Page 2 of 4

Posted: Mon Jul 01, 2013 5:07 pm
by Vraith
peter wrote: How is this squared with questions of 'why are we here'? I would like to ask Hawking to explain that comment to me.
Huh...me, too, since it doesn't seem to line up with much he's said [including, but not limited to "philosophy is dead."].

Unless he meant the distorted kind of "why,"...a complete explanation contained in pure mechanisms, the how and what and such.

If he meant why in the "purpose" sense...well, he got some 'splainin to do.

Posted: Mon Jul 01, 2013 5:32 pm
by Hashi Lebwohl
Science cannot answer the question "why does x exist?" because that is not its reason for existing. Science exists to answer the question "how did x happen?"

"Why?" is answerable only by philosophers and/or theologians. The problem with that, of course, is that the answer that suffices for Joe Schmoe isn't going to suffice for Jane Q. Public.

Posted: Mon Jul 01, 2013 6:03 pm
by wayfriend
And yet we can answer questions such as "why do cars exist?"

Perhaps there is a belief that, although there is no god, there is a someone with intentions involved. Which is what I believe myself, as I have posted before.

Posted: Mon Jul 01, 2013 7:18 pm
by Hashi Lebwohl
Yes, but do the cars wonder why they exist?

Posted: Tue Jul 02, 2013 4:51 am
by Avatar
The why answer is actually very simple. But it doesn't satisfy people who have confused cause and effect with intent and projected it onto a macroscopic scale.

The answer, of course, is because.

--A

Posted: Tue Jul 02, 2013 9:42 am
by peter
The program had some truly astounding computer visualisations of what the universe looks like as a whole - how absolutely crammed it is with galaxies once you get outside the relative emptiness within galaxies them selves. The universe, if it indeed looks like this from 'outside' is a truly, truly beautiful thing (and in no means difficult understand why people sucumb to the idea of a 'creator'). A glittering web of lights, swirls, eddys and coruscations fit to make the hardest heart swell. If that image alone were the only thing science had come up with it would be enough.

Hawking was somewhat blase about the existence of life - in the case of multiple universes (infinite actually) it was not only probable, but certain that in one of them all the conditions for life to evolve would be satisfied - and here we are, a consequence of that certainty. Life he said, seems to be the natural way that matter organises itself given the conditions that pertain in our neck of the woods in our universe with it's specific set of 'constants' etc.

Posted: Fri Aug 30, 2013 11:36 pm
by Menolly
Image
"I do not see him here or there.
I do not see him anywhere.
I think he may be in that box,
introducing me to paradox.

I think that cat,
he may be dead,
lying in his cardboard bed.
In the box he would not thrive,
but chances are he’s still alive."


Description and design by: Nathan W. Pyle

Posted: Fri Aug 30, 2013 11:51 pm
by lorin

Posted: Sat Apr 05, 2014 3:32 pm
by Vraith
I put this here cuz of the Cat, of course...always blame the Cat.

It has connections to other threads....somewhere, maybe a couple wheres, the P/NP problem has come up before....

So here's a claim that connects the P/NP in order to shed light on why quantum things, like the Cat, don't appear on the macroscopic scale.

The short of it [a spoiler, I suppose] is that if P does NOT equal NP, which almost everyone thinks is the case even if not proven yet, then that draws a line between quantum and macro scales. [I'm not quite getting all the explanation yet, probably never will...and I haven't checked the reputation/reliability of the source or author]

Take a gander, it's not really long:

https://medium.com/the-physics-arxiv-blog/7ef5eea6fd7a

Posted: Mon Apr 07, 2014 9:13 am
by Hashi Lebwohl
Now we need only hunt down Bolotin's actual paper to read it for ourselves. That link at the bottom may be to it but I'm not to look into it at 0415--it's too early for that.

Fascinating stuff, though. I have often wondered about how large something has to be to jump from quantum to Newtonian.

Posted: Wed Apr 09, 2014 11:48 am
by peter
Buckyballs?

Posted: Wed Apr 09, 2014 2:55 pm
by Vraith
nice guy peter wrote:Buckyballs?
I'm pretty sure I recall from somewhere that buckyballs up to around 60-ish atoms have shown quantum behaviors. [[I'm also pretty sure somewhere around here someone...maybe it was even me...mentioned the largest thing so far was 120some-ish atoms?]]

Posted: Thu Apr 10, 2014 12:50 pm
by peter
When such things show 'quantum' behavior, do they do so exclusively? I mean are 'quantum behavior' and 'non-quantum behavior' exclusive in their demonstration or is there a sort of 'middle-ground' where objects show some quantum and some non-quantum properties?

Posted: Thu Apr 10, 2014 2:58 pm
by Vraith
nice guy peter wrote:When such things show 'quantum' behavior, do they do so exclusively? I mean are 'quantum behavior' and 'non-quantum behavior' exclusive in their demonstration or is there a sort of 'middle-ground' where objects show some quantum and some non-quantum properties?
That's a very good question, with some odd implications, and I don't know.
My suspicion is the last. I also suspect a context/conditional/contingent aspect...quantum behavior/characteristics in some environments/situations, no such possibility in others.

