A Question for Curved Spacetime.

[Phi for All]

37 minutes ago, J.Merrill said:

Yes  recognize it as a mistake, and I can admit that, how ever it is true that every theory has its flaws and this was my point I was trying to make. 

This isn't true either. It's not a flaw if a theory is used outside it's area of applicability. If you want to understand gravity better, you don't use Special Relativity, but that's not a flaw with SR.

[J.Merrill]

3 hours ago, Phi for All said:

This isn't true either. It's not a flaw if a theory is used outside it's area of applicability. If you want to understand gravity better, you don't use Special Relativity, but that's not a flaw with SR.

its not true that theories have flaws? 

 

All theories have flaws because they are developed by man. Due to this fact, all theories are constantly reevaluated whenever new information is discovered.

Edited June 20, 2022 by J.Merrill

[Phi for All]

21 minutes ago, J.Merrill said:

its not true that theories have flaws? 

 

All theories have flaws because they are developed by man. Due to this fact, all theories are constantly reevaluated whenever new information is discovered.

NO. Within the applicability of a theory, it has tremendous explanatory and predictive powers. Outside that, not so much, but that's not a mistake or flaw, it's a limitation. Is it a flaw that your house can't protect your car from the rain if you don't have a garage as well? 

Flawed because it was developed by man?! That sounds like religious guilt. Science itself was developed by man, and has been filling the gaps in our knowledge caused by belief in religions. Again, you see flaws where there's only limitations.

Now your last sentence is partially right. Theories aren't claimed as proof because they're constantly updated with the latest information from observation and experimentation. That's actually what makes theory the strongest concept in science. But again, it's not a flaw but rather the limitation of using the best CURRENT information. 

I can't think of a better way to make certain our knowledge is sound. We're always looking for better information rather than answers, because when you think you've found the answer, you stop looking. We don't ever want to stop looking.

[J.Merrill]

3 hours ago, Phi for All said:

 

Flawed because it was developed by man

Yes and this is not any thing to do with religion you can leave that comment out please. 

Humans are not perfect, like theories are limited , so are humans understanding of things, there are no answers for Some things we observe. Like the reason why Photons behave more like partials rather then waves when being observed.

Or what was before the big bang.

Where did it come from.

These are just questions that are shoved aside and not even considered. And in my personal belief if we cant explain these things then our understanding of what we believe to be true is certainly limited more than what we want to admit.

If I wrote 2 + 2 = 4 

The equation is true, I can apply this equation in physical form too, Two Fish + Two Fish = Four Fish. 

But if I said it was 5 wouldn't that be a flaw?

So if we apply the same concept to theories and our results give us " 2 + 2 = 5 " then its not limitation its a flaw. 

 

But I do agree with a lot of what you said, you made a good point.

 

[Phi for All]

50 minutes ago, J.Merrill said:

Yes and this is not any thing to do with religion you can leave that comment out please. 

OK. So it's more to do with our being fallible in the first place. But science tries to account for this.

52 minutes ago, J.Merrill said:

Humans are not perfect, like theories are limited , so are humans understanding of things, there are no answers for Some things we observe. 

Fine, but that still doesn't mean science or theories are "flawed" just because we're not perfect. This is an important distinction, between being wrong/flawed and being limited by our explanatory powers. And remember to make the distinction between answers and the best supported explanations. Science isn't looking for answers.

 

1 hour ago, J.Merrill said:

Or what was before the big bang.

Where did it come from.

These are just questions that are shoved aside and not even considered. And in my personal belief if we cant explain these things then our understanding of what we believe to be true is certainly limited more than what we want to admit.

Nobody is shoving aside these questions. Again, you misunderstand the reasoning behind the reasons. We CAN'T know for sure about anything that happened prior to the sudden expansion of the universe. Our ability to measure such things ends a tiny bit after the expansion began, so we can't know what was going on at t=0, much less before that. It would just be guesswork, since the necessary information is destroyed in the formation of our universe.

I don't understand your position on this at all. Are you saying that because we don't know what happened before the BB, we don't know anything?! 

[J.Merrill]

3 hours ago, Phi for All said:

I don't understand your position on this at all. Are you saying that because we don't know what happened before the BB, we don't know anything?! 

LOL I never said this, it seems people don't read things as they are wrote but instead try to assume what one meant. 

