SPACE-TIME DILATION? WHY?

[rigney]

"Because Einstein said so?"! As much as I respect his genius, we succumb to a trap of servitude at his behest. There are many great minds out there today who agree and disagree with Dr. Einstein. But who is right? Few want to move from the status quo, so remain ignorant of their own potential and genius because of this rigidity, leaving a possible earth shattering expertise in limbo. Just a question though? Do manifolds and tensors actually apply to "Time and Space Dilation"? If so, would someone please explain them to me: as to Why and How?

Edited February 10, 2011 by rigney

[ajb]

I am not sure what you are asking for.

 

But does "Time/Space Dilation" have anything to do with manifolds and tensors? If so, how and why?

 

Classical space-time as we understand it today has everything to do with differentiable manifolds and tensor fields on them.

 

Intuitively the reason is that physics should not depend on exactly how you chose to describe it. Mathematically this is encoded into differentiable manifolds and tensor fields in terms of changes of coordinates.

 

Tensors (their components) have a very nice transformation rules. The important thing is that equations between tensors do not change their form under changes of coordinates. This tell us that such things are greatly suited to describe physics, quite independently of Einsteinian relativity.

 

Few want to move from the status quo, so remain ignorant to their potential because of this rigidity, leaving many brilliant minds in limbo.

 

I think that every physicist would love to find a discrepancy in special or general relativity. Doing so maybe necessary in getting hints on quantum gravity, for example.

Edited February 10, 2011 by ajb

[imatfaal]

not because Einstein says so - but because it explains the known facts better than anything else.

 

few physicists wouldn't jump at the chance of expanding upon or even overturning einstein (the nobel prize money would be nice for a start) - the trouble with that plan is that einstein's conceptions tally remarkably well with a myriad of experimental data. To challenge einstein's work requires more than a general disquiet and unease about the possibly counter-intuitive conclusions - one would need either to show a situation in which predictions fail, or a complete new theory that not only explains everything as well as einstein's work it must also go beyond and explain other stuff.

 

it is a common fallacy that science sticks with theory through some outdated adherence to dogma and over-respect for the status-quo - perhaps this was once true but in modern science as soon as a theory stops making provable predictions there are a pack of new ideas ready to replace it

[rigney]

Today, 10:36 AM ajb: I think that every physicist would love to find a discrepancy in special or general relativity. Doing so may be necessary in getting hints on quantum gravity.

 

Since I simply don't have the wherewithal to disagree with you, may I ask: What is gravity? I'm not a professenial, yet I've read and heard so much about it that I'm green with envy. Still, it is as elusive to me as a "Will-o'-the-wisp". Personally, I believe it is nothing more than an extension of magnetism, but that is only an opinion. Would you try driving the concept of "Gravity" into my head to where this shallow mind might understand it? I thank you.

Edited February 10, 2011 by rigney

[ajb]

What is gravity?

 

Gravity is the phenomena of attraction between massive bodies.

 

Would you try driving the concept of "Gravity" into my head to where this shallow mind might understand it? I thank you.

 

According to our best model of the gravity, i.e. general relativity gravity is identified with the local curvature of space-time.

[rigney]

Gravity is the phenomena of attraction between massive bodies.

According to our best model of the gravity, i.e. general relativity gravity is identified with the local curvature of space-time.

 

Why just massive bodies? And then, depicting gravity only in reference to expanding space-time? These are just questions that without mathematics I wiil likely never understand. Even with the math I would probably still shake my head in disbelief.

Edited February 10, 2011 by rigney

[ajb]

Why just massive bodies?

 

As far as we know all "lumps of stuff" have mass. I don't know of any massless bodies.

 

Of course we later realise that it is the energy-momentum that is important and massless particles, like light do interact gravitationally.

 

And then, depicting gravity only in reference to expending space-time? These are just questions that without mathematics I wiil likely never have answers. Even with the math I would probably still shake my head in disbelief.

 

If you are looking for a deeper understanding of nature you will have to embrace mathematics. I cannot see any other way.

[rigney]

As far as we know all "lumps of stuff" have mass. I don't know of any massless bodies.

 

Of course we later realise that it is the energy-momentum that is important and massless particles, like light do interact gravitationally.

 

If you are looking for a deeper understanding of nature you will have to embrace mathematics. I cannot see any other way.

 

If gravity's effect works equally on everything, why isn't Jupiter, Saturn, Uranis and Neptune simply massive planets rather than gas giants? They all have a huge center mass. Just a question?? Edited February 12, 2011 by rigney

[ajb]

If gravity's effect works equally on everything, why isn't Jupiter, Saturn, Uranis and Neptune simply massive planets rather than gas giants? They all have a huge center mass. Just a question??

 

That is a question about planetary formation. I think the gas pressure is balancing with the gravitational collapse.

[rigney]

That is a question about planetary formation. I think the gas pressure is balancing with the gravitational collapse.

 

ajb, As I have related in several earlier posts, my schooling in astrophysics started about 70 years too late. Math in any form?, even farther back. As much as I've read on the subject, my ignorance somehow doesn't let me relate to "gravity". And while the Higgs boson may never be more than a theory, I find its concept and rationale much easier to understand than gravity. Kim Griest from UCSD Phy Sci gave a fine talk on the Higgs boson. I had put this in an earlier post which you may have seen or even knew the particulars of beforehand. But to me there has to be a reason for a beginning and this fits the bill. Strange, how we take so much for granted.

 

Empty space!

http://documentaryheaven.com/the-mystery-of-empty-space/

 

Gas giants

http://en.wikipedia.org/wiki/Gas-giant

Edited February 12, 2011 by rigney