Calling All Planets

The New Scientist Space Blog pondered here the possibility that the International Astronomical Union might change the definition of planet yet again - promoting Pluto back from "Dwarf Planet" to full planet again. (I confess I'm one of those who don't like the current definition of planet, in particular the criterion of "neighbourhood clearing")

The side effect of one proposed redefinition would be that other objects, such as the asteroidal dwarf planet Ceres and the trans-Neptunian objects Charon (Pluto's "moon" - or one half of the Pluto-Charon double dwarf planet), Makemake and Eris would also become planets, giving us 13 (thus far), and then the blogger Stephen Battersby oh so casually solicited mnemonics for the set of the 13 - and I succumbed, as I have done in the past... (c.f. Googlewhacking which wasted days of... days)

So here they are:

First attempt: nothing special , but a musical theme.

My Violin Exudes Music - Concertos Jostle Sonatas Unborn - Never Played - Charming Melodies Effortlessly

Second attempt: preserves the first two letters of each "planet" name in the mnemonic to help remember which is which (helpful if you are confused by the thought that Eris - the goddess of Discord - would be a better name for the 3rd Rock from the Sun).

Merciful Vera, Eagerly Manipulating Cerebro-spinal Junctions! Sacral Urgences Necessitated Placid Chiropractic Manipulation Erenow!

I am resisting, as best I can, the urge to do one that preserves the 1st three letters of each planet's name.

Mnemonics - Memories are Made of Stuff

Rocketship Dean (Wormholes, Warp Drives and Time Machines - Part II)

In anticipation of the dénouement (what a lovely word!) of the Wormhole-Time Travel thread (see Part I here), I have to describe how one is supposed to construct a time-machine using a wormhole. You may wish to follow the instructions at home...

You will need:

• One Traversable Wormhole (preferably macroscopic) about 1m in length (distance between the wormhole mouths)
  
• One Human-rated rocket ship capable of v~c speed (with supplies and fuel and suitable shielding of course)
• One Wormhole Grapple (ah... yes... how's that work then? Dunno), to be attached to the rocket ship
  
• One set of Inertial Damp(en)ers - lest the pilot be squashed
  
• A willing friend - ideally one who likes travel, for which reason I have selected Dean as Pilot to the Stars (please bring me back a hat from Alpha Centauri...)
• [Yoghurt pots and sticky tape are not strictly necessary, but you never know...]

Instructions:

Ensure the Wormhole Grapple is working and grab one end of the wormhole. Wish Dean luck and launch towards Alpha Centauri at high acceleration so that he very rapidly achieves 0.999998c... At this speed, and assuming the turnaround is quick at the other end (and that he doesn't spend too long haggling for the hat) Dean will be back in what seems to be about a week by his "clock" (just enough time allow him to catch up on some report-writing...) while 8.6 years pass on Earth (but... he'll miss the deadline, won't he? Not necessarily... read on)

Yes, we see the effect of time dilation as we look out of the window at Rocket ship Dean's tail-light... it was blinking once a second before launch, now it is flashing only once every seven and a half minutes.

But wait! Dean's got the wormhole with him... let's take a peek through that! Now, the wormhole is travelling with Dean... there is no relative motion and so, according to most authorities, Dean does not appear slowed down by a factor of 450 when seen through the wormhole. That's not lethargy - it's just intense concentration!

Half way through day 3 Dean looks up and says "I'm here!", nips out, buys a hat, and sets off home again. Three and half days after that he lands. We can see through the wormhole that he is indeed back - but wait! Looking up into the sky in the general direction of Alpha Centauri we see a very, very slowly blinking light. He's still on his way there!

How can this be? Is he indeed the Kwisatz Haderach? No... he's in the future. If he should so wish though, he can step back through the wormhole and as far as friends, family and deadlines are concerned he has been away for only a week, rather than, disappearing without trace for 8.6 years (c.f. "A Quick Trip to Budapest to do some Scribbling")

Likewise, we can go the other way and step 8.6 years into the future (bring back info on the future, clean up on long term investments and the lottery etc....)

No, I'm not making this up (well, not all of it...) here's a respected Professor outlining the same thing [NB I offer this link as it's the only one I know of that has a nice story - the same underlying principles are outlined all over the place]

Well... if you thought quantum mechanics was confusing now you can try getting your head around time-travel and all the attendant paradoxes...

But wait! Is it true? Er... no... or at least I don't think so. The problems are these (and I'm actually neglecting most of the practicalities):

Firstly, relativistic effects - Special or General - apply to separations in spacetime; they do not, as far as I know apply to spacetime. In fact I can't see how they could meaningfully apply.

Secondly, the effects as described would appear to be asymmetrical and suggest that in multiply connected spacetime (that's spacetime with holes in it) most conservation laws go out the window (e.g. if Dean sends me a pencil through the wormhole what 4-momentum (energy +3-momentum) does it have???)