You have even proved my point, we are limited to things we know. And always will be, but how can we accurately compare any model to anything if we don't have a full unlimited knowledge of how it all started and why.

Cause and Effect is a thing.

 

And what do you mean science isn't looking for answers? I cant disagree more if you ask a question then you want a what?

And science questions things that as you stated, religion doesn't explain. 

Science is always questioning and the questions derive from Uncertainty or Problems. There will never be a SOLID theory with Fool proof answers. There is always a meaning full question out side of just why.

Curiosity is what motivated Einstein, he was passionately curious. He questioned everything that he found answers too and made mistakes along the way.

 

 

Edited June 20, 2022 by J.Merrill

[Phi for All]

2 minutes ago, J.Merrill said:

And what do you mean science isn't looking for answers? I cant disagree more if you ask a question then you want a what?

Well, I'll repeat myself, but now you don't get to whine about others not reading what you wrote

1 hour ago, Phi for All said:

I can't think of a better way to make certain our knowledge is sound. We're always looking for better information rather than answers, because when you think you've found the answer, you stop looking. We don't ever want to stop looking.

And then I went on and on about how science is looking for the best supported explanations. It was just a couple posts ago.

[J.Merrill]

3 hours ago, Phi for All said:

Well, I'll repeat myself, but now you don't get to whine about others not reading what you wrote

And then I went on and on about how science is looking for the best supported explanations. It was just a couple posts ago.

No one is whining at all about anything, but you can have respect for other people. Its a little disrespectful how you talk to me don't you think? Aside from that. 

 I understand this completely, but you are trying to replace Answer with a another word but that word you chose is "Answer".

An explanation is not the same as a proposition, or an argument, or list of propositions; it is an answer.

If one thinks they found an explanation that fits all, then why would there need to be any reason to continue to question?  You would have the full explanation you would have the answer.  

 

But we can't ever have the full "Explanation" Its not possible, that requires a full Explanation from beginning to End. We can only understand a limited amount, and that is even questioned still. 

3 hours ago, Phi for All said:

Well, I'll repeat myself, but now you don't get to whine about others not reading what you wrote

And then I went on and on about how science is looking for the best supported explanations. It was just a couple posts ago.

Science its self doesn't question physically in this context. 

But People question things and using a Method call science we are able to answer things. Maybe I am more clear here.

 

What is Water made of?

Because people questioned that, and through the method of science, an explanation was given, it was the answer. 

Edited June 20, 2022 by J.Merrill

[studiot]

2 hours ago, J.Merrill said:

If I wrote 2 + 2 = 4 

The equation is true, I can apply this equation in physical form too, Two Fish + Two Fish = Four Fish. 

But if I said it was 5 wouldn't that be a flaw?

Not necessarily.

There are 3 axioms of addition

Just for simplicity I will stick with whole numbers (integers)

1) Closure :  If a, b and c are whole numbers and a + b = c then c is a whole number.

2) Commutation  a + b = b + a

3) Association   (a + b) + c = a + (b + c)

None of these define the operation + (that is what I must do when presented with a form a + b

Suppose I define that operation to be a + b = (a + b) + 1 ?

Then 2 + 2 = 5

It is easy to show that this operation satisfies all 3 of the axioms of addition.

[Phi for All]

50 minutes ago, J.Merrill said:

An explanation is not the same as a proposition, or an argument, or list of propositions; it is an answer.

How can the best current explanation be the answer to a question when the explanation could change with new information? Perhaps this is just semantics, but to me an "answer" is going to be the same today as it was a hundred years ago, or a hundred years from now. "Four" is an answer to "What is 2+2?"

The explanation for how allele changes within a population over time can cause evolutionary changes in a species is never going to be an answer. It's always going to be a vibrant, maturing theory that explains the process to best of our current knowledge.

[NTuft]

@J.Merrill
On 6/19/2022 at 12:41 PM, J.Merrill said:
o argue this as you have quoted me, is to argue Einstein.

On 6/19/2022 at 8:07 AM, J.Merrill said:
ts previous state,  into its unbent position?