But it's just guesswork.

Posted: Thu Apr 10, 2014 3:05 pm
by Hashi Lebwohl
That critical threshold is something like a "repelling point", a concept which may be a little difficult to explain without diagrams. Imagine a cone sitting on its base with the apex pointing up and now imagine that the surface of the cone is frictionless--any point on it slides towards the floor. If you were on the apex itself you are at a stable point and you wouldn't move anywhere. If you were near the apex you would begin sliding towards the floor, away from the apex. The apex is a repelling point--anything near it move away from it.

The threshold between quantum and Newtonian is a repelling point--if you are only close to it, one way or another, the laws of physics "push" you away from the threshold so that only one type of behavior is expressed. As Vraith notes, there may be circumstances under which one behavior is expressed and then under a different set of circumstances another behavior is expressed, but nothing ever stays on the threshold itself.

Posted: Fri Apr 11, 2014 8:17 am
by peter
Can I just clarify something; should 'quantum behavior' and 'non-quantum behahior' be seen in relation to each other as 'Newtonian' is to 'Einsteinian' [?] - ie mutually exclusive explanations of how particular phenomena opperate. Or is there a [sort of] 'continuum' from 'quantum' for the very, very smallest stuff going up to Hashi's 'repelling point' beyond which everything is 'non-quantum'. Ok - lets put it better; can the very, very small stuff be described in non-quantum terms [as all motion can be explained by Newtonian mechanics] but just with a 'less good fit' than is given by the quantum explanation?

Posted: Fri Apr 11, 2014 3:43 pm
by Vraith
nice guy peter wrote: Ok - lets put it better; can the very, very small stuff be described in non-quantum terms [as all motion can be explained by Newtonian mechanics] but just with a 'less good fit' than is given by the quantum explanation?
SOME things, kinda-sorta. Like, when I was first learning chemistry, they were still showing/explaining atoms with little electrons orbiting like tiny planets, and H20 was drawn like little Mickey Mouse ears. They were doing that even though they'd known for decades that is was not the way things work. But you can still do quite a few cool things with chemistry thinking of it that way. Below that "size,"...I don't think there's anything you can do/describe/calculate/predict, even in the roughest ways, with Newtonian explanations.

As it stands now, quantum and classical are mutually exclusive...enormous amounts of brain, computer, and experimental power are being used to [re]solve this.

It seems people are trying to find out the answer to continuum or not, too...
my impression is that it is neither a true continuum nor a single boundary...it's more like three "zones". An absolute line below which it is all quantum, an absolute one where it's all classical, and a small area between where for some things, under some conditions, either can work/happen.

Posted: Mon Apr 14, 2014 10:44 am
by peter
Very much a case of 'watch this space' then.

Posted: Wed May 27, 2015 9:00 pm
by Vraith
These seem to fill up some of that watched space [though be careful watching, peter---you are determining outcomes by watching, and if I see you observe something in a way I don't like, I might just observe things you don't want seen by means you won't like... :biggrin: ]

This one is another test passed on the path to quantum cats...and in reverse from similar confirmations.


www.sciencedaily.com/releases/2015/05/150527103110.htm

And this one, mathematical, and in need of examination/discussion which it will almost certainly get, takes a step toward Unification...quantum entanglement [if there's anything that seemed to annoy Einstein more than God playing dice, it was "spooky action at a distance."], if I'm understanding correctly, not a weird outcome/feature of reality but deeper, fundamental, that underlies and naturally gives rise to spacetime at the macro level.
Using a quantum theory (that does not include gravity), they showed how to compute energy density, which is a source of gravitational interactions in three dimensions, using quantum entanglement data on the surface. This is analogous to diagnosing conditions inside of your body by looking at X-ray images on two-dimensional sheets. This allowed them to interpret universal properties of quantum entanglement as conditions on the energy density that should be satisfied by any consistent quantum theory of gravity, without actually explicitly including gravity in the theory.
www.sciencedaily.com/releases/2015/05/150527112953.htm

Posted: Thu May 28, 2015 8:24 am
by peter
This, in a sense, explanation of the holographic theory would apply to conditions at the edge of the universe would it not and lend weight to the idea of our 3 dimensional universe being a projection of 2 d events at its edge. I was supprised by the choice of phrase about reality not existing in the quantum world if you were not looking at it, in the first link and wondered if the words "in the way we understand" should not have been in there, but the work did seem to lend weight to the quantum part of the quantum/relativity problem being pretty much correct. Does this imply that it will be the relativity part that will need tweaking to achieve a GoT, or does the work described in link 2 move it all beyond that by describing as implied a deeper reality level.

[nb. I'm posting from my new 'tablet at present and am not used to the touch-screen keyboard so expect all kinds of weird 'typos' in the coming weeks as a result]