Is There Something Beyond?

[Colmc54]

I am a vet. Yesterday I had the horrible duty of putting down my own pet. Over the deacades of my workI have searched for the answer to my question by reading many scientific texts beyond my own specialisation. Most of them affirm the positive steps we humans have made in our understanding of the (at the quantum level) somewhat shaky understanding of reality.

It seems to come down to spacetime and the new discoveries of cosmic inflation after the big bang.

When I dug her grave and planted a rose tree over her corpse I asked myself what do we really know, except perhaps an ever-expanding awareness of our ignorance.

[Khandro]

colmc; //Is that our future, or even already our present day?//
That's a very good question - the subject is worth a thread on it's own. It brings to mind the painting by Paul Gauguin inscribed; "Where do we come from? What are we? Where are we going?"
Re. the 'individual v. collective' polemic, I don't believe it is an either/or question, Buddhism teaches (as always), 'The middle way'. We need individuality (not 'ism') and we also need compliance to a collective endeavour .
Someone once thought that if you attached a rock to a stick it was more useful than holding the rock in your hand and the hammer was born, which quickly 'caught on', and led to a rock with an edge and an axe etc. Using tools collectively we are now able to achieve amazing things like building giant aircraft and enormous civil engineering projects, though unfortunately, we seem to be capable of mass destruction too.

[Colmc54]

"Someone once thought that if you attached a rock to a stick it was more useful than holding the rock in your hand and the hammer was born, "

The above got me thinking about angular momentum of all things! The electron has angular and axial (spin) momentum. Photons, although massless, have momentum but in the case of circularly polarised photons shouldn't they also have an angular momentum in addition to hv? If so where does the energy come from i.e. why, once emitted do circularly polarised photons not behave like normal ones as per the Maxwell description?

Off topic I know, I just wondered if anyone might have an answer.

[Old_Geezer]

I shan't speculate as I would most likely be wrong, and embarrassed, but I do sit here wondering if your initial assumptions are correct. I think you'd be better starting a new thread with that as those who may be able to make a stab at an answer may feel they've done with this thread.

[Old_Geezer]

Anyway, back to the original subject, just about anything you read in ChatterBank qualifies as being "beyond". ;-)

[jim360]

I only just noticed your question about angular momentum of light. The answer is that light does have an angular momentum as well as spin, but its orbital angular momentum is not associated with its polarization. The polarization is associated with its spin angular momentum. I'm not sure this is the clearest explanation I've ever given, but it does serve to illustrate how important precision in Scientific language is. Two concepts that are separate but related, if confused and treated as the same, muddy the issue.

[naomi24]

If precision in scientific language is so essential to an explanation, is there any point in using that language where you know few will understand it? It follows that for most, such an explanation amounts to no explanation at all.

[jim360]

I'm guessing from colmc's question that he'll know what most of those words mean. If after all the explanation hasn't helped him I'll try again -- in the end it's his opinion on my explanation that counts the most.

[naomi24]

I think a lot of us know what those words mean, Jim - but I was thinking of those with an interest in science who would appreciate a simple explanation . Anyway, not to worry. I didn't realise you were having a private conversation so I'll leave you to it.

[jim360]

It's not a private conversation, but Colmc asked the question and I was answering him at the time. If you're also interested in the answer I'll try to come up with a better explanation:

The basic point is that there is no link between polarisation and orbital angular momentum. The polarization of light is linked to its spin angular momentum instead, and its (external) orbital angular momentum depends only on where the light is and in what direction it's headed. No extra energy is needed.

[Colmc54]

Maxwell's model of a photon travelling at c from your screen towards your eye, assuming it is vertically polarised in this case, would show the rise and fall above the line of a +ive electric field inducing a corresponding magnetic field to it's RHS, then in the second half of the wave cycle a falling and rising -ive electric field below the line inducing a magnetic field to it's LHS. This cycle repeats endlessly along the line.

What intrigues me is that in circularly polarised light the angle of polarisation is continuously rotating. As yet I haven't had the chance to learn more as to the theoretical basis for why this should be happening to a photon travelling in free space.

Could the recent experiment that appears to confirm that gravity waves curl the polarisation angle of the cosmic background radiation be of some significance in the case of circularly polarised photons?

[jim360]

"Could the recent experiment that appears to confirm that gravity waves curl the polarisation angle of the cosmic background radiation be of some significance in the case of circularly polarised photons?"

I think so -- I'd need to do more reading, but my understanding is that this is basically how it was detected: the gravitational waves leave a distinctive pattern in the polarisation of photons in the Cosmic Microwave Background.

[Colmc54]

Me too. I think once I have I'll open another discussion. The rose bush isn't looking too good now in this heatwave- maybe it's also my fault for going off topic!

[Khandro]

Out of my depth completely, but I'm pleased to think all this resulted from my musings on the origins of the hammer. :0)

[Colmc54]

Due to our wrist action, putting the head of the hammer on the end of a pole makes it's velocity faster relative to the small movement of our wrist. The funny thing I have learned is that when you want to hit the bell in a fairground most of the successful players will take that arc and move the arm along the pole to turn the gained angular momentum in to linear momentum directed down onto the target.

The Heckington show is this weekend. I am almost embarrassed to say that I may have to have a go myself.

[Khandro]

colm; All experienced golfers know the importance of unlocking the wrist in the downswing to gain maximum speed of the club-head (and thereby distance) with the driver.
Good luck, may you ring the bell and win a coconut :0)