"XXVII
THE SPACE-TIME CONTINUUM OF THE GENERAL THEORY OF RELATIVITY IS NOT A EUCLIDEAN CONTINUUM
...Gauss co-ordinates...
XXVIII
...The following statement corresponds to the fundamental idea of the general principle of relativity:
"All Gaussian co-ordinate systems are essentially equivalent for the formulation of the general laws of nature."...
APPENDIX V
...On the basis of the theory of general relativity, on the other hand, space as opposed to "what fills space", which is dependent on the co-ordinates, has no separate existence."
Albert Einstein, Relativity: The Special and the General Theory, MCMLXI by the Estate of Albert Einstein 

answer me again on spherical, elliptical, hyperbolic; positive, less positive, negative. or flat. i can't find where einstein was arguing it was flat.

[J.Merrill]

6 hours ago, studiot said:

Not necessarily.

There are 3 axioms of addition

Just for simplicity I will stick with whole numbers (integers)

1) Closure :  If a, b and c are whole numbers and a + b = c then c is a whole number.

2) Commutation  a + b = b + a

3) Association   (a + b) + c = a + (b + c)

None of these define the operation + (that is what I must do when presented with a form a + b

Suppose I define that operation to be a + b = (a + b) + 1 ?

Then 2 + 2 = 5

It is easy to show that this operation satisfies all 3 of the axioms of addition.

When you solve for one or more variable you need to remember they are placeholders for whole numbers in this case

ill solve for B

b = b +1 

or 1+1

So the same applies for   A 

a = a + 1 

1+1

 

so a+b = (2 + 2) + 1 or 2+2+1 = 5

 

A set of axioms should be consistent; it should be impossible to derive a contradiction from the axioms. A set of axioms should also be non-redundant; an assertion that can be deduced from other axioms need not be regarded as an axiom.

 

In other words no mater what 2 + 2 should always = 4

 

This is not 2 + 2 = 5 

But it was a good example of simple Algebra 

[NTuft]

corrected citation (I can't edit the above):
XXVIII EXACT FORMULATION OF THE GENERAL PRINCIPLE OF RELATIVITY
Albert Einstein, Relativity: The Special and the General Theory: A Clear Explanation That Anyone Can Understand. Crown Publishers, Inc. 1961. 
Pgs. 93-94...97...155

 

Waiting to hear if you can figure the 3-D geometry to use in G.R.

Edited June 21, 2022 by NTuft

[Markus Hanke]

18 hours ago, Eise said:

Where I do not quite agree with Bufofrog that philosophy is the trash can for all questions that sciences cannot answer, he definitely has a point. In philosophy, we say that your kind of question contains a category error. Causality can only meaningfully be defined in space and time. E.g. following statements should clarify this:

• a cause always precedes its effect
• Two events can only be directly causally related when they are in their immediate vicinity 

But such propositions only make sense in space and time, they are meaningless when talking about space and time. Causality does not apply to space and time themselves.

The relationship between spacetime, energy, and gravity is a conceptual one, not a causal one. By giving the conceptual relationships between these three, one could say that the job of the physicist is done. 

As a philosopher, of course one can ask all kind of petty questions ('is space really curved?';'What is ontologically first: gravity or time dilation?'). Physicists can do very well without such questions, and their possible answers. Some of these questions can be fascinating (e.g. PBS spacetime has an interesting episode about the latter question). Exactly these kind of questions show that 'causality' does not apply to spacetime itself.

Great post! +1

I would add here that GR is a description of, rather than an explanation for, gravity - in the sense that it deals only with the dynamics of the metric, but does not suggest an underlying mechanism as to why the Einstein tensor is precisely proportional to the energy-momentum tensor, as given in the Einstein equations. In other words, at present we don’t know yet why the concept of Einsteinian spacetime is such a good description of observable reality. This question falls outside the remit of GR, and would require a model with a wider domain of applicability.

 

On 6/19/2022 at 10:07 PM, J.Merrill said:

But if you take away the mass causing this Warped Spacetime, what causes the "Curved Fabric of Space"  return to its previous state,  into its unbent position?

If you change the distribution of gravitational sources, then the geometry of spacetime will change accordingly, along with it. To be more precise, the changes in geometry will propagate outwards and away from the original position - either as regular gravitational radiation, or simply as unordered wave fronts. These propagate at most at the speed of light, but may propagate at less than c due to non-linear interactions with itself and any background curvature.

