Buh?
I, err, what?
Microsoft researchers have teamed up with physicists from the University of California, Santa Barbara, to show how time crystals might be possible. First proposed by Nobel-prize winning theoretical physicist Frank Wilczek, time crystals are hypothetical systems that spontaneously break time-translational symmetry (TTS) – a …
Surely some things might fit in both the NSFW and the YBMM categories ? Would some scale not be in order ? For NSFW one might use the feather to chicken scale, for YBMM the something to Hawking scale ? Put one on X and the other on Y, and I for one will skip all articles in the Hawking/Chicken section.
>My understanding of the article, based on the odd word I understood ( eg: "and" ) was perpetual motion.
Me too and then at the end it was mentioned it doesn't break the second law of thermodynamics which means then probably the phenomenon if it exists won't be directly useful to our everyday life for quite some time if much at all. Still worth investigating I suppose or else another Syndrome will rule us all with his zero point energy devices.
"My understanding of the article, based on the odd word I understood ( eg: "and" ) was perpetual motion. So that can't be right then. Anybody?"
Perpetual motion isn't actually impossible. For example, a simple two body system of a moon orbiting a planet will continue in motion forever in the absence of any other forces. In practice, such macroscopic inevitably do have other forces involved - friction in particular being a bit of a bugger - so things mostly come down to reducing them as much as possible and just getting really, really close to perpetual motion. And as it turns out, even in the absence of friction or any external force, relativity says such a system must emit gravitational waves and so over a very long time it will decay and not actually be perpetual.
However, when we go to the quantum scale things, as usual, get a bit weird. An electron orbiting a proton (a hydrogen atom) is similar to the moon/planet system, but it turns out only discrete energy transitions are possible - an electron in the lowest energy state cannot lose any more energy and instead remains in "orbit" around the proton (the orbit analogy is obviously not actually correct, but the important point that the electron has energy and remains in motion is correct). That's what is called the "ground state", and it effectively means that every single atom, or indeed anything composed of more than a single particle, is in perpetual motion.
What this research essentially says is that you can construct a crystal that also has a non-zero ground state energy and so behaves more like one of those quantum systems than a macroscopic system. The important part is says that the system "must never reach thermal equilibrium or radiate heat" - basically you set things up so that it can't ever lose energy, and instead remains in the non-zero energy ground state. In fact, even that isn't considered particularly strange in this field, the weird part is that it's not normally possible for a system in the ground state to spontaneously start doing something. An electron in hydrogen in its ground state was already "orbiting" and simply continues do so, while these crystals are the equivalent of taking a proton and electron with zero energy which spontaneously suddenly start orbiting each other. It's pretty weird even for quantum physics, but doesn't appear to actually be breaking any physical laws.
Getting back to the perpetual motion thing, the reason this is generally the realm of the crackpot is that it's impossible to have perpetual motion and get energy out of the system at the same time. If you eliminate all losses you can have something in motion forever, but as soon as you take energy away it will stop moving. We can't use electrons in atoms as an infinite source of energy because the whole point is that it's impossible for them to lose any more energy. But understanding how electron energy states work has given us things like transistors and lasers, so even though these crystals won't give us any kind of free energy or useful perpetual motion, they could still lead to all kinds of useful things.
I think the gist of it is that someone with a Nobel to their name (and who therefore presumably knows how thin the ice is this far out) reckons they have identifed a system which *in its lowest energy state* is in some sense "in motion". This is apparently a novelty. Furthermore, a group financed by Microsoft is now going to try and create that system to see if the wacky idea is true.
I got as far as crystals which break symmetry in both space AND time dimensions, then my mind started drifting off along a tangent of "do they mean dilithium crystals?" before my train of thought finally reached the terminus at "ye canna break the laws o'physics" and Microsoft having a 'Q' continuum.
OK, here is what is going on. If you have a liquid it looks the same in all directions but when you cool it and freeze it there are certain preferred directions in a crystal lattice. So cooling a liquid "spontaneously" breaks rotational and translational symmetry. Certain directions are preferred for crystal planes and the atoms are now regularly spaced so the probability of finding an atom at a particular place is no longer uniform but a "comb" function.
A time crystal is a material that is not the same at different times. It is like an oscillator that repeats itself so the phase repeats regularly. This is done at the quantum level so that there is no lower energy state to decay into.
This is significant but the term "time crystal" invokes images of time travel etc. but it is really just a quantum oscillator that is in the lowest state. In general, spontaneous symmetry breaking is achieved by cooling.
"They can't even get a web browser to work properly.."
..or a mail service apparently. The new Namesco Demon replacement Office 365 email service's SMTP host blithely includes the BCC list in all the recipients' headers. Fortunately this was reported on a test email - so can be avoided for more sensitive future ones.
I always though Microsoft had fucked around with time. Microsoft seems to waste so much of my time, with their bug ridden software updates.
Microsoft 'Progress' seems to mean 90% software updates (rearranging the chairs, nothing new), 10% meaningful work of late (if I'm lucky) in between the waiting / diagnosing what just failed to update.
Just to say. I understood this article more than Satya Nadella's keynotes.
Maybe they've missed their true vocation all these years? Maybe they were never meant to be a software company - but a cutting edge physics lab?
Be smart, kids - see your local vocational guidance counsellor before deceiding on the career you want to pursue!
And why Microsoft would care, I can't even fathom.
Well, obviously, it's so they can improve the operation of their progress bars.
As we all know, Microsoft employ their own custom time algorithms for calculating the time left for file transfers and downloads: who hasn't seen the "time left" value oscillate between "32 seconds" and "2 days eleven hours and 51 minutes" when copying a file.
However, this is obviously not enough, and the ability to actually stretch and manipulate time to suite their algorithms is eminently more sensible to Microsoft than actually making their algorithms reflect reality.
>who hasn't seen the "time left" value oscillate between "32 seconds" and "2 days eleven hours and 51 minutes" when copying a file.
Activity: copying [by drag n drop] a music folder from HDD to SD card, then dragging over several more folders.
Expected behaviour: First folder is copied completely, then the second, then the third.... then the Nth.
Observed behaviour: Windows attempts to copy files from all folders at once, so the HDD spends most of its time seeking data rather than reading it. "Time left" goes up to days.
Work around: select all desired folders first (holding Ctrl).
Is there a reason MS implemented copying in this way?
"[...] hidden rand() function somewhere - maybe not in the copy function itself, but certainly in the bit that generates the progress bar."
Generating a progress bar is not as simple as one thinks initially. There are at least three variables for any file.
1) the overhead of finding/creating each file in the directory and the resource handshaking needed.
2) the amount of data in the file.
3) the head movement to access the file's data if it is fragmented across the disk.
Small files are particularly affected by 1 - with the actual data transfer being almost inconsequential. The same overhead on large files would be smaller compared to the time taken to transfer its data. However a seriously fragmented large file would then be slowed down by random head movements.
As large folder copies have files that are rarely homogeneous in respect of 2 and 3 - then the above effects would make it difficult for any progress algorithm to extrapolate based on the total number/size of files it has already transferred.
Not a programmer I take it?
progress = byteswritten / totalbytes
estimatedduration = totalbytes / byteswritten * elapsedtime
For copying one or more files, that's it. The longer it runs the more accurate and stable it becomes. And it will never, ever go backwards. Fucking this one up is bad enough, but leaving it that way for twenty years is what really beggars belief.