Ah, the ol' what is a straight line ploy! But honestly I agree, relatives are everything and could very well be at the bottom of this pile of turtles.

kennyc wrote:Ah, the ol' what is a straight line ploy!

Sounds like your problem is more with math than with physics.

surreptitious57 wrote:To be fair I am thinking of it in two dimensional terms rather than four dimensional ones because it is easier to comprehend it as such. But the fact remains that it is not as nice and neat as drawing an asymptote on a sheet of paper. For one thing that does not take into account the force that can be exerted when at the event horizon or inside a white dwarf or at the centre of any galaxy which is as extreme as it gets. But something which is curved is neat and spacetime is not so that is
my reason for rejecting the definition in favour of warped and which is more accurate for the reasons I have already given

I'm sorry if "curved" is too neat for you, but your rejection of the word is not rational.

DavidMcC wrote:I'm sorry if "curved" is too neat for you, but your rejection of the word is not rational.

There are rational reasons why it's not a good name:
http://www.rationalskepticism.org/physi ... l#p2010109

reksio wrote:

DavidMcC wrote:I'm sorry if "curved" is too neat for you, but your rejection of the word is not rational.

There are rational reasons why it's not a good name:
http://www.rationalskepticism.org/physi ... l#p2010109

Fairt enough, but it's only semantics, after all.

"Okay, but if space is not curved then the force of gravity is acting on the light, the photons which are massless according to current theory. Hmmm...."

Dear Kenny A. Chaffin,

congratulations, You are thinking very far. Indeed it is right, that photons are massless. They have got zero mass, they are "Emission-fields", whereas particles are "mass fields". Therefor Einstein was wrong to postulate light-"particles". This is a very fundamental big mistake, to assume light as particles. Light are no particles, never.
The material of mass (elementary particles) is charge, which causes "space charge density". The space charge density stands at the right side of the inhomogeneous Helmholtz-equation.
For "light" or generally "emission" the homogeneous Helmholtz-equation is valid. Here the space charge density is zero.
So light doesn*t have space charge density and thus no mass.
The third sort of field in our universe is (besides the "mass-field" and the "emission-field") the "gravitational field". The "gravitational field" is directly caused by the "mass-field", whereas the "emission-field" (Quantum) is caused indirectly by the "mass-field" by a "Quantum-jump".
But all of that three fields have got something in common. They all are nothing else than pure energy-density. From this energy-density You can calculate a "force-field" (in other word: gravitational field). That means, the "emission-field" (that physicists erroneously call "photon"), which is massless, is another gravitational field.
In the case, the gravitational field "light beam" is crossing a spherical gravitational field of a body (i.e. the sun), those both gravitational fields are superimposing each other. So, the light beam adopts the form of the gravitational field of the body.
You can calculate that with the Helmholtz-equation, because this equation is the world formula, that Einstein was searching for all his life.
The according mathematics You find in my recently by Amazon or epubli published book:

PHILOSOPHIAE NATURALIS PRINCIPIA MATHEMATICA II
The continuation of physics

ISBN 978-3-8442-7106-5
Author: Arthur Büttgen

Cheers

Arthur wrote:...
But all of that three fields have got something in common. They all are nothing else than pure energy-density. From this energy-density You can calculate a "force-field" (in other word: gravitational field). That means, the "emission-field" (that physicists erroneously call "photon"), which is massless, is another gravitational field.
In the case, the gravitational field "light beam" is crossing a spherical gravitational field of a body (i.e. the sun), those both gravitational fields are superimposing each other. So, the light beam adopts the form of the gravitational field of the body.
...

What does that even mean? ... Oh, wait! ... It means "Buy my book at Amazon"!
Was this another advert by special permission of the mods, I wonder?

If You are satisfied with my verbal answer, then it's okay. But when You really want to understand, I am afraid, You have to calculate and go deeply into mathematics, I'm sorry.

Maybe it's bogus....I'm not finding anything by that name, ISBN or author at Amazon U.S.A.

Arthur wrote:.... photons are massless. They have got zero mass, they are "Emission-fields", whereas particles are "mass fields". Therefor Einstein was wrong to postulate light-"particles". This is a very fundamental big mistake, to assume light as particles. Light are no particles, never......

Don't want to get too far off topic, but how does this jive with the photo-electric effect and QM?

kennyc wrote:Maybe it's bogus....I'm not finding anything by that name, ISBN or author at Amazon U.S.A.

There are other Amazon sites that would be more appropriate than amazon.com, but I don't want to help him plug the book!

Post #15 contains the answer. Or points most accurately toward the answer. Because the answer is in the maths, not in words.

Whoah, careful. Mustn't mention maffs in a physics thread, apparently...

eversbane wrote:Post #15 contains the answer. Or points most accurately toward the answer. Because the answer is in the maths, not in words.

That would be the answer to the OP question, but the thread has moved on from there.

hackenslash wrote:Whoah, careful. Mustn't mention maffs in a physics thread, apparently...

Whoa! My issue isn't with maths, per se, but with the way mathematicians sometimes use it to come up with bad physics.
It's a powerful tool, but one that often gets misused, IMO.

Don't want to get too far off topic, but how does this jive with the photo-electric effect and QM?

This jives with the photo-electric effect in a really phantastic way. Although light doesn't have got mass, it can be able to have enough energy (force) in order to push a particle like an electron out of its orbit. This effect is known as photo-electric effect.
This jives with QM in that way, that QM is wrong in that point. In the standard model of elementary particles one can find the photon as elementary particle. For serious physics they have to erase the photon from the standard model of elementary particles. But that are not the only "particles" that have to be erased. "Quarks", "Neutrinos", "Higgs" and probably many "particles" more have to be erased forever. They simply don't exist.

Do you reject QM (ie, probabilistic physics) altogether, Arthur?

I don't reject QM altogether, but indeed I reject probabilistic physics. Especially the probability of presence in the Schrödinger-Equation I reject. The Schrödinger-Equation is tinkered in order to describe mass. I recommend instead of taking care for the Schrödinger-Equation, you better should solve the Helmholtz-Equation(s).

hackenslash wrote:
Photons are not massless, they have no rest mass. They still have mass associated with
their kinetic energy, and this is indeed affected by gravity, hence gravitational red shift

If they are not massless then what stops them from attaining infinite mass when travelling at light
speed ? Is this because they are sub atomic and general relativity only works at the classical level ?

surreptitious57 wrote:

hackenslash wrote:
Photons are not massless, they have no rest mass. They still have mass associated with
their kinetic energy, and this is indeed affected by gravity, hence gravitational red shift

If they are not massless then what stops them from attaining infinite mass when travelling at light
speed ? Is this because they are sub atomic and general relativity only works at the classical level ?

Off the top of my head;

The relativistic mass increase is a function of the rest mass (from special realtivity). Photons have no rest mass, so therefore there is no increase.

However; the famous formula E-mc2, when looked at more generally is;

E2=m2c4+p2c2

(where m is the rest mass, p is momentum).

For a photon, this simplifies to;

E=pc (because m=0)

It's because a photon has a momentum that we can infer it has a mass.