If anyone knows of a pre-print of the Lynd paper floating about the net, please inform me. I'd love to read it.

Here.

And a rebuttal is here.

I haven't had time yet to read the paper, but from skimming the abstract and the rebuttal, it doesn't look terribly convincing.

Looks to me like he dropped out of his physics degree before doing any calculus. The paper is more philosophical than physical. Unfortunately, most journalists aren't any better on theoretical physics than Mr. Lynds, so it will probably get some disproportionate press coverage. Just because the idea is new, different, or unacceptable to the academic community, doesn't make it right. Makes a nice story for the silly season though.

Also, Wheeler hasn't weighed in on his side. He just said that 'young new thinkers often "had pushed the frontiers of physics forward in the past."'

Hardly a personal glowing endorsement.

There have been some attempts to create "metric-less" universe models which allow you to get away from the basic dimensions like time and concentrate on "things".

But the maths is insane.

If you really want to read something more thoughtful on time that might make you think, try Julian Barbour's "The End of Time".

From the article:

"philosophers and physicists have not been able to explain [Zeno's] paradoxes away"

A rather ridiculous thing to say, given that Zeno's pardoxes rely on the false assumption that adding 1/2 + 1/4 + 1/8 ... etc. infinitely adds up to inifinity, whereas in fact it's obvious that the result is less than 1/2.

...the false assumption that adding 1/2 + 1/4 + 1/8 ... etc. infinitely adds up to inifinity, whereas in fact it's obvious that the result is less than 1/2.

Actually, the result is more than 1/2, as you can check by looking at the first term of the series.

One, one half, heck, he's within an order of magnitude. Close enough for government schools. ;-)

Anyway, I don't have time to read the paper...

Yes, the series above adds up to more than 1/2, but there are plenty of infinite series which sum to a finite number. The given infinite series sums to a number which gets arbitrarily close to but never reaches quite as much as one=1.

Actually, this is not the bite with Zeno's paradoxes, since he explicitly discussed finite sums arrived at by infinite summations (something goes half the distance, then half the remaining distance (a quarter), then half the remaining (an eighth), and so on.... ). Zeno's point was (against the Pythagoreans) precisely that if there are infinite numbers of locations and moments within finite ranges of time and space then our characterisation of specific moments and places is suspect: pretty much Lynd's point too.

I think Lynds (is he a Peter or a Philip?) is making quite a reasonable suggestion, actually, though it doesn't sound new to me. Philosophers from St Augustine to McTaggart have doubted the reality of time and suggested it does not flow. I have always found the idea of it being a dimension akin to a spatial dimension unsatisfactory. Nobel physics Laureate Richard Feynmann used to ire colleagues by claiming the evidence supported backwards causation (later events causing earlier events) - saying that anti-particles could just as easily be normal particles moving backwards in time.

And as PaulD above says, Julian Barbour has been claiming since the 1980s that the flow of time is an illusion, and that what we have is a set of tightly but not perfectly overlapping pathways through a universe of static states. I'm not claiming to understand him, but that's what I thought the press releases said!

One suspects Wheeler may have been trying to be polite and got quoted as a fan for his trouble. I promise you, if you're in a position to receive random submissions, you can give no rejection so brutal that someone won't take it as a come-on...

Whatever happened to Henri Bergson?

Yes, sorry Guy. Bergson was indeed all over that time-is-weird territory. Haven't read even snippets of Bergson, though, I must admit.

Thanks for the link. I'm reading the paper now. I'd personally always thought the answer to Zeno's Paradox was that time and space are quantized and the his infinite summation is therefore not applicable. Or looked at another way, you arrive at 1 due to quantitization round off error of that big computer in the sky :-)

Okay, I've read the paper and I agree with the verdict that it is interesting. I'm not sure I agree with the as yet unpeer reviewed rebuttal, nor am I sure I agree with Lynd.

He does seem to have a way around some very troublesome problems that led Deutsch to his multiverse. Whether or not the logic falls apart if analyzed very closely is something I don't feel like doing at 2am, and besides I'd rather read the followup papers and see where it leads.

Like most interesting ideas, it probably leads nowhere. But, hey, that's life.

After sleeping on it, I've thought of another interesting point. Calculus agrees with Lynd. For those who are familiar with the basis of Integration, it has to do with summing a set of rectangles to get the area under a curve. Given y = f(x), the rectangles are Dx * f(xi). The rectangle is an approximation to the curve, but in the limit as DX approaches 0, the approximation approaches the exact answer. If you understand that, you understand most of calculus.

This is important. DX can never *be* equal to zero. If it were, we get 0 * f(xi) which is identically zero and summing an infinite number of zero values gives you zero area: obviously the wrong answer. That is why the DX approaches zero. It may come arbitrarily close but never exactly occupy zero width about the point f(xi

It strikes me this is not very different from what Lynd is claiming has a physical reality.

I'd personally always thought the answer to Zeno's Paradox was that time and space are quantized and the his infinite summation is therefore not applicable.

I've still not read the paper, but I've never even seen why Zeno's Paradox is even a problem, other than as an aside in a real analysis textbook.

See here.