Science And Metaphysics

[Khandro]

I read from, 'Sämtliche Werke und Briefe in Vier Bänden', a biography of the Berlin German woman poet; Mascha Kaléko, that in 1952 she sent one of her poems to Albert Einstein, the opening line was; "Time stands still. It is us who are passing away".
Einstein replied: "I think your poem is very beautiful and rich in meaning. It touches upon a deep metaphysical problem that has become relevant through physics".
What do you think he meant by that?

[solvitquick]

Dear Khandro,
Sometimes I just don't get you in fact most of the time!
Yet another quote! Which may help jomifl but not me!
What the hell does it mean? Why all these quotes? Can't you think and speak as yourself.
I would have thought eternalism was obvious and simply another bit of the nonsenses religionists spout out. Heared of reincarnation, heaven, hell etc.?
SIQ.

[Khandro]

Usually when threads get to be a bit dull (thread worn?) I like to get the boot into old Dawkins to liven things up, but that's no good now as I have an ally in solvitquick.
Perhaps it would be a good moment for me to start to refute Descartes :-)

[solvitquick]

Oh dear, this is gettting tiresome.
Nope another false attribution from Khandro!
I did not "put the boot into Dawkins". I simply said I did not need him regarding my atheism. No commendation nor antagonism towards him!
SIQ.

[jomifl]

Khandro, unless you can break the habit of a lifetime by contributing something positive instead of your usual dissembling your 'friends' will play elsewhere you and you will have to play with yourself.

[solvitquick]

Thanks to the Ab Editor I now have our dear Khandro's address.
I have just sent K. an Xmas Card (guaranteed next-day-delivery).
It came from our last group of Religious Cards which we usually reserve for those nobody people who send us cards and sulk if we do not send them one back.
But that's not targeted at Khandro for that reason - it was just our last card!
It has the 3-alleged "kings", sheep- ermm shearers and a black crucifix.
My Message:
"Dear Khandro Thank You For Your Great Fun, Over The Last Weeks"
He's a great stirrer,
Luv To All and Best Wishes for the Holiday Season,
SIQ.

[solvitquick]

Ignore the false hyperlink - pointless but AB always do that if you mention a person named E etc.
SIQ.

[Khandro]

jomifl; Playing with myself holds no fears for me, - and it wouldn't be the first time :-)
Merry Christmas solvitquick , et tout le monde !

[solvitquick]

Dear Khandro,
Ty for your good wishes to all.
You are a great guy and I am sure I speak for all in wishing you a very happy holiday season. Please keep stirring the pot!
With Kindest Wishes,
SIQ.

[jomifl]

Khando, :o)

[Colmc54]

I think it's equivalent to the question in special relativity concerning whether moving close to the speed of light slows down time itself, or acts directly on objects involved in time-ordered processes such as radioactive decay.

Most, like me would favour the latter over the former, but when we get to general relativity and the revelation that gravitation is a deformation of a ubiquitous material called 'the fabric of spacetime', we have to accept that time has an existence, independent of who or what is going on, as an integral part of that fabric.

Shame the guy I'd most like to take a ride in a lift with died shortly after I was born, so sadly we can't ask him. But it certainly seems likely that this is what makes him say 'has become relevant through physics'.

[Khandro]

colmc54; Welcome to the thread (and to AB!). Some on this subject have had the opinion that he was just being polite, indicating a faintly patronising attitude, which to me would seem out of character. Of course we shall never know, but it is interesting that you feel there are grounds in physics for his reply.

[Colmc54]

Thanks Khandro.
http://en.wikipedia.org/wiki/Einstein_Cross

To me it's one of the most beautiful objects in the sky. That this image exists is yet another proof that gravitational masses like the lensing galaxy in the centre act by altering what I believe E. called the geodesic of spacetime producing a curvature along which light is diverted. Light has no mass so gravity could not affect it's course if gravity is a force acting directly between masses. Thus, whatever it is, the fabric of spacetime must exist and thus time within it.

[jim360]

It's worth pointing out that Newtonian gravity can allow for light to be bent by Gravity -- the reason that gravitational lensing shows that General Relativity is a correct theory of gravity is because it predicts that the bending should be almost exactly twice that predicted by Newtonian gravity.*

(I think it's a sort of naive calculation whereby you say that acceleration due to gravity is GM/r^2 and then try the photon has having a mass m which will go to zero later, and it's all a bit fuzzy and one of these days I'll go through the calculation myself.)

[Khandro]

Fascinating! I've just looked up lensing http://en.wikipedia.org/wiki/Gravitational_lens
So we are looking at four images of the same object simultaneously?

[solvitquick]

Dear jim360,
I don't think I'll be hanging around as this debate is now way out of my scope.
But it would appear that my physics teachers and lecturers were at least partly wrong but that's the beauty of self-critical science.
However your post regarding Newtonian gravity is beyond me as my ancient studies taught me that Newtonian gravity was only about
mass-mass interactions.
Also, I was taught that the photon was without mass, consisting only of energy.
So, given that mass and energy are interchangeable, if the photon's energy is converted to mass is the interchange endothermic or exothermic I wonder.
If you or others dismiss this post as "You just don't get it SIQ" then I will certainly agree but a few comments would be welcome. I've read all the posts including the hyperlink to lensing (wow, very difficult reading) but think I need a simple few comments before returning there, maybe.
With Many Thanks and Respect,
SIQ.
P.S. They thought it's all over, well it's not now! lol.

SIQ.

[Colmc54]

Khandro- That's exactly right, four images of the same object that would otherwise be hidden by the lensing galaxy itself were it not for the curvature of spacetime!

[jim360]

I'll have to get back to you, SQI, as I know that Newtonian gravity can allow for light to be bent but don't fully understand why. From the looks of things it's a sort of cheat, really, by pretending that photons have a mass m that is vanishingly small but non-zero.

[Colmc54]

Mr= Mo/the square root of 1-v^2/c^2

Mr-relativistic mass
Mo-rest mass
v- the velocity of the particle e.g. an electron
c- the speed of light

If the particle is travelling at c then the bottom line reduces to zero which goes into any number or value of Ro an infinite number of times. Hence any particle travelling at the speed of light would have infinite mass. This equation also shows the only way photons of light can travel through the cosmos with the velocity of c is because they have no mass.

[solvitquick]

Dear jim360,
Very many thanks for your answer. As always I can rely on you for an honest attempt to answer what I thought was a dismissable simplistic few queries and statements.
You are a great and patient scientist.
In deep respect,
SIQ.

[solvitquick]

Dear Colmc54,
If the photon has no mass, as I was taught and you appear to agree, how can it be bent by gravity?
Kind Regards,
SIQ.