Thirdly, even if a wormhole can move, how does it?

...

Thirteenthly, I forgot to supply a loo for Rocketship Dean.

These and other points will be addressed in due course. Is there a way of restoring equivalence to our inertial frames even in multiply connected spacetime... perhaps - in which case, no time machine can be formed in this way.

Warped space, warped thinking... Paradoxical Stuff.

Aaaa(g)h?

Some time back, while extolling the virtues of an old Black Sabbath CD I said "This is a great CD - each track is even better than the last." To which my witty other half replied "Yes, and when it's finished it will be perfect!"

In light of which, when she said, "You know, when you're not around I think how lucky I am to have you," I couldn't help expecting "- but when you come home..."

"I wish I'd said that....", "You will, you will..."

Funny Stuff

Wormholes, Warp Drives and Time Machines - Part I

Just a quickie, just putting a marker down, a public reminder to do this all better another time.

Don't get me wrong: I would love it if there were such things as traversable wormholes, faster-than-light travel and any way of getting the better of currency fluctuations (such as by going back 12 months and transferring all the money I didn't think I'd need then) but...

It's a big but, and unusually (for this type of casual blog-musing) it's predicated on the idea that Einstein was right... and the "but" in question is...

I don't think so.

Let's do the easy one first: Warp Drive - particularly the Alcubierre drive. The Alcubierre drive is a lovely idea, perfectly in keeping with the idea of a Warp Drive because it does exactly what it says on the tin, it warps space(time). In front, it squeezes it up, behind it stretches it out. But unlike the fictional drive of Zefram Cochrane it's "real" in the sense that it's not just a load of hand-waving and muttering - there's serious maths at work for the Alcubierre drive, which modifies spacetime distances by tinkering with the "metric" - that function of spacetime that says how far apart things are.

This so called metric-engineering is neat and, if one puts aside the "minor problems" ahem of the energy requirements, dealing with incoming photons etc. (apparently another metric tweak will deal with them though) and how one gets into or out of the "warp bubble", it is very, very straightforward: as many light years as you want in front get squeezed up into as little as you'd like, across which you can then wander at local sub-light speed and still arrive rather quicker than going through the "unsqueezed space".

My problem is this: how does the metric modification propagate? Surely it can't move forward faster than light? So, whilst you could bring Alpha Centuauri as near to your backyard as you might like (and then step across the picket fence in the twinkling of an eye) I can't help thinking it's going to take ~4 years to get there.

And on a practical note, what about all the Stuff between here and there? Pile it all up (not forgetting perhaps the Cosmic Microwave Background radiation in addition to bits of real, solid stuff - large and small) and I can't help wondering what it will do to metric on its own.

However, the basic issue - you can't exceed the speed of light in spacetime - remains.

The problems with Wormholes and Time-Machines are related... but that'll have to wait for Part Deux (but in a nutshell: how do you move a wormhole without squeezing and stretching space like the Alcubierre drive (there might be a way - with interesting consequences for time-machine (non) creation - give it a twist... Kerr Metric like), and how in the name of X can Lorentz transformations/boosts be applied to spacetime itself rather than separations within spacetime - i.e. how does time-dilation apply to a moving wormhole mouth? NOT!)

During the interval, if you can explain the fault in the reasoning re the Alcubierre drive above, and how metric modifications propagate FTL do let me know... it will save me making an ass of myself twice (or at least, one more time than I'm going to anyway).

Remember! Einstein was right! (and even if we improve on him, Special/General Relativity will always be suitable approximations for some things..., just as Newtonian gravity still is)

Boldly taking Stuff where no Stuff has gone before.

Enough!

Windows Cannot Find... Resolved!

Ha!

Recently, whenever I double-clicked a Microsoft Word (Word 2002/Word XP) document, Word would start but I would also get an error message from Windows that ""Windows cannot find..." and then the full path to the file I just double-clicked . Naturally I was able to open the file perfectly well once Word was running.

I don't think the general cause or symptoms are application or Windows version specific, so the hint should be good across the board... Vista, XP...

So what gives in this particular case? It could have been a shortcut whose target no longer exists, a missing registry entry perhaps, or if it had been an Excel document (Excel ~20020 ) it might have happened if Excel had been set to ignore other applications - but it wasn't, though the Excel thing a clue (it's a DDE - Dynamic Data Exchange - thing in the end... (or Automation (as they call it now, I think)).

In this case it was all to do with "AutoExec" - which was taking too long to run (lots of Programmatic Stuff). Microsoft has a knowledgebase article for Word2000 that says if AutoExec includes a "Wait" this error can arise, but it's really not the waiting that's important it seems, it's how long the AutoExec takes to complete before Word can respond to the Windows instruction to open the file.

