GR abandons the notion that the speed of light is invariant in all  inertial frames. In GR the gravitational time dilation is absolute, not relative.

As J.S. Bell, among many others, noted, there are perfectly coherent theories which postulate that the speed of light is not invariant in all inertial frames.  Such theories reject Minkowski's notion of "spacetime." This rejection allows QM to become compatible with gravity, which GR, with it's postulation of "curved spacetime," doesn't.

Edited by Moronium
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Einstein's clock synchronization procedure presupposes a  certain "one way" speed of light.  He himself said this was not a "fact" or a deduction, but merely an arbitrarily chosen dictum.

Physicists agree that there is no way to actually determine the one way speed of light, so any conclusion one makes about it cannot come from empirical observation.

SR posits that the average speed of light measured on a "round trip" can be "cut in half" to arrive at it's one-way speed in each direction, and is therefore the same, each way.

Other completely viable theories posit that the speed of light is not the same in each direction.  Such a theory (i.e. not SR) is used by the GPS

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Take 2 clocks, slowly separate them both very slowly. Use 1 to trigger a laser and the other to measure when it arrives. Subtract t1-t2 and you have the speed of light over the separation between them. That's a 1 way speed of light measured.

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Take 2 clocks, slowly separate them both very slowly. Use 1 to trigger a laser and the other to measure when it arrives. Subtract t1-t2 and you have the speed of light over the separation between them. That's a 1 way speed of light measured.

There are a number of physicists who have claimed to have measured a one way speed of light.  They have all been proven wrong.

The "one-way" speed of light, from a source to a detector, cannot be measured independently of a convention as to how to synchronize the clocks at the source and the detector. What can however be experimentally measured is the round-trip speed (or "two-way" speed of light) from the source to the detector and back again.

Experiments that attempted to directly probe the one-way speed of light independent of synchronization have been proposed, but none has succeeded in doing so.Those experiments directly establish that synchronization with slow clock-transport is equivalent to Einstein synchronization, which is an important feature of special relativity. Though those experiments don't directly establish the isotropy of the one-way speed of light, because it was shown that slow clock-transport, the laws of motion, and the way inertial reference frames are defined, already involve the assumption of isotropic one-way speeds and thus are conventional as well.

Many experiments intended to measure the one-way speed of light, or its variation with direction, have been (and occasionally still are) performed in which light follows a unidirectional path.[30] Claims have been made that those experiments have measured the one-way speed of light independently of any clock synchronisation convention, but they have all been shown to actually measure the two-way speed...

...This experiment, carried out in 1990 by the NASA Jet Propulsion Laboratory, measured the time of flight of light signals through a fibre optic link between two hydrogen maser clocks.[31] In 1992 the experimental results were analysed by Clifford Will who concluded that the experiment did actually measure the one-way speed of light.[11]   In 1997 the experiment was re-analysed by Zhang who showed that, in fact, only the two-way speed had been measured.

The first experimental determination of the speed of light was made by Ole Christensen Rømer. It may seem that this experiment measures the time for light to traverse part of the Earth's orbit and thus determines its one-way speed, however, this experiment was carefully re-analysed by Zhang, who showed that the measurement does not measure the speed independently of a clock synchronization scheme but actually used the Jupiter system as a slowly-transported clock to measure the light transit times.[33]

The Australian physicist Karlov also showed that Rømer actually measured the speed of light by implicitly making the assumption of the equality of the speeds of light back and forth.

https://en.wikipedia.org/wiki/One-way_speed_of_light#Experiments_which_appear_to_measure_the_one-way_speed_of_light

Try as hard as you like, but you'll never convince anybody that you have "proved" a conclusion by assuming it as a premise.  Such attempts are made daily in this forum, but, still...

Edited by Moronium

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