General relativity, will we learn otherwise?

[Smokinjoe9]

"General relativity is a geometrical theory which postulates that the presence of mass and energy "curves" spacetime, and this curvature affects the path of free particles (and even the path of light)."

 

Sorry, I just thought I would ask. I don't like the above statement, it seems to fit the present research, but I find it hard to believe(no need to explain, I get it It's just, well, too old). Like occams razor, yeah a straight line from point a to b is the simplest, no need for more lines, blah, blah.. That's hundreds of years old...Sorry, I am not smart enough to come up with a new/better provable theory, but I don't have to like the old ones either.

[GAHD]

Best explanation I've seen so far, though some of the extrapolations end up looking more like curve balls.

[GAHD]

a bit of clarification: by proven wrong I mean it will be replaced by something more right.

[Smokinjoe9]

I shouldn't have said proven wrong thats harsh. I also meant replaced by something better. I understand it seems like that just won't happen, but I find that hard to comprehend seeing how far we've come. I understand that the current set of rules may have to be scrap piled or altered, but someone has to do it and I would guess it's on the horizon...

[C1ay]

That's hundreds of years old...Sorry, I am not smart enough to come up with a new/better provable theory, but I don't have to like the old ones either.

You do realize that GR is not yet 100 years old.

[Smokinjoe9]

You do realize that GR is not yet 100 years old.

 

Yes, but Occams Razor is....

[Kirk Gregory Czuhai]

Yes, but Occams Razor is....

Occams Razor is a nice principle to use to estimate things (when it can be used) with, but there is absolutely no proof that the universe to be described in the widest domain of its variety will follow its principle.

[C1ay]

Yes, but Occams Razor is....

So, if you don't like Occam's razor because it's hundreds of years old, why are you picking on relativity when it's still comparatively young? Is it the old you don't like or the new? BTW, what does age have to do with it. Pythagoras' theorem is 1000s of years old, should we throw it out too?

[TeleMad]

Occams Razor is a nice principle to use to estimate things (when it can be used) with, but there is absolutely no proof that the universe to be described in the widest domain of its variety will follow its principle.

 

There's probably an actual example of this we can point to (may be many more).

 

When physcists were working out the details of neutrinos the SIMPLEST model that fit all the current data had them being massless. But after a while evidence accumulated (such as that based on the solar neutrino problem) that showed they have non-zero mass. Scienstists COULD have assumed a small but non-zero mass to start with, but that wasn't the simplest possible explanation.

 

So Ockham's razor is more of a guide, or a tool for tentatively concluding which of multiple explanations is prefered, than it is a rule that must be strictly adhered to in order for something to be valud.

[TeleMad]

I shouldn't have said proven wrong thats harsh.

 

As so often happens with polls, the array of possible choices is incomplete and/or biased.

 

General relativity is most likely here to stay. It may be extended (kind of how Einstine extended, but did not refute, Newton's mathematical descriptions of space and time and gravity) but it's not likely to be flat out proven wrong.

 

In my opinion, general relativty is here to stay. The only real problem that I know it faces is being merged with quantum mechanics for special cases such as things described as singularities, but string theory offers a possible way out of that dilemma.

[Qfwfq]

Pythagoras' theorem is 1000s of years old, should we throw it out too?

Of course we should!!!! It's only valid in the very special case of flat euclidean manifolds. Unless the geometric interpretaiton of GR is "wrong" this would mean the Pythagors theorem is valid only in absence of gravity.

 

The matter is subtle. If the overall global topology of the universe turned out to be open, the space-time curvature is but a coordinate choice. There would be no other distinction of it being an actual reality unless the proportionality of gravitational and inertial mass turned out not to be perfectly exact.

[paultrr]

One thing that is showing up in different forms out there is non-linear terms being added into the scalar curvature aspect. One case(see: http://xxx.lanl.gov/PS_cache/gr-qc/pdf/0505/0505063.pdf ) utilizes a variant off of GR. The interesting aspect is in this method one gets a source for inflation in the young universe and a later stage old universe where accelerated expansion holds. But the sacrifice is that the equation of state for the universe is itself a variable then. I've been rather interested if anyone knows of simular ideas using regular GR itself.