So, the message "Windows cannot find..." is, not unusually, completely misleading: Windows can, has found the file - but the application requested to open the document hasn't responded in time.

And that's it really... to work around the issue I simply took all the long winded stuff out of AutoExec, put it in "delayedAutoExec" and put in this line in the leaner, slimmer, more responsive AutoExec. The delay is short but just long enough for Word to OK the document open request.

Application.OnTime when:=Now + TimeValue("00:00:05"), Name:="delayedAutoExec"

I expect it's also going to cure the bizarre error that was "Application.Activate" failing (during the AutoExec code) because there wasn't, as far as VBA was concerned, any Application to activate!

et voilà, the file is no longer not found.

Pie/Cake Stuff.

"Klum" - A Vital Vista Update

I may need to restart my machine after this - they are clearly tinkering with deep OS code in the update KB955020... it is marked as "Important" - which usually means it fixes something that causes crashes or let's some teen bit-racer leave his hack-tracks all over your disk drive.

What is it about, I hear you ask?

"The words "Friendster," "Klum," "Nazr," "Obama," and "Racicot" are not recognized when you check the spelling in Windows Vista..."

Oh My God! How could they be so stupid?

Or [irony off]... WTF? Is the built in dictionary supposed to know every proper name under the sun? And more to the point, is it not supported by a "Custom Dictionary" to which new words can be added?

When I think of all the little things that Microsoft should be attending to, such as, including but not limited to:

The File Delete/Copy dialog that stays on screen muttering about Zero Seconds to deal with Zero Items after I hit the Cancel button, instead of just disappearing?

The way the Sound Volume, Network and Battery icons disappear from the Sys Tray a.k.a. Notification Area and require a Registry Edit to get them back (hardly beginner stuff, mucking around in the registry).

That folders - and things like the Add/Remove Progams control panel - still forget what columns you chose; that you can't set "File Preview" on a per folder basis.

That if you use 3rd party gadgets in the Sidebar, you get two instances of the Sidebar process - each using up valuable resources - instead of just adding all gadgets to one instance.

That shortcuts to mapped network drives still don't correctly indicate whether or not they are connected/mounted.

[Yes they are getting progressively more trivial... I trust I am making my point]

That if you use the Start button search facility, you don't always get an "Open File Location" option.

No... much more important to ensure that "Klum" is recognised (I suppose that is Heidi Klum), and in all fairness I suppose, Racicot - whoever he/she/it may be. On second thoughts the dictionary should be updated - because unless it is sentences such as "In lieu of serious functional updates, Microsoft has recently taken to issuing turdbright updates in order to better fulfil 'customer expectations'." would get seriously annoying little wiggly lines in them...

Turdbright: chrome-plated faeces. Crap Stuff.

Norwegian Dwarves

Thanks to Runar Larsen, the Norwegian with the Macunian accent from Oslo (or at least one of his mates) en route from Denmark to some Serbian music festival the list is as follows:

Blygen = Shy One = Bashful
Brille = Glasses = Doc
Minsten = Smallest One = ...must be Dopey by elimination
Sinnatabben = Angry Bloke = Grumpy
Lystig = Happy = Happy
Sovnig = Sleepy = Sleepy (should be the o/ thing...)
Prosit = "Bless You", "Atichoo" = Sneezy

[How do you make nice little tables in blogger?]

And now I've thought of somewhere to remember this for me I might put the rest up here too... Farsi, Maori, Swedish, Hungarian, South American Spanish etc. etc. and nary a click within a million miles of a Disney site... all charmed from the natives.

By the way - the list is in the order I was given it. Notice anything odd? Yes, it's in alphabetical order - English Alphabetical Order!Bloody foreigners, come over here with their perfect British accents... learn all our dwarf names.... Oops! I'm not "here" either now.

Dwarves. The Stuff of Fairytales

Earth Devouring Black Hole "Pure Fiction"

Are you worried about the Large Hadron Collider? Are you worried that you aren't worried about it? Should you be worried?

Think about it. If The Large Hadron Collider Produced A Microscopic Black Hole, It Probably Wouldn't Matter at least so says UC Santa Barbara Physics Professor Steve Giddings and his co-author Michelangelo Mangano of... wait for it... the European Centre for Nuclear Research (CERN - it's French) - who are about to turn the LHC!

Do I detect a conflict of interest here? Well, do I?

The idea of particle colliders producing black holes that could devour the Earth might make a good film script but according Steve Giddings, it's just "pure fiction".

Well, They would say That, wouldn't They?

(Am I getting the hang of this conspiracy style thing?)

Junk Stuff (because I can't figure out how to finish the other post on Wormhole time machines, mostly because I haven't the faintest idea how to re-write the metric for a twisted wormhole in Kerr coordinates instead of the customary Schwarzschild coordinates...)