In other words, the curvature that was there remains in existence, it just gets distributed differently. You cannot ‘unbend’ curvature, you can only shift it to somewhere else - this is why (eg) you cannot smooth out a sphere into a flat sheet, no matter what you do to it. So asking why spacetime returns into its unbent state is meaningless, simply because that’s not what happens.

[swansont]

13 hours ago, J.Merrill said:

You have even proved my point, we are limited to things we know. And always will be, but how can we accurately compare any model to anything if we don't have a full unlimited knowledge of how it all started and why.

Cause and Effect is a thing.

You are misrepresenting this, though. Cause and effect is a thing, but that means the cause must precede the effect. It doesn't mean you can't study the effect if you don't know the cause, and it doesn't mean that there are no uncaused things. 

Knowing the cause makes for a more complete model, but models are built in physics without having "a full unlimited knowledge" of what's going on; I think it's safe to say that all models in physics are made without this full unlimited knowledge.

[studiot]

28 minutes ago, swansont said:

You are misrepresenting this, though. Cause and effect is a thing, but that means the cause must precede the effect. It doesn't mean you can't study the effect if you don't know the cause, and it doesn't mean that there are no uncaused things. 

Knowing the cause makes for a more complete model, but models are built in physics without having "a full unlimited knowledge" of what's going on; I think it's safe to say that all models in physics are made without this full unlimited knowledge.

Even that is not so cut and dried it is not arguable.

Without the output, in regenerative feedback, the phenomenon could not occur.

🙂

[swansont]

1 hour ago, studiot said:

Even that is not so cut and dried it is not arguable.

Without the output, in regenerative feedback, the phenomenon could not occur.

🙂

Which phenomenon?

[J.Merrill]

4 hours ago, studiot said:

Even that is not so cut and dried it is not arguable.

Without the output, in regenerative feedback, the phenomenon could not occur.

🙂

 

5 hours ago, swansont said:

You are misrepresenting this, though. Cause and effect is a thing, but that means the cause must precede the effect. It doesn't mean you can't study the effect if you don't know the cause, and it doesn't mean that there are no uncaused things. 

Knowing the cause makes for a more complete model, but models are built in physics without having "a full unlimited knowledge" of what's going on; I think it's safe to say that all models in physics are made without this full unlimited knowledge.

Sure I can study things with out knowing the cause, and I can even come up with conclusions based on things that exist now with out knowing the cause. But I certainly can't know the origin of these are true with out the Input. I can only speculate and try to understand with a Reasonable Explanation . But any one can explain something with observations they have made. And their explanation is only limited by their understanding. Religion and science both offer explanations for why life and the universe exist. Science relies on testable empirical evidence and observation. Religion relies on subjective belief in a creator.

Before science was widely excepted as a method of approach to explain things, we had religion for what ever that is worth, because it was the best explanation we had for things we didn't fully understand at the time.

Cause and Effect.

People noticed things around them, and they thought of an origin based on observations and things they had limited knowledge about and that origin was a creator. 

 

Do we still not do that till this very day? But in this case it's science that is the method instead of religion.

We are in attempt to understand things around us that we have a very limited understanding of still, although we gather and acquire knowledge  based on things we see and we used methods to replicate these conclusions in order to test for the same result. And in doing so have a valid Idea that something exist. This is why its impossible to Prove and Disprove somethings, so eventually those things start being looked at as unreliable source of explanation. Like religion why? Because there are things Religion does not explain, but that doesn't make it not true. Just like I cant prove or disprove the big bang, but that doesn't make it not true either.

 

What is true and will always be true is we will never know.

 

So I think at this point we are in agreeance, in one form or another. 

[Bufofrog]

11 hours ago, J.Merrill said:

When you solve for one or more variable you need to remember they are placeholders for whole numbers in this case

ill solve for B

b = b +1 

or 1+1

What is that suppose to show, besides b does not equal b?

[J.Merrill]

3 hours ago, swansont said:

Which phenomenon?

Any phenomenon or event.

You can apply this to anything.

(I.E) The mathematical construct of numbers would not be a thing if humans did not occur.

The birth of human children could not occur with out them either. Even if we some how started growing full sized people in giant glass jars. This cant occur with out humans. 