 

Reason I ask is I have been suggesting for a bit to some of my friends who favor PV that the assumption that spacetime is flat to begin with might be a wrong approach and that we should try doing models that have a background curvature which varies from point to point due to the presence of matter from that background curvature. The normal accepted logic on the original M&M experiments and redo's is that they always got a null result. If one actually reads the published results on any of them none of them where exactly null. They where close to such with a difference of about 8 m/s. Add to this the Pioneer data on a slowdown which rather translates to something being amiss and you get some reasons to question the standard model a bit. The SM on gravity has spacetime as flat. Einstein's original had spacetime flat and devoid of matter which he later modified a bit since he started with a static model. Almost all varients on GR utilize a flat model for spacetime. What I noticed is if spacetime is not exactly flat then its possible to predict things like that 8 m/s difference and even predict something like the Pioneer effect.

 

By the way anyone can read about the M&M results and every result from any experiment of a simular type since then. The 8 m/s difference is usually attributed to measurement error range which it could well be. But a non-null results does show up within that error range in all of them. The Pioneer effect is rather akin to a test along M&M lines being conducted with a measuring point on earth and one way further out in space. It gets an 8 km/s slowdown rate aimed sunward difference between here and there. They measure that difference via radio signal timing(Doppler effect included). To me this whole thing has suggested there may be some modification to GR needed. One possible approach would be to consider spacetime as having a natural curvature to begin with and another would be a non-linear term added into the equations that varies it all over time.

[paultrr]

Of course we should!!!! It's only valid in the very special case of flat euclidean manifolds. Unless the geometric interpretaiton of GR is "wrong" this would mean the Pythagors theorem is valid only in absence of gravity.

 

The matter is subtle. If the overall global topology of the universe turned out to be open, the space-time curvature is but a coordinate choice. There would be no other distinction of it being an actual reality unless the proportionality of gravitational and inertial mass turned out not to be perfectly exact.

 

Correct me if I'm wrong but from memory I think there has been a few articles appearing as of late beginning to challenge that last part some what or at least suggesting some ways to test it further. I do not think any of them to my memory has offered direct proof that proportionality is wrong. But it has at least begun to be questioned a little.

 

But I would agree about what you said concerning Pythagors theorem. One a simular note name one natural frame where gravity is absent anywhere in the known universe.

[C1ay]

But I would agree about what you said concerning Pythagors theorem. One a simular note name one natural frame where gravity is absent anywhere in the known universe.

Well. SmokinJoe did say old stuff is bad and there's no question that gravity is probably as old as the universe so we should probably thow it out as well.

[Smokinjoe9]

Well. SmokinJoe did say old stuff is bad and there's no question that gravity is probably as old as the universe so we should probably thow it out as well.

 

I didn't say it was bad, hehe, I was just making a statement that maybe science would find that the theory might not be as accurate as suggested.

I was just thinking, what if..I mean it is like having one small piece of bad data in computer code. Maybe it gets past you and then you run the program and the error shows itself but goes unnoticed til it's a monster(which usually doesn't take long), sadly output data cannot be trusted and the whole process(including the program) must be done again.

Just thinking that's all...What if.....?

[Mac]

Don't get the wrong idea here. I am not posting this to promote my own views but I have test data that I believe is appropriate to share regarding GR. The data shows that gravity is not a function of curved time-space which functions from the center of mass.

 

http://www.unikef-gravity.com/UniKV2/Gravtesting.htm

[Smokinjoe9]

The data shows that gravity is not a function of curved time-space which functions from the center of mass.

 

http://www.unikef-gravity.com/UniKV2/Gravtesting.htm

 

I looked at the linked page, now please explain it for me(in laymans terms), I am not a physicist, but interested in theory....