 

3 hours ago, Bufofrog said:

What is that suppose to show, besides b does not equal b?

lol did you read the post I responded too, it makes more sense if you do. 

it was a counter argument to 2 + 2 can = 5

But that equation is misleading as a and b are both = 1+1 or just 2, and the equation is 

a+b = (a+b) +1 

this is the same as saying (2+2)+1

simplified is (4) + 1 = 5

 

Edited June 21, 2022 by J.Merrill

[swansont]

1 hour ago, J.Merrill said:

Any phenomenon or event.

The question wasn't directed to you. I was asking studiot for clarification.

1 hour ago, J.Merrill said:

 

Sure I can study things with out knowing the cause, and I can even come up with conclusions based on things that exist now with out knowing the cause. But I certainly can't know the origin of these are true with out the Input. I can only speculate and try to understand with a Reasonable Explanation . But any one can explain something with observations they have made. And their explanation is only limited by their understanding. Religion and science both offer explanations for why life and the universe exist. Science relies on testable empirical evidence and observation. Religion relies on subjective belief in a creator.

I thought we were to leave religion out of it.

1 hour ago, J.Merrill said:

We are in attempt to understand things around us that we have a very limited understanding of still, although we gather and acquire knowledge  based on things we see and we used methods to replicate these conclusions in order to test for the same result. And in doing so have a valid Idea that something exist. This is why its impossible to Prove and Disprove somethings, so eventually those things start being looked at as unreliable source of explanation.

 

Disproving things is fairly straightforward in science, at least in principle. It's why we prefer specific, quantifiable predictions rather than vague ones, and why we want prediction and try not to rely on just explaining observed behavior.

 

 

[zapatos]

2 hours ago, J.Merrill said:

Just like I cant prove or disprove the big bang, but that doesn't make it not true either.

What do you mean you can't "prove" the BB. We observe it happening. We named it the BB. It is happening right now. 

[mistermack]

I still think that the OP's picture of  a static picture of curved fabric of space in a gravitational field is not what's happening. If you take any point in the universe, any inertial frame at that point will be accelerating, depending on the strength and direction of the gravitational field at that point. 

Take the surface of the Earth, every inertial frame at the surface will be accelerating downwards, at 32 ft/sec/sec. And any object in that inertial frame will also accelerate downwards at the same rate, if no force is acting on it. It's easy to test that, by jumping off a cliff. 

So if you are talking about the "fabric of space" then you can't maintain that it's static and curved, when inertial frames are accelerating everywhere. If space has a fabric at all, it's the bit that defines the motion of an inertial frame. 

So if you take a photon passing by the Earth, up by the space station, then it's experiencing a constantly changing acceleration towards the centre of mass of the Earth, because at any point the inertial frame that it's in is accelerating. But it's going so fast that it's route is only slightly altered as it passes by. When the same thing happens on cosmic scales, you get gravitational lensing.

[studiot]

3 hours ago, swansont said:

The question wasn't directed to you. I was asking studiot for clarification.

I'm sure you know about regenerative feedback.

The output is different from what it would otherwise be in the absence of feedback.

But unless you have an output you have no feedback.

You can call the regenserative feedback the phenomenon or just the output to suit yourself.

[J.Merrill]

7 hours ago, zapatos said:

What do you mean you can't "prove" the BB. We observe it happening. We named it the BB. It is happening right now. 

No this is not accurate at all.  We are observing conditions that lead us to believe the big bang is a possible origin of the Universe. 

The statement we can prove the BB is false. 

It is yet another answer to things we have limited knowledge to. This cannot be argued I'm sorry.

 

We could say the entire universe is spinning on a disc trapped inside a sphere, and things that were in the center slowly gravitate outward, things closer to the the edge move faster than the center. 

We can do experiments with objects and spin, to confirm some of these effects. But just because it works and observations match part of the assumptions doesn't mean anything. 

7 hours ago, swansont said:

 

I thought we were to leave religion out of it.

 

I actually don't mind, talking about it in this kind of context, but is some one is going to try insult me with it saying " this sounds like some religious guilt"  Id prefer not to use it in that context, but nothing I said was offensive here. 

 

If some people on this forum really want to just simplify reply's down to ad hominem. It truly shows the extent of their own capability to have a meaningful debate or casual conversation. 

 

Edited June 21, 2022 by J.Merrill